The invention relates to a washing machine (the expression "washing machine" including both "simple" washing machines, i.e. washing machines which can only wash and rinse laundry, and washing-drying machines, i.e. washing machines which can also dry laundry, both of the front-loading or top-loading type) with a draining circuit comprising a valve element adapted to selectively open and close the passage of liquid from a tub to the draining circuit, and a filter element for impeding that foreign bodies such as coins or buttons escaping the laundry could reach the draining pump.

EP1204792 discloses a washing machine, wherein an inlet of a draining circuit is fluidly connected to a sump. A valve element is arranged between the sump and the inlet of the draining circuit. The valve element shuts off the sump from the draining circuit during a washing cycle by using a valve seat and a ball as closing element. The ball is freely movable within a draining section of the draining circuit.

By using a valve element of the above kind, water within the draining circuit needs not be heated during a heating phase of a washing cycle of the washing machine, whereby the energy consumption of the washing machine is reduced. Assembling of the draining circuit in a way that guarantees proper operation of the valve and long-term functionality of the closing state of the valve element may be a problem, as such a valve element however is a component in danger of failure, e.g. because of clogging. As such it needs servicing. Servicing however may be complicated by valve element design and mounting location and in the consequence cost intensive.

EP2503050 tries to solve above problem by providing a washing machine comprising a tub with a sump and a draining circuit, wherein the sump is fluidly connected to the draining circuit. A filter element is provided, which is removably positionable in the sump, e.g. which can be removed from the sump by a user, e.g. for cleaning or replacement, and can be (re)inserted into the sump thereafter. By inserting the filter element in the sump, preferably upstream the draining circuit, foreign objects and fluff are effectively filtered out of the liquid drained from the tub. In consequence, no or a reduced amount of foreign objects enter the draining circuit of the washing machine. The sump is preferably formed integrally with the tub, such that no additional mounting or assembly step is necessary for mounting the sump at the tub. The washing machine may preferably comprise a chamber for at least a portion of a draining pump, wherein the chamber is preferably integrally formed with the sump and the tub, such that fewer assembling steps and less assembly time for assembling the washing machine are required. The washing machine disclosed in EP2503050 also comprises a valve element for selectively obstructing (or closing) a passage of liquid from the tub to the draining circuit. As such, the valve element is preferably arranged downstream the tub and upstream the draining circuit. The valve element is adapted to seal or close the tub from the draining circuit, preferably in particular during a heating phase of a washing cycle of the washing machine. By blocking the fluid connection to the draining circuit when the valve element is in its closed position, water within the draining circuit is not heated and the energy consumption of the washing machine is reduced. For enhancing the serviceability of the washing machine with respect to the valve element, e.g. for easy handling thereof, the filter element comprises the valve element. By providing a filter element comprising the valve element, the valve element can for example be removed from the sump or be (re)inserted together with the filter element such that easy handling of the valve element is provided. As a consequence, serviceability of the washing machine is improved.

EP2746448 discloses a laundry treatment appliance. The laundry treatment appliance comprises a rigid tub for containing laundry treatment liquids, the tub comprising a tub outlet for draining the treatment liquids therefrom, a manifold comprising a manifold inlet coupled with the tub outlet for receiving said treatment liquids, and a gasket arranged between said manifold inlet and said tub outlet for sealingly coupling thereof. The laundry treatment appliance further comprises a floating valve, pivotally hinged to said gasket, adapted to swing between a closed position wherein the floating valve abuts a valve seat associated with the gasket thereby impeding the passage of the treatment liquids from said tub to said manifold, and an opened position wherein the floating valve is at least partially spaced from said valve seat thereby allowing the treatment liquids to pass from said tub to said manifold. Said floating valve and said valve seat have different rigidity.

Applicant has found that the above-described solutions are noisy. Indeed, in the solutions disclosed in EP1204792 and in EP2503050 the valve element is allowed to move within a rigid body, i.e. the sump and the filter element, respectively. Thus, with respect to previous solutions providing a valve element freely movable within a non-rigid sleeve connecting the sump and the draining circuit to each other, the solutions disclosed in EP1204792 and in EP2503050 represent a worsening in terms of noise perceived by the user.

Applicant has found that the above-described solutions also cause limited floating valve movement capabilities. Indeed, foreign bodies accumulating in the filter element may interfere with, and impair, valve element movement, thus negatively affecting both valve element ascending movement (and hence mechanical and thermal insulation between the tub and the draining circuit) as well as valve element descending movement (and hence quick draining of the treatment liquids from the tub). Moreover, noise and valve element movement capabilities issues are exacerbated by relatively large and/or frequent mechanical vibrations produced by the washing machine during operation thereof.

Valve element movement capabilities issues may also cause more serious drawbacks, especially in solutions, such as that disclosed in EP2503050, wherein the valve element is operated within a meshed filter element. Indeed, being substantially freely movable within the filter element, the valve element, especially during its ascending movement, may experience friction with, until getting jammed into, the filter element mesh, so that the valve element may be not allowed to complete its ascending movement.

Applicant has faced the problem of devising a satisfactory solution able to overcome the above-discussed, as well as other, drawbacks.

In particular, one or more aspects of the solution according to specific embodiments of the invention are set out in the independent claims, with advantageous features of the same solution that are indicated in the dependent claims (with any advantageous feature provided with reference to a specific aspect of the solution according to an embodiment of the invention that applies mutatis mutandis to any other aspect thereof).

An aspect of the solution according to one or more embodiments of the invention relates to a laundry washing machine. The laundry washing machine comprises a tub for containing treatment liquids, the tub comprising a sump fluidly connected or connectable to a draining circuit of the washing machine, and a valve/filter assembly adapted to be removably positioned in a filter seat provided in the sump for intercepting and filtering the treatment liquids while passing from said tub to said draining circuit. Said valve/filter assembly comprises:

• a receptacle having an inlet for the access of the treatment liquids coming from the tub, and a filtering surface through which said treatment liquids coming from the tub can pass to said draining circuit, said filtering surface being adapted to retain within said receptacle foreign bodies entering said inlet,
• a valve seat fixed or fixable to an open end of said receptacle, and
• a valve element pivotally hinged to said valve seat so as to swing within the receptacle, when said valve seat is fixed to said receptacle, between a closed position in which the valve element abuts the valve seat, thereby preventing passage of liquid from said tub to said draining circuit, and an opened position in which the valve element is at least partially spaced from said valve seat, thereby allowing liquid to pass from said tub to said draining circuit trough said filtering surface of said receptacle.

According to an advantageous embodiment of the invention, the valve/filter assembly comprises a gasket element arranged in such a way to provide a watertight connection between said valve element and said valve seat in said closed position of said valve element.

According to an advantageous embodiment of the invention, said valve element comprises a rigid core on which said gasket element is over-injected.

According to an advantageous embodiment of the invention, said valve seat comprises a rigid frame on which said gasket element is over-injected.

According to an advantageous embodiment of the invention, said valve element is pivotally hinged to said valve seat by a resilient connection comprising said gasket element, a layer of resilient material at least partially over injected on a rigid core of said valve element, and at least one flexible connecting element made in a single piece construction with said gasket element and said layer of resilient material.

According to an advantageous embodiment of the invention, said valve element is made of a resilient material and is pivotally hinged to said valve seat by a resilient connection comprising said valve element, said gasket element, and at least one flexible connecting element made in a single piece construction with said gasket element and said valve element.

According to an advantageous embodiment of the invention, the valve seat further comprises at least one protruding member adapted to be removably associated with at least one corresponding housing of said valve element for pivotally hinging said valve element to said valve seat in a removable manner.

According to an advantageous embodiment of the invention, the at least one protruding member is made in a single piece construction with the gasket element.

According to an advantageous embodiment of the invention, said valve/filter assembly comprises at least one fixing element adapted to removably fix both said receptacle to said valve seat and said valve/filter assembly to said filter seat.

According to an advantageous embodiment of the invention, the at least one fixing element is mechanically coupled to said receptacle and is elastically deformable, elastic deformation of the at least one fixing element allowing insertion and snap-fit fixation of said receptacle in said filter seat.

According to an advantageous embodiment of the invention, the valve seat further comprises at least one slot for allowing passage of the at least one fixing element therethrough during fixation of said valve seat to said receptacle.

According to an advantageous embodiment of the invention, at least part of the valve seat is adapted to rest, upon positioning said valve/filter assembly in said filter seat, on an inner flange provided in the sump and delimiting the inlet of said filter seat. Said valve/filter assembly is positioned in said filter seat, and said at least one fixing element engages said inner flange for fixing the valve/filter assembly in said filter seat.

According to an advantageous embodiment of the invention, said valve/filter assembly comprises a locking element adapted to take a locking position wherein it prevents removal of the fixation of said receptacle to said a valve seat and of the fixation of said valve/filter assembly to said filter seat.

According to an advantageous embodiment of the invention, the locking element comprises at least one cap member removably fixable to said valve seat.

According to an advantageous embodiment of the invention, the at least one cap member, in said locking position, covers said at least one slot and the at least one fixing element therethrough.

According to an advantageous embodiment of the invention, said valve element is provided with at least one wall that extends from a side of said valve element facing, in operation, the bottom of said receptacle, said at least one wall delimiting at least one air capturing chamber adapted to capture air thereby enhancing floating of said valve element.

Applicant has also found that the known solutions (featuring both valve and filter elements) are difficult to mount, especially as far as mounting of the valve element on the filter element and mounting of the filter element into the respective seat are concerned, and that known mounting solutions are unreliable (thus requiring frequent servicing) and inconvenient to practice (thus making servicing difficult).

Thus, in order to overcome these, as well as other drawbacks, another aspect of the invention relates to a washing machine comprising:

• a tub for containing treatment liquids, the tub comprising a sump fluidly connected or connectable to a draining circuit of the washing machine, and
• a valve/filter assembly adapted to be removably positioned in a filter seat provided in the sump for intercepting and filtering the treatment liquids while passing from said tub to said draining circuit, said valve/filter assembly comprising:
  • a filter element,
  • a valve seat fixed or fixable to an open end of said filter element,
  • a valve element pivotally hinged to said valve seat so as to swing within the filter element between closed and opened positions preventing and allowing, respectively, passage of the treatment liquids from said tub to said draining circuit, and
  • at least one elastically deformable fixing element mechanically coupled to said filter element, said at least one fixing element being allowed to pass, when a deforming force is applied thereto, through at least one slot of the valve seat and to engage said valve seat when said deforming force is released, and said valve/filter assembly being allowed to pass, when a deforming force is applied to said at least one fixing element, into said filter seat and to engage said filter seat when said deforming force is released.

These and other features and advantages of the solution according to one or more embodiments of the invention will be best understood with reference to the following detailed description, given purely by way of a non-restrictive indication, to be read in conjunction with the accompanying drawings (wherein corresponding elements are denoted with equal or similar references, and their explanation is not repeated for the sake of exposition brevity). In this respect, it is expressly understood that the figures are not necessarily drawn to scale (with some details that may be exaggerated and/or simplified) and that, unless otherwise indicated, they are simply used to conceptually illustrate the described structures and procedures. In particular:

• Figure 1 shows a sectional side view of a washing machine according to an embodiment of the invention;
• Figure 2A shows an exploded perspective side view of a valve/filter assembly according to an embodiment of the invention;
• Figures 2B and 2C show front and sectional side views, respectively, of the valve/filter assembly in a fitted condition, according to an embodiment of the invention;
• Figure 2D shows sectional views of a floating valve of the valve/filter assembly in opened and closed positions, according to an embodiment of the invention;
• Figure 2E shows perspective assembled and exploded bottom views of a floating valve/valve seat group of the valve/filter assembly, according an embodiment of the invention;
• Figure 2F shows perspective side views of the valve/filter assembly in full-closed and full-opened conditions, according to an embodiment of the invention, and
• Figure 2G shows side and perspective side views of a valve seat/locking element of the valve/filter assembly in engaged and disengaged conditions, according to an embodiment of the invention.

With reference to the drawings, Figure 1 shows a sectional side view of a washing machine 100, for example for domestic use, according to an embodiment of the invention. The washing machine may be a "simple" washing machine, i.e. a washing machine that can only wash and rinse laundry, or a washing-drying machine, i.e. a washing machine that can also dry laundry. As exemplary illustrated, the washing machine 100 is of the front-loading type (anyway, it should be apparent from the following description that washing machines of the top-loading type may also benefit from the invention).

The washing machine 100 preferably comprises a substantially parallepiped-shaped cabinet 105, which is apt to contain (e.g., hydraulic, electronic and/or electromechanical) components for allowing washing machine operation - only the relevant ones for understanding the invention being discussed in the following.

In this respect, the washing machine 100 comprises, within the cabinet 105, a rotating, preferably perforated, drum 110 (e.g., substantially cylindrical-shaped) configured to rotate for tumbling laundry loaded therein.

The drum 110 is enclosed within a washing tub 115, preferably hollow-cylinder shaped, which is adapted to enclose the drum 110 and to contain treatment liquids (e.g., washing water, detergent-water solutions, or rinsing water) for laundry treatment. The tub 115 comprises, e.g. at a bottom thereof, a sump 120 for canalizing the treating liquids thereinto (and allowing them to be drained, as discussed herebelow).

The sump 120 is fluidly connected or connectable to a draining circuit 125 of the washing machine 100, which is adapted to drain the treatment liquids (coming from the tub 115, through the sump 120) to the sewer network (not shown) - or to a treatment liquids re-circulating circuit of the washing machine 100 (not shown).

The draining circuit 125 preferably comprises a motor driven pump 130, preferably arranged downstream the sump 120, for promoting the draining of the treatment liquids, and a draining hose 135, preferably provided downstream the pump 130, for draining the treatment liquids into the sewer network (and/or to the treatment liquids re-circulating circuit, when provided). The drain hose 135 advantageously comprises at least a substantially vertical part 135a extending at least partially at a height higher than the pump 130.

Advantageously, an appliance door 140 is provided (e.g., at a front panel of the cabinet 105, in the illustrated example) for accessing the drum 110.

According to the proposed invention, a valve/filter assembly 145 adapted to be removably positioned/fitted in the sump 120 is provided for intercepting and filtering the treatment liquids while passing from the tub 115 to the draining circuit 125.

As shown in Figure 1 (and better detailed in the following), the valve/filter assembly 145 is adapted to be removably positioned/fitted in a filter seat 150 of the sump 120. Preferably, the filter seat 150 comprises a sump inner flange 150_F, e.g. horizontally extending from vertical side walls of the sump 120, and a seat opening (delimited by said sump inner flange 150_F) astride which the valve/filter assembly 145 is positioned.

Broadly speaking, as will be progressively explained in the following while discussing embodiments of the invention, the proposed valve/filter assembly 145 is configured to efficiently control (i.e., prevent or allow) passage of the treatment liquids (through an inlet thereof) from the tub 115 to the draining circuit 125 during washing machine 100 operation, while filtering the treatment liquids, when passage thereof is allowed, from possible foreign bodies and/or lint.

As illustrated in Figure 1, the washing machine 100 further comprises one or more lifters arranged within the drum 110 for turning laundry, such as the lifters 155,160. The lifter 160 is advantageously additionally adapted for easy removal and insertion of the valve/filter assembly 145 (e.g. for maintenance, replacement and/or other servicing operations). In this respect, the lifter 160 is preferably provided with a fixed, hollow lifter base 160_B arranged on (i.e., whose hollow matches) a drum opening 110_OP, and with an openable (as illustrated), or removable, lifter lid 160_L for selectively covering/uncovering the lifter base 160_B (and, hence, the hollow thereof and the drum opening 110_OP). Thus, in the considered example, access to the valve/filter assembly 145 is easily allowed by opening the appliance door 140, aligning the lifter 160 (and, hence, the drum opening 110_OP) to the sump 120, and lifting (or removing) the lifter lid 160_L.

Turning now to Figure 2A, it shows an exploded perspective side view of the valve/filter assembly 145 according to an embodiment of the invention. For the sake of description ease, such figure will be discussed together with Figures 2B-2G.

The valve/filter assembly 145 comprises a valve element (e.g., a floating valve) 205 for allowing/preventing passage of the treatment liquids from the tub 115 to the draining circuit 125 during washing machine 100 operation, and a filter element 210 for filtering foreign bodies and/or lint from the treatment liquids.

Advantageously, in order to ensure the closure of the floating valve 205, at the beginning of a washing phase, after filling the washing tub 115 with water, the pump 130 is activated for a short time interval long enough to allow some water to go up in the substantially vertical part 135a of the draining hose 135, but not long enough for allowing the spillage of this water from the draining hose 135, and then the pump 130 is deactivated; in this way the water column present in the substantially vertical part 135a of the draining hose 135 applies a pressure on the floating valve 205 in its closure direction, ensuring its closure.

The filter element 210 is preferably a basket, or meshed, filter element, namely it comprises a receptacle 210_R having an inlet 210_I for the access of the treatment liquids coming from the tub 115, and a filtering surface 210_FS through which said treatment liquids coming from the tub 115 can pass to said draining circuit 125, with such a filtering surface 210_FS that is adapted to retain within said receptacle 210_R foreign bodies entering the inlet 210_I.

The receptacle 210_R is preferably made of a material exhibiting both resilient deformation capabilities (by resilient deformation meaning that when forces causing deformation are no longer exerted, natural return to original shape takes place) and rigidity properties (hereinafter referred to as semi-rigid material for differentiating it from a rigid material having no, or negligible, resilient deformation capabilities, and from a resilient material having no, or negligible, rigidity properties), and preferably features a top open end being larger, along a longitudinal direction X, than the seat opening. Thus, engagement by frictional contact between the receptacle 210_R and the sump inner flange 150_F can be established (as discussed below).

The receptacle 210_R, preferably made of low-density polyethylene, polypropylene, polycarbonate and/or other similar plastics, preferably features, from the open end thereof to a bottom end thereof, a (e.g., rounded) progressively narrowing shaping, exception made for one ore more (e.g., two) projecting portions 210_P1,210_P2 (projecting along the longitudinal direction X). Preferably, the projecting portions 210_P1,210_P2 are made of a semi-rigid material, more preferably they are made of the same material as the receptacle 210_R, and even more preferably they are made in a single piece construction with it. As visible in Figures 2B and 2C, the projecting portions 210_P1,210_P2 that, thanks to resiliency thereof, deform to a certain extent upon passage through the seat opening, abut against the sump inner flange 150_F after such a passage has taken place, thus providing a clamping action and effectively preventing involuntary valve/filter assembly 145 unfitting from the filter seat 150 (e.g., due to water column push action).

The valve/filter assembly 145 also comprises a valve seat 215, preferably comprising a rigid (e.g., plastics such as high-density polyethylene, or metal) or semi-rigid frame 215_F, and fixed or fixable to the open end of the receptacle 210_R.

The valve seat 215 is preferably elongated ring-shaped (whose central hole advantageously defines the inlet of the valve/filter assembly 145 selectively obstructed by the floating valve 205, as discussed below), and is preferably adapted to be hingedly arranged/mounted on the open end of the receptacle 210_R.

The valve seat 215 is, in use, operatively associated with (preferably, mechanically coupled to) the floating valve 205, and floatably contained within the receptacle 210_R.

In this respect, the floating valve 205, which may either comprise a rigid or semi-rigid core 205_C onto which a layer of resilient material (not shown) is at least partially over injected, or which may be substantially (i.e., approximately) completely made of a rigid, semi-rigid or resilient material, is pivotally hinged to the valve seat 215 so as to swing relative thereto between closed and opened positions.

Hinging of the floating valve 205, as guiding it into a limited, guided rotational movement with respect to the valve seat 215, makes floating valve 205 movement capabilities substantially unaffected, or at least much less affected than prior art solutions, by both presence of foreign bodies unavoidably accumulating in the receptacle 210_R and mechanical vibrations unavoidably produced by washing machine operation. Moreover, hinging of the floating valve 205 avoids that the floating valve 205 experiences friction with, until getting jammed into, the receptacle 210_R mesh. Furthermore, absence (or at least strong reduction) of vibrations and/or frictions affecting the floating valve 205, provides noise reduction.

In the closed position of the floating valve (illustrated in the right drawing of Figure 2D), the floating valve 205, pushed by the water column present in the draining circuit 125 downstream the floating valve 205, abuts the valve seat 215 (thereby preventing passage of the treatment liquids from the tub 115 to the draining circuit 125). Preferably, a gasket element 220 is arranged in such a way to provide a watertight connection between the floating valve 205 and the valve seat 215 in the closed position. The gasket element 220 is preferably provided between (at least part of) a lower surface of the valve seat 215 facing (in use) the floating valve 205 and the receptacle 210_R, so that in the closed position the floating valve 205 abuts the valve seat 215 with at least partial interposition of the gasket element 220. In order to ensure good and firm adherence upon floating valve 205 closure (thus compensating manufacturing tolerances and ensuring hydraulic sealing), the gasket element 220 is preferably made of a resilient material, being for example made of rubber, silicone or another resilient polymer. Indeed, due to different rigidity/resiliency between the rigid/semi-rigid material which the floating valve 205 (e.g., the core 205_C thereof) is made of, and the resilient material which the gasket element 220 is made of, highly effective friction and adherence upon their contact is experienced.

According to an advantageous embodiment, the gasket element 220 is over-injected (at least partially) on the valve seat frame 215_F. Additionally or alternatively, the gasket element 220 and the layer of resilient material at least partially over injected on the floating valve core 205_C may be advantageously formed in a single piece construction. In a further advantageous embodiment, although not shown, a portion of the gasket element 220 is over-injected on the floating valve core 205_C and another portion of the gasket element 220 is over-injected on the valve seat frame 215_F (so as to have a distributed gasket element partially over-injected over and connecting the valve core 205_C and the valve seat frame 215_F).

Thanks to provision of the gasket element 220 between the floating valve 205 and the valve seat 215, noise reduction upon contact thereof is achieved, which further reduces overall noise of the washing machine 100.

In the opened position of the floating valve 205 (illustrated in the left drawing of Figure 2D), the floating valve 205, upon failing the push action thereon (e.g., due to water column discharge caused by pump 130 activation) is at least partially spaced from the valve seat 215, thereby allowing passage of the treatment liquids from the tub 115 to the draining circuit 125 through the filtering surface 210_FS of the receptacle 210_R. Thus, the treatment liquids allowed to pass when the floating valve 205 is in the opened position are then intercepted by filtering surface 210_FS of the receptacle 210_R, and hence filtered from foreign bodies and/or lint, before being drained into the draining circuit 125.

According to the exemplary considered embodiment, in order to achieve hinging of the floating valve 205 to the valve seat 215, the floating valve 205 preferably comprises one or more, e.g. two housings 205_H1,205_H2, whereas the valve seat 215 preferably comprises corresponding protruding members (preferably, two pegs) 220_P1,220_P1 each one adapted to be fitted into a corresponding housing 205_H1,205_H2.

Preferably, the pegs 220_P1,220_P1 are made of a resilient material, more preferably they are made of the same material as the gasket element 220, and even more preferably they are made in a single piece construction with it.

In a different advantageous embodiment, not illustrated, the pegs 220₁,220_P2 (or other flexible connecting elements) can be advantageously made in a single piece construction with both the gasket element 220 and a layer of resilient material at least partially over injected on the valve rigid core 205_C, so that the gasket element 220, the layer of resilient material, and the pegs 220_P1,220_P2 form a resilient connection for pivotally hinging the floating valve 205 to the valve seat 215.

In a further different advantageous embodiment, not illustrated, the floating valve 205 can be advantageously made of a resilient material, the floating valve 205, the gasket element 220, and the pegs 220_P1,220_P2 may be made in a single piece construction, so as to form, as a whole, a resilient connection pivotally hinging the floating valve 205 to the valve seat 215.

In the advantageous embodiment illustrated in attached drawings, thanks to pegs 220_P1,220_P1 resiliency, fitting by interference between the pegs 220_P1,220_P1 and the housings 205_H1,205_H2 may be achieved by any proper sizing and/or shaping thereof. For example, as can be best appreciated in Figures 2D and 2E, each peg 220_P1,220_P1 preferably features an (e.g., enlarged) interference portion 220_PE1,220_PE2 adapted to elastically deform while passing through the housings 205_H1,205_H2, and to avoid, after its passage, that the floating valve 205 slides down along the pegs 220_P1,220_P1.

Preferably, said fitting is with mechanical play, which compensates unavoidable mechanical tolerances and facilitates opening of the floating valve 205 - indeed, thanks to their resiliency, pegs 220_P1,220_P1 inflect due to floating valve 205 weight. Pegs 220_P1,220_P1 inflection, apart from further facilitating opening of the floating valve 205, also provides a dumping effect against damages and noise that contact between floating valve 205 and the receptacle 210_R could cause.

Moreover, by choosing the pegs 220_P1,220_P1 resilient and long enough to intercept at least part of the floating valve 205 when in the opened position, the pegs 220_P1,220_P1 also feature a noise-suppression capability. Elongated pegs, such as the illustrated pegs 220_P1,220_P1, are in fact adapted, in use, to be interposed between the floating valve 205 and the a receptacle 210_R, so as to soften (thereby suppressing noise caused by, and preserving integrity of) the floating valve 205 banging against the receptacle 210_R when switching from closed to opened positions and during highly stressing operations of the washing machine 100.

As can be appreciated in Figure 2E, the floating valve 205 preferably comprises a number N of air capturing chambers or cavities 205_Ci (i=1, 2, ... N, with N=8 in the example at issue) adapted to capture air for efficient floating thereof. In fact, during closing of the floating valve 205, water column pushes air contained within the discharge system upwards.

Cavities 205_Ci are delimited by one or more walls extending from a rear side of the floating valve 205 (i.e., the side intended to intercept the water column and the air from the discharge system) opposite to a front, abutment side thereof (i.e., the side intended to abut, at least partly, against the valve seat 215 in the closed position). In the exemplary, not limiting, illustrated embodiment, a substantially circular outer wall 205_OW and four rectilinear inner walls (globally denoted by the number reference 205_IW) crosspiece arranged within the outer wall 205_OW are advantageously provided, which define eight cavities 205_C1-205_C8 - however, a lower number of rectilinear inner walls, as well as different shaping and arrangement thereof, can be provided in alternative advantageous embodiments, not shown.

As mentioned above, the valve seat 215 (together with the associated floating valve 205) is advantageously mounted, preferably hinged, on the open end of the receptacle 210_R, preferably by means of hinge elements 210_H and 215_H1 provided, respectively, on the open end of the receptacle 210_R (preferably, made in a single piece construction with it) and on the lower surface of the valve seat 215 (preferably, made in a single piece with it). Provision of the hinge elements 210_H,215_H1 allows the floating valve 205/valve seat 215 group to be pivotally rotated (about a corresponding hinge axis, not shown) onto the open end of the receptacle 210_R (as illustrated in the top drawing of Figure 2F), and away from it (as illustrated in the bottom drawing of Figure 2F), so that opening and servicing of the valve/filter assembly 145 is allowed without having to completely detach the valve seat 215 therefrom.

The valve/filter assembly 145 further advantageously comprises one or more removable fixing elements adapted for removably fixing both said receptacle 210_R to the valve seat 215 and the valve/filter assembly 145 to the filter seat 150 (as discussed herebelow). Preferably, said one or more removable fixing elements comprise at least one lip 210_L1,210_L2 provided at said receptacle 210_R and advantageously elastically deformable in such a way to allow, by elastic deformation thereof, the insertion and the snap-fixing fixation of said receptacle 210_R in said filter seat 150.

In the advantageous exemplary illustrated embodiment, two lips 210_L1,210_L2 extend upwards from opposite sides of the open end of the receptacle 210_R (thus resulting substantially, i.e. approximately, parallel to each other), preferably (as illustrated) at the projecting portions 210_P1,210_P2, respectively. Preferably, the lips 210_L1,210_L2 are made of a semi-rigid material, more preferably they are made of the same material as the receptacle 210_R, and even more preferably they are made in a single piece construction with it. Thus, upon exerting a slight force (e.g. a compression force) along the longitudinal direction X between lips 210_L1,210_L2, the receptacle 210_R and the projecting portions 210_P1,210_P2 undergo a corresponding deformation that allows passage thereof through the seat opening, thereafter, upon releasing said force, the receptacle 210_R and the projecting portions 210_P1,210_P2, as getting back to their natural shapes, come into contact with the sump inner flange 150_F (and occlude the seat opening, as illustrated in Figures 2B and 2C).

As can be best appreciated in Figure 2B and in the top drawing of Figure 2E, at least a peripheral region of the valve seat 215 is preferably intended to contact the sump inner flange 150_F thus preventing further fitting of the valve/filter assembly 145 into the seat opening. Thus, the valve seat 215 (or at least part thereof) is advantageously adapted to rest, upon positioning said valve/filter assembly 145 in said filter seat 150, on the sump inner flange 150_F, while the removable fixing elements (i.e., the lips 210_L1,210_L2) engage the sump inner flange 150_F for fixing of the valve/filter assembly 145 in the filter seat 150.

Preferably, the gasket element 220 extends over the whole lower surface of the valve seat 215, so that the valve seat 215 (i.e., the peripheral region thereof) advantageously contacts the sump inner flange 150_F by interposition of the gasket element 220, which greatly improves sealing properties.

As visible also in Figure 2A, the valve seat 215 preferably comprises one or more (e.g., two) slots 215_S1,215_S2 adapted to allow passage of the lips 210_L1,210_L2 therethrough when the valve seat 215 is fixed to the receptacle 210_R (e.g., in the advantageous embodiment illustrated in the attached figures, when the floating valve 205/valve seat 215 group is pivotally rotated onto the open end of receptacle 210_R). Specifically, when a force is applied to the lips 210_L1,210_L2, the lips 210_L1,210_L2 are allowed to pass through the slots 215_S1,215_S2 and to engage the valve seat 215 (by abutting against slots 215_S1,215_S2 wall) when said force is released (dually, as discussed above, the valve/filter assembly 145, i.e., the receptacle 210_R thereof, is allowed to pass, when a force is applied to the lips 210_L1,210_L2, into the seat opening and to engage said filter seat 150 when said force is released).

As should be readily understood, slots 215_S1,215_S2 arrangement, shape and size correspond respectively to lips 210_L1,210_L2 arrangement, shape and size, and implicitly provide also a first indication about alignment and orientation of the valve seat 215 on the receptacle 210_R). In the advantageous example herein considered, the slots 215_S1,215_S2, preferably rectangular-shaped, are arranged at opposite sides of the valve seat 215.

Preferably, as illustrated in the same figures, alignment of the valve seat 215 on the receptacle 210_R is also assisted by a number of (e.g., four) flaps 210_F1-210_F4 (preferably made in a single piece construction with the receptacle 210_R, and arranged along, and preferably extending upwards from, the open end thereof) and by a number of (e.g., four) corresponding wall portions 215_W1,215_W4 (preferably made in a single piece with the valve seat 215, and preferably arranged along, and extending downwards from, the lower surface of the valve seat 215), adapted to cooperate (e.g., by slide contact) with each other.

The valve/filter assembly 145 further preferably comprises a locking element 225 adapted to be interlocked with the valve seat 215.

The locking element 225 is preferably adapted to be locked on the valve seat 215 (i.e., on an upper surface thereof opposite the lower surface) so as to press/push the valve seat 215 on the sump inner flange 150_F (and, especially, the gasket element portion therebetween), thus providing effective retaining and sealing actions. Preferably, the locking element 225 is made of a rigid or semi-rigid material, so as to provide effective pressing/pushing action and, hence, ensuring mechanical stability to the valve/filter assembly 145.

Preferably, the locking element 225 is further adapted to prevent, in the locking position (shown in the top drawing of Figure 2F and in the bottom drawing of Figure 2G), removal of the fixation of the receptacle 210_R to said a valve seat 215 and of the fixation of said valve/filter assembly 145 to said filter seat 150.

In order to achieve that, one or more (e.g., two) cap members 225_C1,225_C2 removably fixable to said valve seat 215 are preferably provided for covering at least a part of the valve seat 215, and even more preferably (as illustrated in Figures 2A, 2B, 2C, 2D and 2F) the cap members 225_C1,225_C2 are shaped and sized for covering the slots 215_S1,215_S2 and the lips 210_L1,210_L2 therethrough. Thanks to the cap members 225_C1,225_C2, accidental access to the lips 210_L1,210_L2 is prevented, so that fixation of the receptacle 210_R to the valve seat 215 and fixation of the valve/filter assembly 145 to the filter seat 150 is ensured.

Still more preferably, as can be best appreciated in Figures 2A and 2F, each cap member 225_C1,225_C2 is adapted to be fitted into a corresponding peripheral recess 215_SR1,215_SR2 of the slot 215_S1,215_S2 exposing a corresponding region of the gasket element 220 underneath it. Thus, by advantageously making the cap members 225_C1,225_C2 of a rigid or semi-rigid material, high friction is experienced upon contact with the gasket element 220, so that increased sealing action is achieved, and treatment liquid leakages are prevented through the slots 215_S1,215_S2.

Preferably, as illustrated, the cap members 225_C1,225_C2 are made in a single piece with the locking element 225, so that easy covering is automatically achieved upon interlocking between the locking element 225 and the valve seat 215.

Advantageously, the locking element 225 is shaped and sized so as not to obstruct or make it difficult the passage of the treatment liquids through the valve/filter assembly 145 (i.e., through the inlet thereof). In this respect, as can be better appreciated in the bottom drawing of Figure 2F, the locking element 225 is preferably in the form of a shaft extending, along a longitudinal direction Y substantially orthogonal to the transversal direction X, across opposite side ends of the valve seat 215, and preferably having, along the transversal direction X, a size lower than valve/filter assembly inlet size.

Preferably, as illustrated, the locking element 225 is hingedly mounted on the upper surface of the valve seat 215, which allows unfitting, opening and servicing of the valve/filter assembly 145 without having to completely detach the locking element 225 from the valve seat 215 (as also visible in the bottom drawing of Figure 2F). In order to achieve that hinge elements 215_H2 and 225_H are preferably provided on the upper surface of the valve seat 215 (preferably, made in a single piece with it) and as an end portion of the locking element 225, respectively.

Interlocking between the locking element 225 and the valve seat 215 is preferably achieved by means of a snap-fit mechanism. As can be better appreciated in Figures 2A, 2D, 2E, 2F and 2G, the snap-fit mechanism preferably comprises, at valve seat 215 side, a guiding element 215_G provided with a housing (e.g., a slot) 215_GS, and, at locking element 225 side (e.g., opposite the hinge element 225_H), a hand-grip element 225_HG provided with a cantilevered portion 225_HGc. As can be better appreciated in the close-up views of Figure 2G, the hand-grip element 225_HG is preferably adapted to slide within the guiding element 215_G until the cantilevered portion 225_HGc snap-fit engages the guiding element slot 215_GS. As should be readily understood, sizing and/or shaping of the snap-fit mechanism directly affect the pressing/pushing action the locking element 225 is able to impart on the valve seat 215 when interlocked to each other, thus directly affecting compression of the gasket portion between the valve seat 215 and the sump inner flange 150_F, and hence sealing action thereof against treatment liquids leakages.

Preferably, the guiding element 215_G is made in a single piece construction with the valve seat 215, and the hand-grip element 225_HG is made in a single piece construction with the locking element 225. In this case, as should be readily understood, at least one between the valve seat 215 and the locking element 225 is conveniently made of a semi-rigid material, so that (even slight) resiliency allows imparting a deformation causing the cantilevered portion 225_HGc to snap-fit engage the guiding frame slot 215_GS easily.

However, in the particular embodiment herein illustrated wherein the hand-grip element 225_HG advantageously features an elbow-shaped portion, the valve seat 215 and the locking element 225 may instead be made both of a rigid material, as the elbow-shaped portion may advantageously give, alone, the hand-grip element 225_HG with a sufficient degree of deformation capabilities.