The present invention generally relates to the field of household appliances. More specifically, the present invention relates to laundry washing machines and laundry washing/drying machines, both for domestic and professional use.

Laundry washing and washing/drying machines (hereinafter simply referred to as

"washing machines") are household appliances designed to wash laundry and typically comprise a washing tub housing a rotatable perforated drum in which the laundry to be washed can be loaded/unloaded.

In order to carry out washing operations on laundry loaded into the drum, washing liquid (e.g. , water, water mixed with washing products and/or water mixed with rinsing products) is introduced - through an inlet line - in the washing tub of the washing machine during a washing liquid loading phase. Being the drum perforated, the washing liquid penetrates thereinto, soaking the laundry.

Then, a washing phase is started in which the drum is rotated, so that the laundry loaded into the drum is washed thanks to the chemical reactions exerted by the washing liquid, supported by the tumbling action caused by the rotation of the drum.

At the end of the washing phase, the washing liquid (which is at this point mixed with dirt particles coming from the laundry) is removed from the washing tub for allowing the carrying out of rinsing and/or spin-drying operations on the laundry.

For this purpose, the washing machine is provided with a discharge system adapted to selectively drain the washing liquid from the washing tub. The discharge system comprises a discharge duct for receiving the washing liquid to be discharged. The discharge duct is fluidly coupled with the washing tub through a discharge hole provided at the bottom of the washing tub. A drain pump, usually positioned downstream the discharge duct, is operable to cause the washing liquid located into the discharge duct to be discharged through a drain hose adapted to be connected to the water drain network system. In some types of know washing machines, a valve is provided for selectively opening/closing the discharge hole in order to selectively allow/block washing liquid to flow between the washing tub and the discharge duct.

On this regard, valves of the floating type - hereinafter, "floating valves" - are known, comprising a floating closure member arranged in the discharge duct and adapted to open/close the discharge hole based on the amount of liquid located in the discharge duct. The floating closure member is buoyant in the washing liquid. As the level of liquid in the discharge duct increases, the floating closure member is pushed toward the washing tub. The floating valve further comprises a valve seat, for example a gasket member, provided with an opening for allowing liquid to pass from the washing tub to the discharge duct when the floating closure member is spaced apart from the valve seat. When the floating closure member abuts against the valve seat because of the pressure exerted by the liquid located in the discharge duct, the opening of the valve seat is closed by the floating closure member, preventing further exchanges of fluids between the washing tub and the discharge duct.

Before performing the washing liquid loading phase, the floating valve should be closed, in such a way to avoid that the clean washing liquid that is supplied in the subsequent phase is wasted in the discharge duct without being participated in the washing process, to avoid that dirt residual accumulated in the discharge duct mixes with the supplied washing liquid, as well as to thermally insulate the washing tub from the discharge duct.

For this purpose, a valve closing phase may be carried out before starting the actual washing liquid loading phase. During this valve closing phase, firstly, a prefixed amount of water is introduced in the washing tub through the inlet line; since when the discharge duct is empty the floating valve is still open, this prefixed amount of water flows through the valve into the discharge duct, forming a corresponding water column in the drain hose. The drain pump is then turned on impulsively (for example, it is activated for one second) for decreasing the level of water in the discharge duct and correspondingly increasing the level of the water column contained in the drain hose. Once the drain pump is turned off, water flows back from the drain hose to the discharge duct under the action of the gravity force in order to try to re-establish the condition reached prior to the activation of the drain pump, exerting a pressure which causes the floating closure member to abut against the valve seat and close its opening.

However, during the flow back of the water, air sucked by the drain pump from the washing tub during the impulsive activation of the pump concentrates in the portion of the discharge duct located between the lower side of the valve seat and the floating closure member. Such amount of air elastically opposes to the floating valve closure, disadvantageously reducing the leak-proofing thereof.

International patent application No.WO2009/083365 discloses a washing machine in which the valve or the hose have at least some portions thereof surrounding the volume wherein air is concentrated that is produced of a gas permeable water impermeable material, allowing the air to be discharged during the valve closure.

The Applicant has found that a solution of this type it is not efficient in terms of production costs, since some of the components of the washing machine should be implemented with specific gas permeable water impermeable materials, which are very costly. Moreover, such materials are particularly prone to wear, and require an improved maintenance.

In a further known solution, an air passage, e.g. , a hole, is provided, which connects the discharge duct with the washing tub for allowing air trapped in the discharge duct to be discharged in the washing tub during the valve closure, increasing the leak- proofing of the floating valve, without having to employ materials specifically designed to be gas permeable and water impermeable. In order to minimize the amount of washing liquid that might pass into the discharge duct during the washing operations through such an air passage, the latter is advantageously designed to have a small cross section.

However, when such an air passage is present, a certain amount, even if small, of the washing liquid present in the discharge duct may flow through the air passage, reaching the washing tub. For example, during the above described valve closing phase, after the drain pump is turned off, a certain amount of the water, pushed by the gravity force from the drain hose towards the valve seat may enter the air passage and gush into the water tub, possibly reaching the lateral wall of the drum and, via the holes provided in the latter, the laundry contained therein. This may disadvantageously soil the laundry, since liquid coming from the discharge duct may be dirty, because of dirt accumulated in the discharge duct after washings and/or because of the presence of foreign bodies settled in the discharge duct, such as coins, which may release rust particles in the water.

Applicant has handled the problem of devising a not-expensive solution which allows reducing the drawbacks caused by the abovementioned concentration of air in the discharge duct, avoiding at the same time that the laundry contained in the drum is soiled. In very general terms, the solution according to one or more embodiments of the invention is based on the idea of providing an intercepting member arranged to prevent a liquid flow exiting the air passage connecting the discharge duct with the washing tub from hitting the washing drum of a washing machine.

In this way, it is possible preventing that possible dirty liquid contacts the drum

(reducing therefore the risk that this liquid soils the laundry contained therein), allowing at the same time the air trapped in the discharge duct to be discharged in the washing tub during the closure of the valve which selectively allows/blocks the washing liquid to flow between the washing tub and the discharge duct.

In particular, one aspect of the present invention proposes a washing machine. The washing machine comprises a washing tub in which washing liquid may be loaded, a perforated drum rotatably accommodated in the washing tub for containing laundry to be washed, and a discharge system fluidly connected to the washing tub and adapted to selectively discharge washing liquid from the washing tub. The washing machine further comprises a valve, placed between the washing tub and the discharge system. The valve comprises a valve seat through which liquid can pass from the washing tub to the discharge system. The valve further comprises a closure member movable with respect to the valve seat from a closing position, in which said closure member abuts against the valve seat, impeding the flow of washing liquid from the washing tub to the discharge system, to an open position in which said closure member is at least partially spaced apart from the valve seat, allowing the flow of washing liquid from the washing tub to the discharge system. The washing machine further comprises an air passage fluidly connecting said discharge system and said washing tub for allowing the passage of at least air from the discharge system to the washing tub. The washing machine further comprises an intercepting member arranged to prevent a liquid flow exiting said air passage from hitting said drum.

Preferred features of the present invention are set in the dependent claims.

According to an embodiment of the present invention, said intercepting member is arranged in such a way to intercept a liquid flow exiting said air passage and directed toward the drum.

According to an embodiment of the present invention, the intercepting member is arranged to deflect away from the drum a liquid flow exiting said air passage.

According to an embodiment of the present invention, the intercepting member comprises a deflecting surface displaced transversally, preferably perpendicularly, to the longitudinal axis of said air passage.

According to an embodiment of the present invention, said air passage comprises an air pipe extending substantially parallel to the longitudinal axis of the discharge hole.

According to an embodiment of the present invention, said air pipe comprises a first air pipe having a top end with a first opening located in the washing tub interior and having a bottom end with a second opening facing the discharge system.

According to an embodiment of the present invention, the intercepting member is placed in proximity of the top end of the first air pipe.

According to an embodiment of the present invention, said first air pipe is integral with the washing tube.

According to an embodiment of the present invention, the valve seat includes a hole facing said second opening.

According to an embodiment of the present invention, said air passage comprises a second air pipe integral with the valve seat and coaxially fitted inside the first air pipe.

According to an embodiment of the present invention, said first air pipe is integral with the valve seat.

According to an embodiment of the present invention, said air passage comprises a hole located on said valve seat.

According to an embodiment of the present invention, the intercepting member is integral with the washing tub.

These, and others, features and advantages of the solution according to the present invention will be better understood by reading the following detailed description of some embodiments thereof, provided merely by way of exemplary and non-limitative examples, to be read in conjunction with the attached drawings, wherein:

Figure 1 is a schematic front view of a washing machine in which embodiments of the present invention may be implemented;

Figure 2 is a partially exploded view of a washing tub of the washing machine of

Figure 1 ; Figure 3 is a partially exploded view of a portion of a discharge system of the washing machine of Figure 1 ;

Figure 4 is a simplified cross-sectional view of a drum-washing tub-discharge system assembly according to an embodiment of the present invention, and

Figure 5 is a simplified cross-sectional view of a drum-washing tub-discharge system assembly according to another embodiment of the present invention.

With reference to the drawings, Figure 1 is a front view of a washing machine 100 in which embodiments of the present invention may be implemented.

The washing machine 100 is a machine for treating (washing, or washing/drying) laundry of the front- loading type. Anyway, it should be apparent from the following description that the inventions can be applied, without any substantial modification, to a washing machine of the top-loading type.

In the example at issue, the washing machine 100 advantageously comprises a preferably substantially parallelepiped-shaped casing 105 that encloses a washing tub 107 wherein laundry is treated, along with any other components of the washing machine 100 necessary for the operation (e.g. , hydraulic, electronic and electromechanical apparatuses known in the art and, therefore, not herein described for sake of conciseness).

The washing tub 107 houses a rotatable perforated drum 1 10, preferably substantially cylindrical-shaped, in which laundry 112 to be washed can be loaded.

In order to allow a user to access the washing tub and the inside of the drum 110

(for loading/unloading the laundry), a loading/unloading opening closable by a door, not illustrated, is advantageously provided, preferably on a front side of the washing machine 100.

A water supply system 120 and a detergent supply system 122 are arranged preferably in the upper part of the washing machine 100 for supplying washing liquid into the washing tub 107. The detergent supply system 122 advantageously comprises a removable drawer 123 provided with compartments suited to be filled with washing and/or rinsing products.

Water flowing through the water supply system 120 is advantageously supplied into the washing tub 107 by making it flow through the drawer 123 and through an inlet line 125 in fluidly communication with the washing tub 107. The water supply system 120 further comprises a main pipe 130 fluidly connecting the drawer 123 to an external water supply line 135, preferably by means of a controlled input supply valve 140.

Washing liquid which reaches the washing tub 107 may selectively contain one of the products contained in the compartments of the drawer 123, or may be clean water (i.e. , which does not contain any product), depending on the washing program which is actually performed. For example, during a washing phase, the washing liquid conveyed into the washing tub 107 is made to contain one of the products contained in the compartments of the drawer 123, while in other phases, for example during the rinsing phase, the washing liquid is only water. Alternative arrangements may be provided, for example with a separate water inlet line adapted to supply exclusively clean water into the washing tub 107.

Figure 2 is a partially exploded view of an exemplary washing tub 107. The washing tub 107 has preferably a substantially cylindrical shape and is made of waterproof material which is also able to withstand operating temperatures and chemicals reactions promoted by washing liquids during the washing machine operation, such as a plastic polymer. The washing tub 107 comprises a front semi-shell section 205a and a rear semi-shell section 205b, each having preferably substantially the shape of a hollow half- cylinder. The front semi-shell section 205a and the rear semi-shell section 205b are coupled to each other (e.g. , by means of pins or bolts, or welding) to enclose therebetween the drum 110.

The washing machine 100 is provided with a discharge system 300 adapted to selectively dispose washing liquid from the washing tub 107, e.g., after a washing phase is finished.

Figure 3 is a partially exploded view of a portion of an exemplary discharge system 300.

Making reference to Figures 1-3, the discharge system 300 comprises a discharge duct 310 arranged to be coupled with the washing tub 107 for receiving the washing liquid to be discharged. In the example illustrated in Figure 3, the discharge duct 310 is a manifold made of a rigid material, such as plastic. Anyway, in a further advantageous embodiment, the discharge duct 310 may be a flexible hose, for example made in a flexible material, such as rubber. The discharge duct 310 is arranged to be selectively in fluid communication with the washing tub 107, preferably through a discharge hole 210 provided at the bottom of the washing tub 107. In the example illustrated in Figure 2, the discharge hole 210 is provided at a bottom portion of the front semi-shell section 205a. Naturally, similar considerations apply with different configurations, such as for example if the discharge hole 210 is located at the rear semi-shell section 205b, or if the discharge hole 210 is located partially at the at the front semi-shell section 205a and partially at the rear semi-shell section 205b.

The way the discharge duct 310 and the washing tub 107 are coupled one to another may depend on various factors, such as the materials and the shapes thereof. In the example at issue, the washing tub 107 advantageously includes a drain collar - identified in Figure 2 with the reference 215 - surrounding the discharge hole 210 and protruding downward from the front semi-shell section 205 a, and the discharge duct 310 comprises a discharge duct input opening 315 surrounded by a sleeve 317 adapted to be fitted around the drain collar 215.

The discharge system 300 advantageously further comprises a drain pump 320, e.g. , positioned downstream the discharge duct 310, which is operable to cause liquid located into the discharge duct 310 to be discharged through a drain hose 322 (see Figure 1) adapted to be connected to a water drain network system (not illustrated).

The discharge system 300 further comprises a valve 330 advantageously located at the discharge duct input opening 315 for selectively opening/closing the discharge duct input opening 315, and thus the discharge hole 210 as well, in order to selectively allow/block liquid to flow between the washing tub and 107 the discharge duct 310.

The valve 330 is preferably a floating-type valve, comprising a floating closure member 340 arranged in the discharge duct 310 in such a way to allow/prevent the passage of liquid from the tub 107 to the discharge duct 310, preferably based on the amount of liquid located in the discharge duct 310. The floating closure member 340 is advantageously made of a material and/or has a shape (for example including hollow cavities) that makes the floating closure member 340 to float in the washing liquid. As the level of liquid in the discharge duct 310 increases, the floating closure member 340 goes up the discharge duct 310, being pushed toward the washing tub 107 interior by the pressure exerted by the column of liquid located in the drain hose 322. The valve 330 further comprises a valve seat 350 adapted to be arranged at the discharge hole 210 of the washing tub 107. The valve seat 350 is preferably in the form of a, e.g. , flexible, gasket, for example fitted on the sleeve 317 wherein the discharge duct input opening 315 of the discharge duct 310 is located. Similar considerations apply if the valve seat 350 is fitted on the drain collar 215 surrounding the discharge hole 210. The valve seat 350 is advantageously provided with a seat opening 360 - which opportunely faces the discharge hole 210 and the discharge duct input opening 315 - for allowing liquid to pass from the washing tub 107 to the discharge duct 310 when the floating closure member 340 is spaced apart from the valve seat 350. When the floating closure member 340 abuts the valve seat 350 because of the pressure exerted by the column of water located in the drain hose 322, the valve seat opening 360 is closed by the floating closure member 340, preventing further exchanges of fluids between the washing tub 107 and the discharge duct 310. The floating closure member 340 is advantageously shaped in such a way that its upper portion matches the valve seat opening 360 when abutting against the valve seat 350.

In order to reduce the amount of air which may concentrate in the upper portion of the discharge duct 310 between the lower side of the valve seat 350 and the floating closure member 340, and which may elastically oppose to the closure of the valve 330, an air passage coupling the discharge duct 310 with the washing tub 107 is advantageously provided. The presence of such air passage allows air trapped in the discharge duct 310 to be discharged in the washing tub 107 during the closure of the valve. According to an embodiment of the present invention, an intercepting member is provided, arranged in such a way to avoid a liquid flow exiting the air passage (e.g. coming from the discharge system 300 through the air passage and directed toward the drum 110) hits the drum 110 (and, via the holes provided in the latter, the laundry 112 contained therein). According to an embodiment of the present invention, this is obtained by arranging the intercepting member in such a way to intercept said liquid flow.

Figure 4 is a simplified cross-sectional view of the drum-washing tub-discharge system assembly according to an embodiment of the present invention.

According to this embodiment of the invention, the air passage connecting the discharge duct 310 with the washing tub 107 comprises an air pipe 410, extending along a direction B substantially parallel to the axis of the discharge hole 210. The air pipe 410 has a top end 412 with an opening 415 located in the washing tub 107 interior, and a bottom end 417 with an opening 420 facing the discharge duct 310 interior. In the advantageous embodiment of Fig. 4, the opening 420 faces a hole 425 provided on the valve seat 350, for example at a border portion thereof. In this way, air located within the discharge duct 310 may advantageously pass through the hole 425, go up the air pipe 410, and then reach the washing tub 107 interior through the opening 415. According to this embodiment of the present invention, an intercepting member 430 is provided in correspondence to the top end 412 of the air pipe 410, so as to intercept liquid flows coming from the discharge duct 310 through the air passage and directed toward the drum 110.

According to an embodiment of the present invention, the intercepting member 430 comprises a roof or a shield or a deflector element having a deflector surface 430a which extends transversally, preferably substantially perpendicularly, to the direction B. Advantageously, the presence of such roof or shield or deflector element avoids that washing products enter the air pipe 410 (because of gravity) and discharge into the discharge duct 310.

Other configurations are also contemplated, wherein the intercepting member 430 has different orientations, provided that said orientations allow the intercepting member 430 to intercept liquid flows coming from the discharge duct 310 and directed toward the drum 110. According to these embodiments of the invention, the intercepting member 430 is arranged in such a way that if washing liquid, water, and/or foam located in the discharge duct 310 passes through the air passage (in this embodiment of the invention, goes up the air pipe 410), instead of reaching the drum 110 (and dirtying the laundry contained therein), this washing liquid, water, and/or foam is advantageously deflected away from the drum, e.g. , toward the bottom of the washing tub 107.

According to another embodiment of the present invention, instead of comprising a roof or a shield or a deflector element, the intercepting member 430 may advantageously comprise one or more protruding elements shaped and positioned in such a way to "break" the liquid flow coming from the air passage into a plurality of smaller flows which are not capable of reaching the drum 110. In order to minimize the amount of washing liquid that might pass from the washing tub 107 into the discharge duct 310 during the washing operations, the openings 415, 420 and the hole 425 have sufficiently small sizes.

Advantageously, as illustrated in Figure 4, both the air pipe 410 and the intercepting member 430 are integral to (i.e. made in a single-piece construction with) the washing tub 107. However, similar considerations apply if the air pipe 410 and/or the intercepting member 430 are separated pieces attached to the washing tub 107, for example through snap-fit engagements, pins, welding, or glue.

According to another embodiment of the present invention, instead of having a simple hole (i.e. , the hole 425 of Figure 4), the valve seat 350 directly comprises a respective air pipe, which extends parallel to the air pipe 410 (e.g. , substantially parallel to the direction B). For example, in the embodiment of the invention illustrated in Figure 5, the valve seat 350 is provided with an air pipe 510 (e.g. , integral to the valve seat 350) adapted to be coaxially fitted inside the air pipe 410. In this case, the resulting air passage connecting the discharge duct 310 with the washing tub 107 is more reliable, being less prone to blockings due to possible misalignments between the valve seat 350 and the washing tub 107. An isometric view of the air pipe 510 located on the valve seat 350 according to an embodiment of the present invention is also visible in Figure 3.

According to another advantageous embodiment of the present invention (not illustrated in enclosed figures), the washing tub 107 does not include the air pipe 410, and the air passage connecting the discharge duct 310 with the washing tub 107 comprises instead the air pipe 510, arranged in such a way to directly face the internal of the tub or to face or to pass through a hole provided on the washing tub 107. In this case, the intercepting member adapted to intercept liquid flows coming from the discharge duct 310 and directed toward the drum 1 10 may be directly arranged on the valve seat 350 (e.g. , integral to the air pipe 510) or arranged on the washing tub 107, (e.g., protruding from a wall thereof).

According to a further embodiment of the present invention (not illustrated in the figures), the air passage connecting the discharge duct 310 with the washing tub 107 does not include any dedicated air pipe, and comprises instead a simple hole provided on the valve seat 350, which puts in communication the internal of the tub and the discharge duct 310.

In a further advantageous embodiment, the air passage connecting the discharge duct 310 with the washing tub 107 comprises a hole provided on the valve seat 350, facing a further hole provided in the washing tub 107. In this case as well, the intercepting member may be directly arranged on the valve seat 350 (e.g. , protruding therefrom) or arranged on the washing tub 107 (e.g. , protruding from a wall thereof).

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.

For example, although the embodiments of the invention described above make reference to a single air passage in parallel to the discharge hole, similar considerations apply in case more than one air passages connect the discharge duct with the washing tub.

Furthermore, even if in the description reference has been mainly made to an air passage crossing the valve seat of the floating valve, the concepts of the present invention apply as well in case the air passage connecting the discharge duct with the washing tub is provided on a portion of the discharge duct itself, for example provided with a respective hole or a respective air pipe overlapped with a corresponding hole (or coaxially fitted in a corresponding air pipe) provided in the washing tub.

Moreover, even if in some of the described embodiments reference has been made to an air passage comprising an air pipe extending substantially parallel to the axis of the discharge hole of the washing tub, similar considerations apply if the air pipe has a different orientation, and/or includes bends.