The present invention relates to a laundry treatment machine, in particular to a washing machine for washing laundry or a washer dryer for washing and drying laundry.

EP 3 135 799 Al suggests a washing machine comprising a condenser and an evaporator, wherein the evaporator is arranged within a tank and wherein the tank comprises an inlet and outlet for circulating washing liquid from the tub.

It is an object of the invention to provide a laundry treatment system with an improved washing cycle efficiency.

The invention is defined in claim 1. Particular embodiments are set out in the dependent claims.

According to claim 1, a laundry treatment machine is provided, in particular a washing machine or a washer dryer. The laundry treatment machine comprises: a cabinet housing a tub and a drum rotatably arranged in the tub for washing laundry therein, a heat pump having a compressor, an evaporator and a condenser, the condenser being adapted to heat washing liquid, an evaporator tank housing the evaporator or at least a portion of the evaporator, wherein the evaporator tank is a tank for storing a heat exchanging medium, wherein the evaporator tank is arranged in an upper region of the cabinet, wherein the evaporator tank comprises an inlet and an outlet, wherein washing liquid drained from the tub is passed through the evaporator tank via pipe sections, wherein a first end portion of the pipe sections forms the inlet and a second end portion of the pipe sections forms the outlet, and wherein the outlet defines an outlet level within the evaporator tank and the outlet level is above the upper level of the evaporator pipes within the evaporator tank or above the upper level of the evaporator pipes in the area surrounding the outlet, and/or is below the inner surface of a top cover or ceiling of the evaporator tank. The outlet level may be considered as overflow level. Preferably the outlet and the inlet can be considered as outlet opening and inlet opening, respectively.

The 'outlet level' is a level where the liquid within evaporator tank is flowing out of the evaporator tank if the liquid is above the outlet level and where the liquid stops to flow out of the evaporator tank when the level of the liquid is at or below the outlet level. Preferably at a situation where no liquid is supplied into the evaporator tank.

Preferably the inner surface of a cover or ceiling of the evaporator tank is horizontal or substantially horizontal.

Preferably the pipe section communicating with the outlet or forming the outlet is in fluid communication with the tub, preferably with a bellow of the tub, a sump of the tub or a filter, preferably with a position in the sump upstream of the filter. The filter can be the filter which is normally provided in the passage from the tub (e.g. from the sump) to the drain pump which is draining the washing liquid e.g. after a washing or rinsing phase. Preferably the liquid exiting the outlet can flow by gravity into the tub, the sump or the filter so as to form a draining path. Preferably the draining path is free of barriers that actively have to be activated for the liquid to flow out of the evaporator tank.

The 'area surrounding' the outlet is only a portion of the inner area of the evaporator tank at the height level of the outlet level. For example the surrounding area is less than 1/4, 1/6 or 1/10 of the inner area. Alternatively or additionally the 'surrounding area' is the area within the evaporator tank within a radius of at least 10 mm, 20 mm, 30 mm or 40 mm around the outlet.

The advantage of outlet being arranged at or above highest level of evaporator pipe is: By the outlet being arranged below the inner surface of the top wall of the evaporator tank, a gaseous volume between the outlet and the inner surface of the top wall of the evaporator tank maintains within the evaporator tank.

By arranging the outlet at or above highest level of evaporator pipe and by maintaining a gas volume above outlet, it is ensured that washing liquid can always be circulated through the tank. This prevents the outlet from being blocked when the washing liquid within the tank is frozen.

Preferably, the tank empties automatically due to gravity down to the outlet level of the outlet. Evaporator / Evaporator Tank:

Preferably, the outlet level is at least 2 mm, 4 mm or 6 mm above the upper level of the evaporator pipes within the evaporator tank or above the upper level of the evaporator pipes in the surrounding of the outlet, and/or the outlet level is in a range from 2 - 5 mm, 4 - 7 mm or 6 to 10 mm above the upper level of the evaporator pipes within the evaporator tank or above the upper level of the evaporator pipes in the surrounding of the outlet.

Preferably, the outlet level is at least 3 mm, 6 mm, 9 mm or 12 mm below the inner surface of the top cover or ceiling of the evaporator tank, and/or the outlet level is in a range from 3 - 6 mm, 6 - 9 mm, 9 to 15 mm or 12 to 20 mm below the inner surface of the cover or ceiling of the evaporator tank.

The inlet may define an inlet level and the inlet level is arranged at the same height as the outlet level or above the outlet level. If the inlet level is arranged higher than the outlet level, backflow of the liquid through the inlet pipe is prevented. The 'inlet level' is a level where washing liquid is flowing in the evaporator tank if the liquid is above the inlet level and where the liquid stops to flow in the evaporator tank when the level of the liquid is at or below the inlet level.

Preferably, at least a portion of the second pipe section communicating with the outlet or forming the outlet is at least partially guided through the evaporator tank from below, or the outlet is formed at a side wall of the evaporator tank.

Connection into the evaporator tank from below or from the side saves respective space and enables shorter pipe connections when the evaporator tank is arranged at the upper side or in the top module. The first end portion forming the inlet may be arranged at the bottom of the tank and the second end portion forming the outlet may be arranged at a side wall of the tank or vice versa.

Preferably, the first and second end portions are arranged vertically or substantially vertically or inclined at the bottom wall or horizontally or substantially horizontally or inclined at a side wall of the evaporator tank.

Preferably the first and second end portions are arranged adjacent to each other. More preferably, the first and second end portions (i.e. the inlet and outlet) are arranged in the front right comer at the bottom of the tank when seen the washing machine from a front view.

The first and second end portions (i.e. inlet/outlet) arranged at a side wall of evaporator tank may ensure that the washing liquid circulation at an upper region of evaporator tank (i.e. above the evaporator pipes) is always possible when colder refrigerant (evaporator) pipes are arranged at bottom of the evaporator tank such that ice forms from bottom to top.

Preferably, at least a portion of the first pipe section communicating with the inlet or forming the inlet is at least partially guided through the evaporator tank from below, or the inlet is formed at a side wall of the evaporator tank. By forming the inlet at a side wall, the pipe section comprising the inlet is not guided through the inside of the tank. This may prevent the inlet and the washing liquid in the pipe sections communicating with the inlet from freezing.

Preferably, the pipe sections extend from the inside to the outside of the evaporator tank, and wherein at least one section of the pipe sections outside the evaporator tank is at least partially angled. The section outside the evaporator tank may be angled e.g. by 30, 40, 60 or 100 degrees, preferably by 90 degrees. This saves space inside the washing machine, in particular at the top area of the washing machine. In particular when a pipe section is arranged at a side wall of the evaporator tank, this may prevent the pipe section from protruding beyond the top module, in particular the tray element, when looking at the washing machine from a top view.

Preferably, the evaporator tank comprises an upper region accommodating a first portion of the evaporator and a lower region accommodating a second portion of the evaporator, wherein the first and second portion of the evaporator are arranged at vertically different levels, and wherein the horizontal cross-section area of the lower region is less than the horizontal cross-section area of the upper region.

The type of washing liquid passed or circulated through the condenser unit depends on the phase of the washing cycle during which the liquid is passed or circulated.

Preferably it is a washing liquid having resolved therein washing agents, e.g. a washing detergent during a washing phase. However the 'washing' liquid may also be water before supplying the washing agent or washing detergent, or rinsing liquid for rinsing having a softener or not or a treatment liquid having resolved therein a bleach or a impregnant agent.

A 'region' represents a volume region within the evaporator tank having a vertical extension and being defined between a (fictive) lower and upper horizontal crosssection area within the inner tank space. The vertical extension is such that a respective portion of the evaporator is positioned within the volume region. Preferably the horizontal cross-section area of a (upper/lower/intermediate) region is an average horizontal cross-section area of the respective region, e.g. averaged over all crosssections over the vertical extension of the respective region. The lower or upper regions are not regions located within a stub or connector which is connected to the evaporator tank. I.e. the regions are regions conventionally considered to be arranged within the tank volume as such and not within extensions external to the tank volume provided e.g. for peripheral (liquid) connection purposes.

The volume region of the lower region is arranged below the volume region of the upper region. In top view the volume region (e.g. the upper and lower horizontal crosssection area) may be above each other or at least partially offset to each other.

Preferably there is a full or partial overlap of the upper and lower region when seen from above - i.e. the vertical projection of the lower region onto the upper region overlaps at least partially with the upper region.

'Vertically different levels' means that the lower region accommodating the second portion of the evaporator and the upper region accommodating the first portion of the evaporator are arranged in volume regions at different vertical height within the tank inner volume, i.e. the volumes of the upper and lower regions have no overlap volume.

Preferably the vertical extension of the 'upper region' and 'lower region' each corresponds at least to the thickness of at least one pipe of the evaporator or, if a microchannel is used instead of pipes, to the height of a microchannel. In particular, the vertical extension of the lower region and/or the upper region may be in the range of 1-2 cm, 2-4 cm, 3-5 cm, 4-7 cm or 5-9 cm. Upper and lower regions may have different vertical extensions, for example selected from these listed extension ranges.

The volume ratio between the lower region and the upper region may be in the range of 1 : 1- 1 :2, 1:1, 5-1:3, 1 :2-l :4 or 1 :3-l :6, preferably the ratio is in the range of 1:1,25-1:1,75. Preferably this volume ratios apply when the upper and lower region have the same height (i.e. the tank is tapering downwards)

Preferably in a horizontal orientation of the evaporator tank (e.g. installed in the top), the ratio between height extension and width and/or depth extension is or is at least 1/5, 1/8, 1/10 or 1/12. In addition or as an alternative, the ratio between the volumes of the upper and lower regions may be at least 1:0,8; 1:0,6; 1:0,5; 1:0,4 or 1:0,25.

The evaporator tank is external to the tub, in particular the tank is arranged above the tub and/or extends below the top module, more preferably within the top module.

The evaporator tank is preferably a continuous tank, in particular the lower and upper region of the evaporator tank are connected to each other forming a single tank. Two single tanks that are only fluidically connected to each other are excluded by this definition.

Preferably, the evaporator tank "tapers downward" which means that the horizontal cross-section area of the lower region of the tank is smaller than the horizontal crosssection area of the upper region. When the evaporator tank is seen in top view, the area of the lower region is less than the area of the upper region of the tank. Preferably the tank is tapering in that the horizontal cross-section area of the inner tank space is monotonically or strong monotonically decreasing from top down and/or the horizontal cross-section area is reducing in one or more steps (e.g. one, two or three steps) from top down.

The lower and upper region of the evaporator tank may have one of the following vertical cross-section areas when seen the tank in front view (with respect to the washing machine): a) at least one of the upper region and lower region has a rectangular form, wherein the horizontal cross-section area of the lower region is smaller and therefore forms a step between the upper region and the lower region; b) upper region and lower region forming a triangle wherein the horizontal crosssection area of the lower region is smaller than the horizontal are of the upper region; this shape is preferably used if a microchannel arrangement is used instead of evaporator pipes; c) upper region and lower region forming a rounded area at one side of the crosssection of the tank; in particular, the curvature of the rounded area corresponds or substantially corresponds to the curvature of the tub; saving space by this design

By stacking or arranging the evaporator at different vertical height levels and when considering a fixed horizontal maximum extension of the evaporator tank, the heat exchanging surface or capacity of the evaporator is increased. E.g. more and/or longer evaporator pipes can be arranged within the same food area of the evaporator tank. Thus, the required compressor power is lower for the same amount of heat exchange.

Preferably at least 20%, 30%, 40% or 50% of the evaporator (the first and/or second evaporation portion) is arranged in the lower portion and/or in the upper portion. Explanation: The percentage of the evaporator in the upper and lower portion sum up to 100% or the percentages of the evaporator in the lower and upper portion do not sum to 100% and in this case the rest to 100% is arranged in one or more intermediate regions (described below) between the upper and lower region. The percentage of the evaporator may be referred to the length, the heat exchanging capability, the volume or the weight of the evaporator, the number of windings of a meandering evaporator or two or more of these parameters.

'Module comprises' means that the respective comprised components form part of the top module and are preferably mounted to the top module. The top module may comprise a tray element. A top wall of the washing machine is preferably mounted on top of the tray element. Preferably the top module has on its upper side a working top which for example is the top wall in the shape of a plate. The components of the top module are pre-assembled such that the top module can be assembled as a whole to the upper side of the laundry treatment machine.

The condenser is adapted to heat the washing liquid at least in a first operation mode of the laundry treatment machine. In an embodiment and in a second operation mode the condenser is adapted to cool the washing liquid as described below (e.g. in case of reversal of the refrigerant flow).

Alternatively, a) the evaporator tank is a flow-through tank comprising an inlet and an outlet, wherein washing liquid from the tub is passed through the evaporator tank via the inlet and outlet and wherein the washing liquid is the heat exchanging medium. Or b) the evaporator tank comprises a first and a second container chamber, wherein the first container chamber houses the evaporator or at least a portion of the evaporator and permanently stores the heat exchanging medium, wherein the second container chamber is a flow through-tank chamber comprising an inlet and an outlet, wherein the second container chamber is in heat contact with the heat exchanging medium in the first container chamber and wherein washing liquid drained from the tub by a chamber circulation pump is passed through the second container chamber via the inlet and outlet, and wherein an inlet of the chamber circulation pump (mixing pump) is connected to the tub or the sump of the tub and an outlet of the chamber circulation pump is connected to the inlet of the second container chamber.

Preferably, the arrangement of the evaporator tank with the upper region and lower region accommodating portions of the evaporator are arranged in the first container chamber of the evaporator tank.

According to version b) two fluidly separated chambers are formed in one container forming the evaporator tank, wherein the container is integrated in the top. Preferably the container is formed integrally with the top or integrally with a tray of the top.

The 'washing liquid' may be the washing liquid used during a washing phase or the rinsing liquid used during a rinsing phase or generally the treatment liquid used during any of the laundry treatment phases.

'Permanently storing' means that in normal user operation the heat exchanging medium is not exchanged or refreshed. The medium may be filled during manufacturing of the machine or when setting the machine to operation at the installation place. The medium may be exchanged by maintenance case e.g. by a service person. When permanently storing the heat exchanging medium, a medium may be used having a higher heat storing capacity and/or a higher latent heat (enthalpy of fusion) than the washing liquid which basically is water.

Applicable for versions a) and b): The 'washing liquid drained from the tub' is the washing liquid that was used for treatment of laundry in the tub and which is extracted from the tub. The extraction from the tub may be made through an outlet provided at the tub wall or preferably through the sump of the tub or a sump portion fluidly connected to the tub. Preferably the washing liquid is extracted downstream of a filter which is filtering the washing liquid extracted from the tub or sump. The filter is preferably arranged upstream of the chamber circulation pump (mixing pump). Preferably the filter housing in which the filter is arranged is part of the sump.

Preferably, the washing liquid that has passed through the second container chamber (version b)) or through the evaporator tank (version a)) is reintroduced into the tub, preferably via a bellow of the tub, a sump, or a filter, preferably at a position in the sump upstream of the filter. The filter can be the filter which is normally provided in the passage from the tub (e.g. from the sump) to the drain pump which is draining the washing liquid e.g. after a washing or rinsing phase.

Applicable for version b): Preferably, there is a gaseous volume above the heat exchanging medium in the first container chamber. Thus the heat exchanging medium has enough space during freezing due to the increase in volume. As long as the gaseous volume is present, a reduced heat exchange between the heat exchanging medium in the first container chamber and the washing liquid in the second container chamber is accepted. Once the heat exchanging medium gets iced, the gaseous volume is preferably absent (e.g. displaced and/or compressed by the iced heat exchanging medium) and therefore when liquid from the tub is circulated through the second container chamber an efficient heat exchange between the first and second container chamber may be obtained.

Applicable for versions a) and b): Preferably the washing liquid flows back into the tub or sump fluidly connected to the tub or another fluid line fluidly connected to the tub (e.g. the detergent housing or a passage from the detergent drawer to the tub). Alternatively and/or selectively the fluid is passed into a drain line that is used by the drain pump for draining washing or rinsing liquid.

Applicable for versions a) and b): Preferably the washing liquid is extracted from the tub, the sump or any other line fluidly connected to the tub by a chamber circulation pump. The chamber circulation pump may be operated at the end of a laundry treatment phase (e.g. washing phase or rinsing phase). Preferably the chamber circulation pump is operated before operating the drain pump or at least partially simultaneously with operating the drain pump. E.g. when the chamber circulation pump is fluidly connected to the sump and when then or simultaneously the drain pump is operated, 'fresh' washing liquid is extracted by the drain pump via the sump from the tub such that when the chamber circulation pump is also fluidly connected to the sump the chamber circulation pump at least partially extracts washing liquid freshly provided from the tub by the activity of the drain pump. A circulation of the 'same' washing liquid from the sump to the evaporator tank is avoided such that fresh and warmer washing liquid is fed into the circulation to the evaporator tank. Preferably the washing machine comprises a control unit that is adapted to control the operation of the chamber circulation pump as described herein and in particular as described in this paragraph.

Applicable for version b): Preferably the washing liquid is fed to the second container chamber via pipe sections which extend through the first container chamber, wherein in particular a first pipe end forms the inlet of the second container chamber, and a second pipe end forms the outlet of the second container chamber. Thus, the washing liquid is guided through the first container chamber.

Preferably, the inlet and outlet of the second container chamber are arranged at the bottom of the second container chamber. More preferably, the pipes extend vertically or substantially vertically from the bottom of the first container chamber to the bottom of the second container chamber.

Preferably, the first pipe connects an inlet of the first container chamber with the inlet of the second container chamber, and the second pipe connects an outlet of the first container chamber with the outlet of the second container chamber, in particular such that the washing liquid is guidable through the first container chamber. The inlet and outlet of the first container chamber are preferably arranged at the bottom of the evaporator tank, in particular at the bottom of the first container chamber. Alternatively, the inlet and outlet of the first container chamber may be arranged at a side wall of the first container chamber, wherein in this case the pipes extend from the side wall to the inlet and outlet of the second container chamber.

Preferably, the second container chamber is arranged above and in heat contact with the first container chamber. Preferably, when the heat exchanging medium within the evaporator tank is not iced or only partially iced a gaseous volume is maintained above the heat exchanging medium. As long as the gaseous volume is present, a reduced heat exchange between the heat exchanging medium in the first container chamber and the washing liquid in the second container chamber is accepted. When the heat exchanging medium is completely iced, the gaseous volume may be filled by the iced heat exchanging medium and a heat contact between the washing liquid flowing through the second container chamber and the iced heat exchanging medium is obtained. This arrangement ensures that frozen heat exchanging medium that has formed in the first container chamber can be dissolved by the circulation of the washing liquid through the second container chamber which results in an improved operation efficiency of the laundry treatment machine.

Throughout this description the terms 'ice', 'freezing' and 'melting' generally describe the change of phase states from liquid to solid and vice versa, respectively, independent whether it relates to water (washing = laundry treatment water) as heat exchanging medium or any other heat exchanging medium used for storing/releasing heat accompanied by a phase change, e.g. the liquid/solid phase change.

Preferably, the first and second container chambers are formed by a single or integral container. "Single or integral container" means that the second container chamber and the first container chamber share a common wall, in particular a separation wall, i.e. only a single container, namely the evaporator tank, is visible from the outside. Preferably, the separation wall forms the bottom wall of the second container chamber and the top wall of the first container chamber. This results in less risk of leakage as the first and second container chambers share a common wall. Preferably, the integral container is also integrally formed with the top or integrally with the tray element of the top.

More preferably a separation wall is inserted in the container separating the first and second container chamber from each other. The separation wall fluidly separates the first and second container chambers from each other. Preferably, the separation wall is arranged horizontally between the first and second container chambers. As the separation wall may be not or only very slightly mechanically loaded, the material of the separation wall can be freely chosen. The separation wall may be made of e.g. thin Aluminium for improved heat exchange between the first and second container chambers. The separation wall may be made of a flexible material with less stiffness for compensating the volume change of the mediums within the first and/or second container chamber, in particular of the heat exchanging medium in the first container chamber. In this case, no gaseous volume may be provided above the heat exchanging medium in the first container chamber as the volume change of the medium when icing may be compensated by an elastic deformation of the flexible separation wall.

Preferably, the second container chamber comprises guiding (separation) elements for guiding the washing liquid along a predetermined path within the second container chamber. More preferably, the guiding elements are formed such that the liquid passes through the second container in meandering shape/form. The guiding elements may be configured such that the inlet and outlet of the second container chamber are separated from each other. Thus, the washing liquid flowing into the second container chamber has to flow along the whole predetermined path before exiting the second container chamber. Preferably, the guiding elements are configured such that the washing liquid flows along the whole or substantially whole top surface of the first container chamber.

Preferably, the guiding elements are arranged at the upper surface of the separation wall and/or the lower surface of the evaporator tank cover, more preferably are formed in a single piece with the separation wall and/or the evaporator tank cover. In case the second container chamber is formed by the evaporator tank cover, the guiding elements may be arranged at the upper surface of the tank cover, preferably protruding from the upper surface of the tank cover into the second container chamber. Preferably, the top of the tank cover is covered by a further cover (e.g. a lid).

Preferably the guiding elements extend vertically over the entire height of the second container chamber and/or between the upper surface of the separation wall and the lower surface of the further cover (i.e. a cover covering the second container chamber from above).

The circulation of the washing liquid in versions a) and b) between the tub and the tank ensures that the evaporator tank is deiced and thus it is always possible to drain water from the tank.

Applicable for version a): Preferably an overflow is arranged within the evaporator tank, wherein the overflow may be configured such that the tank is only partially filled with the washing liquid and a gaseous volume is maintained above the washing liquid level. In particular, the washing liquid only rises to a predefined washing liquid level and then flows off the evaporator tank via the overflow.

Applicable for version a): Preferably the evaporator tank, in particular the evaporator tank cover, comprises a separation (guiding) element arranged at the top of the evaporator tank and facing the inside of the tank, wherein the separation element is configured such that the inlet and outlet within the tank are separated from each other and/or the washing liquid is guided along a predefined path within the tank (or along an at least partially predefined path within the tank). The predefined path may ensure that the supplied water from the tub always has to flow over the entire or substantially entire ice formed around the evaporator pipes. I.e. when the ice is melt, the water may pass past all or substantially all pipes of the evaporator before it is discharged at the outlet (via overflow) of the tank. I.e. during melting of the ice in the evaporator, the water may flow past the entire ice formed in the evaporator. In particular the separation wall provides that in case of frozen liquid in the tank the liquid supplied into the tank flows over the surface of the frozen liquid before exiting the tank.

Applicable for versions a) and b): Preferably, the washing liquid drained from the tub is passed through the evaporator tank via pipe sections, wherein a first end portion of the pipe sections forms the inlet and a second end portion of the pipe sections forms the outlet, and wherein the outlet defines an outlet level within the evaporator tank and the outlet level is above the upper level of the evaporator pipes within the evaporator tank or above the upper level of the evaporator pipes in the area surrounding the outlet, and/or the outlet level is below the inner surface of a top cover or ceiling of the evaporator tank.

Preferably, the evaporator comprises a refrigerant tube arranged in meandering form in the evaporator tank, wherein a first number of windings of the meandering form is positioned in the first region and a second number of windings of the meandering form is positioned in the second region, or the evaporator is an evaporator block or an evaporator battery which is oriented inclined to a horizontal plane such that a portion of the evaporator block or battery is positioned in the upper region and forms the first portion and another portion of the evaporator block or battery is positioned in the lower region and forms the second portion.

A 'portion of the evaporator' may comprise evaporator pipes extending in the same horizontal level.

Alternatively, the pipes of a portion extending in vertically different levels, wherein the pipes are arranged above each other or at least partially horizontally offset to each other. A portion may comprise two pipes (windings of the meander), but may also comprise e.g. three, four or five pipes (windings of the meander) arranged above each other.

Alternatively, the evaporator may extend obliquely from the upper region to the lower region, in particular if a microchannel arrangement is used instead of a meandering evaporator pipe. The windings of the meandering evaporator pipe in the upper region and the windings of the meandering evaporator pipe in the lower region may be crossed to each other (when seen from above), e.g. the meanders of the upper region and these of lower region are arranged each in a plane and the orientation is crossed e.g. under 90°;

Preferably, the horizontal cross-section area of the lower region is in the range of 15- 25%, 20-40%, 30-60% or 50-80% of the horizontal cross-section area of the upper region. The 'horizontal cross-section area' can here also be understood as the average horizontal cross-section area of the lower and upper region, respectively.

The upper region and lower region of the evaporator tank may have a rectangular form, wherein the horizontal cross-section area of the lower region is smaller and therefore the tank comprises a step between the upper region and the lower region when seen the tank in vertical cross-section in front view of the washing machine.

The above percentage ranges apply when the evaporator tank is viewed from above, e.g. when the tank is seen in projection from above. Preferably, the horizontal cross-section area of the lower region is less than 60%, 45% or 30% of the horizontal cross-section area of the upper region.

The evaporator tank may be only partially filled with the heat exchanging medium and a gaseous volume is provided above the upper region within inner space of the evaporator tank above the heat exchanging medium, in particular above the inlet and outlet of the evaporator tank. The gaseous volume is preferably air, but may also be any other kind of gas, e.g. nitrogen. When the heat exchanging medium in the evaporator tank freezes, the gaseous volume allows the ice to expand freely. Thus, there is no mechanical pressure by ice onto the bottom of the tank and the tank is not damaged by the expansion of the ice.

In case of a flow-through tank (i.e. one tank with one chamber), the gaseous volume is preferably provided between the inner surface of the top cover or ceiling of the evaporator tank and the inlet/outlet level.

In case of a tank comprising a first and second container chamber, the gaseous volume is preferably provided within the first container chamber above the evaporator, in particular between the upper level of the evaporator and the lower surface of a separation wall separating the first and second container chambers from each other. Additionally a gaseous volume may be provided within the second container chamber between the inlet/outlet level and the inner top surface of the second container chamber.

Preferably, the ratio between the volume of the gas in the tank and the volume of the heat exchanging medium is in the range of 6-12%, 4-8% or 10-15% (volume ratio at room temperature and/or volume ratio of the inner space of the tank separated by the liquid level). The evaporator tank may have a capacity in the range of 2,5-4, 3, 5-5, 5, 4,5-7 liters, preferably in the range of 4,5 to 5,5 liters. If for example the evaporator tank has a volume to receive about 4,8 liters, when starting with the heat exchanging medium at room temperature and when supplying about 5,5 liters tap water into the tub for washing an average laundry load of 4 kg (dry), the washing water can be heated with the heat from the evaporator tank up to 45 °C corresponding to a normal washing temperature.

The height (vertical extension) of the gaseous volume may be 1, 1,5, 2 or 2,5 cm and/or the ratio of gaseous volume and heat exchanging medium in the tank may be 1/10. Preferably, the gaseous volume is evenly distributed over the (uppermost) horizontal cross-section area of the upper region.

Preferably, the evaporator tank comprises at least one intermediate region located between the upper region and the lower region, wherein the at least one intermediate region preferably comprises a third or further portions of the evaporator.

The 'intermediate region' may have a horizontal cross-section area which is between the horizontal cross-section areas of the upper and lower region ('horizontal cross-section area' can here also be understood as the average horizontal cross-section area over the whole vertical range of the respective region).

Preferably, the horizontal cross-section areas decrease in steps from the upper region to the intermediate region and from the intermediate region to the lower region. Preferably, the tank comprises at least two steps, when the tank is seen in vertical cross-section in front view of the washing machine. The upper region, the at least one intermediate region and the lower region form a continuous evaporator tank. At least one side wall of the tank enclosing the volume of the intermediate region may be a vertical, inclined or rounded side wall. The intermediate region may have a height in the range of 1-3, 2-4, 3-5, 4-6 or 5-7 cm. Preferably, the evaporator tank may comprise any number of intermediate regions, e.g. one, two three, four or five, wherein each one of the regions may comprise a portion of the evaporator.

Preferably, the refrigerant circuit of the heat pump is designed such that the refrigerant enters the evaporator at the first evaporator portion of the lower region, and/or the refrigerant exits the evaporator in the evaporator tank from the second portion of the evaporator in the upper region, and/or the heat pump further comprises an expansion device positioned in the refrigerant circuit upstream of the second portion of the evaporator in the lower region. Considered here is the normal flow direction of the refrigerant where the evaporator operates as evaporator and the condenser operates as condenser. 'Upstream' of the second evaporator portion means that the expansion device is positioned in the refrigerant circuit between the condenser and the second portion of the evaporator. The expansion device may be a valve, a capillary or an expansion valve which optionally may have an adjustable refrigerant flow rate.

The coldest water is due to convection at the bottom of the tank. This causes the lower pipes of the second portion of the evaporator in the lower region to freeze first. The ice which is forming in the lower region of the tank pushes the unfrozen water upwards where preferably the tank has a free (gas-containing) volume for receiving the water and subsequently the ice due to the ice expansion. Ice formation starting in the lower region of the tank ensures that the upper region of the evaporator tank can still exchange heat during formation of ice.

Preferably, the first and/or second portion of the evaporator is formed with pipes, windings of pipes or with microchannels. Microchannels have a better heat exchange efficiency, e.g. less volume of tank and/or a shorter evaporator are required for the same amount of heat exchange. In the case of pipes, the pipes may be arranged in the upper and lower region of the evaporator tank horizontally and/or may be arranged inclined extending from the upper region to the lower region of the tank. In the case of microchannels, the whole microchannel arrangement is preferably arranged obliquely extending from the upper region to the lower region of the tank, when seen the tank in a vertical cross-section in front view of the washing machine. It is also possible to arrange several microchannel arrangements obliquely, but parallel to each other in the tank. Alternatively, at least one microchannel arrangement may be arranged in the upper and lower region, respectively (i.e. the microchannels are arranged horizontally in different heights to each other). Preferably, the lower microchannel arrangement is more compact then the upper microchannel so that the lower microchannel arrangement fits in the lower portion (with smaller horizontal cross-section area) of the evaporator tank. The microchannels of the upper and lower region may be arranged above each other or may be at least partially horizontally offset to each other.

Optionally the first portion of the evaporator forms a first evaporator block or battery and/or the second portion of the evaporator forms a second evaporator block or battery, wherein preferably the two blocks are connected by an interconnection pipe to each other and/or an exit header of the one block/battery forms the inlet header of the other block/battery.

In case the evaporator is formed by pipes or winding of pipes, the length and/or the heat exchanging surface of the pipes or windings of the evaporator may be different in the upper region and the lower region. The 'length' corresponds to the longitudinal extension of the pipes when the portion of the evaporator is straightened to a line. Preferably, the length and/or the heat exchanging surface of the pipes or windings of the evaporator arranged in the lower region is shorter/smaller than the length and/or the heat exchanging surface of the pipes or windings of the evaporator arranged in the upper region.

Preferably, the evaporator tank comprises ribs and/or seats arranged on a top surface and/or a bottom surface of the evaporator tank for receiving a thermo-insulating material. More preferably the top and/or bottom surfaces are the outer surfaces of the evaporator tank. The thermo-insulating material avoids heat dispersion. In case the compressor is mounted on the top, such material can also dampen vibrations. Preferably, the ribs and/or seats are evenly distributed over the top outer surface and/or bottom outer surface of the tank. The ribs may increase the stability of the evaporator tank/top module and/or may form spaces (seats) for receiving a thermo-insulating material. In particular, the spaces may be formed by intersection of at least three ribs, preferably by the intersection of four ribs forming rectangles.

The evaporator tank preferably comprises an evaporator tank cover. The evaporator tank cover preferably seals the tank tightly such that no liquids and/or gases are able to escape. The evaporator tank cover may also comprise ribs and/or seats on a top surface or a bottom surface, preferably on a surface facing the top wall.

Top Module:

Preferably, the laundry treatment machine further comprises a top module, wherein when the top module is mounted at the laundry treatment machine it is forming part of the cabinet as a top, and wherein preferably the top module comprises the evaporator tank and the evaporator and preferably the condenser or at least a portion of the condenser.

In an embodiment the evaporator tank together with the evaporator and/or the condenser unit are arranged at the top of the laundry treatment machine in a pivotable manner. For example, a hinge may be provided such that the evaporator tank and/or the condenser unit can be pivoted at one side (e.g. at the lower end or at a lateral side of the evaporator tank and/or condenser unit) so that for mounting and/or maintenance purposes (change of the drum driving belt) the tank and/or unit can be pivoted to the top e.g. after releasing some mounting and/or snap-fit elements supporting the tank and/or condenser at the machine top or housing frame.

Alternatively, or additionally the condenser unit and/or evaporator tank are provided as a ready-to-be mounted module mounted at the top or top region of the machine cabinet. Preferably the module is pivotably supported at the machine cabinet or top or cabinet supporting frame.

Condenser Unit / Tube-in-Tube Arrangement:

The condenser unit may have an elongate longitudinal extension and one or more of the following may be applicable: (a) the condenser unit is extending along two sides, along three sides or at least three sides of the evaporator tank, (b) the condenser unit is guided around the evaporator tank covering an arc around the evaporator tank of at least 70°, at least 80°, at least 100° or at least 120°, and (c) the ratio R between the condenser unit longitudinal extension L to the condenser unit maximum or average cross extension Q is at least 10, at least 15 or at least 20.

The alternatives (a), (b), and/or (c) are the following and are disclosed herein. The condenser unit may be combined with (a), or (b), or (c), or (a) and (b), or (a) and (c), or (b) and (c), or (a) and (b) and (c). In this or an analog way all and/or conjunctions mean this single or multiple combinations.

'Longitudinal extension' is the extension when the condenser unit is straightened to a line and such straightening is 'theoretically' not deteriorating the heat exchanging efficiency of the condenser unit. The 'extending along sides' preferably means that the condenser unit extends in a horizontal plane around the evaporator, preferably around the upper region of the evaporator tank. The 'arc around the condenser' is measured from the geometrical 'center' of the evaporator tank.

Preferably, the washing liquid is washing liquid circulated from the interior of the tub through the liquid passage (see below). Alternatively or additionally the washing liquid may be water supplied from an external water tap or a mixture of water supplied from the external water tap and a washing agent (e.g. detergent, conditioner, softener and the like).

Preferably at least 80%, 90% or the whole condenser unit is guided along an outer wall of the evaporator tank - with respect to the length of the condenser unit which is in heatexchanging contact between the refrigerant passage and the washing liquid passage.

In addition or as an alternative, the ratio R between the condenser unit longitudinal extension L to the condenser unit maximum or average cross extension Q is at least 10, at least 15 or at least 20.

'Guided around' and 'extending along' are to be seen in a perspective perpendicular to extension planes, e.g. in a top view when the top module is in its operational orientation on the laundry treatment machine. 'Extension planes' are filling the respective volumes occupied by the outer dimensions of the curved condenser unit and evaporator tank and have a 'flat' dimension as compared to the other two dimensions of the evaporator tank and curved condenser unit.

An extension plane where the condenser unit is arranged and an extension plane where the evaporator tank is arranged may overlap or may partially overlap or may be arranged in proximity but minimally spaced of each other, in particular when seen in side view (operational orientation). The condenser unit may be formed of or may comprise tubes arranged in heat contact with each other, wherein in at least one tube the refrigerant is flowing and/or in at least one other tube the washing liquid is flowing. E.g. the refrigerant tube(s) is in heat contact with the washing liquid tube(s).

Preferably, the condenser unit is guided around at least three sides of the evaporator tank forming an asymmetric spiral shape. 'Asymmetric spiral shape' means that the condenser unit does not form a curve that runs only around a first point, but a curve where at least two sections of the condenser run around a first and a second points (points of different position). Preferably, the condenser unit is guided around the evaporator tank and forms another spiral portion next to the evaporator tank. This results in an extended condenser unit in the top module with a higher heat exchange efficiency. Thus, the required power of compressor is lower.

Preferably, the condenser unit has 1,2-1, 4, 1,3-1, 5, 1,4-1, 6, 1,5-1, 7 or 1,6-1, 8 windings when mounted in the laundry treatment machine. 'Windings' are meant to be windings arranged above each other or arranged inside of each other (i.e. adjacent windings are not meant here). Following the curve of the condenser from the beginning, one winding corresponds to the length until the starting point is reached or is substantially reached again. In case of the asymmetric spiral shape described above, the first winding is counted regarding the first point and starting from the end of the first winding the second winding is counted regarding the second point whose position differs from the position of the first point.

Preferably, the longitudinal extension of the condenser unit is in a range between 1,0- 1,2, 1,1-1, 4, 1,2-1, 5 or 1,3-1, 7 m. This results in an improved heat pump efficiency by increasing the surface for heat exchange. The heat pump may thus be faster at operation (steady) condition, in particular faster in warming water. By increasing the condenser length, the heat pump is more efficient, e.g. less waist heat exchange to external air. The required compressor power is lower for the same amount of heat exchange between the refrigerant and the washing liquid each flowing through the condenser unit.

The condenser unit may be or may comprise a tube-in-tube arrangement, where a smaller diameter tube is arranged in a larger diameter tube, wherein in particular in the larger diameter tube the refrigerant (or the washing liquid) is flowing around the smaller diameter tube and wherein in the smaller diameter tube the washing liquid (or the refrigerant) is flowing. Alternatively, microchannels are arranged in the larger diameter tube, wherein in particular the refrigerant (or the washing liquid) is flowing in microchannels around the smaller diameter tube and wherein in the smaller diameter tube the washing liquid (or the refrigerant) is flowing.

When the refrigerant is flowing in the larger diameter tube (outer tube), the required cross-section for refrigerant flow is low and at the same time the heat exchanging area is increased as compared to the refrigerant flowing in the inner tube, as the cross-section for the inner tube where the washing liquid flows is high. On the other hand, the washing liquid flow in the smaller diameter inner tube may reduce the risk of clogging as the tube wall surface is minimized (e.g. no outer surface of an inner tube).

Microchannels have better heat exchange efficiency and thus shorter longitudinal extension of the evaporator for same amount of heat exchange compared to normal tube-in-tube arrangement without microchannels is required. In addition or as an alternative, the compressor dimension (e.g. the compressor outer dimensions and/or the pumping power of the compressor) could be reduced. Preferably, the compressor dimension is maintained and the heat pump efficiency is improved by using microchannels.

The material of the pipes of the condenser and/or evaporator is copper or aluminum, in particular the material of the inner and/or outer pipes of pipe-in-pipe condenser is aluminum or copper. The refrigerant is for example R134a or R290 (propane). If propane is used, then the length of the pipes (and therefore the volume) is reduced for security reasons. E.g. the maximum refrigerant amount in the heat pump system is or is below 350 gr propane.

Preferably the refrigerant and the washing liquids are flowing in opposite directions in the heat-connected tubes (counterflow) resulting in higher heat exchanging efficiency (considering here the normal flow direction of the refrigerant when the condenser operates as condenser). The condenser unit may be enclosed by a heat insulating layer, specifically in case of a tube-in-tube arrangement. 'Enclosed' means that essential parts of the condenser unit are heat insulated.

The inner tube of the condenser unit may have an inner diameter in the range of 10 to 14 mm, 13 to 17 mm, or 16 to 22 mm) and/or may have a wall thickness in the range of 0,7 to 1 mm, 0,9 to 1,5 mm, 1,4 to 2,2 mm or 2 to 2,5 mm. In addition or as an alternative the outer tube of the condenser unit may have an inner diameter in the range of 15 to 21 mm, 19 to 25 or 22 to 24 mm and/or may have a wall thickness in the range of 0,7 to 1 mm, 0,9 to 1,5 mm, 1,4 to 2,2 mm or 2 to 2,5 mm. In addition or as an alternative, the heat insulation layer around the outer tube may have an outer diameter in the range of 25 to 28 mm, 27 to 32 mm or 30 to 36 mm.

Alternatively or specifically the inner tube may have an inner diameter of 16 mm (or 12, 14, 18 or 20 mm) and/or may have a wall thickness of 1 mm, 1,5 mm, 2 mm or 2,5 mm. In addition or as an alternative the outer tube may have an inner diameter of 20 mm (or 16, 18, 22 or 24 mm) and/or may have a wall thickness of 1 mm, 1,5 mm, 2 mm or 2,5 mm. In addition or as an alternative, the or an insulation layer around the outer tube may have an outer diameter of 32 mm (or 28, 30, 34 or 36 mm).

A portion of the condenser unit may be in heat contact with the heat exchanging medium in or of the evaporator tank. It may be a small portion that is in heat contact with the heat exchanging medium as compared with the portion of the condenser that is in heat contact with the washing liquid. Preferably, the portion that is in heat contact with the heat exchanging medium is at the refrigerant outlet end portion of the condenser. More preferably, the ratio between the portion of the condenser unit which is in heat contact with the heat exchanging medium and the portion of the condenser which is in heat contact with the washing liquid is or is less than 1/5, 1/10 or 1/20. Preferably the portion in contact with the heat exchanging medium is at the refrigerant outlet end portion of the condenser.

If for example the heat transfer to the washing liquid is no longer required or possible (e.g. no circulation, washing liquid maximally heated) then the residual heat of the heat pump may be deposited in the evaporator tank so that this heat can be extracted in the next washing cycle for heating the circulated liquid.

Compressor:

The compressor may be mounted at the top module or in a bottom region of the cabinet. The compressor may be a variable speed compressor with variable refrigerant flow rate. When mounted at the top the compressor motor axis is oriented vertical or parallel to the top surface of the laundry treatment machine. For using interior space optimally, when mounted at the bottom of the cabinet, the compressor motor axis may be in a horizontal plane or may be inclined maximally 15° to the horizontal plane. In case the laundry treatment machine is a washing machine, the following applies: Preferably the compressor is arranged in a bottom region of the cabinet if the height of the washing machine is cabinet 85 cm. Alternatively, the compressor may also be arranged at the top of a washing machine with a cabinet height of 87 cm.

When compressor is mounted at the top, the compressor is preferably mounted at the top with screws. A further screw may be used to block (transport lock) the compressor when the laundry treatment machine is transported. Three screws are normally used to block the tub. The compressor is preferably mounted on rubber blocks for dampening vibrations. The compressor weight may be 6 to 7 kg.

In case the laundry treatment machine is a washer dryer, the following applies: Preferably the compressor in a washer dryer is arranged in a bottom region of the cabinet. In practice, the washer dryer is possible with a cabinet height of 85 cm only if the evaporator tank is flat and the counterweight above the tub is removed. Due to the air conduits above the tub in a washer dryer, there may not be enough space for an arrangement of the compressor at the top. In a washer dryer with a cabinet height of 87 cm, there may be enough space for an evaporator tank which is not flat and/or the counterweight may be arranged above the tub.

Circulation Unit

Optionally the heat pump comprises a switching element (e.g. a switching valve) arranged in the refrigerant circuit which is adapted to be switched between a normal refrigerant flow direction and a reverted refrigerant flow direction. In the normal refrigerant flow direction the evaporator operates as evaporator and the condenser operates as condenser. In the reverted or reversed refrigerant flow direction the evaporator operates as condenser and the condenser operates as evaporator. Preferably the switching element is mounted and/or arranged in the top module, in particular in the tray element of the top module.

In a first operation mode (normal refrigerant flow direction), which is a washing operation mode, the condenser unit is adapted to heat the washing liquid and the evaporator is adapted to cool the heat exchanging medium. In a second operation mode (reverted refrigerant flow direction), the condenser unit is adapted to cool the washing liquid and the evaporator is adapted to heat the heat exchanging medium. Preferably the second operation mode is used for de-icing the evaporator tank at the end of a washing cycle by transferring the residual heat of the washing liquid to the heat exchanging medium in the evaporator tank via the refrigerant and/or or if for example the heat transfer to the washing liquid is no longer required or possible (e.g. no circulation, washing liquid maximally heated) then the residual heat of the heat pump may be deposited in the second operation mode in the evaporator tank so that this heat can be extracted in the next washing cycle for heating the circulated liquid.

In case the laundry treatment apparatus is a washer dryer, the following applies: In addition or as an alternative to the second operation mode described above, during a drying cycle of the washer dryer, the washing liquid may be cooled within the condenser and then used for the air humidity condensation in an air condensation unit arranged at or in the tub rear wall.

Preferably, the laundry treatment apparatus further comprises a washing liquid circulation unit which is adapted to circulate the washing liquid from the tub through the liquid passage of the condenser unit and back to the tub.

The circulation unit may comprise a circulation pump, a suction line connecting the tub to the inlet of the circulation pump and a return line connecting the outlet of the pump to the tub or to a fluid passage which is connected to the tub. In particular, the inlet of the suction line may be connected to a sump of the tub.

In addition or as an alternative, the outlet of the return line may be connected (a) to a spray nozzle that may be arranged at the tub or at a loading opening of the tub. The spray nozzle may be adapted to spray the circulated washing water towards the drum interior. The spray nozzle may be a shaped pipe where in particular the circulated liquid is released without water pressure. When herein a 'spray' is mentioned, the liquid exiting for example a nozzle may be pressurized (having e.g. a predefined directivity) or may be pressure-free. In particular, the spray nozzle introducing water into the tub is designed to change the shape of the liquid jet, e.g. by enlarging it as a sort of 'V or expanded spray. Or the outlet of the return line is connected (b) to the interior of a detergent drawer housing of the laundry treatment machine from where the circulated washing water may be guided back to drum interior. Or the outlet of the return line is connected (c) to a manifold of the laundry treatment machine which may be fluidly connected to the interior of the tub or the outlet of the return line is connected first to the drawer housing and then to the manifold. Preferably, a portion of the return line forms the liquid passage of the condenser unit.

The laundry treatment machine may be a washing machine or a washer-dryer having a first operation mode in which during at least a portion of a washing cycle the circulated washing liquid is heated, and/or having a second operation mode in which during at least a portion of a washing cycle the circulated (washing) liquid is cooled. In such a washing machine or washer-dryer and during the second operation mode cooling the washing liquid is used for de-icing the evaporator in e.g. the last washing cycle.

The manifold may for example be connected to the outlet of the drawer housing receiving therefrom a mixture of water and powdered or liquid washing agents. In addition or as an alternative the manifold may be connected to a tap water supply valve.

The circulation unit is effective in saving water when it resupplies the water circulated from the tub into drum (see below spray nozzle) as the water amount to be stored in tub is less as it is not required that the lower diameter of the drum is immersed in washing water having a respective water level.

The resupply via a spray nozzle (a) may be the most efficient use of detergent and water. This is a preferred solution for resupply of heated washing liquid for a washing machine. Preferably the spray nozzle is arranged at a bellows flexibly sealing between the loading opening (or porthole door) in the cabinet and the front side of the tub. In addition or as an alternative the spray nozzle may be arranged at an upper position with respect to the bellows or front opening in the tub. In addition or as an alternative the spray direction at the spray nozzle exit may be directed axially towards the rear side of the drum.

The suction line may be completely arranged in a bottom region of the cabinet. In addition or as an alternative the suction line may be located completely below the tub. The suction line is e.g. the shortest connection between circulation pump and the inlet to the condenser unit.

Preferably the laundry treatment machine further comprises a circulated washing water directing device adapted to direct the flow of circulated washing liquid that has passed the condenser unit selectively through a first return passage to the tub or through a second return passage to the tub. The first return passage may be the spray nozzle (a) and/or the first return passage may be selected and thus used during the first operation mode (washing cycle). The second return passage may include a passage through the interior of the drawer housing (b) and/or the manifold (c).

The directing device may be a switching and/or valve element. As an alternative, the directing device may be a flow diverter which depending on the flow speed of the circulated washing liquid directs the circulated washing liquid into

- a first outlet towards the first return passage (e.g. at a higher flow rate and/or to the spray nozzle (a)), or

- a second outlet towards the second return passage (e.g. at a lower flow rate and/or to the drawer housing (b), the manifold (c) and/or the spray nozzle.

Preferably the directing device is arranged downstream the detergent drawer housing.

Preferably, the return line is forming a siphon between the exit at the condenser outlet of the liquid passage and the outlet of the return line. Specifically, when the outlet of the return line is at the spray nozzle (a) (e.g. at an upper portion of the gasket at the loading opening).

Tray Element:

Preferably the top module comprises a tray element which provides a supporting structure of the top module, wherein the evaporator tank is integrated in the tray element. Preferably the tray element has one, two, three or four peripheral outer sides (side walls) that preferably extend downward from an upper plane of the tray element and/or form lateral side surfaces of the tray element.

Preferably the condenser unit is guided along the lateral outer wall of the evaporator tank along at least two sides of the evaporator tank and/or along an arc of at least 180° around the evaporator tank, and wherein the condenser unit is at least partially received in or at a receptacle along the path around the evaporator tank. Alternatively or additionally the condenser unit is guided along the peripheral outer sides of the tray element, namely along two, three or four peripheral outer sides. Preferably the condenser unit is arranged within the footprint (when seen from above in operational orientation) of the tray element. Preferably the tray element has lateral outer side walls at two, three or four sides and optionally the condenser unit is arranged at a vertical level to be located behind the sides of the tray level (when seen in side view).

By providing the condenser unit in an extended longitudinal shape the heat exchanging efficiency along the extended longitudinal shape is optimized while at the same time the overall volume of the condenser unit is reduced.

When 'winding' the condenser unit around the evaporator tank and/or along the periphery of the tray element the length of the extended condenser unit is stored within the tray element while the curvature of bending is reduced as compared e.g. to the bending into a spiral form.

Preferably, the outer lateral wall of the evaporator tank forms part of the receptacle for the condenser unit. The evaporator tank may be part of the receptacle and may stabilize/support the condenser unit. In addition or alternatively, the receptacle is only formed by lateral walls of the tray element. Additionally or alternatively the outer peripheral walls (see above) of the tray element form part of the receptacle for the condenser unit. Preferably at least at one, two, three or four sides of the tray element the condenser unit is received between the outer peripheral wall of the tray element and the outer lateral wall of the evaporator tank.

'Integrated in' means both that the evaporator tank may be formed as a single/ unitary element with the tray element (in a single piece construction) or as a separate element mounted to the tray element. Formed as a separate element, the evaporator tank may be formed in a single piece or may comprise several elements which are assembled, e.g. the bottom part of the evaporator tank and side walls. The ceiling part of the evaporator may be a cover, in particular a removable or non-removable evaporator tank cover for sealing the tank. E.g. the elements (evaporator tank and/or tray element) are monolithically formed elements produced for example by injection (plastic) molding or by deep drawing of a metal/plastic sheet.

Preferably, a switching element is mounted at or on the tray element, wherein the switching element is adapted to switch the refrigerant flow in the heat pump circuit between a forward and inverted flow direction. Preferably switching element is provided in tray element when compressor is also mounted at the tray element. This results in reduced circuitry. Preferably the evaporator tank has an upper bottom region which is located at a higher vertical level (e.g. forming the bottom of the upper region) than a lower bottom region which is located at the lowest vertical level (e.g. forming the bottom of the lower region), wherein in particular the lower bottom region is located at a side region of the tray element while the upper bottom region is located more centrally of the tray element when seen from above. Preferably the (left or right) side region and the center region relate to a perspective when seen in front view or rear view (in relation to an operational position of the top module mounted to a laundry treatment machine).

The tray element may comprise fixing and/or sealing elements for fixing and/or sealing a cover over the evaporator tank.

The receptacle (recess) preferably comprises one or a plurality of alignment and/or clamping elements for positioning and/or clamping the condenser unit within the receptacle or within the tray element. This stabilizes the condenser unit in its predefined position and form and/or secures the condenser unit to the tray element during manufacturing process and operation.

Preferably, the tray element has lateral outer walls on at least three sides thereof. This increases stability of the tray element and top module. The outer lateral walls of tray element preferably form outer lateral/peripheral walls of top module. The outer lateral walls of tray element may form part of the receptacle for receiving the condenser unit. Preferably, the receptacle (recess) has the shape or substantially the shape of the condenser unit when mounted at the top module. The outer lateral walls laterally protect condenser unit also during assembling process. More preferably the receptacle is formed by the outer lateral walls of the tray element and the outer walls of the evaporator tank.

Preferably, the tray element comprises a mounting bracket mounted to the tray element or being integral part of the tray element, wherein the mounting bracket is adapted to mount thereon a compressor of the heat pump.

A compressor mounted to the tray element is preferably part of the pre-assembled top module. The compressor is preferably mounted to the mounting bracket using vibration dampers. Mounting bracket is adapted to temporally secure the compressor thereto during transportation of a laundry treatment machine. Preferably a transport lock stationary fixes the compressor to the mounting bracket. Transport lock may be removed after transportation and before operation of the compressor. Preferably the tray element comprises a lock sensor detecting whether the compressor is in a locked or unlocked state at the mounting bracket. Detects e.g. whether the transport lock has been removed.

Preferably, the compressor, the evaporator, the condenser unit, the expansion device and all the refrigerant pipe connections are mounted in or on the top module, preferably in or on the tray element.

Each individual feature of the treatment machine can be combined with the top module as far as referring to the top module, in particular to the tray element, the evaporator tank and/or the compressor mounting, or any sub-group of features (e.g. any of the dependent claims) of the treatment machine can be individually combined with the top module. Vice versa any individual feature or sub-group of features of the top module or tray element can be combined with the treatment machine.

According to another configuration a method for operating a laundry treatment machine, in particular a laundry treatment machine as described above, is provided. The laundry treatment machine comprises: a heat pump having a compressor, an evaporator and a condenser, the condenser being adapted to heat washing liquid; and an evaporator tank housing at least a portion of the evaporator immersed in a heat exchanging medium, wherein the evaporator tank comprises an upper region accommodating a first portion of the evaporator and a lower region accommodating a second portion of the evaporator, and wherein the first and second portion of the evaporator are arranged at vertically different levels. The method comprises: introducing a refrigerant of the heat pump into the second portion of the evaporator at the lower region; and guiding the refrigerant from the second portion to the first portion of the evaporator at the upper region; wherein during the extraction of heat out of the heat exchanging medium the heat exchanging medium starts freezing on the surface of the first evaporator portion and continues during heat extraction to freeze on the surface of the second evaporator portion such that the freezing process within the evaporator tank is from the bottom up.

The freezing 'bottom up' not necessarily means that the lowest point on the evaporator is surface-freezing first and/or the heat exchanging medium in the lower region is first completely frozen before the surface-freezing at the first portion or upper region starts. It means that the freezing of surfaces or the speed of surface freezing at the second evaporator portion in the lower region starts and is faster there than the surface freezing in the upper region at the first portion. The bulk of ice is first formed in the lower portion and ice formation moves (gradually) upwards with continuing time of the heat extracting process.

Preferably the refrigerant is guided out of the evaporator tank downstream of the second portion. Preferably a gaseous volume is provided within the evaporator tank above the heat exchanging medium for receiving the water displaced by the expanding ice.

According to another configuration a method for operating a laundry treatment machine, in particular a laundry treatment machine as described above, is provided. The laundry treatment comprises: a heat pump having a compressor, an evaporator and a condenser, the condenser being adapted to heat washing liquid, an evaporator tank housing the evaporator or at least a portion of the evaporator, wherein the evaporator tank is a tank for storing a heat exchanging medium, a top module, wherein when the top module is mounted at the laundry treatment machine it is forming part of the cabinet as a top and wherein the top module comprises the evaporator tank and the evaporator, wherein the evaporator tank comprises a first and a second container chamber, wherein the first container chamber houses the evaporator or at least a portion of the evaporator and permanently stores the heat exchanging medium, and wherein the second container chamber is a flow through-tank chamber comprising an inlet and an outlet, wherein the second container chamber is in heat contact with the heat exchanging medium in the first container chamber and wherein washing liquid drained from the tub is passed through the second container chamber via the inlet and outlet; wherein an inlet of a circulation pump is connected to the tub or the sump of the tub and an outlet of the circulation pump is connected to the inlet of the second container chamber; wherein the method comprises: circulating the washing liquid with the circulation pump through the second container chamber; and reintroducing the circulated washing liquid into the tub or the sump.

By circulating the washing liquid through the second container chamber heat of the washing liquid is transferred to the heat exchanging medium stored in the first container chamber, and therefore, to melt the frozen heat exchanging medium (e.g. ice) formed in the first container chamber. Thus frozen medium that has formed in the tank (i.e. first container chamber) can be dissolved by the circulation of the washing liquid through the second container chamber which results in an improved operation efficiency of the laundry treatment machine. Preferably, the method further comprises: operating the drain pump for draining washing liquid out of the laundry treatment machine in one or more periods immediately before operating the circulation pump; and/or operating the drain pump partially during periods of operating the circulation pump. "Immediately before" means in a time period of 0-60 secs, preferably 0-20 secs or 0-5 secs before operating the circulation pump (mixing pump).

Preferably, only a portion of the washing liquid is drained out in order to be able to feed new warmer washing liquid from the tub or sump into the cold washing liquid. This ensures that the cold washing liquid exiting the second container chamber is reheated by mixing it with new warm water from the tub.

Preferably, the washing liquid exiting the second container chamber is guided to the sump. This ensures that the laundry stored in the drum does not come in contact with the cold water exiting the second container chamber and therefore ensures that the laundry and the drum does not cool down.

Preferably the chamber circulation pump (mixing pump) is operated before operating the drain pump or at least partially simultaneously with operating the drain pump. E.g. when the chamber circulation pump is fluidly connected to the sump and when then or simultaneously the drain pump is operated, 'fresh' washing liquid is extracted by the drain pump via the sump from the tub such that when the chamber circulation pump is also fluidly connected to the sump the chamber circulation pump (mixing pump) at least partially extracts washing liquid freshly provided from the tub by the activity of the drain pump. A closed loop circulation of the 'same' washing liquid from the sump to the evaporator tank is avoided such that fresh and warmer washing liquid is fed into the circulation to the evaporator tank, in particular the second container chamber.

Preferably the washing machine comprises a control unit that is adapted to control the operation of the chamber circulation pump as described herein and in particular as described in this paragraph and in the preceding paragraphs.

Preferably, a drain pump is provided for draining all or the remaining washing liquid from the sump and tub after the circulation pump has been operated. Operating the drain pump after the circulation has been operated is preferably used for draining the washing liquid which remains in the laundry treatment machine after circulation of the washing liquid through the second container chamber has been finished. Each individual feature of the treatment machine and/or the top module can be combined with the method, or any sub-group of features (e.g. any of the dependent claims) of the treatment machine and/or top module (e.g. tray element) can be individually combined with the method. Vice versa any individual feature or sub-group of features of the method can be combined with the treatment machine and/or the top module (e.g. tray element) as a functional feature of the machine.

Any feature disclosed herein (for the above embodiments and/or configurations and from the below described detailed embodiments and modifications) can be combined with the claimed subject individually or in any sub -combination.

Reference is made in detail to preferred embodiments of the invention, examples of which are illustrated in the accompanying figures, which show:

Fig. 1 a perspective outer appearance of a washing machine with a top module,

Fig. 2 a front view of the washing machine of Fig. 1,

Fig. 3 a top view of the washing machine of Fig. 1,

Fig. 4 a perspective view of the washing machine of Fig. 1 without the casing,

Fig. 5 another perspective view of the washing machine of Fig. 4,

Fig. 6 a detailed perspective view of the pump arrangement of Fig. 5,

Fig. 7 a perspective rear view of the washing machine of Fig. 1 without the top wall,

Fig. 8 a perspective view of the top module of Fig. 5 with a partial section,

Fig. 9 a bottom view of the top module of Fig. 5,

Fig. 10 a perspective view from below of the top module of Fig. 9, Fig. 11 a perspective view from above of the top module of Fig. 10 without the evaporator tank cover,

Fig. 12 a perspective view from below of the top module of Fig. 11 without the tray element,

Fig. 13 a bottom view of the top module of Fig. 12 without the compressor mounting bracket,

Fig. 14 a top view of the top module of Fig. 8 with an intersection line A- A,

Fig. 15 a sectional view of the top module according to the intersection line A- A of Fig. 14,

Fig. 16 a perspective view from above of the top module of Fig. 11 with a microchannel arrangement,

Fig. 17A a schematic sectional view of a first position of the microchannel arrangement with a different evaporator tank form of Fig. 16,

Fig. 17B a schematic sectional view of a position of two microchannel arrangements with another evaporator tank form of Fig. 16,

Fig. 17C a schematic sectional view of another position of three microchannel arrangements with another evaporator tank form of Fig. 16,

Fig. 18 a perspective view of the water inlet portion of the tube-in-tube condenser of Fig. 13,

Fig. 19 a perspective view of the water inlet portion of the condenser of Fig. 13 with microchannels,

Fig. 20 a perspective view of the washing machine of Fig. 1 without the front and top wall and with another configuration of the top module and the compressor,

Fig. 21 a perspective view of the top module and the compressor of Fig. 20 with a partial section of the tray element, Fig. 22 a bottom view of the top module and the compressor of Fig. 21,

Fig. 23 a detailed perspective view of the switching valve of Fig. 21,

Fig. 24 a perspective view of the washing machine of Fig. 20 with a microchannel arrangement,

Fig. 25 a perspective view of the washing machine of Fig. 20 with another configuration of the top module,

Fig. 26 a top view of the top module of Fig. 25 with an intersection line A- A,

Fig. 27 a sectional view of the top module according to the intersection line A- A of

Fig. 26,

Fig. 28 an exploded view of the top module of Fig. 25,

Fig. 29 a perspective view from below of the top module and the compressor of Fig. 25,

Fig. 30 another perspective view from above of the top module and compressor of Fig. 29 with partial section of the tray element,

Fig. 31 a perspective view of the washing machine of Fig. 25 with a microchannel arrangement,

Fig. 32 a perspective view of another washing machine with a top module,

Fig. 33 an exploded view of the washing machine of Fig. 32 without the front and top wall,

Fig. 34 a detailed perspective view of the pump arrangement of Fig. 32,

Fig. 35 a front view of the upper portion of the washing machine of Fig. 32 without the front wall, Fig. 36 an exploded view of the top module and the compressor of Fig. 33,

Fig. 37 an exploded view of the top module and the compressor of Fig. 33 in another perspective view,

Fig. 38 a perspective view of the top module and the evaporator of Fig. 33 with partial section of the tray element,

Fig. 39 a top view of the top module of Fig. 33 with an intersection line A- A,

Fig. 40 a sectional view of the top module according to the intersection line A- A of

Fig. 39,

Fig. 41 a perspective view of the evaporator of Fig. 40,

Fig. 41 A an exploded view of the tray element, the evaporator tank and the evaporator tank cover of Fig. 40,

Fig. 4 IB a perspective view of the evaporator of Fig. 40 with mounting elements for the evaporator,

Fig. 41C an exploded view of the evaporator of Fig. 4 IB,

Fig. 4 ID a perspective view of the evaporator with another shape,

Fig. 4 IE a perspective view of the evaporator of Fig. 4 ID in an assembled state within the tray element shown in Fig. 40,

Fig. 42 a perspective view of the washing machine of Fig. 32 without the front and top wall and with another configuration of the circulation pump,

Fig. 43 a detailed perspective view of the pump arrangement of Fig. 42,

Fig. 44 a front view of the washing machine of Fig. 42,

Fig. 45 a perspective view of the washing machine of Fig. 42 without the side walls and the rear wall and with an evaporator tank water regeneration arrangement, Fig. 46 a detailed perspective view of the pump arrangement of Fig. 45,

Fig. 46 A a perspective view of the compressor, the pump arrangement and the top module of the washing machine of Fig. 45 without the evaporator tank water regeneration arrangement and another arrangement of the jet pump,

Fig. 46B a perspective view of the washing machine of Fig. 45 without the evaporator tank water regeneration arrangement and with another configuration of the jet pump and the condenser,

Fig. 46C a perspective view of the washing machine of Fig. 46B with another arrangement of the condenser and a switching valve,

Fig. 47 an exploded view of the compressor, the pump arrangement and the top module of Fig. 45,

Fig. 48 a perspective view of the top module of Fig. 45 without the evaporator tank cover,

Fig. 49 a perspective view from below of the evaporator tank cover of Fig. 45,

Fig. 50 a perspective view of the top module of Fig. 48 with the fixing elements and the separation wall of the bottom of the evaporator tank cover when mounted,

Fig. 51 A a perspective view of the washing machine of Fig. 46C in an assembled state without the front wall, rear wall and side walls and with an evaporator tank water regeneration arrangement,

Fig. 5 IB a perspective view of the washing machine of Fig. 51 A with another configuration of the evaporator tank water regeneration arrangement,

Fig. 52 an exploded view of the tray element of Figs. 51 A and 5 IB,

Fig. 53 a sectional view of the pipe section for guiding water within the evaporator tank of Fig. 52, Fig. 54 a sectional perspective view of the separation wall and the pipe sections of the evaporator tank of Fig. 52,

Fig. 55A a perspective view of the upper half of the washing machine of Fig. 5 IB with another arrangement of the pipe sections of the evaporator tank,

Fig. 55B a sectional view of the pipe sections of Fig. 55A,

Fig. 55C a perspective view of Fig. 55A with another arrangement of the pipe sections of the evaporator tank,

Fig. 55D a sectional view of Fig. 55A with another arrangement of the pipe sections of the evaporator tank,

Fig. 55E a perspective view of Fig. 55C with another arrangement of the pipe sections of the evaporator tank,

Fig. 55F a sectional view of the pipe sections of Fig. 55E,

Fig. 56 A a perspective view of Fig. 47 with another configuration of the tray element,

Fig. 56B a detailed sectional view of the evaporator tank inlet and outlet portion,

Fig. 57 a schematic diagram of the heating and cooling process during circulation of the washing liquid in a washing machine, and

Fig. 58 a perspective view of a washer dryer without the tray element and the casing.

Fig. 1 shows a perspective outer appearance of an exemplary washing machine 2 with a top module 5. Figs. 2 and 3 show a front and a top view of the washing machine 2 according to Fig. 1. As shown in Fig. 1, the washing machine 2 has a cabinet 4 comprising two side walls 10, a front wall 8, a bottom (plate or shell) 56 (see: Fig. 4), a rear wall 24 (see also: Fig. 7) and a top wall 9. According to the embodiment, the top wall 9 is mounted above the top module 5 and is preferably forming a work top. At the front wall 8 a loading opening 16 which is closed by a door 18 is provided for loading laundry into the washing machine 2. The upper region of the machine front face comprises a detergent drawer 12 with a handle 13 which is preferably arranged at the left side of the upper region. The detergent drawer 12 is used for storing and in particular for providing washing agents (e.g. detergent, softener, conditioner, auto dosing or other treatment agents) during washing cycles. The washing machine 2 further has a control panel 14 preferably arranged at the middle and/or right side of the upper region of the machine front face. The control panel 14 preferably comprises a display for displaying information about the washing program (e.g. energy consumption, duration of the washing cycle and the like) and an input device. In this case, the input device is a control knob provided for selecting between different washing programs. The knob is preferably arranged between the control panel 14 and the detergent drawer 12.

The front wall 8 may comprise an air inlet opening 20 which may be arranged near the center. A cover for service opening 22 may be provided e.g. on the right side of the lower region of the front wall 8. The air inlet opening 20 enables air entering the interior of the washing machine 2. The air passing through the inlet opening 20 may be provided for cooling the compressor and further electronic components inside the washing machine 2 with air.

The washing machine 2 shown in Figs. 1 to 3 is a front-loading machine having preferably a horizontal drum rotation axis, but in alternative embodiments the drum may be inclined relative to the horizontal and vertical directions.

Generally in the following, the refrigerant flow direction 94 and the washing liquid flow direction 96 are indicated by arrows in some of the following Figures (see: Figs. 9, 22, 36, 47). Therefore, a dashed arrow defines the washing liquid flow direction 59 and a filled arrow the refrigerant flow direction 43. These definitions for the flow directions are valid for the Figures herein.

Fig. 4 is a perspective view of the washing machine of Fig. 1 without the casing and Fig. 5 shows another perspective view of the washing machine of Fig. 4. As shown in Fig. 4, a tub 58 and a drum 60 rotatably arranged in the tub 58 and in which laundry is received, are arranged inside the cabinet 4 (not shown). The tub 58 may be suspended by spring dampers 30 and/or a balance weight 28 for stabilizing the tub 58 and the drum 60. For preventing water from entering the washing machine 2, except the tub 58 and drum 60, a bellow 62 may be mounted to the tub 58 or to the tub 58 and to the front wall 8 (not shown). Further, a detergent drawer housing 12a for receiving the drawer 12 is arranged in the upper region of the washing machine 2. The detergent drawer housing 12a is preferably arranged on the left side of the upper region of the washing machine 2, in particular below the top module 5. The detergent drawer 12 is inserted into the detergent drawer housing 12a. The structure of the top module 5 which is mounted on top of the cabinet 4 corresponds to the structure of the top module 5 described further below according to Figs. 8 to 16. The top module 5 may be mounted on the cabinet 4 by fastener elements, e.g. by screws or snap-in elements. The conduits of the top module 5 are connected to the conduits of the washing machine 2 by a fourth water circulation section 64d connected to a washing liquid condenser outlet 84 and a second water circulation section 64b is connected to a washing liquid condenser inlet 82 (see: Fig. 9).

As shown in Fig. 4, the top module 5 comprises components of a heat pump. The heat pump comprises a compressor 36, a condenser 81 and an evaporator 102 (further described according to Fig. 9). The top module 5 further comprises a tray element 6 which is mounted on the top of the washing machine 2, and which can be mechanically connected to the two side walls 10, the front wall 8 and the rear wall 24 of the washing machine 2. As shown in Fig. 5 the tray element 6 preferably has lateral side walls 7 along the periphery of the tray element and/or downward from an upper plane/plate of the tray element.

The tray element 6 may comprise an evaporator tank 100 for receiving a heat exchanging medium (e.g. water) and an evaporator 102 (see: Fig. 11). Preferably, the evaporator tank 100 and the tray element 6 are formed in a single piece, for example by injection molding of plastic or by deep drawing of a metal sheet. The evaporator tank 100 is preferably covered by an evaporator tank cover 32. Preferably, a gasket is arranged between the evaporator tank cover 32 and the evaporator tank 100. The evaporator tank cover 32a may be mounted to the evaporator tank 100 or the tray element 6 detachable e.g. by screws or non-detachable e.g. by welding or gluing. The evaporator tank cover 32 may comprise seats and/or ribs 34 at the outer side for receiving a thermo-insulating material. The tray element 6 may further comprise an opening for receiving the compressor 36. The opening and thus the compressor 36 is preferably arranged next to the evaporator tank 100.

As shown in detail in Fig. 8, a mounting bracket 90 for receiving the compressor 36 may be arranged within the opening. The mounting bracket 90 extends from the surface down into the interior of the washing machine 2 and preferably forms a U- shape from the side (parallel to the rotation axis of the compressor 36). The mounting bracket 90 may be a separate element or may be formed in a single piece with the tray element 6. The compressor 36 is preferably mounted on the mounting bracket 90 by damping elements (vibration dampers) 92 for damping vibrations.

Summarizing, the tray element 6 is adapted to contain a liquid, in particular a heat exchanging medium, and to support components such as the evaporator 102, the condenser 81 and/or the compressor 36. Preferably the tray element is mechanically connected to or supports parts of the washing machine cabinet 4, in particular the side walls 10, the front wall 8 and the rear wall 24, as a part of the frame structure.

As further shown in Figs. 4 and 5, the washing liquid supplied to the tub 58 of the washing machine 2 is further used in a washing liquid circulation unit 64 used for saving water. In the washing liquid circulation unit 64, the washing liquid is guided through a first, second, third and fourth water circulation section. The first water circulation section 64a extends between an outlet of the tub 58 (e.g. via a sump, see: Fig. 57) and an inlet 66a of a circulation pump (jet pump) 66, the second water circulation section 64b between an outlet 66b of the circulation pump 66 and the washing liquid condenser inlet 82 (see: Fig. 9), a third water circulation section 64c between the washing liquid condenser inlet 82 and outlet 84 (see: Figs. 9 and 18), and the fourth water circulation section 64d between the washing liquid condenser outlet 84 and an water inlet 65 (e.g. a nozzle) into tub 58.

The circulation pump 66 is preferably arranged in the bottom region of the washing machine 2, e.g. in the lower left corner at the front of the washing machine 2. The circulation pump 66 is used to drain washing liquid (during a washing phase) or water (during a rinsing phase) from the tub outlet 74 and recirculate the liquid to the upper part of the tub 58 where the liquid is introduced into the tub 58 by the water inlet 65. The water inlet 65 into the tub may be a nozzle preferably arranged at the loading opening 16, bellow 62 or at the tub 58 from where the washing liquid flows into the tub 58. As shown in Fig. 4, at least a portion of the second water circulation section 64b may extend along a side wall or a corner of the washing machine 2, e.g. at the left side of the washing machine 2 parallel to the side wall 10 (not shown).

The washing liquid is circulated in the washing liquid circulation unit 64 through the water circulation sections 64a-d during a washing cycle and is heated by the heated refrigerant during passing the condenser 81 (see Fig. 9). A drum drive arrangement (not shown) may comprise a motor for driving the drum 60 and optionally a torque transmission element (e.g. a belt) connecting the motor and the drum 60 for driving the drum 60. The motor may be arranged at the rotation axis of the drum 60 or may be arranged under the rear region of the tub 58. The drum drive arrangement is applicable for all embodiments of washing machines disclosed herein. Alternatively a drum drive motor is mounted on the backside of the tub (not shown).

Fig. 6 shows a detailed perspective view of the pump arrangement of Figs. 4 and 5. As shown in Fig. 6, the washing machine 2 may comprise a drain pump 72, which is connected to the tub outlet 74 (e.g. via the sump 140, in particular from the drain manifold which is arranged at the lower part of the sump 140, see: Fig. 57) may be connected to a water drain 70 which is used for draining the washing liquid at the end of a washing cycle out of the washing machine 2. Herein 'washing liquid' comprises water with resolved treatment agent, water used e.g. for rinsing and other liquids used during a washing and/or drying cycle. The drain pump 72 is preferably arranged in the bottom region of the washing machine, e.g. in the lower right comer at the front of the washing machine 2. The washing machine 2 may comprise a filter/service opening 68 preferably for removing the fluff which accumulates during washing and/or for performing service operations. The filter/service opening 68 is preferably arranged in the lower right corner at the front of the washing machine 2.

The washing machine 2 may have a mixing pump 76 which may be connected to the tub outlet 74, in particular to the drain manifold which is arranged at the lower part of the sump 140, and which drains water and detergent from the bottom of the tub (e.g. the sump of the tub 58) at the beginning of a washing cycle after detergent has been introduced into the tub 58 and re-send the water and detergent to the tub 58, e.g. to the sump of the tub or in particular to the tub 58 below a water heater (not shown, see: Fig. 57), by a return line 77. Thereby, the mixture and dissolution of the detergent in the water can be improved and accelerated. The mixing pump 76 is preferably arranged in the bottom region of the washing machine, e.g. in the lower right corner at the front of the washing machine 2. Preferably, the drain pump 72 and the mixing pump 76 are integrated in a pump group. Preferably a filter of the filter opening 68 is provided upstream of the mixing and drain circuit.

A water supply unit (not shown) connected to the detergent drawer housing 12a may provide fresh water from the outside of the washing machine 2 to flush the detergent from the detergent drawer 12 through the water supply and the water inlet 65 into the tub 58.

Fig. 7 is a perspective rear view of the washing machine of Fig. 1 without the top wall. The water drain 70 shown in Figs. 4 and 5 is preferably guided through the rear wall 24 for connecting the water drain 70 to the waste water at the installation location.

Preferably, the water drain 70 is guided through the rear wall 24 at the upper left corner (when the washing machine is seen from the rear side). With regard to transportation of the washing machine 2, the rear wall 24 may also comprise at least one transport lock

80 for stationary fixing the compressor 36 to the mounting bracket 90 (see: Fig. 8) and/or at least one opening for a tub transport lock 79 for stationary fixing the tub. Preferably, the washing machine 2 comprises three transport locks 79 for the tub and one for the compressor 36.

Fig. 9 shows a bottom view of the top module 6 of Fig. 5, Fig. 10 a perspective view from below of the top module 6 of Fig. 9 and Fig. I l a perspective view from above of the top module 6 of Fig. 10 without the evaporator tank cover 32.

As already mentioned above, the heat pump comprises the compressor 36, the condenser 81 and the evaporator 102. As shown in Figs. 9 to 11, the condenser 81 may be arranged in a recess provided on an underside of the tray element 6 (a surface of the tray element 6 facing the tub 58 of the washing machine when mounted) that may form a channel extending along at least one side of the evaporator tank 100, preferably along at least two or three sides of the evaporator tank. The evaporator 102 and the condenser

81 may be arranged in the same plane and the condenser 81 is guided at least partially around the evaporator 102. In an alternative configuration the condenser 81 extends along one side, two sides, three sides or four sides of the evaporator tank 100.

Preferably and as shown in the configuration of Fig. 9 the condenser 81 is provided along four peripheral sides of the tray element, wherein it is provided partially at a first and fourth side thereof. Alternatively it is provided along at least two or three peripheral sides of the tray element. In any case the condenser unit 81 is located within the base area of the tray element when seen from above (with respect to an operational orientation of the top module/laundry treatment machine).

The condenser 81 comprises the washing liquid condenser inlet 82 and outlet 84 and a refrigerant condenser inlet 86 and outlet 88. The condenser 81 is used for heating the washing liquid within a washing liquid circulation unit 64. As shown in Fig. 11, the evaporator tank 100 comprises the evaporator 102 and may form with the evaporator tank cover 32 a closed tank for permanently storing a heat exchanging medium. The evaporator 102 is surrounded by (immersed in) the heat exchanging medium stored in the evaporator tank 100 for exchanging heat between the refrigerant flowing through the evaporator 102 and the heat exchanging medium. The evaporator inlet 104 and outlet 106 may be arranged at the bottom of the evaporator tank 100, e.g. near the front wall 8 of the washing machine 2. Preferably the evaporator inlet 104 and outlet 106 are arranged at the top of the evaporator tank 100, in particular at the evaporator tank cover 32. In this preferred configuration, the refrigerant is fed into and out of the evaporator tank 100 from above.

As shown in Figs. 9 and 10, the evaporator tank 100 may comprise an upper region 100a and a lower region 100b connected to the upper region 100a. The lower region 100b and the upper region 100a form a continuously single evaporator tank 100. As shown in Fig. 9, the lower region 100b is arranged vertically below the upper region 100a and the horizontal cross-section area of the lower region 100b is less than the horizontal cross-section area of the upper region 100a. In particular the tank 2 comprises a step between the lower region 100b and the upper region 100a when seen in the vertical cross-sectional view of Fig. 15. In this case, the lower region 100b has a vertical or substantially vertical surface connecting the bottom of the upper region 100a with the bottom of the lower region 100b. Alternatively, the vertical surface of the lower region 100b may also be an inclined and/or rounded surface connecting the upper region 100a with the lower region 100b. Further examples for the cross-sectional shape of the evaporator tank 100 are shown in Figs. 17A to 17C.

As shown in Fig. 11 in connection with Figs. 14 and 15, wherein Fig. 14 is a top view of the top module of Fig. 8 with an intersection line A- A and Fig. 15 is a sectional view of the top module 6 according to the intersection line A-A of Fig. 14, the tube forming the evaporator 102 in the tank 100 is preferably extending in several regions within the top module 6. In particular, a first portion of the evaporator 102a is accommodated in the upper region 100a (volume of region indicated by dotted line) and a second portion of the evaporator 102b is accommodated in the lower region 100b (volume of region indicated by dotted line) wherein the first and second portions 102a, 102b are arranged at vertically different levels. As further shown in Figs. 13, 15, the first and second portion 102a, 102b are arranged in meandering form in the evaporator tank 100. Preferably, the first and second portion 102a, 102b of the evaporator extend horizontally in the lower region 100b and the upper region 100a, respectively (refrigerant pipes forming two horizontal planes one above the other). The windings of the meandering evaporator pipe in the upper region 100a and the windings of the meandering evaporator pipe in the lower region 100b may be crossed to each other, e.g. the meanders of the upper region 100a and these of lower region 100b are arranged each in a plane and the orientation is crossed e.g. under 90°.

Further Fig. 15 shows that preferably the condenser unit 81 is guided along the inner side of the peripheral side walls 7 of the tray element. Preferably the side walls 7 form part of a receptacle for receiving the condenser unit 81 thereby protecting and/or supporting the condenser unit within the tray element (top module) during assembling. Further preferred the condenser unit is arranged at a vertical level (in operational orientation) between the evaporator tank and the peripheral side walls 7 - at least along sides of evaporator tank where no further components of the tray element are arranged. E.g. the unit is positioned between the peripheral side walls 7 and the outer lateral wall of the evaporator tank 100 at one, two or three sides of the evaporator tank. This arrangement of the condenser unit is applicable also in other examples disclosed herein - compare e.g. Fig. 27 and 38.

Alternatively, the evaporator 102 is an evaporator block or an evaporator battery which is oriented inclined to a horizontal plane such that a portion of the evaporator block or battery is positioned in the upper region 100a and forms the first portion of the evaporator and another portion of the evaporator block or battery is positioned in the lower region 100b and forms the second portion of the evaporator (see Fig. 17A, 27).

Preferably, the evaporator tank 100 is only partially filled with the heat exchanging medium and a gaseous volume 114 (e.g. air) is provided above the upper region 100a within the inner space of the evaporator tank 100 above the heat exchanging medium. When the heat exchanging medium in the evaporator tank 100 freezes, the gaseous volume allows the ice to expand freely. The expansion of the ice as compared to the corresponding water amount displaces the still liquid water upwards to occupy the volume of the gaseous volume which is compressed (higher compressibility as compared to water) or the gas is itself displaced in case of an open evaporator tank (see below examples). Thus, there is no pressure by ice on the bottom of the tank and the tank is not damaged by the expansion of the ice.

As further shown in Fig. 11, the first and second portion of the evaporator 102a, 102b preferably have a meandering structure extending at one horizontal level parallel to the bottom of the evaporator tank 100, respectively. The straight sections of the meandering structure of the evaporator 102 may be arranged in any angle to the side walls of the evaporator tank 100. Preferably the straight sections of the meandering structure of the evaporator 102 are arranged parallel to the edges of the side walls of the evaporator tank 100. The tubes of the evaporator 102 may have an external diameter in the range of 5 mm and 7 mm, 6 mm and 8 mm or 7 mm and 9 mm. Preferably the tubes have an external diameter of 7 mm. Each bend of the evaporator 102 may have a curvature radius between 12 mm and 16 mm, 14 mm and 18 mm or 16 mm and 20 mm, but preferably the curvature radius is 15 mm. The tubes forming the evaporator 102 may have a pitch between 24 mm and 28 mm, 28 mm and 32 mm or 32 mm and 36 mm, but preferably the pitch is 30 mm.

Fig. 12 is a perspective view from below of the top module of Fig. 11 without the tray element 6 and Fig. 13 is a bottom view of the top module of Fig. 12 without the compressor mounting bracket 90. A refrigerant circulation circuit 42 comprises a first, second, third, fourth, fifth and sixth refrigerant circuit section. A first refrigerant circuit section 44a extends between the refrigerant condenser outlet 88 and the evaporator inlet 104, a second refrigerant circuit section 46a between the evaporator outlet 106 and a first inlet 78a of a switching element (switching valve) 78 (refrigerant flow changing device), a third refrigerant circuit section 48a between the a first outlet 79a of the switching valve 78 and a compressor inlet 110 (see Fig. 11), a fourth refrigerant circuit section 50a between a compressor outlet 112 and a second inlet 78b of the switching valve 78, a fifth refrigerant circuit section 52a between a second outlet 79b of the switching valve 78 and the refrigerant condenser inlet 86, and a sixth refrigerant circuit section 54a between the refrigerant condenser inlet 86 and outlet 88 which in this example are the inlet and outlet of an outer tube 120 of the condenser (see Fig. 18). The first refrigerant circuit section 44a may be arranged at the underside of the evaporator tank 38 and may comprise an expansion device 40 for controlling the amount of refrigerant released into the evaporator 102.

The refrigerant enters the evaporator 102 in the evaporator tank 100 at the lower region 100b of the evaporator tank 100, flows through the second portion of the evaporator 102b arranged in the lower region 100b and then through the first portion of the evaporator 102a arranged in the upper region 100a of the tank and exits the evaporator 102 in the evaporator tank 100 from the first portion in the upper region 100a.

The switching valve 78 described above may be arranged at the top of the washing machine 2. Preferably the switching valve 78 is arranged within the tray element 6, in particular within or below the opening in which the compressor 36 is arranged. Most preferably, the switching valve 78 is positioned horizontally, in particular parallel to the rotation axis of the compressor 36.

The switching valve 78 may be a valve that only guides the refrigerant from the first inlet 78a to the first outlet 79a and from the second inlet 78b to the second outlet 79b. Preferably, the switching valve 78 is configured to change the refrigerant flow direction within the refrigerant circulation circuit 42. The switching valve 78 described above is optional. In a configuration without the switching valve 78, the refrigerant of the second refrigerant circuit section 46a may be guided from the evaporator outlet 106 to the compressor inlet 110 and from the compressor outlet 112 to the condenser inlet 86.

The features described above relating to the switching valve 78 are applicable for all embodiments of washing machines disclosed herein.

Fig. 16 shows a perspective view from above of the top module of Fig. 11 with a microchannel arrangement. The differences between the top module of Fig. 16 and the top module of Figs. 4 to 15 are outlined in the following. Otherwise the elements and functions as described above and below with respect to the other elements correspondingly also apply individually, in subgroups or as a functional group to the embodiment of Fig 16.

As shown in Fig. 16, the tray element 6 is identical to the tray element described above according to Figs. 4 to 15, except the evaporator 102. Instead of an evaporator formed by pipes, the tray element 6 comprises a microchannel arrangement 116 positioned within the evaporator tank 100. The microchannel arrangement 116 may comprise an inlet distribution channel 116b, several microchannel elements 116a each connected with one end to the inlet distribution channel 116b and an outlet collection channel 116c connected with each free end of the microchannel elements 116a. The refrigerant enters and exits the microchannel arrangement 116, in particular the inlet distribution channel 116b and the outlet collection channel 116c, through the evaporator inlet 104 and the evaporator outlet 106 (in particular supplied which refrigerant by a first refrigerant circuit section 44b and a second refrigerant circuit section 46b) which are preferably arranged at the evaporator tank cover 32 (not shown). Preferably, the evaporator tank inlet 104 is provided on the right side, in particular the front right corner, and the evaporator tank outlet 106 on the left side, in particular on the rear left comer, of the evaporator tank cover (when seen the washing machine in front view). The refrigerant is distributed by the inlet distribution channel 116b and is guided through the microchannel elements 116a to the outlet collection channel 116c. Each of the microchannel elements 116a comprises several microchannels arranged above each other. The microchannel arrangement 116a has a higher heat exchange efficiency than an evaporator formed with pipes since the heat exchanging surface is increased by the microchannels in each microchannel element 116a.

Fig. 17A-C are schematic sectional views of different positions and numbers of the microchannel arrangement of Fig. 16 combined with different evaporator tank forms. The sectional views correspond to views when seen the tank in front view of the washing machine.

Fig. 17A shows an evaporator tank 100 with the upper region 100a and the lower region 100b wherein the bottom surface is inclined. The microchannel arrangement 116 is arranged obliquely such that the inlet distribution channel 116b is positioned in the lower region 100b (volume of region indicated by dotted line) and the outlet collection channel 100c in the upper region 100a (volume of region indicated by dotted line) of the tank 100. Thus, the microchannels of the microchannel elements 116a extend obliquely from the upper region 100a to the lower region 100b. Preferably the microchannel elements 116a are parallel to the inclined bottom surface of the evaporator tank 100.

Fig. 17B shows an evaporator tank 100 with a form as already described according to Figs. 9 and 10. The horizontal cross-section area of the lower region 100b (volume of region indicated by dotted line) is smaller than the horizontal cross-section area of the upper region 100a (volume of region indicated by dotted line) and therefore the vertical cross-sections of the lower region 100b and the upper region 100a form a step between the upper and lower region 100a, 100b. A first microchannel arrangement 116 may be arranged in the upper region 100a and/or a second microchannel arrangement 116 may be arranged in the lower region 100b of the tank 100. The microchannel arrangement of the lower region 100b is smaller than the microchannel arrangement of the upper region 100a (in particular in respect of the dimensions in the horizontal plane). As further shown in Fig. 17B, the microchannel arrangements are positioned at vertically different levels, wherein the microchannel arrangements are positioned horizontally, parallel to the bottom surface of the tank 100. Preferably, the microchannel arrangements 116 are positioned above each other or may be at least partially offset from each other. Fig. 17C shows an evaporator tank which has two steps compared to the tank of Fig. 17B which comprises only one step. As shown in Fig. 17C, the evaporator tank 100 comprises at least one intermediate region 100c (volume of region indicated by dotted line) located between the upper and lower region 100a, 100b and accommodating at least one microchannel arrangement 116. As shown in Fig. 17C, each region, upper, intermediate and lower region lOOa-c may comprise a microchannel arrangement 116 positioned at vertically different levels. Alternatively, the evaporator tank 100 may comprise two, three, four or more intermediate regions, wherein each region comprises at least one microchannel arrangement 116.

It should be clear that instead of a microchannel arrangement as described according to Figs. 17A-C an evaporator formed by pipes may also be used in the evaporator tanks described in Figs. 17A-C. E.g. with respect to Figs. 17B and 17C, an evaporator formed with pipes in two (three) vertically different horizontal planes may be provided in the tank 100. The pipes of the evaporator arranged in different horizontal levels may have a different orientation between the horizontal levels, i.e. the pipes of one horizontal level may not be parallel to the pipes of another level. Thus, all features described according to Figs. 17A-C, in particular regarding the position of the evaporator and the evaporator form, are also valid for evaporators formed by pipes regarding all embodiments disclosed herein.

Fig. 18 is a perspective view of the water inlet portion of the tube-in-tube condenser of Fig. 13. The condenser 81 may be a tube-in-tube condenser consisting of an inner tube 118 for guiding the washing liquid, an outer tube 120 for guiding the refrigerant and an insulation layer 122 (see Fig. 15) when starting from the inside of the condenser 81. The flow direction of the refrigerant and the washing liquid within the condenser 81 may be opposite to each other for improving the heat exchange. The condenser 81 further comprises the washing liquid condenser inlet 82 and the refrigerant outlet 88. Preferably, a connection element 126 comprising the refrigerant outlet 88 is provided at the water inlet portion of the condenser 81 and which is adapted to guide refrigerant through the outer tube 120. More preferably, an inner surface of a first end portion 126a of the connection element is connected to the outer surface of the inner tube 118 of the condenser and an inner surface of a second portion 126b of the connection element is connected to the outer surface of the outer tube 120 of the condenser.

Fig. 19 shows a perspective view of the water inlet portion of the condenser of Fig. 13 with microchannels. The condenser 81a of Fig. 19 is similar to the condenser 81 of Fig. 18. The main difference is in the design of the outer tube 120. The outer tube 120 comprises microchannels 124 arranged along the circular cross-section of the outer tube 120. Preferably, the washing liquid condenser inlet 82 is formed as a separate element whose outer surface is connected to the inner surface of the connection element 126 and to the inner surface of the outer tube 120.

The design of the washing liquid condenser outlet 84 and the refrigerant condenser inlet 86 are preferably designed as the washing liquid condenser inlet 82 and the refrigerant condenser outlet 88 described with respect to Figs. 18 and 19. Alternatively to the condenser configurations described according to Figs. 18 and 19, the washing liquid may flow in the outer tube 120 (or in the microchannels 124 forming the outer tube 120) of the condenser, and the refrigerant may flow in the inner tube 118 of the condenser.

The configuration of the washing liquid condenser inlet/outlet 82, 84 and/or the refrigerant condenser inlet/outlet 86, 88 may be applicable for any condenser disclosed herein.

Fig. 20 is a perspective view of the washing machine of Fig. 1 without the front and top wall and with another configuration of the top module and the compressor (compared to Fig. 4). Fig. 21 is a perspective view of the top module and the compressor of Fig. 20 with a partial section of the tray element, Fig. 22 is a bottom view of the top module and the compressor of Fig. 21, and Fig. 23 is a detailed perspective view of the switching valve of Fig. 21. Only the differences between the washing machine 2 according to Figs 20 to 23 and the washing machine 2 of Figs. 4 to 15 are outlined in the following. Otherwise, the elements and functions as described above with respect to the other elements correspondingly also apply individually, in subgroups or as a functional group to the embodiment of Figs. 20 to 24.

As shown in Fig. 20, the washing liquid supplied to the tub 58 of the washing machine 2 is circulated by and through the washing liquid circulation unit 64 to save water and energy. In the washing liquid circulation unit 64, the washing liquid is guided through the first, second, third and fourth water circulation sections 64A, 64B, 64c, 64d. The first water circulation section 64A connects the tub outlet (not shown, e.g. at the sump of the tub 58) to the circulation pump 66. The circulation pump 66 is preferably arranged in the bottom region, e.g. at the lower right comer at the front of the washing machine 2. The second water circulation section 64B extends between an outlet of the circulation pump 66 and the washing liquid condenser inlet 82 (see: Fig. 22), the third water circulation section 64c extends between the washing liquid condenser inlet 82 and outlet 84 (within the condenser inner tube 118, see: Fig. 18), and the fourth water circulation section 64d connects the washing liquid condenser outlet 84 to the tub 58 via the nozzle 65. As shown in Fig. 20, at least a portion of the second water circulation section 64B may extend along a side wall or a corner of the washing machine 2, e.g. at the left side of the washing machine 2 parallel to the side wall 10.

The circulation pump 66 is preferably arranged in the bottom region of the washing machine 2, e.g. in the lower left corner at the front of the washing machine 2. The circulation pump 66 is used to drain washing liquid (during a washing phase) or water (during a rinsing phase) from the sump of the tub 58, in particular from the drain manifold which is arranged at the lower part of the sump 140 and recirculate the liquid to the upper part of the tub 58 where the liquid is introduced into the tub 58 by the water inlet 65. The washing machine 2 in Fig. 20 further comprises the drain pump (not shown but compare 72 in Fig. 34). The drain pump, which is connected to a tub outlet (e.g. via the sump, in particular from the drain manifold which is arranged at the lower part of the sump 140) may be connected to the water drain (not shown, but compare 70 in Fig. 34) which is used for draining the washing liquid at the end of a washing cycle out of the washing machine 2. The drain pump is preferably arranged in the bottom region of the washing machine, e.g. in the lower right comer at the front of the washing machine 2 (corresponding to the drain pump 72 in Fig. 6).

The washing machine 2 may have a mixing pump 76 which may be connected to the tub outlet, and which drains water and detergent from the bottom of the tub (e.g. the sump of the tub 58, in particular from the drain manifold which is arranged at the lower part of the sump 140,) at the beginning of a washing cycle after detergent has been introduced into the tub 58 and re-send the water and detergent to the tub 58, e.g. to the sump of the tub or in particular to the tub 58 below a water heater (not shown), by a return line 77 (compare description of mixing pump 76 according to Fig. 6). The mixing pump 76 is preferably arranged in the bottom region of the washing machine, e.g. in the lower right corner at the front of the washing machine 2. Preferably, at least two of the drain pump 72, the circulation pump 66 and the mixing pump 76 are integrated in a pump group. Preferably a filter of the filter opening 68 is provided upstream of the mixing and drain circuit.

As shown in Fig. 21, the heat pump comprises the compressor 36, the evaporator 102 and the condenser 81 which are preferably arranged at the inside of the washing machine 2. The compressor 36 is preferably arranged in the bottom region, e.g. at the lower left comer at the front of the washing machine 2.

The refrigerant circulation circuit 42 comprises a first, second, third, fourth, fifth and sixth refrigerant circuit section. The first refrigerant circuit section 44B extends between the refrigerant condenser outlet 88 and the evaporator inlet 104, the second refrigerant circuit section 46B between the evaporator outlet 106 and the first inlet 78a of the switching valve 78 (refrigerant flow changing device), the third refrigerant circuit section 48B between the first outlet 79a of the switching valve 78 and the compressor inlet 110 (see Fig. 11), the fourth refrigerant circuit section 50B between the compressor outlet 112 and the second inlet 78b of the switching valve 78, the fifth refrigerant circuit section 52B between the second outlet 79b of the switching valve 78 and the refrigerant condenser inlet 86, and the sixth refrigerant circuit section 54a between the refrigerant condenser inlet 86 and outlet 88 which in this example are the inlet and outlet of an outer tube 120 of the condenser (see Fig. 18).

The first refrigerant circuit section 44B may be arranged at the underside of the evaporator tank 100 and may comprise the expansion device 40 for controlling the amount of refrigerant released into the evaporator 102 (see: Fig. 22). The third and fourth refrigerant circuit section 48B, 50B which preferably extend between the top and the bottom of the washing machine 2 are preferably flexible pipes. The piping of the remaining refrigerant circuit sections 44B, 46B, 52B (see: Fig. 23) - except the piping of the heat exchanger(s) itself, may also be provided as flexible pipes. The flexible pipes may be easily adapted to paths which are not straight without requiring mechanical bending. A large part of the third and fourth refrigerant circuit sections 48B, 50B may extend between the bottom region and the top region of the washing machine 2 where the top module 5a is arranged. The third and fourth circuit sections 48B, 50B may run along at the left side of the washing machine 2 from bottom to top parallel to the side wall 10 (see: Fig. 20). The switching valve 78 may be arranged below the evaporator tank 100, preferably below the evaporator tank 100 at the right front comer of the washing machine 2, in particular between the tank 100 and the tub 58. The valve 78 may be arranged in a horizontal, but preferably vertical position.

The top module 5a shown in Figs. 21 to 23 is similar to the top module 5a shown in Fig. 4, in particular the outer shape of the tray elements and the arrangement and shape of the condenser 81 are equal. In the following the differences are outlined. As the compressor 36 of Fig. 21 is arranged at the bottom of the washing machine 2, the tray element 6a does not comprise any opening for receiving the compressor (cf. top module 5a of Fig. 4). The tray element 6a comprises an evaporator tank 100, wherein the tank 100 may extend over the entire or substantial horizontal surface area of the tray element 6a. When seen in top view, the evaporator tank 100 preferably extends over the whole horizontal area of the tray element 6a which is surrounded by the condenser 81. The evaporator tank cover 32 preferably has a shape identical or substantially identical to the shape of the tank 100 when seen in top view for covering the whole evaporator tank 100. The evaporator tank 100 has a flat shape and thus a horizontal bottom surface compared to the tank 100 of Fig. 4. As shown in Fig. 21, the evaporator 102 positioned within the tank 100 may be arranged at a single horizontal level. Alternatively, the evaporator 102 may extend in several, e.g. two or three vertically different levels. The evaporator 102 preferably has a meander shape.

Fig. 24 is a perspective view of the washing machine of Fig. 20 with a microchannel arrangement. The only difference between the tray elements 6a of Figs. 21 to 23 and Fig. 24 is that as an evaporator a microchannel arrangement 116 (components already described in connection with Fig. 16) is used instead of an evaporator 102 formed by pipes. The microchannel arrangement 116 is preferably arranged horizontally within the evaporator tank 100. Preferably, when seen in top view, the microchannel arrangement 116 is arranged within the tank 100 such that the microchannel elements 116a are parallel to the front and rear wall of the washing machine 2.

Fig. 25 is a perspective view of the washing machine of Fig. 20 with another configuration of the top module. Fig. 26 is a top view of the top module of Fig. 25 with an intersection line A-A, Fig. 28 is an exploded view of the top module of Fig. 25, and Fig. 29 is a perspective view from below of the top module and the compressor of Fig. 25. The inner and outer structure of the washing machine of Fig. 25 is identical to the washing machine of Fig. 20. Therefore, only the differences between both washing machines 2 are outlined in the following. Otherwise, the elements and functions as described above with respect to the other elements of the washing machine of Fig. 20 correspondingly also apply individually, in subgroups or as a functional group to the embodiment of Fig. 25.

As shown in Fig. 25, the washing liquid supplied to the tub 58 of the washing machine 2 is circulated by and through the washing liquid circulation unit 64 to save water and energy. In the washing liquid circulation unit 64, the washing liquid is guided through the first, second, third and fourth water circulation sections 64A, 64B, 64c, 64d. Further details regarding the washing liquid circulation and also the pumps have already been described above according to Figs. 20 to 23.

The washing machine of Fig. 25 differs from the washing machine of Fig. 20 in the configuration of the top module 5b and in the routing of the refrigerant circuit sections between the compressor 36 and the switching valve 78.

As shown in Figs. 25, 27 and 28, the top module 5b may comprise a tray element 6b which may have the same external shape as the tray element 6a of Fig. 20, but may have a different inner structure. The tray element 6b comprises the evaporator tank 100 which may be arranged on only one side of the entire tray element 6b. Preferably, the tank 100 is arranged on the right side of the tray element 6b when seen the washing machine in front view. The switching valve 78 may be arranged between the top module 5b and the drawer housing 12a. Preferably, the switching valve 78 and/or at least portions of the refrigerant circuit sections may be arranged in the remaining portion of the tray element 6b, next to the evaporator tank 100. Preferably, the switching valve 78 is arranged horizontally, more preferably the longitudinal axis of valve 78 is parallel to the front/rear wall of the washing machine 2. The tray element 6b may further comprise a maintenance opening 128, preferably with a rectangular shape, arranged above the switching valve and/or the refrigerant circuit sections.

In particular, as shown in Figs. 25, 26, 29 and 30, the refrigerant circulation circuit 42 comprises a first, second, third, fourth, fifth and sixth refrigerant circuit section. The first refrigerant circuit section 44C extends between the refrigerant condenser outlet 88 and the evaporator inlet 104, the second refrigerant circuit section 46C between the evaporator outlet 106 and the first inlet 78a of the switching valve 78 (refrigerant flow changing device), the third refrigerant circuit section 48C between the first outlet 79a of the switching valve 78 and the compressor inlet 110 (see Fig. 11), the fourth refrigerant circuit section 50C between the compressor outlet 112 and the second inlet 78b of the switching valve 78, the fifth refrigerant circuit section 52C between the second outlet 79b of the switching valve 78 and the refrigerant condenser inlet 86, and the sixth refrigerant circuit section 54a (see: Fig. 27) between the refrigerant condenser inlet 86 and outlet 88 which in this example are the inlet and outlet of an outer tube 120 of the condenser (see Fig. 18).

As shown in Fig. 29, the evaporator inlet and/or outlet 110 may be arranged on a side wall of the evaporator tank 100, preferably on the left side wall when looking to the washing machine in front view. Alternatively, the evaporator inlet and/or outlet 110 may be arranged at the bottom of the evaporator tank 100.

Fig. 27 is a sectional view of the top module according to the intersection line A- A of Fig. 26. The evaporator tank 100 of the tray element 6b may comprise the upper region 100a arranged above the lower region 100b as already described in relation to Figs. 15 and 17A-C. The side walls of the evaporator tank 100 enclosing the upper region 100a of Fig, 27 may be connected to the side wall of the evaporator tank 100 enclosing lower region 100b by a rounded surface, but also any other form is applicable, e.g. the forms described in connection with Figs. 15 and 17A-C. The upper region and the lower region may accommodate a portion of the evaporator 102, respectively. The evaporator 102 may be arranged in an inclined plane wherein the pipes of the evaporator 102 in the lower region are lower than the pipes in the upper region (cf. Fig. 17A). Preferably, the evaporator 102 is mounted on a mounting element 108 that fixes and defines the inclined position of the evaporator within the tank 100.

Fig. 30 is another perspective view from above of the top module and compressor of Fig. 29 with partial section of the tray element. Preferably, the refrigerant entering the evaporator 102 is guided to the portion of the evaporator 102 in the lower region of the tank 100 (cf. Fig. 27) and exits the tank through the portion of the evaporator 102 in the upper region of the tank 100. Therefore, ice forms in the lower region of the tank and pushes upwards where the tank preferably has a gaseous volume 114 for ice expansion (see: Fig. 27).

Fig. 31 is a perspective view of the washing machine of Fig. 25 with a microchannel arrangement. The only difference between the tray elements 6b of Fig. 31 and Figs. 25 to 30 is that as an evaporator the microchannel arrangement 116 (components already described according to Fig. 16) is used instead of an evaporator 102 formed by pipes. The microchannel arrangement 116 is preferably arranged obliquely within the evaporator tank 100 such that a first portion is positioned in the upper region and another portion is positioned in the lower region (cf. evaporator 102 of Fig. 27).

Fig. 32 is a perspective view of the outer appearance of another washing machine with a top module. The outer appearance is similar to the washing machine 2 of Fig. 1. The front wall 8 may comprise a cover for a service opening 22a. The cover for service opening 22a is preferably arranged on the right side of the lower region. In this case, the top may be formed by a top module 5c which may be mounted on the cabinet 4 by fastener elements, e.g. by screws or snap-in elements. A top wall 9a (e.g. work top) may be arranged on top of the washing machine 2, in particular on top of the top module 5c.

Fig. 33 is an exploded view of the washing machine of Fig. 32 without the front and top wall. Fig. 34 is a detailed perspective view of the pump arrangement of Fig. 32 and Fig. 35 is a front view of the upper portion of the washing machine of Fig. 32 without the front wall. The inner structure below the top module 5c of the washing machine 2 of Fig. 33 may be identical to the inner structure of the washing machine 2 according to Figs. 25 to 31. Therefore, only the differences between both washing machines 2 are outlined in the following. Otherwise, the elements and functions as described above with respect to the other elements of the washing machine of Figs. 25 to 31 correspondingly also apply individually, in subgroups or as a functional group to the embodiment of Figs. 32 to 41.

The tray element 6c of the top module 5c is similar to the tray element 6c of the washing machine of Fig. 25. The maintenance opening 128 may have a different shape than a rectangular shape, or preferably has a rectangular shape with round edges when seen in top view. The maintenance opening 128 is only optional. The evaporator tank 100 may have a rectangular outer contour when seen in top view.

The washing liquid supplied to the tub 58 of the washing machine 2 is circulated by and through the washing liquid circulation unit 64 to save water and energy. In the washing liquid circulation unit 64, the washing liquid is guided through the first and the second water circulation section 64A, 64B and through a third and fourth water circulation section 64c*, 64d*. Further details regarding the washing liquid circulation unit 64 and also the pumps have already been described above according to Figs. 20 to 23.

The third and fourth water circulation sections 64c*, 64d* connect the same components as sections 64c, 64d of Fig. 25, but have a different length. In particular, the condenser 81 of Fig. 33 is extended compared to the condenser of Fig. 25. The extension improves the heat exchange efficiency, in particular the washing liquid is warmed faster. Preferably, the condenser 81 extends along three or four sides of the tray element 6c. The condenser 81 may further extend within the tray element 6c next to the evaporator tank 100. Preferably, the condenser 81 comprises 1,4, 1,6 or 1,8 windings.

Fig. 36 is an exploded view of the top module and the compressor of Fig. 33 and Fig. 37 is an exploded view of the top module and the compressor of Fig. 33 in another perspective view. The refrigerant circulation circuit 42 comprises a first, second, third, fourth, fifth and sixth refrigerant circuit section. The first refrigerant circuit section 44D extends between the refrigerant condenser outlet 88 and the evaporator inlet 104, the second refrigerant circuit section 46D between the evaporator outlet 106 and the first inlet 78a of the switching valve 78 (refrigerant flow changing device), the third refrigerant circuit section 48D between the first outlet 79a of the switching valve 78 and the compressor inlet 110 (see Fig. 11), the fourth refrigerant circuit section 50D between the compressor outlet 112 and the second inlet 78b of the switching valve 78, the fifth refrigerant circuit section 52D between the second outlet 79b of the switching valve 78 and the refrigerant condenser inlet 86, and the sixth refrigerant circuit section 54b (see: Fig. 40) between the refrigerant condenser inlet 86 and outlet 88 which in this example are the inlet and outlet of an outer tube 120 of the condenser (see Fig. 18). The first refrigerant circuit section 44D may comprise an expansion device 40 (e.g. a capillary as shown in Fig. 36) for controlling the amount of refrigerant released into the evaporator 102.

The switching valve 78 may be arranged below the condenser 81, preferably between drawer housing 12a and rear wall 24 of the washing machine 2. Most preferably, the longitudinal axis of the switching valve 78 extends vertically (in an operational position of the washing machine (see Fig. 33).

As shown in Fig. 29, the evaporator inlet and/or outlet 110 may be arranged on a side wall of the evaporator tank 100, preferably on the rear side wall when seen the washing machine in front view. Most preferably above the evaporator 102. Alternatively, the evaporator inlet and/or outlet 110 may be arranged at the bottom of the evaporator tank 100.

As shown in Fig. 36, the evaporator tank 100 may comprise mounting elements 108 and/or the side facing the evaporator tank 100 of the evaporator tank cover 32 may comprise fixing elements 138, each for fixing the evaporator 102 when arranged within the tank 100.

Fig. 38 shows a perspective view of the top module and the evaporator of Fig. 33 with partial section of the tray element. The tray element 6b may comprise a recess provided on an underside of the tray element 6c (a surface of the tray element 6c facing the tub 58 of the washing machine when mounted) that may form a channel extending along at least one side of the evaporator tank 100. The channel preferably has the shape of the condenser 81, for receiving the condenser 81 when mounted on top of the washing machine 2. The condenser 81 is guided at least partially around the evaporator 102, preferably extending along one side, two sides, three sides or four sides of the evaporator tank 100.

Fig. 39 is a top view of the top module of Fig. 33 with an intersection line A- A, Fig. 40 is a sectional view of the top module according to the intersection line A-A of Fig. 39, and Fig. 41 is a perspective view of the evaporator of Fig. 40.

As shown in Fig. 40, the cross-sectional shape of the evaporator tank 100 is equal to the shape of the tank 100 as already described with respect to Fig. 27. The volume of the upper region 100a and the lower region 100b are indicated by dotted lines, respectively. The configuration of the evaporator 102 of Fig. 40 differs from the evaporator of Fig. 27.

When seen the pipes of the evaporator in cross-section as shown in Fig 40, the pipes of the evaporator 102 may be arranged in meandering form within the tank. In particular, when seen the vertical cross-section of Fig. 40, the windings of the meandering form are arranged in curved surfaces arranged at vertically different levels, wherein the curved surfaces are preferably adapted to the curved surface of the bottom of the tank 100. Preferably, the refrigerant entering the evaporator tank 102 is first guided to the portion of the evaporator 102 arranged in the lower region 100b of the tank 100 and exits the tank 100 through the portion arranged in the upper region 100a. The refrigerant may first be guided through the pipes closest to the bottom surface of the tank and then through the pipes arranged above.

Such an arrangement allows an even distribution of the evaporator pipes within the tank 100 and the best possible use of the tank space. Thus, the length of the evaporator 102 and in particular the heat exchanging surface can be increased. This results in a washing machine with a higher heat exchanging efficiency.

Fig. 41 A is an exploded view of the tray element 6c, the evaporator tank 100 and the evaporator tank cover 32 of Fig. 40. As shown in Fig. 41A the evaporator tank 100 and/or the evaporator tank cover 32 may be formed as a separate piece to be connected detachably or non-detachably to the top module, in particular to the tray element 6c, e.g. by screwing or by welding (i.e. the tank 100 and/or the tank cover 32 may become integral with the top e.g. before or after the tank has been filled with liquid/water). E.g. the evaporator tank cover 32 is mounted on top of the tank 100 and the whole tank is then mounted from below or from above to the tray element 6c. As shown in Fig. 41 A, the tank 100 and the cover 32 are formed as separate elements which are mounted from above to the tray element 6c. The top module 6c may comprise an opening 107 for receiving the evaporator tank 100. Preferably, a gasket is provided between the cover 32 and the evaporator tank 100. Preferably, one of the evaporator tank 100 and the evaporator tank cover 32 is formed in a single piece (integrally) with the top module, in particular with the tray element 6c, wherein the other element is connected to the tray element 6c e.g. by screwing, or preferably becoming integral with the tray element 6c e.g. before or after the tank 100 has been filled with water. In particular, in case the tank 100 is formed in a single piece with the tray element 6c, the evaporator tank cover 32 is a separate element which is mounted detachably or non-detachably, in particular from above, to the tray element 6c. Otherwise, the cover of the tank 32 may be formed in a single piece with the tray element 6c and the evaporator tank 100 may be mounted as a separate part, in particular from below, to the cover 32 formed in the tray element 6c. The tank assembly formed by the tank 100 and the cover 32 (wherein one of them may be formed in a single piece with the tray element 6c) may be insulated with a heat insulating coverage, in particular with a heat insulating coverage mounted at the external surface of the tank 100. The configurations of the tray element 6c, the evaporator tank 100 and the evaporator tank cover 32 described in this paragraph may be applicable to all embodiments of washing machines/washer dryer described above and further below.

Fig. 4 IB is a perspective view of the evaporator of Fig. 40 with mounting elements for the evaporator 102 and Fig. 41C is an exploded view of the evaporator of Fig. 4 IB. One mounting element 108a may be mounted on each side of the evaporator 102. The mounting elements 108a may be adapted to keep the pipes of the evaporator 102 at a distance from each other and in particular to keep the evaporator in its position when mounted inside the evaporator tank 100 - as shown in Fig. 40. Each mounting element 108a may comprise openings for receiving pipes of the evaporator 102. As shown in Fig. 4 IB, each mounting element 108a may comprise one opening for each portion of the evaporator in which the evaporator pipes form a reversal of direction. One of the mounting elements 108a may be pushed onto the evaporator 102 from each side with its openings. The evaporator 102 with the mounting elements 108a mounted at the evaporator 102 may be mountable within the evaporator tank 100 by e.g. a plug-in connection, a screw connection or suchlike. The connection may be designed to be detachable or non-detachable. The mounting elements 108a may prevent the evaporator pipes from moving away from their position due to the forces exerted by the ice on the evaporator 102 when ice forms in the evaporator tank 100. Such mounting elements 108a may be used with any of the above evaporators arranged in the tank 100 described herein.

Fig. 41D is a perspective view of the evaporator with another shape and Fig. 41E is a perspective view of the evaporator of Fig. 4 ID in an assembled state within the tray element 6c shown in Fig. 40. As shown in Fig. 4 ID, the evaporator 102 may comprise an upper planar plane and a lower planar plane each formed by pipes of the evaporator, wherein the upper and lower planes are inclined to each other. When looking perpendicular (vertically) at the upper and/or lower plane, the pipes of the evaporator 102 in the respective planes may form a spiral. Preferably, the pipes of the upper and lower plane are connected to each other at a central position of the evaporator, preferably at the middle of the spiral shape. Alternatively, the pipes within each plane may form a meandering shape. As shown in Fig. 4 IE, the upper plane of the evaporator 102 may be arranged horizontally when mounted within the evaporator tank 100, wherein the lower plane is inclined with respect to the upper plane when seen the tank 100 from a front view. The inclination of the lower plane may be adapted to the shape of the evaporator tank 100, in particular to the shape of the side wall of the evaporator tank 100.

As already described with respect to the evaporator 102 shown in Fig. 4 IB, the refrigerant entering the evaporator tank 100 is preferably introduced through inlet 104 into the lower plane of the evaporator, then flows from the lower plane to the upper plane of the evaporator and exits the tank through the outlet 106. Therefore, it is ensured that ice is formed from bottom to top within the evaporator tank 100. By the shape of the evaporator 102 with the lower and upper plane, the volume of the evaporator tank 100 can be covered effectively. Therefore, an efficient heat transfer between the medium stored within the evaporator tank 100 and the refrigerant flowing through the evaporator pipes arranged within the tank 100 is ensured.

Fig. 42 is a perspective view of the washing machine of Fig. 32 without the front and top wall and with another configuration of the circulation pump. Fig. 43 is a detailed perspective view of the pump arrangement of Fig. 42 and Fig. 44 is a front view of the washing machine of Fig. 42. The basic design of the washing machine of Figs. 42 to 44 may be identical to the washing machine of Fig. 33. Therefore, only the differences between both washing machines 2 are outlined in the following. Otherwise, the elements and functions as described above with respect to the other elements of the washing machine of Fig. 33 correspondingly also apply individually, in subgroups or as a functional group to the embodiment of Figs. 42 to 44.

The circulation pump (jet pump) 66 may be arranged below the tub 58, in particular the circulation pump 66 is fixed to the tub 58 from below (difference to the circulation pump of Fig. 33 which is arranged at the bottom right comer of the washing machine). A first water circulation section 64A* connects the tub outlet to the circulation pump 66. In particular, a first portion of the first water circulation section 64A* is connected to the filter opening 68 and a second portion of the first water circulation section 64A* connects the filter opening 68 with the circulation pump 66 (see: Fig. 43). As shown in Fig. 44, a second water circulation section 64B* connects the circulation pump outlet with the washing liquid condenser inlet (not shown, cf. Fig. 33).

Fig. 45 is a perspective view of the washing machine of Fig. 42 without the side walls and the rear wall and with an evaporator tank water regeneration arrangement. Fig. 46 is a detailed perspective view of the pump arrangement of Fig. 45 and Fig. 47 is an exploded view of the compressor, the pump arrangement and the top module of Fig. 45. The basic design of the washing machine of Figs. 45 to 50 may be identical to the washing machine of Figs. 42 to 44. Therefore, only the differences between both washing machines 2 are outlined in the following. Otherwise, the elements and functions as described above with respect to the other elements of the washing machine of Figs. 42 to 44 correspondingly also apply individually, in subgroups or as a functional group to the embodiment of Figs. 45 to 50.

As shown in Figs. 45, 46 and 47, the mixing pump 76 (chamber circulation pump) is the same mixing pump as described with respect to the other Figures, but the mixing pump may have another function. In particular, the mixing pump 76 may be used for sucking washing liquid from the tub 58 and conveying the washing liquid through the evaporator tank 100 (instead of using the mixing pump 76 for draining washing liquid from the tub and re-introducing the washing liquid via return line 77 into the tub 58 as shown e.g. in Figs. 42 to 44 and 46A to 46C).. Alternatively, instead of changing the function of the mixing pump 76, a further chamber circulation pump may be provided for sucking liquid from the tub 58 and conveying the washing liquid through the evaporator tank 100 in addition to the mixing pump 76 for draining washing liquid from the tub 58 and re-introducing the washing liquid into the tub 58. The water exiting the evaporator tank 100 may be guided directly into the tub 58 or sump fluidly connected to the tub 58 or another fluid line fluidly connected to the tub 58 (e.g. detergent housing). Alternatively, the washing liquid is drained by the drain pump (not shown). Preferably, a filter 68 is provided downstream of the tub 58, most preferably in the passage from the tub to the drain pump 72 (shown in Fig. 47). The circulation of liquid from the tub through the evaporator tank serves for (accelerating the) melting the frozen liquid in the tank. Thereby in the next washing and/or drying cycle the liquid stored in the heat exchanging medium stored in the evaporator tank (here the liquid previously recirculated) has a higher internal heat that may be reused in the next cycle.

The mixing pump 76 may be arranged in a bottom region of the washing machine 2, preferably in the lower right comer at the front of the washing machine 2. The washing machine 2 may also comprise a drain pump (not shown) for draining the washing liquid by the water drain 70. Preferably, the drain pump (not shown) and the mixing pump 76 are integrated in a pump group (see: Fig. 46). The drain pump 72 and the mixing pump 76 may be operated simultaneously or intermittently. In particular, the mixing pump 76 may suck warm water from the tub 58 and conveys the warm water through the evaporator tank 100. While conveying the water through the evaporator tank 100, the warm water cools by exchanging heat with the evaporator 102 in the evaporator tank 100 (i.e. melting of ice formed in the evaporator tank 100). The washing liquid sucked from the tub 58 forms the heat exchanging medium. The drain pump 70 may drain the cold water coming back from the evaporator tank 100 and the mixing pump (chamber circulation pump) 76 may suck new warm water from the tub of the washing machine. Thus, the water circulating through the evaporator tank 100 is preferably not always the same but it is renewed with hot water sucked by the mixing pump from the tub. The mixing pump 76 may comprise a first water regeneration line 132a which guides the circulated liquid from the mixing pump 76 to the evaporator tank 100 in the tray element 6c of the top module 5c through inlet 135a of pipe 134a. A second water regeneration line 132b may guide the circulated liquid in the evaporator tank 100 from an outlet 135b at pipe 134b to the filter 68 at the bottom of the machine. From the filter 68, the water may be drained at least partially by the drain pump 70, wherein in particular new warm water from the tub may be sucked such that the liquid exiting the evaporator tank 100 is mixed at the filter 68 with fresh warm water from the tub. Alternatively, line 132b is fluidly connected to the inside of the tub to return the liquid from the evaporator tank 100 into the tub and from there to the inlet of mixing pump 76. In particular, the first water regeneration line 132a connects the mixing pump 76 with an evaporator tank inlet (or outlet) 130a and the second water regeneration line 132b connects the mixing pump 76 with an evaporator tank outlet (or inlet) 130b.

As shown in Fig. 45, at least a portion of the first and/or second water regeneration line 132a, 132b may extend along a side wall or a corner of the washing machine 2, e.g. at the right side of the washing machine 2 parallel to the side wall 10 (not shown). The evaporator tank inlet and/or outlet 130a, 130b may be arranged at the bottom of the evaporator tank 100, preferably at the in the lower right comer at the front of the evaporator tank 100.

In the following Figs. 46A-C are described. Here only the differences between the washing machine according to Figs. 46A-C and the washing machine 2 of Fig. 45 are outlined in the following. Otherwise, the elements and functions as described above with respect to the other elements correspondingly also apply individually, in subgroups or as a functional group to the embodiments of Fig. 46A-C.

Fig. 46 A is a perspective view of the compressor, the pump arrangement and the top module of the washing machine of Fig. 45 and 47 to 50 without the evaporator tank water regeneration arrangement and another arrangement of the jet pump. The main difference between the washing machine 2 of Fig. 45 and the arrangement shown in Fig. 46A is the position of the jet pump. As shown in Fig. 46A, the jet pump 66 is arranged at the bottom of the washing machine (difference to the jet pump of Fig. 45 which is fixed to the tub from below), in particular at the front of the bottom of the washing machine. Preferably, the jet pump 66 is arranged in a central or substantially central position, in particular at the front of the bottom of the washing machine. Due to the new position of the pump, the water circulation section 64A* between the tub and the jet pump 66 and the water circulation section 64B* between the jet pump 66 and the condenser inlet (not shown) may be guided differently. Section 64A* between the filter 68 and the tub preferably runs parallel or substantially parallel to the bottom of the washing machine. Section 64B* is preferably guided above the compressor 36 and then vertically or substantially vertically and parallel along the side wall (e.g. at the corner between the front and the side wall) in the direction of the tray element 6c. This arrangement has the advantage that the jet pump 66 is separate from the other pumps, in particular the drain pump 72 and mixing pump 76. Thus, the replacement or service of the pumps may be simplified. Fig. 46B is a perspective view of the washing machine of Fig. 45 without the evaporator tank water regeneration arrangement and with another configuration of the jet pump 66 and the condenser 81b. The main difference between the washing machine 2 of Fig. 45 and the arrangement shown in Fig. 46B is the position of the jet pump 66 and the shape of the condenser 81b. As shown in Fig. 46B, the jet pump 66 is arranged at a rear position, preferably at the rear left comer of the washing machine (difference to the jet pump of Fig. 45 which is fixed to the tub from below). Due to the new position of the pump, the water circulation section 64A* between the tub and the jet pump 66 and the water circulation section 64B* between the jet pump 66 and the condenser inlet (not shown) may be guided differently. Section 64a* between the filter 68 and the tub is preferably guided from the front to the back of the washing machine. Preferably, section 64a* is guided from the right front corner to the left rear comer of the bottom of the washing machine (i.e. shortest distance). Section 64b* is preferably guided from the outlet of the jet pump 66 vertically or substantially vertically (preferably vertically and parallel to the side walls of the washing machine) in the direction of the condenser inlet 82.

As shown in Fig. 46B, the condenser inlet 82 is arranged at the rear of the top when seen the washing machine from front view. Preferably, starting from the condenser inlet 82, the condenser 81b forms a clockwise spiral along the edges of the tray element 6d. The condenser outlet 84 may be arranged parallel to the side walls of the washing machine, preferably the condenser outlet 84 is arranged on the right side of the drawer housing 12a, when seen the washing machine from a front view.

By arranging the jet pump at the rear side, the inner volume of the washing machine may be used more efficient as at the front now more space is available (space at the rear of the bottom of the washing machine is otherwise unused). This may open up new possibilities for the arrangement of components at the front and/or service may be carried out more easily due to the increased space at the front. Further, this positioning of the jet pump 66 and the condenser inlet 82 may result in shorter water circulation sections 64a*, 64b*.

Fig. 46C is a perspective view of the washing machine of Fig. 46B with another arrangement of the condenser 81c and the switching valve 78. As shown in Fig. 46C, the condenser inlet 82 is arranged at the left side of the top of the washing machine when seen in front view. In particular, the inlet 82 is arranged at the rear, in particular, at the rear left comer of the top of the washing machine. Preferably, starting from the condenser inlet 82, the condenser 81c forms a counterclockwise spiral along the edges of the tray element 6c. The condenser outlet 84 may be arranged parallel to the side walls of the washing machine, preferably the condenser outlet 84 is arranged on the right side of the drawer housing 12a, when seen the washing machine from a front view. The switching valve 78 may be arranged horizontally between the condenser inlet and outlet 82, 84, preferably parallel to the condenser inlet and outlet 82, 84. This arrangement of the condenser 81c may create more space in the region between the condenser inlet and outlet 82, 84 and thus more space for the switching valve 78. Thus, more space for mounting and service of the switching valve 78 is available.

Fig. 48 shows a perspective view of the top module of Fig. 45 without the evaporator tank cover 32. The evaporator tank 100 may comprise a pipe 134a, 134b for each evaporator tank inlet and outlet 130a, 130b (see: Fig. 47), preferably extending from the evaporator tank inlet and outlet 130a, 130b vertically upwards. The pipes 134a, 134b and the evaporator tank inlet and outlet 130a, 130b may be arranged between the side wall of the evaporator 100 and the evaporator 102, preferably at least partially in the side wall of the evaporator 100. In the example as shown pipe 134a is the inlet pipe coming from (connected to) the mixing pump 76 and the outlet 135b at pipe 134b acts as an overflow keeping the liquid in the evaporator tank at a maximum liquid level. The vertical distance between the space maximum liquid level defined by the overflow at pipe outlet 134b and the upper wall of the evaporator tank (provided by the inner side of cover 32) may provide the gas volume for the expansion of the ice during the freezing of the liquid in the tank.

Fig. 49 is a perspective view from below of the evaporator tank cover of Fig. 45 and Fig. 50 shows a perspective view of the top module of Fig. 48 with the fixing elements and the separation wall of the bottom of the evaporator tank cover when mounted. The evaporator tank cover 32 may comprise a separation element 136 on the side facing the evaporator tank 100. The separation element 136 is configured for guiding the washing liquid supplied from the tub 58 (see: Fig. 45) into the evaporator tank 100 by the mixing pump 76 along a path within the tank 100 when the evaporator tank cover 32 is mounted on the evaporator tank 100. The separation element 136 may be configured such that the washing liquid passes over the entire or substantially entire ice formed around the evaporator pipes. When the ice is melting, the washing liquid may reach/pass through all pipes of the evaporator 102. The evaporator tank cover 32 may further comprise fixing elements 138 for fixing the pipes of the evaporator 102 when the cover 32 is mounted on the top of the tank 100. The separation element 136 improves the replacement of liquid already stored in the evaporator tank by (fresh) liquid supplied by the operation of the mixing pump 76. In case of frozen or partially frozen liquid in the tank 100 the separation element 136 improves the spreading of the circulated liquid at least over the upper surface of the frozen liquid such that melting is improved due to wider distribution of the warmer circulated liquid. Thus the effect of the overflow is not only to create and maintain the gas volume above the liquid in the tank, but additionally to provide space above the (possibly) frozen liquid such that circulation of the liquid can be effected at all and is not prevented by blocking passages with the expanded ice. Correspondingly the gas volume is larger for the evaporator tank where the liquid can be exchanged as compared to the gas volume in tanks where the liquid (heat exchanging medium) is not exchanged.

Fig. 51A is a perspective view of the washing machine of Fig. 46C in an assembled state without the front wall, rear wall and side walls and with an evaporator tank water regeneration arrangement. Only the differences between the washing machine of Figs. 51A and 46C are outlined in the following. Otherwise, the elements and functions as described above with respect to the other elements of Fig. 46C correspondingly also apply individually, in subgroups or as a functional group to the embodiment of Fig. 51 A.

Instead of draining washing liquid from the tub and reintroducing the washing liquid into the tub by the mixing pump 76 to achieve a better mixing between the washing water and the washing liquid (i.e. detergent) as it is shown in Fig. 46C, in the washing machine of Fig. 51 A, the washing liquid is sucked from the tub 58 and is pumped through the evaporator tank 100 as it has already been described with respect to e.g. Figs. 45 and 47. I.e. the washing machine shown in Fig. 51A is equipped with the water regeneration arrangement shown in Fig. 45.

The first water regeneration line 132a may guide the circulated washing liquid from the mixing pump 76 to the evaporator tank 100 in the tray element 6c of the top module via inlet 135a of pipe 134a (not shown). The second water regeneration line 132b may guide the circulated washing liquid in the evaporator tank 100 from the outlet 135b at pipe 134b (not shown) to the filter 68 at the bottom of the machine. From the filter 68, the water may be drained at least partially by the drain pump 70, wherein in particular new warm water from the tub may be sucked such that the liquid exiting the evaporator tank 100 is mixed at the filter 68 with fresh warm water from the tub. Alternatively, the second water regeneration line 132b is fluidly connected to the inside of the tub 58 to return the liquid from the evaporator tank 100 into the tub 58 and from there to the inlet of mixing pump 76. The first water regeneration line 132a may connect the mixing pump 76 with an evaporator tank inlet (or outlet) 130a, in particular with the inlet pipe 134a, and the second water regeneration line 132b may connect the mixing pump 76 with an evaporator tank outlet (or inlet) 130b, in particular with the outlet pipe 134b.

Fig. 5 IB is a perspective view of the washing machine of Fig. 51 A with another configuration of the evaporator tank water regeneration arrangement. The first water regeneration line 132a and the second water regeneration line 132b are connected to the evaporator tank 100 in reverse (i.e. when seen from a front view, line 132b at the front of the tank forms the outlet and line 132a at the rear of the tank forms the inlet). In comparison, this is the other way round in the washing machine in Fig. 51 A. Therefore, in Fig. 5 IB, the washing liquid entering the tank 100 flows through the tank 100 in reverse. This reversal may be applicable to all embodiments described herein to exchange the connections of the lines 132a and 132b at the tank 100 so that the direction of flow of the washing liquid through the tank 100 is reversed.

The second water regeneration line 132b forming the outlet of the tank 100 in Fig. 5 IB may be connected to the tub 58 (not to the filter 68 as it is shown in Fig. 51 A), preferably to a nozzle 63 arranged at the bellow 62 (i.e. the bellow connecting the tub 58 to the cabinet). Preferably, the nozzle 63 is arranged at an upper region of the bellow 62 when seen from a front view (e.g. region above the rotation axis of the drum or the region above the middle level of the cabinet). In this case, the washing liquid exiting the evaporator tank 100 may be circulated through the tub 58 via the nozzle 63 arranged at the bellow 62. The washing liquid exiting the tub 58 may then be drained by the drain pump (not shown) or may be circulated again through the evaporator tank 100 by the mixing pump 76.

By guiding the washing liquid into the tub 58 through the bellow 62, it is ensured that the line 132b empties itself due to the force of gravity. This reduces the risk of clogging of the line 132b due to dirt (e.g. due to fluff or deposits of the washing liquid) and/or of becoming blocked due to freezing of washing liquid remaining in the line 132b. Thus, a permanent circulation of the washing liquid through the evaporator tank 100 can be ensured.

In the following Figs. 53 to 55F, the washing liquid is circulated through the evaporator tank 100 in the same flow direction as described in Fig. 5 IB and thus in reverse to the flow direction shown in Fig. 51 A. However, the function of the pipe sections 134a, 134b and thus the flow direction may be exchanged in any of the embodiments described herein by exchanging at the evaporator tank 100 the connected first and second water regeneration lines 132a, 132b with each other.

Fig. 52 is an exploded view of the tray element 6c of Figs. 51A and 5 IB. The evaporator tank 100 may comprise an insulation layer 38 enclosing the evaporator tank 100 in the assembled state. The insulation layer 38 may comprise a recess for each pipe of the evaporator 102 (i.e. the pipe introducing refrigerant into the evaporator tank 100 and the pipe guiding refrigerant out of the tank 100) and/or may comprise at least one recess for pipes 134a, 134b for circulating the washing liquid through the tank 100. The shape of the insulation layer 38 is preferably adapted to the shape of the evaporator tank 100. Thus, space within the washing machine can be saved. The evaporator tank cover 32 may comprise an insulation layer 31 which is mountable at the top of the cover 32 as it is shown in Fig. 52. Alternatively, the insulation layer 31 may be mounted at the bottom side of the cover 32.

The evaporator tank may be mounted from below to the tray element 6c. The tank cover 32 may form the top of the evaporator tank 100 when it is assembled. The insulation layer 38 of the tank may be mounted from below at the tray element 6c, in particular to the evaporator tank 100 from below e.g. by screwing or gluing, such that it encapsulates the evaporator tank 100. The tank 100, the layer 38, the tray element 6c and the cover 32 may comprise holes that are coaxial to each other, so that for mounting one screw may be inserted through all of these components (i.e. forming e.g. a screw-nut connection). Alternatively, the cover 32, the tank 100 and the insulation layer 38 are mounted to the tray element 6c by e.g. screwing, gluing or welding. Further configurations for the design and connection between the tray element, the tank 100 and the cover 32 have already been described with respect to Fig. 41 A.

Fig. 53 is a sectional view of the pipe section for guiding water within the evaporator tank of Fig. 52. Each of the pipe sections 134a, 134b may be arranged at the bottom of the tank 100, preferably extending from the outside to the inside of the tank 100 through the bottom wall of the tank 100. As shown in Fig. 53, pipe sections 134a, 134b are formed identically regarding their shape and their length. Alternatively, one of the pipe sections 134a, 134b may have a different upper and/or lower level. The pipe sections 134a, 134b may be arranged vertically or substantially vertically, but may also be arranged inclined with respect to a horizontal surface, i.e. bottom of the tank 100. As shown in Fig. 53, the pipe sections 134a, 134b are arranged adjacent to each other, in particular at the front right corner when seen the tray element 6c from a front view (compare Fig. 51 A). Alternatively, the pipe sections 134a, 134b may also be arranged apart from each other, e.g. the inlet pipe 134a at the front right corner and the outlet pipe 134b at the rear right corner.

As shown in Fig. 53, pipe sections 134a, 134b, in particular the inlet 135a and the outlet 135b, have the same upper level, in particular the upper levels are above the evaporator 102, wherein a gaseous volume (e.g. air) is maintained above the pipes 134a, 134b, in particular between the upper levels of the pipes 134a, 134b and the lower level of the evaporator tank cover 32. The upper level of the pipe sections 134a, 134b may be configured such that when the maximum level of washing liquid (i.e. highest level is reached when maximum amount of washing liquid is in the tank and completely frozen) is reached in the tank 100, the upper levels of pipe sections 134a, 134b are above the upper surface of the washing liquid/ice. I.e. when the washing liquid within the tank 100 is completely frozen, there remains a gaseous volume above the upper levels of the pipe sections 134a, 134b. This ensures continuous circulation through the tank 100. In another configuration, the upper level of the outlet pipe 134b may be lower than the upper level of the inlet pipe 134a, but the upper level of the outlet pipe 134b is still higher than the maximum level of the completely frozen washing liquid. In this case, after circulating washing liquid through the tank 100, the tank 100 will empty itself by gravity until the washing liquid reaches the upper level of the outlet pipe 134b.

Fig. 54 is a sectional perspective view of the separation wall and the pipe sections of the evaporator tank of Fig. 52. As shown in Fig. 54, the separation wall may be formed by a first and a second separation wall 137a, 137b. The first separation wall 137a may separate the pipe sections 134a, 134b from each other. Preferably the first separation wall 137a is formed such that the washing liquid entering the evaporator tank 100 is passing over the entire or substantially entire evaporator tank 100 before exiting the tank 100. As shown in Fig. 54, the first separation wall 137a comprises a first portion and a second portion, wherein in particular, when seen the washing machine from a front view, the first portion extends between the pipe sections 134a, 134b parallel or substantially parallel to the front side of the tray element 6c and the second portion extends perpendicular or substantially perpendicular to the first portion to the rear of the washing machine. When seen from a front view, the second portion may extend between the side wall of the tank 100 and the evaporator 102. A gap remains between the second portion and the rear wall of the tank 100 such that the washing liquid can be circulated along a path from the inlet pipe 134a to the outlet pipe 134b, in particular from the inlet pipe 134a along the second portion of the separation wall 137a, along the opposite side of the second portion with the evaporator 102 and along the first portion of the separation wall to the outlet pipe 134b. The separation wall 137a may form a sort of P- shaped path for the washing liquid when looking from a top view at the evaporator tank 100.

The separation wall 137a may comprise at least one recess for receiving one of the mounting elements 108a of the evaporator 102 (as shown for example in Fig. 55D).A portion of the separation wall may be formed by the second separation wall 137b formed in the evaporator tank cover 32. The first separation wall 137a formed in the tank 100 may comprise a recess 139 for receiving a protruding portion of the separation wall 137b formed at the lower side of the evaporator tank cover 32.

In the following different designs of the pipe sections 134a, 134b are described with respect to Figs. 55A to 55F. Accordingly, only the differences between the arrangement shown in Fig. 53 and Figs. 55A to 55F, namely the positioning and the shape of the pipes 134a, 134b, are outlined in the following. Otherwise, the elements and functions as described above with respect to the other elements correspondingly also apply individually, in subgroups or as a functional group to the embodiment of Figs. 55A and 55F.

As already described with respect to Fig. 53, in any of the following embodiments a gaseous volume is always maintained above the pipes 134a, 134b and the pipes 134a, 134b are always above the upper surface of the washing liquid/ice within the tank 100.

Fig. 55A is a perspective view of the upper half of the washing machine of Fig. 5 IB with another arrangement of the pipe sections of the evaporator tank and Fig. 55B is a sectional view of the pipe sections of Fig. 55A. In contrast to the embodiment of Fig.

5 IB, the evaporator tank 100 may have a recess, in particular the bottom of the tank 100 may be shifted upwards in the area of the outlet pipe 134b. As a result, the outlet pipe 134b no longer extends through the entire height of the tank 100.

As shown in Fig. 55B, the outlet pipe 134b is shorter than the inlet pipe 134a, wherein in particular the upper levels are the same, but the lower level of the outlet pipe 134b may have a higher vertical height than the inlet pipe 134a. The outlet 135b defines an outlet level 141b within the evaporator tank 100. The outlet level 141b is a level where the liquid within evaporator tank 100 is flowing out of the evaporator tank 100 if the liquid is above the outlet level 141b and where the liquid stops to flow out of the evaporator tank 100 when the level of the liquid is at or below the outlet level 141b. The inlet 135a defines an inlet level 141a, wherein as shown in Fig. 55B, the inlet level 135a is arranged at the same height as the outlet level 141b. The inlet level 141a is a level where washing liquid is flowing in the evaporator tank 100 if the liquid is above the inlet level 141a and where the liquid stops to flow in the evaporator tank 100 when the level of the liquid is at or below the inlet level 141a.

The inlet/outlet level 141 may be arranged above the upper level of the evaporator 102 within the evaporator tank 100 and/or below the inner surface of a top cover or ceiling of the evaporator tank 100. Preferably, the evaporator tank 100 is only partially filled with the heat exchanging medium and a gaseous volume is maintained above the inlet 135a and outlet 135b. Alternatively, the outlet level 141b may be arranged below the inlet level 141a. Therefore, backflow of the liquid through the inlet pipe 134a is prevented. Further, the liquid may flow out of the evaporator tank 100 through the outlet pipe 134b via outlet 135b until the liquid reaches the outlet level 141b.

Fig. 55C a perspective view of Fig. 55A with another arrangement of the pipe sections of the evaporator tank. The outlet pipe 134b is arranged horizontally or substantially horizontally at the side wall of the evaporator tank 100. Alternatively, the pipe 134b may be arranged inclined at the side wall of the tank 100. In particular, the outlet pipe 134b is arranged at a recess formed at the side wall of the tank 100 (i.e. the outlet 135b is formed at the side wall of the tank 100 in particular by a recess formed in the side wall). This reduces the protrusion of the outlet pipe 134b beyond the remaining side wall of the evaporator tank 100. The lower edge of the outlet 135b (corresponds to the outlet level 141b) of the evaporator tank 100 to which the outlet pipe 134b is connected may have the same level as the upper level of the inlet pipe 134a, in particular as the inlet level 141a (not shown in Fig. 55C but compare Fig. 55F). Thus, the washing liquid entering the tank 100 through the pipe 134a may flow out of the tank 100 through the outlet pipe 134b until the washing liquid reaches the outlet level 141b. Alternatively, the outlet 135b of the tank 100 connected to the outlet pipe 134b may be arranged such that the lower edge of the outlet (i.e. the outlet level 141b) is below the upper level of the inlet pipe 134a (i.e. below the inlet level 141a). As already described with respect to Fig. 53, preferably a gaseous volume is maintained above the pipes 134a, 134b and the pipes 134a, 134b are above the upper surface of the washing liquid/ice within the tank 100.

Fig. 55D is a sectional view of Fig. 55A with another arrangement of the pipe sections of the evaporator tank 100. The pipe sections 134a, 134b in Fig. 55D differ from the pipe sections 134a, 134b in Fig. 55A in that the regions of the pipe sections 134a, 134b outside the evaporator tank 100 are bent, e.g. by 30, 60 or preferably by 90 degrees. Thus, assembling the first and second water regeneration lines 132a, 132b may be easier due to better accessibility.

Fig. 55E is a perspective view of Fig. 55C with another arrangement of the pipe sections of the evaporator tank and Fig. 55F is a sectional view of the pipe sections of Fig. 55E. The inlet pipe section 134a in Figs. 55E and 55F differ from the inlet pipe section 134a in Fig. 55C in that the region of the inlet pipe section 134a outside the evaporator tank 100 is bent, e.g. by 30, 60 or preferably by 90 degrees. Thus, assembling the first water regeneration line 132a may be easier due to better accessibility.

Fig. 56 A is a perspective view of Fig. 47 with another configuration of the tray element and Fig. 56B is a detailed sectional view of the evaporator tank inlet and outlet portion. Only the differences between the arrangement according to Figs. 56A and 56B and the arrangement of Fig. 47 are outlined in the following. Otherwise, the elements and functions as described above with respect to the other elements correspondingly also apply individually, in subgroups or as a functional group to the embodiment of Figs. 56A and 56B.

As shown in Fig. 56A, the tray element 6c comprises an evaporator tank 100 having a first and a second container chamber 35a, 35b. The first and second container chambers are fluidly separated chambers. The chambers 35a, 35b are preferably separated from each other by a separation wall inserted in the evaporator tank 100 between both chambers. The first container chamber 35a houses the evaporator 102 or at least a portion of the evaporator 102 and permanently stores the heat exchanging medium. The second container chamber 35b may be a flow through tank chamber comprising the inlet 130a and the outlet 130b, wherein the second container chamber 35b is in heat contact with the heat exchanging medium in the first container chamber 35 a. The top of the second container chamber 35b may be closed by a cover. Preferably, the separation wall is formed by (or integrated in) the evaporator tank cover 32a. In addition or alternatively, the second container chamber 35b is integrated in the evaporator tank cover 32a. Preferably, the second container chamber 35b comprises washing liquid guiding elements 37 arranged within the second container chamber 35b. The washing liquid guiding elements 37 may be formed in a single piece with the second container chamber, preferably with the evaporator tank cover 32a (i.e. the separation wall) or may be formed as a separate piece which is mounted into the second container chamber 35b (in particular on the separation wall). The evaporator tank cover 32a, in particular with the second container chamber 35b, may be formed as a separate element or in a single piece with the tray element 6c. The evaporator tank 100 or at least the bottom of the tank 100 is formed as a separate element mountable to the tray element 6c. Alternatively, the evaporator tank 100 may be formed in a single piece with the tray element 6c. The evaporator tank cover 32a preferably seals the underlying evaporator tank 100 with the liquid stored therein. Preferably, a gasket is arranged between the evaporator tank cover 32a and the evaporator tank 100. The evaporator tank cover 32a may be mounted detachable e.g. by screws or non-detachable e.g. by welding or gluing. Preferably, the liquid stored in the tank 100 below the heat exchanger 35 is water mixed with at least one additional component such as salt water. The washing liquid guiding elements 35a may form a predetermined path for guiding washing liquid along within the tank 35b of the cover 32a. The evaporator tank cover 32a may comprise a lid 33 for sealing the second container chamber 35b from above. Preferably, a gasket is arranged between the lid 33 and the second container chamber 35b. The lid 33 may be mounted detachable e.g. by screws or non-detachable e.g. by welding or gluing.

As shown in Figs. 56A and 56B, the mixing pump 76 has the same function as shown in the configurations of Figs. 45, 46 and 47. The water which is the washing liquid that was used for washing laundry in the tub is extracted from the tub. The extraction from the tub may be made through an outlet provided at the tub wall or preferably through the sump of the tub or a sump portion fluidly connected to the tub. Preferably the washing liquid is extracted downstream of a filter which is filtering the washing liquid extracted from the tub. The filter can be the filter 68 which is normally provided in the passage from the tub (e.g. from the sump) to the drain pump 72 which is draining the washing liquid e.g. after a washing or rinsing phase. The extracted washing liquid from the tub is guided by the mixing pump 76 through the first water regeneration line 132a and through the pipe 134a which is connected to an inlet 133a into the second container chamber 35b, in particular to the upper side of the evaporator tank cover 32a. The pipe 134a preferably extends through the first container chamber 35a, in particular connects the inlet 130a of the evaporator tank 100 to the inlet 133a of the second container chamber 35b. Thus, the washing liquid is guided through the first container chamber 35a. The second container chamber 35b is preferably in heat contact with the first container chamber 35a, in particular the washing liquid passing the second container chamber 35b is in heat contact with a gaseous volume provided above the heat exchanging medium stored in the first container chamber 35a. Preferably, when the heat exchanging medium within the evaporator tank 100 ices, the gaseous volume is filled by the iced heat exchanging medium and a heat contact between the washing liquid flowing through the second container chamber 35 and the iced heat exchanging medium is obtained. The washing liquid may flow along the washing liquid guiding elements 35a which are in thermal communication with the first container chamber (i.e. below the second container chamber) and the heat exchanging medium stored therein. While flowing along the washing liquid guiding elements 35a, the heat of the warm washing liquid is transferred to the heat exchanging medium stored in the first container chamber 35a which in particular results in the melting of the ice in the first container chamber 35a. The cold washing liquid exits the second container chamber 35b, in particular the upper side of the evaporator tank cover 32a, through outlet pipe 134b connected to outlet 133b. The pipe 134b preferably extends through the first container chamber 35a, in particular connects the outlet 133b of the second container chamber 35b to the outlet 130b of the evaporator tank 100. Thus, the washing liquid is guided through the first container chamber 35a. The washing liquid may flow from the outlet 130b through the second water regeneration line 132b back into the tub or the sump fluidly connected to the tub or another fluid line connected to the tub (e.g. the detergent housing or a passage from the detergent drawer to the tub. Alternatively, the washing liquid is passed into a drain line 70 that is used by the drain pump 72 for draining washing or rinsing liquid at least partially. Preferably, after draining of the washing liquid from the second container chamber 35b, new warm washing liquid is sucked from the tub and recirculated through the second container chamber 35b. Alternatively, the second water regeneration line 132b may be connected directly to the tub of the washing machine.

Fig. 57 is a schematic diagram of the functional elements used for heating and cooling the washing liquid during circulation of the washing liquid in the washing machines described above. As already described above, the washing liquid is circulated in the washing liquid circulation unit 64 and the refrigerant is circulated in the refrigerant circulation circuit 42.

In Fig. 57 the washing liquid flow direction 96 and the refrigerant flow directions 94 are indicated by arrows. Starting from a sump 140, in particular from a drain manifold which is arranged at the lower part of the sump 140 of the tub 58, the first water circulation section 64a connects to the inlet of the circulation pump 66. Exiting the circulation pump 66 through the circulation pump outlet, the washing liquid is directed to the condenser 81 via the second water circulation section 64b. The washing liquid flows within the condenser 81 through the third water circulation section 64c. There are two operation modes: First the heating of the washing liquid used e.g. during a washing phase of a washing cycle and second the cooling of the washing liquid used e.g. for de-icing the evaporator, in particular during a rinsing (e.g. the last rinsing phase) of a washing cycle. The heating of the washing liquid is stopped for example if the heat transfer to the washing liquid is no longer required or possible (e.g. no circulation, washing liquid maximally heated and/or heat exchanging medium maximally depleted of heat (frozen)). Heat (e.g. residual heat of the heat pump) may be deposited in the evaporator tank during phases when washing liquid is not to be heated. This redeposited heat can be extracted in the next washing cycle for heating the circulated liquid.

The washing liquid flow direction 96 and the refrigerant flow directions 94 are indicated by arrows in Fig. 57.

In the heating mode, within the refrigerant circulation circuit 42, starting from the refrigerant condenser outlet 88, the refrigerant is directed by the first refrigerant circuit section 44a through the expansion device 40 to the evaporator 102. The compressor 36 arranged within the refrigerant circulation circuit 42 creates a vacuum applied to the evaporator 102. The heat exchanging medium in the evaporator tank 100 is in heatexchanging contact with the evaporator 102. The medium is cooled down and finally changes from the liquid to the solid phase for releasing heat. The heat released heats the refrigerant in the evaporator 102 which then evaporates. The heated refrigerant as a gas phase is sucked by the compressor 36 through the second refrigerant circuit section 46a, the switching valve 78 and the third refrigerant circuit section 48a. The compressed refrigerant is passed through the fourth refrigerant circuit section 50a, the switching valve 78 and fifth refrigerant circuit section 52a to the condenser 81 through the refrigerant condenser inlet 86. Within the condenser 81, the refrigerant and the washing liquid flow in opposite directions for an improved heat exchange. In the condenser the washing liquid is heated by transferring the heat from the refrigerant to the washing liquid. From the refrigerant condenser inlet 81 to the refrigerant condenser outlet 88, the refrigerant cools down and from the washing liquid condenser inlet 82 to the washing liquid condenser outlet 84, the washing liquid is heated.

The heated washing liquid exits the condenser 81 through the washing liquid condenser outlet 84 and the further flow path of the washing liquid may optionally be selected by a first flow diverter 144A. The first flow diverter 144A may in a first state selectively direct the washing liquid to the tub 58 through the water inlet 65 or in a second state selectively to the drawer housing 12a. Instead of providing the first flow diverter 144A, the circulated washing liquid may also be passed from the condenser outlet 84 to the drawer housing 12a.

From the drawer housing 12a the washing liquid flows into a manifold 146 which may optionally comprise a second flow diverter 144B (instead or in addition to the first flow diverter 144A). The second flow diverter 144B may selectively direct the washing liquid through the fourth water circulation section 64d and the water inlet 65 to the tub 94. The washing liquid flows through the sump 140 out of the tub and is circulated again as described above. At the end of the washing cycle, the washing liquid which exits the tub 58 through the sump 140, in particular from a drain manifold which is arranged at the lower part of the sump 140, is drained by the drain pump 72 through the water drain 70.

In the cooling mode for de-icing the evaporator at the end of a washing cycle or if for example the heat transfer to the washing liquid is no longer required or possible (e.g. no circulation, washing liquid maximally heated) then the residual heat of the heat pump may be deposited in the evaporator tank so that this heat can be extracted in the next washing cycle for heating the circulated liquid, the refrigerant flow direction is reverted as indicated by the white filled arrows in Fig. 57 (the black filled arrows indicate the normal flow direction for the heating process of the washing liquid). The reversal of the refrigerant flow through the condenser 81, expansion device 40 and evaporator 102 is provided by a refrigerant flow changing device 78. In refrigerant flow reversal mode the evaporator 102 works as a condenser and heats the heat exchanging medium within the evaporator tank 100. The condenser 81 operates as an evaporator and cools the circulated liquid (which is preferably freshly supplied tap water and/or water from the previous rinsing). The expansion device 40 preferably is a dual-direction expansion device, e.g. a capillary that operates independent of the flow direction.

The cooled washing liquid exiting the condenser 81 may be directed through the first flow diverter 144A to the drawer housing 92 in the fourth water circulation section 64d. Then the washing liquid may flow to the second flow diverter 144B in the manifold 146 and from there to the water inlet 65. From the water inlet 65 the liquid may flow into the tub 58 and then to the tub sump 140 and can be drained with the drain pump 72 which is connected to the sump 140, in particular to the drain manifold of the sump 140, through the water drain 70 e.g. after the de-icing of the evaporator 102. The flow changing device 78 has two switching states, wherein the refrigerant conveyance direction of the compressor 36 is not changed in both switching states. a) In a first state (normal operation state for the heat pump, heating mode as described above) the evaporator 102 operates as evaporator and the condenser 81 operates as condenser. The refrigerant compressed by the compressor and coming from the compressor outlet is directed by the switching valve 78 to the condenser 81. The refrigerant from the evaporator 102 is sucked in through the switching valve 78 to the compressor inlet. b) In a second state (refrigerant flow reversal, cooling mode as described above) the refrigerant compressed by the compressor is directed by the switching valve 78 to the evaporator 102. The refrigerant exiting the condenser is sucked in by the compressor 36 through the switching valve 78 being in its second switching state.

Further, a heater 142 may be arranged inside the tub 58, preferably at the bottom of the tub 58, for heating the washing liquid. The washing machine 2 may have the mixing pump 76 that drains water and detergent from the sump 140, in particular from the drain manifold which is arranged at the lower part of the sump 140, at the beginning of a washing cycle after detergent has been introduced into the tub 58 and re-send the water and detergent to the sump 140, in particular to the tub 58 below the water heater 141. Thereby, the mixture and dissolution of the detergent in the water can be improved and accelerated.

The functional arrangement shown in Fig. 57 is applicable to all above embodiments of a laundry treatment machine. In particular applicable in all embodiments of a washing machine which are disclosed herein in more detail. Although not shown in the detailed embodiments above, for example the first and/or second flow diverter 144 A, 144B may be provided.

In Fig. 57, the condenser 81 is schematically depicted in a rectified (non-bend) state also to exemplify the relation of longitudinal extension L to cross extension Q. The longitudinal extension L of the condenser is a multiple of the cross-extension Q. In the examples here the cross-section of the condenser 81 is circular - see Fig. 15. Even if the cross-section should not be circular, the cross-section extension Q considered here for the length/cross extension ratio R is the maximum cross extension of the condenser (considered without the outer insulator 122). In these embodiments the longitudinal extension along the flow path of the refrigerant is the same or basically the same (within a tolerance in length difference of e.g. +/- 10% or within +/- 5% or within +/- 3%) as the longitudinal extension of the flow path of the conduit 64c that is guiding the washing liquid from the inlet 82 to the outlet 84.

It should be clear to the skilled person that the different configurations of the evaporator tank 100, the evaporator 102, the condenser 81 and the switching valve 78 described above are also applicable to a washer dryer as e.g. shown in Fig. 58.

Fig. 58 is a perspective view of a washer dryer without the tray element and the casing. The drying air circulation circuit 150 comprises a flow channel (not shown), which may be arranged at a tub rear wall of the tub 58 connected to an inlet of a blower, a blower 152a and the return duct 152b comprising a heater element 152c. The blower, the return duct 152b and the heater element 152c are preferably arranged in the upper region of the washer dryer 147, e.g. below a top module (not shown). At the rear wall, the drying air enters from the tub interior through an opening in the tub into the flow channel which may have a vertical portion e.g. on the right side of the tub backwall and then continues into a left curve in the upper region of the tub 58 and then connects to the inlet of blower. Return duct 152b connects the blower outlet to an opening in the gasket 62.

The air is circulated by the blower 152a, heated within the return duct 152b and may be directed into the drum 60 through the top of the bellow 62. In the tub the heated air absorbs the moisture from the laundry within the drum 60 and exits the tub through the flow channel at the tub rear wall. In the flow channel, the heated air comprising the moisture of the laundry is cooled by an air condensation unit (not shown). The air may be cooled inside the flow channel by the circulated washing liquid which optionally may be cooled inside the condenser 81 during a drying cycle (see below reverse operation of the heat-pump).

The washing liquid may be directed from the washing liquid condenser outlet 84 through a detergent drawer housing water inlet 148 and may enter on the right side the preferably vertical condensation region of the flow channel in the tub rear wall via the tub water supply (not shown). The washing liquid falls down the condensation region of the flow channel and the counter-flowing drying air with moisture is cooled by the washing liquid and humidity from the drying air is condensed. After passing the air condensation unit, the dry air passes the blower 152a, the air is heated by the heater element 152c and the air circulation repeats. The condensate of the air condensation unit together with the circulated washing liquid is directed back to the tub 58. Of course, during drying operation, the 'washing liquid' is preferably water which was introduced as tap water and/or e.g. water that remained from the previous rinsing step. The blower 152b may be driven by a separate motor or by the motor for driving the drum 60.

The washer dryer of Fig. 58 preferably provides two different operation modes for the heat-pump system. In the first operation mode of the heat-pump system the operation is equal to the 'heating mode' described according to Fig. 57 for the washing machines in which the washing liquid is circulated in a washing liquid circulation unit 64 and heated in the condenser 81 arranged in the top module. The refrigerant which preferably flows in the condenser outer tube 120 heats the washing liquid passed through the condenser inner tube 118 (see: Fig. 18). I.e. the refrigerant and the circulated washing liquid are in counter-flow, the condenser operates as condenser and heats the washing liquid. The evaporator operates as evaporator and extracts heat from the medium in the evaporator tank.

In a second operation mode of the heat pump of the washer dryer system the operation may be equal to the 'cooling mode' described according to Fig. 57 for the washing machines in which the refrigerant flow is reversed by the switching valve 78 (described above according to the Figures showing washing machines) such that the condenser 81 operates as evaporator and the evaporator 42 operates as condenser. In this mode, the residual heat of the washing liquid may be used for de-icing the evaporator at the end of a washing cycle or if for example the heat transfer to the washing liquid is no longer required or possible (e.g. no circulation washing liquid maximally heated) then the residual heat of the heat pump may be deposited in the evaporator tank so that this heat can be extracted in the next washing cycle for heating the circulated liquid.

The switching between the operation modes of the heat-pump system and the way in which the washing liquid is heated during a washing cycle and is cooled during a drying cycle within the condenser 81 are described in detail with respect to Fig 57.

In addition or as an alternative to the second operation mode described above, during a drying cycle of the washer dryer, the washing liquid may be cooled within the condenser 81 and then used for the condensation in the air condensation unit e.g. at the tub rear wall. Reference Numeral List

2 washing machine

4 cabinet

5, 5a, 5b, 5c top module

6, 6a, 6b, 6c, 6dtray element

7 peripheral outer side (wall)

8 front wall

9, 9a top wall (work top)

10 side wall

12 detergent drawer

12a drawer housing

13 handle

14 control panel

16 loading opening

18 door

20 air inlet opening

22, 22a service cover/ filter opening

24 rear wall/back-wall

28 balance weight

30 spring dampers

31 insulation layer of evaporator tank cover

32, 32a evaporator tank cover

33 lid for evaporator tank cover

34 seat/ribs for receiving thermo-insulating material

35a, 35b first / second container chamber

36 compressor

37 washing liquid (separation) guiding element

38 insulation layer of evaporator tank

40 expansion device (capillary or expansion valve)

42 refrigerant circulation circuit

44a, 44b,

44B, 44C, 44D first refrigerant circuit section (between refrigerant condenser outlet and evaporator inlet, considering the heat pump refrigerant flow direction)

46a, 46b, 46B, 46C, 46D second refrigerant circuit section (between evaporator outlet and first inlet of switching valve, considering the heat pump refrigerant flow direction)

48a, 48B, 48C,

48D third refrigerant circuit section (between first outlet of switching valve and compressor inlet, considering the heat pump refrigerant flow direction)

50a, 50B, 50C,

50D fourth refrigerant circuit section (between compressor outlet and second inlet of switching valve, considering the heat pump refrigerant flow direction)

52a, 52B, 52C,

52D fifth refrigerant circuit section (between second outlet of switching valve and condenser inlet, considering the heat pump refrigerant flow direction)

54a, 54b sixth refrigerant circuit section / condenser outer tube (within outer tube of the condenser)

56 bottom

58 tub

60 drum

62 bellow / gasket

63 inlet (nozzle) into tub for water from evaporator tank

64 washing liquid circulation unit

64a, 64a* 64A, 64A* first water circulation section (between tub outlet (e.g. via the sump) and inlet of circulation pump, considering the washing liquid flow direction)

64b, 64b*, 64B, 64B* second water circulation section (between outlet of circulation pump and outlet of condenser, considering the heat pump refrigerant flow direction)

64c, 64c* third water circulation section / condenser inner tube (within condenser) 64d, 64d* fourth water circulation section (between condenser inlet and water inlet to tub, considering the heat pump refrigerant flow direction and water inlet)

65 water inlet into tub (nozzle)

66 circulation pump (jet pump)

66a circulation pump inlet

66b circulation pump outlet 68 filter / service opening

70 water drain / drain hose

72 drain pump

74 tub outlet (e.g. via the sump)

76 mixing pump / chamber circulation pump

77 return line to tub

78 switching element / switching valve / refrigerant flow changing device

78a, 78b first/second inlet of switching valve

79a, 79b first/second outlet of switching valve

79 opening for tub transport lock

80 transport lock for compressor

81, 81a, 81b, 81c condenser

82 washing liquid condenser inlet

84 washing liquid condenser outlet

86 refrigerant condenser inlet

88 refrigerant condenser outlet

90 mounting bracket (for compressor)

92 damping element / vibration dampers

94 refrigerant flow direction

96 washing liquid flow direction

100 evaporator tank

100a upper region of evaporator tank

100b lower region level of evaporator tank

100c intermediate region between upper region and lower region

102 evaporator

102a first portion of evaporator

102b second portion of evaporator

104 evaporator inlet

106 evaporator outlet

107 opening for evaporator tank

108, 108a mounting element (for evaporator)

110 compressor inlet

112 compressor outlet

114 gaseous (air) volume in evaporator tank

116 microchannel arrangement

116a microchannel elements

116b inlet distribution channel 116c outlet collection channel

118 condenser smaller/inner tube (washing liquid)

120 condenser larger/outer tube (refrigerant)

122 condenser insulation layer/heat insulating layer

124 microchannels

126 connection element

126a, 126b first / second end portion

128 maintenance opening

130a evaporator tank inlet (or outlet)

130b evaporator tank outlet (or inlet)

132a first water regeneration line (to evaporator tank)

132b second water regeneration line (from evaporator tank)

133a, 133b inlet / outlet of second chamber container

134a, 134b first / second pipe section for guiding water within evaporator tank

135a, 135b inlet / outlet of evaporator tank (flow-through tank)

136 washing liquid (separation) guiding element

137a, 137b first / second separation wall for guiding water within tank

138 fixing element for evaporator pipes

139 recess for receiving second separation wall of tank cover

140 tub sump

141a, 141b inlet / outlet level within evaporator tank

142 water heater

144A, 144B first/second flow diverter / washing liquid directing device (optional)

146 manifold

147 washer dryer

148 drawer housing water inlet

150 tub water supply

152 drying air circulation circuit

152a blower

152b return duct

152c heater element

L longitudinal extension cross extension/dimension