| JP04371372 | WELDING METHOD FOR HEAT TREATED AND REINFORCED STEEL SHEETS |
| JP58107281 | WELDING GUN DEVICE |
| JP58202982 | SPOT WELDING DEVICE |
BUOSI, Augusto (Corso Lino Zanussi 30, Porcia, I-33080, IT)
VELLI, Vittorio (Corso Lino Zanussi 30, Porcia, I-33080, IT)
BENI, Marco (Corso Lino Zanussi 30, Porcia, I-33080, IT)
BUOSI, Augusto (Corso Lino Zanussi 30, Porcia, I-33080, IT)
VELLI, Vittorio (Corso Lino Zanussi 30, Porcia, I-33080, IT)
| CLAIMS 1. A cooling apparatus for food storage (100), in particular a refrigerator or a freezer, comprising a defrosting apparatus including a regulating device of a fluid flow through an orifice (212), said device comprising a fluid interception member (220) being associated to the orifice, responsive to the fluid pressure and having: a first operative configuration corresponding to a pressure value of the fluid lower than a predetermined value, in said first operative configuration the interception member closing the orifice in order to prevent the passage of the fluid, and a second operative configuration corresponding to a pressure value of the fluid at least equal to said predetermined pressure value, in said second operative configuration the interception member opening the orifice in order to allow the passage of the fluid, characterized in that said device is configured in such a way that the return of the interception member from the second to the first operative configuration relies on the action of the gravity force naturally acting on the interception member itself. 2. Cooling apparatus according to claim 1, further comprising a tubular portion defining said orifice, said interception member being hinged to said tubular portion so as to move towards said second operative configuration due to the fluid force and towards said first operative configuration due to its own weight. 3. Cooling apparatus according to claim 1 or 2, further comprising: a first tubular portion (200) associatable with a drainage tube (120) of the fluid for receiving such fluid, and a second tubular portion (210) transversely connected to said first tubular portion and comprising the orifice at a free end thereof. 4. Cooling apparatus according to claim 3, wherein the interception member is hinged at a side thereof to a support (215) associated with the second tubular portion, said support allowing the interception member to freely rotate with respect to the hinged side from the first operative configuration to the second operative configuration, and vice-versa. 5. Cooling apparatus according to claim 3 or 4, wherein the orifice has an oblique section with respect to a vertical axis. 6. Cooling apparatus according to claim 5, wherein said oblique section of the exhaust orifice has an inclination with respect to the axis (X) of the second tubular portion between 0° and 90°. 7. Cooling apparatus according to any claim from 3 to 6, wherein the axis of the first tubular portion (Y) has an inclination with respect to the axis of the second tubular portion (X) between 90° and 160°. 8. Cooling apparatus according to any claim from 3 to 7, wherein the first and second tubular portions, the support and the interception member are made of plastic materials. 9. Cooling apparatus according to claim 5, wherein the predetermined value of pressure depends on at least one parameter chosen from: inclination of the axis of the first tubular portion with respect to the axis of the second tubular portion, inclination of the oblique section of the exhaust orifice with respect to the axis of the second tubular portion, and material and/or weight of the interception member. 10. Cooling apparatus according to any of the preceding claims, wherein the device includes a fastening appendix (205), said fastening appendix comprising hook elements (207) for the fastening to an edge portion of a vessel. |
The present invention generally relates to the field of cooling apparatuses, for example for food storage. More specifically, the present invention relates to a cooling apparatus, such as a refrigerator or freezer, including a new solution for defrost liquid draining.
As known, the cooling of the inner compartment of a refrigerator or freezer occurs by means of a refrigeration cycle. The most used refrigeration cycle is the so- called compression refrigeration cycle, which allows cooling the air within one or more compartments of the apparatus, which are intended to accommodate the food to be stored, thus allowing the storage thereof even for a relatively long time.
In the compression refrigeration cycle, the refrigerant fluid (or refrigerant), thanks to the property of evaporating at relatively low temperatures, may be subject to a number of changes (including phase changes) so as to perform heat exchanges intended to subtract thermal energy from the compartment to be cooled, and transferring the subtracted thermal energy to the surrounding environment. In particular, the gaseous refrigerant is first compressed by a device, called compressor, in order to increase both temperature and pressure thereof, and then, by means of a device called condenser, such compressed refrigerant gas is cooled, by subtracting heat therefrom, and then brought to liquid phase. Subsequently, by means of a thermal expansion member (generally an expansion thermostatic valve), or a capillary, the refrigerant liquid is injected into an evaporator, wherein, once expanded and returned to the gaseous phase, it absorbs thermal energy from the inner environment of the compartment to be cooled; the refrigerant gas is finally returned to the compressor for starting a new cycle, until the compartment to be cooled reaches a desired temperature and a thermostat stops the compressor.
As known, during such refrigeration cycle, there is the frequent possibility that a certain amount of frost forms on the evaporator, which could cause a non optimal functioning of the devices of the cooling circuit, and thus reduce the thermodynamic efficiency of the refrigeration cycle.
In modern refrigerators and freezers the thermodynamic efficiency is improved through the recourse to ventilated systems (so-called "no-frost"), which provide for the forced circulation of air within the compartment containing the evaporator. However, such air cools quickly and generates moisture, thereby causing undesirable ice accumulation on the evaporator that, besides reducing the section of air passage, reduces the performance of the evaporator itself and limits the thermal exchange thereof. In order to reduce such drawback, no-frost control systems are used, which run periodic defrost cycles of the evaporator. Such systems typically rely on the use of a heating device properly positioned and controlled (through controllers that implement algorithms and configurations of the defrost cycle) for slightly heating the evaporator, so as to cause the melting of the frost formed thereon.
In this way defrost water is formed that results from the melting of the frost to a greater extent compared to apparatuses provided with conventional technology (not "no-frost"), which defrost water is typically piped and collected within a pan placed under the evaporator. Through a drain pipe (for example, of the corrugated type) provided with a valve at its end, such de-frost water is channelled into a vessel, which is usually located close to the compressor, for example immediately above it, so as to exploit the heat generated during operation of the compressor in order to encourage evaporation thereof.
However, the known no-frost systems have some drawbacks. In particular, the water drain pipe may be affected by malfunctions that reduce the thermodynamic efficiency of the refrigeration cycle. In fact, in the above-mentioned periodic defrost cycles, wherein the water defrosted from the evaporator is made to flow into the drain pipe, if the valve proximate to the outlet of the pipe does not open properly, due to intrinsic defects or design errors, the water will not find a suitable outlet, it will completely fill the pipe and flow inside, thereby wetting the food, or it will form a never-ending ice block that will compromise the operation of the apparatus, thereby preventing it from properly regulating the temperatures. If, on the contrary, the end of the pipe remains always open, for example due to a failure of said valve to close properly when required, such condition could promote the passage of moisten-laden air through the pipe and the consequent improper ice accumulation in the proximity of the drainage with results similar to the former case.
In the present state of the art, the refrigerators and freezers provided with the no-frost system mostly make use of two solutions for preventing defrost vapour backflow into the drain pipe; a first solution provides the connection of a siphon to a bottom end of the drain pipe, so that the de-frost water that naturally tends to remain inside the siphon (just by virtue of its shape) acts as a "hydraulic plug" for preventing the vapour backflow. However such solution has the drawback that it does not ensure a proper operation in certain conditions, since the presence of water inside the siphon is not always ensured; this may happen, for example, in the first operation cycle of the refrigerator or freezer (when no de-frost water is present) and/or in case of evaporation of the de-frost water accumulated within the siphon because of excessively high operating temperatures of the compressor. In addition, the siphon, in certain conditions, may act as a source reservoir of moist air, that, by going up to the pipe, could form ice plugs.
A second solution, instead, provides for the use of membrane valve systems, for example a soft membrane (usually made of rubber), which is closed in a rest position thereof, and deforms, opening, as soon as a sufficient amount of water abuts thereon (thus allowing the passage of water through the membrane and its outflow to the collecting vessel). Such solution, however, has non-negligible drawbacks, such as for example the aging of the membrane material (that results in an increased resistance to deformation, or even a breakage thereof), difficulties to have well- defined tolerance values for the amount of water required to determine the opening of the membrane, and "noise" problems that can occur when vibrations (for example, due to the closing of a door for accessing the refrigerator compartment) cause spurious openings of the membrane, and therefore unwanted backflow of the de-frost vapour.
An improvement based on the idea of the second solution described above is shown in the document WO 2006/067767.
Although in principle it has a certain effectiveness, such solution has however a drawback that limits its use in modern applications, wherein reliability of the devices of the refrigerator, and hence of the refrigerator itself, is of the utmost importance for ensuring high operation quality even under intensive use conditions. In particular, in the cited document the end of the drain pipe is vertical, and a flap valve is associated with the discharge opening of the pipe, which flap valve is closed and arranged horizontally in the rest condition, whereas it opens when a sufficient amount of de-frost water is present within the pipe, due to the water weight. Because of its location, a mechanism of return towards the closed position must be combined with the valve, such as a spring return mechanism,; such a mechanism, by opposing to the force of gravity, allows the valve returning to the horizontal rest condition. The use of such a return mechanism limits the use of such solution in systems that require high reliability of the no-frost system; in fact, the proper operation of the valve is strictly connected to the correct and stable operation of the return spring, which however cannot be ensured. In fact, after a certain number of stresses, the return spring may undergo, in a relatively short time of operation of the refrigerator, to an unpredictable alteration of its elastic and deformation properties (e.g., a hardening or a loosening thereof), thereby causing spurious openings and closures of the valve that allow the de-frost vapour penetrating and backflowing into the drain pipe or prevent water from flowing properly.
Moreover, the spring mechanism, even when operating properly, inherently causes valve bounces (due to the inevitable return oscillations of the spring), thereby causing also in this case possible de-frost gas infiltrations.
In any case, having to provide the return mechanism is disadvantageous, since this results in an additional component to be purchased and assembled.
In view of the state of the art so far shown, it is an object of the present invention to overcome the cited drawbacks.
According to the present invention, the defrost apparatus comprises a flux regulating device provided with a fluid interception member, in particular a drain valve; such member is sensitive to the pressure of the fluid itself and has two operative positions, a closing position and an opening position, taken according to the fluid pressure, and it is adapted to pass from the opening position to the closing position under the effect of its own weight force.
Thanks to the present invention, as soon as the defrost water reaches such an amount to exert a pressure at least equal to a predetermined value, the drain valve opens (under the action of such a pressure), thereby allowing the flowing of the defrost water from the drain pipe to the vessel in an easy and effective way; when all the defrost water present within the drain pipe is flown, the valve automatically closes for effect of its own weight, i.e., under the action of the gravity force naturally acting thereon and by nature immutable over time, thus preventing the vapour possibly present near the valve to flow back to the evaporator. The valve, after closing, remains closed until the amount of defrost water accumulated within the pipe is such as to exert a pressure lower than the predetermined value.
The present invention thus relates to a cooling apparatus for food storage, in particular a refrigerator or a freezer, comprising a defrosting apparatus including a regulating device of a fluid flux through an orifice, said device comprising a fluid interception member being associated to the orifice, responsive to the fluid pressure and having:
a first operative configuration corresponding to a pressure value of the fluid lower than a predetermined value, in said first operative configuration the interception member closing the orifice in order to prevent the passage of the fluid, and
a second operative configuration corresponding to a pressure value of the fluid at least equal to said predetermined pressure value, in said second operative configuration the interception member opening the orifice in order to allow the passage of the fluid, the flux regulating device being configured in such a way that the return of the interception member from the second operative configuration to the first operative configuration is entrusted to the action of the gravity force naturally acting on the interception member itself.
In a preferred embodiment, the cooling apparatus further comprises a tubular portion defining said orifice, said interception member being hinged to said tubular portion so as to move towards said second operative configuration due to the fluid force and towards said first operative configuration for effect of its own weight.
In particular, the cooling apparatus may comprise:
a first tubular portion associatable with a drainage tube of the fluid for receiving such fluid, and
a second tubular portion transversely connected to said first tubular portion and comprising the orifice at a free end thereof.
The interception member may be hinged at a side thereof to a support associated with the second tubular portion, said support allowing the interception member to freely rotate with respect to the hinged side from the first operative configuration to the second operative configuration, and vice-versa.
Said orifice may have an oblique section with respect to a vertical axis.
Preferably, such oblique section of the exhaust orifice has a tilt (inclination) between 0° and 90° with respect to the axis of the second tubular portion.
Moreover, the axis of the first tubular portion may have a tilt between 90° and
160° with respect to the axis of the second tubular portion (X).
Preferably, the first and second tubular portions, the support and the interception member are made of plastic materials.
Advantageously, the above predetermined pressure value depends on at least one parameter chosen among:
tilt of the axis of the first tubular portion with respect to the axis of the second tubular portion,
tilt of the oblique section of the exhaust orifice with respect to the axis of the second tubular portion, and
- material and/or weight of the interception member.
The flux regulating device may further include a fastening appendix, which may comprise hook elements for the fastening to an edge portion of a vessel.
These and other features and advantages of the solution according to the present invention will be better understood with reference to the following detailed description of possible embodiments thereof, given purely by way of non-limiting example, to be read in conjunction with the attached drawings. In this regard, it is expressly understood that the drawings are not necessarily drawn to scale and that, unless otherwise indication, they are simply intended to conceptually illustrate the described structures and procedures. In particular:
Figure 1 schematically shows a refrigeration apparatus seen from behind, provided with a valve according to an embodiment of the present invention;
Figure 2 shows a cross-section of a detail of Figure 1 including a drain valve according to an embodiment of the present invention, and
Figures 3A-3B show a perspective view of the valve of Figure 2 in two different operative configurations.
With particular reference to the drawings, in Figure 1 there is shown a refrigeration apparatus 100, for example a household refrigerator or freezer, seen from behind. For the sake of convenience, in the following of the description reference will be always made to a refrigerator, but it is clear that any consideration may be extended to a freezer.
The refrigerator 100 is, for example, adapted to perform a compression refrigeration cycle of a known type; for this reason, for the sake of exposition simplicity and clarity, in the following there will be introduced and explained only some peculiarities of the refrigerator (and its operation) necessary to circumscribe the basic idea of the present invention from the implementation and functional point of view.
The refrigerator 100 includes an evaporator 105 for allowing the evaporation of a refrigerant fluid, and a compressor 110 for allowing a compression of such refrigerant fluid in order to facilitate a next condensation phase of the refrigerating cycle.
A tray 115 is present under the evaporator 105 for collecting water deriving, for example, by a defrosting process of the evaporator, and to which reference will be made hereafter as "de-frost water". Such tray 115 is connected to a drain pipe 120 (e.g., of the corrugated type), which conveys the de-frost water drained within the tray 115 to a vessel 125 advantageously located above the compartment wherein the compressor 110 is housed. The location of the vessel 125 is such that the evaporation of the defrost water drained therein is facilitated by the heat produced by the compressor 110 below. An end portion of the drain pipe 120 is hydraulically coupled to the vessel 125 through a drain valve (represented in the figure as a generic functional block and denoted by the reference 130), whose purpose is to allow the flow of the defrost water towards the vessel 125 and to prevent that, once the water has flowed, the steam generated by evaporation of the defrost water goes up the drain pipe 120, and possibly reaches the evaporator. Moreover, in this way it is prevented that, in the absence of defrost water to be discharged, moist air resulting from other processes of the refrigerating cycle or from external atmospheric conditions goes up through the drain pipe 120 thereby reaching the evaporator 105.
As visible in Figure 2, the valve 130, in the practical example herein considered, includes a valve body 203, for example made of plastic material, comprising a tubular portion 200, whose top end is adapted to be coupled to the terminal portion of the drain pipe 120 afferent to the vessel 125; for example, the upper end of the tubular portion 200 can be sized and shaped in such a way that it can be inserted into the end portion of the drain pipe 120.
The tubular portion 200 is substantially vertical in the example, and at its lower end it is connected transversally, according to a determined angle with respect to the vertical, to another tubular portion 210; the body 203 of the drain valve has hence substantially an "L" shape (with a curve that is formed at the connection of the two tubular portions 200 and 210).
The valve 130 is preferably fixed to the vessel 125. In a possible embodiment, the valve 130 is fixable to the vessel 125 by a fixing appendix 205 of the body 203 of the valve, appendix 205 that includes hook projections 207 adapted to engage reversibly an edge portion of the vessel 125.
As visible in the figure and mentioned just above, the axis X of the tubular portion 210 is not aligned with the axis Y of the tubular portion 200, but with respect to the latter it has a predefined tilt; in quantitative terms, the angle a between the respective X and Y axes of the tubular portions 200 and 210 is preferably between 90° and 160°, still more preferably between 95° and 120°, such as 100° (as shown in the figure).
The free end of the tubular portion 210 (which defines an exhaust orifice 212 of the defrost water) has an oblique cross section that forms a determined angle β with respect to the axis X of the tubular portion 210: in particular, the angle β can be preferably between 10° and 90°, still more preferably between 30° and 60°, for example 45° (as depicted in the embodiment shown in the figure).
On the body 203 of the drain valve 130, and particularly on the tubular portion 210, a fork-shaped support 215 is formed to which a fluid interception element or closure element or door 220 is freely hinged, for the selective closure of the exhaust orifice 212; in this way, the door 220 has substantially only one degree of rotational freedom with respect to the hinged side. Such rotational degree of freedom given to the door 220 ensures to the valve 130 substantially two operative configurations, an opening one and a closing one of the exhaust orifice 212. Moreover, at the junction between the tubular portions 200 and 210, a protruding appendix 225 is present, integrally formed with the body 203 of the valve 130 or subsequently assembled thereto, adapted to act as limit stop in such a way to limit the opening of the door 220 when the valve is in the opening configuration (as will be better explained in the following).
The movement of the door 220 from the closed position to the opening one and vice-versa is advantageously determined by a combination of resulting forces given by the vector sum of forces (gravitational force acting on the door, pressure of the defrost water at the orifice 212, as well as passive forces such as the reaction forces acting on the door 220 and the various frictions).
In particular, in the closing configuration of the valve 130 (shown in the Figure 3A), in the tubular portion 210, at the orifice 212, there is no defrost water, or otherwise, even if there is water, the amount of defrost water accumulated is so small to exert a pressure on the door 220 below a predetermined value (as will be discussed in the following), and therefore the door 220 keeps the exhaust orifice 212 of the tubular portion 210 closed, by completely covering it (thereby preventing the vapour generated by the defrost water from flowing into the drain pipe 120 towards the evaporator 105).
Instead, in the opening configuration (shown in the Figure 3B), the amount of defrost water from the drain tube 120 and accumulated at the orifice 212 is such as to exert on the door 220 a pressure grater than said predetermined value, and therefore the door, by turning with respect to its hinged side, uncovers the exhaust orifice 212, thereby allowing the defrost water to flow into the vessel 125 below.
Thus, the door 220 is automatically and naturally caused to return, for effect of its weight force, towards the closed position, wherein it rests on the edge of the exhaust orifice 212, closing it. It should be noted that in case of excessive defrost water pressure exerted on the door 220, the opening of the latter is conveniently limited by the stop limit element 225; in this way, it is prevented that the door 220 remains stably blocked in an extra-rotation position such that it can no longer be returned by the weight force to the closed configuration. Once it has been closed, the door 220, still for effect of its weight force, then remains firmly abutting the edge of the orifice 212.
It should be noted that in order to achieve the aforementioned objectives, the angle γ between the plane Z wherein the edge of the exhaust orifice 212 lies and a vertical plane should be between 0° and 90°, and preferably between 15° and 60°. This is to the end of ensuring that the weight force acting on the door 220, which naturally tends to bring the door in a vertical position, brings the door itself to rest on the edge of the exhaust orifice 212, and also that the component of the weight force acting on the door directed perpendicularly to the plane wherein the edge of the orifice 212 lies is sufficient to keep the orifice 212 closed (and also avoiding rebounds) unless when there is a sufficient amount of defrost water to be discharged.
The drain valve 130 is instead kept open as long as there is a quantity of defrost water to be discharged sufficient to exert on the door 220 such a pressure to overcome the weight force acting thereon. Preferably, the sizing of the drain valve 130 in terms of weight of the door 220 and the angles between planes and axes is such as to minimize the amount of stagnant water in the valve; the predefined tilt of the tubular portion 210 with respect to the tubular portion 200 makes it possible to avoid that even small amounts of defrost water flowing through the valve body stagnate at the bend.
Such solution also has a significant advantage in terms of reconfigurability, as the predetermined amount of water flow can be set in a reliable and precise way by acting properly on design parameters that can be selected during manufacturing phase; for example, it is possible to act on weight and/or material of the door 220, on the respective tilt of the axis of the tubular portions 200 and 210, and on the tilt of the oblique section of the exhaust orifice 212.
Naturally, in order to satisfy local and specific requirements, a person skilled in the art may apply to the solution described above many logical and/or physical modifications and alterations. In particular, although the present invention has been described with a certain degree of detail with reference to preferred embodiments thereof, it should be understood that various omissions, substitutions and changes in the form and details as well as other embodiments are possible; moreover, it is expressly intended that specific elements and/or method steps described in connection with any disclosed embodiment of the invention may be incorporated in any other embodiment as a matter of general design choice.
For example, the predetermined value of water pressure can be chosen according to design requirements and economic and/or practical assessments, even considering the system wherein the valve is intended to be inserted.
The door 220, of course, may occupy various intermediate positions during the operative opening configuration of the valve 130, depending on the flow of water present within the drain pipe (and therefore the pressure exerted by it on the door 220).
The valve body 203 may be made in one piece, such as plastic moulding, or it may be formed by separate parts that can be assembled, for example the tubular portions 200, 210 may be manufactured separately and assembled a posteriori; in this way, by providing for example an adjustable-curve joint, it is possible to connect the two tubular portions by adjusting the respective angle even after the production. This would allow using a few production equipments for making different configurations (responding to corresponding requirements) of the drain valve 130.
The door 220 can be hinged in any way, provided that the door is allowed to rotate on its side; it is also possible to provide that the hinging support allows a slight shift of the door 220 along the plane of the section of the exhaust orifice 212, so as to give greater mobility to the door 220.
The door 220, the tubular portions 200, 210 and the support appendix 215 can be also made of non-plastic materials, and/or different materials different from each other; for example, the door 220 can be made of aluminium, or composite material including metal and/or very hard plastics. In addition, the door 220 may have a complex structure, including, for example, membranes appropriately positioned (for example, with a supporting function to the door in applications wherein the requirement of preventing the gas passage is very strict).
The fixing appendix 205 can be of different type, and may include equivalent elements, depending on the location and fixing orientation of the valve. For example, it is possible to use fixing screws, or highly adhesives components, instead of the hook elements 207.
Finally, it is possible to have a drain pipe 120 whose end portion is folded and shaped in the way described above in relation to the valve body 203, with the door 220 hinged directly to the drain pipe 120 at its exhaust orifice.
Moreover, the described solution may be used both in refrigeration apparatus, such as refrigerators (and the like), and in conditioning equipment (e.g., air conditioners). In fact, although in the present description explicit reference has been made to refrigerators employing no-frost systems, the present invention may be applied generally to cooling apparatus wherein it is necessary to regulate a flow of fluids and prevent a backflow thereof.
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