APPLIANCE

Field of the invention

The present invention generally relates to the field of laundry treatment appliances, hereinafter laundry appliances, both for domestic and professional use.

Even more particularly, the present invention relates to a gasket/floating valve assembly for use in discharge systems of such laundry appliances.

Background of the invention

A typical laundry appliance (e.g. , washing machine, washing/drying machine) comprises a rotatable drum accessible by a user for loading/unloading laundry, a tub (housing the drum), adapted to be filled with treatment liquids (e.g. , washing water, detergent-water solutions, or rinsing water) for laundry treatment, and a discharge system, connected to a tub outlet arranged at the bottom of the tub, for discharging the treatment liquids after laundry treatment fulfillment.

According to a known implementation, the discharge system comprises a flexible sleeve connected to the tub outlet for receiving the treatment liquids, a filter (e.g. , arranged downstream the sleeve and fluidly connected thereto) for filtering the treatment liquids from possible foreign bodies and/or lint, a motor driven pump for promoting the treatment liquids draining, and a discharge hose for discharging the filtered treatment liquids into the sewer network.

In a common operation mode, the discharge system is preliminarily fed with an amount of water (hereinafter, water column) sufficient to completely fill the sleeve. Then, in order to start laundry treatment, the tub is fed with the treatment liquids, whose discharge is prevented by the water column itself.

However, sleeve flexibility causes water column shaking, which greatly reduces its discharge prevention action. Thus, in many laundry appliances a, e.g. ball-shaped, floating valve is upwards/downwards moveably arranged inside the sleeve for selectively closing/opening the tub outlet.

During operation, as water level inside the sleeve increases, the floating valve, due to the experienced push action, ascends by floating, until closing the tub outlet. Upon pump activation (e.g. , after laundry treatment fulfillment), water column is discharged. Thus, the floating valve, as failing the push action exerted on it, descends by gravity, thereby allowing the treatment liquids to be discharged through the discharge system.

Summary of the Invention

The Applicant has found that the known and practiced laundry appliances based on the above-described discharge system are not satisfactory.

More particularly, the Applicant has ascertained that floating valve closing is inefficient. Indeed, during its ascending movement, the floating valve experiences friction with the sleeve, until getting jammed, so that the push action exerted by water column may not be sufficient to completely close the tub outlet.

Moreover, sleeve flexibility poses reliability issues and makes discharge system assembling unpractical. Indeed, sleeve connection with other (rigid) components releases by time because of mechanical stress affecting the laundry appliance during its operation.

The Applicant has also noticed that current alternative solutions are not adequate.

For example, some laundry appliances are provided with a discharge system comprising a rigid (e.g. , plastic) connection manifold, in place of the sleeve/floating valve assembly, connecting the tub with the downstream components.

A manifold inlet is connected to the tub outlet - for example, by interposition of a ring-shaped sealing gasket (as disclosed in EP1746193).

Manifold rigidity provides the discharge system with improved mechanical stability (thus allowing good water column action against treatment liquids discharge), as well as assembling ease and compactness.

However, the Applicant has understood that provision of the manifold involves treatment liquids and electric power wastes.

In fact, undissolved detergent may accumulate at the bottom of the tub and enter the discharge system without being used for the laundry treatment. This leads to detergent wasting, which involves insufficient laundry cleaning as well as environmental damages.

Furthermore, during laundry treatment, the treatment liquids in the tub and the water column in the discharge system are in contact with each other at the tub outlet/manifold inlet interface. This causes dispersion of heat during treatment liquids heating, and hence inefficient electric power consumption.

The Applicant has faced the problem of devising a satisfactory solution able to overcome the above-discussed 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 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 the treatment liquids, and a gasket arranged between the manifold inlet and the tub outlet for sealingly {i.e. , in a watertight way) coupling thereof. In the solution according to one or more embodiments of the invention, the laundry treatment appliance further comprises a floating valve, pivotally hinged to the 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 the tub to said manifold, and an opened position wherein the floating valve is at least partially spaced from the valve seat thereby allowing the treatment liquids to pass from the tub to the manifold. The floating valve and the valve seat have different rigidity {i.e. the rigidity, or the resilience, of the valve is different from the rigidity, or the resilience, of the valve seat). Advantageously, one between the floating valve and the valve seat is made of a material having a low rigidity (i.e., a resilient material), for example EPDM or thermoplastic rubber, while the other between the floating valve and the valve seat is made of a material having a high rigidity (i.e. , a material substantially rigid or having a low resilience), for example a thermoplastic resin or a thermosetting resin; the substantially rigid element ensures a stable and substantially not deformable support against which the resilient element abuts in the above mentioned closed position, ensuring in this way a perfect watertight of the closure of the valve.

In a preferred embodiment the gasket and the manifold are two distinct components; in a further advantageous embodiment, the gasket and the manifold are made in a single piece construction (i.e. , they are a single body, obtained, for example by injection molding).

According to an embodiment of the invention, the floating valve is provided with at least one wall that extends from a rear side of the floating valve opposite to an abutment side thereof, the at least one wall delimiting one or more air capturing chambers adapted to capture air thereby enhancing floating of said floating valve.

According to an embodiment of the invention, the at least one wall comprises an outer wall and at least one inner wall arranged within the outer wall.

According to an embodiment of the invention, the at least one inner wall comprises two rectilinear walls crosspiece arranged within the outer wall.

According to an embodiment of the invention, the at least one wall comprises a rectilinear wall portion arranged in proximity to an hinging region of the floating valve to the gasket, and substantially parallel to an hinge axis of the floating valve to the gasket, the rectilinear wall portion hindering, during floating valve opening, the escaping from the one or more capturing chambers of the air captured therein. The rectilinear wall portion is preferably arranged, in use, substantially horizontally (e.g., substantially perpendicularly with respect to a main incidence direction of the air captured in the one or more capturing chambers during opening of the floating valve). Thus, the rectilinear wall portion forms an effective straight barrier preventing (or at least limiting) the air captured in the one or more capturing chambers from climbing over the wall portion itself during opening of the floating valve - on the contrary, should the wall portion be circular, a smaller barrier surface would be opposed to the air with respect to the rectilinear wall portion, so that any significant swinging of the floating valve (e.g. , due to tub mechanical vibrations during appliance operation) could cause air climbing/escaping the small barrier, and thus floating valve opening.

According to an embodiment of the invention, the floating valve is rigid and the valve seat is resilient, the valve seat being made in a single piece with the gasket.

According to an embodiment of the invention, the gasket comprises a protruding member adapted to be associated with a floating valve housing for pivotally hinging the floating valve to the gasket.

According to an embodiment of the invention, the gasket further comprises a noise-suppressing member adapted to at least partially interpose between the floating valve and the manifold when the floating valve is in the opened position, the noise - suppressing member allowing suppressing noise caused by floating valve banging against inner walls of the manifold.

According to an embodiment of the invention, the noise-suppressing member comprises an elongated portion made in a single piece with the protruding member.

According to an embodiment of the invention, a support member is provided for supporting the floating valve, the support member being made in a single piece with the gasket and being pivotable with respect to the valve seat, so that the floating valve/support member assembly is allowed to swing between the closed and opened positions with respect to the gasket.

According to an embodiment of the invention, the support member is shaped such as to keep free at least part of the one or more air capturing chambers of the floating valve.

According to an embodiment of the invention, the gasket is at least partially over-injected on the floating valve.

According to an embodiment of the invention, the floating valve is resilient and the valve seat is rigid, the floating valve being made in a single piece with the gasket. Preferably, but not necessarily, in this embodiment the floating valve/gasket assembly is over-injected on the valve seat.

According to an embodiment of the invention, the gasket embeds a rigid frame for preventing it from excessively deforming during floating valve swinging.

According to an embodiment of the invention, at least one between the floating valve and the valve seat comprises a magnetic member and the other one between the valve seat and the floating valve comprises a magneto-responsive member adapted to magnetically couple with magnetic member for improving adherence between the floating valve and the valve seat and contributing to keep the floating valve in the closed position.

Thanks to the present invention, during laundry treatment detergent is prevented from being wasted (thus limiting the environmental damages), and the treatment liquids are hydraulically and thermally separated from the water column inside the discharge system (thus making efficient treatment liquids heating and electric power consumption).

Another aspect of the solution relates to a floating valve/gasket assembly for use in a laundry treatment appliance. The floating valve is pivotally hinged to the gasket and is adapted to swing between a closed position, wherein the floating valve, by floating on fluids pushing against a rear side thereof, abuts, at an abutment side of the floating valve opposite the rear side, a valve seat associated with the gasket, and an opened position wherein the floating valve is at least partially spaced from said valve seat; the floating valve is provided with at least one wall that extends from the rear side of the floating valve, the at least one wall delimiting one or more air capturing chambers adapted to capture air thereby enhancing floating of said floating valve; this at least one wall comprises a rectilinear wall portion arranged in proximity to an hinging region of the floating valve to the gasket, and substantially parallel to an hinge axis of the floating valve to the gasket, the rectilinear wall portion hindering, during floating valve opening, the escaping from the one or more capturing chambers of the air captured therein. The rectilinear wall portion is preferably arranged, in use, substantially horizontally (e.g. , substantially perpendicularly with respect to a main incidence direction of the air captured in the one or more capturing chambers during opening of the floating valve). Thus, the rectilinear wall portion forms an effective straight barrier preventing (or at least limiting) the air captured in the one or more capturing chambers from climbing over the wall portion itself during opening of the floating valve - on the contrary, should the wall portion be circular, a smaller barrier surface would be opposed to the air with respect to the rectilinear wall portion, so that any significant swinging of the floating valve (e.g. , due to tub mechanical vibrations during appliance operation) could cause air climbing/escaping the small barrier, and thus floating valve opening.

Another aspect of the solution relates to a floating valve/gasket assembly for use in a laundry treatment appliance comprising a rigid tub for containing laundry treatment liquids, a manifold for receiving the treatment liquids, and a gasket arranged between the manifold and the tub for sealingly coupling thereof. The laundry treatment appliance further comprises a floating valve pivotally hinged to the gasket and adapted to swing between a closed position, wherein the floating valve abuts a valve seat associated with the gasket, and an opened position wherein the floating valve is at least partially spaced from the valve seat; the valve/gasket assembly further comprises a noise-suppressing member adapted to at least partially interpose between the floating valve and the manifold when the floating valve is in the opened position, the noise-suppressing member allowing suppressing noise caused by floating valve banging against inner walls of the manifold.

According to an embodiment of the invention, the gasket comprises a protruding member adapted to be associated with a floating valve housing for pivotally hinging the floating valve to the gasket, said noise- suppressing member comprising an elongated portion made in a single piece with the protruding member.

Noise-suppression member is adapted to soften (thereby suppressing noise caused by, and preserving integrity of) the floating valve banging against inner walls of the manifold when switching from closed to opened positions and during highly stressing operations of the appliance (e.g. , spin-dryer operations). In order to achieve that, no specific conditions for valve seat and floating valve rigidities are required. Another aspect of the solution relates to a floating valve/gasket assembly for use in a laundry treatment appliance. The floating valve is pivotally hinged to the gasket and is adapted to swing between a closed position, wherein the floating valve abuts a valve seat associated with the gasket, and an opened position wherein the floating valve is at least partially spaced from the valve seat. In the solution according to one or more embodiments of the invention at least one between the floating valve and the valve seat comprises a magnetic member and the other one between the valve seat and the floating valve comprises a magneto-responsive member adapted to magnetically couple with magnetic member for improving adherence between the floating valve and the valve seat and contributing to keep the floating valve in the closed position.

As before, magnetic and magneto-responsive members can be used regardless from valve seat and floating valve rigidities. Brief Description of the Drawings

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 1A shows a sectional side view of a laundry appliance according to an embodiment of the invention;

Figure IB shows an exploded view of a tub-discharge system assembly of such a laundry appliance, with a gasket/floating valve assembly according to an embodiment of the invention;

Figures 1C and ID show sectional views of a part of the discharge system of Figure IB, with the floating valve in closed and opened positions, respectively;

Figure IE shows a perspective exploded view of the gasket/floating valve assembly of Figures IB- ID;

Figures 2A and 2B show sectional views of a part of the discharge system illustrating a gasket/floating valve assembly according to another embodiment of the invention, with the floating valve in closed and opened configurations, respectively;

Figures 3A and 3B show perspective exploded and assembled views, respectively, of a gasket/floating valve assembly according to another embodiment of the invention;

Figure 4 shows perspective top and bottom views of a gasket/floating valve assembly according to another embodiment of the invention, and

Figure 5 shows a sectional close-up view of a gasket/floating valve assembly according to another embodiment of the invention.

With reference to the drawings, Figure 1A shows a sectional side view of a laundry appliance or, shortly, appliance 100, for example for domestic use, according to an embodiment of the invention. The appliance 100 may be a washing machine (as generically illustrated in the figure, and to which reference will be made in the following by way of a non-limiting example only), or a washer/dryer, for example 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 proposed solution).

In the following, for the sake of description easy and conciseness, reference is jointly made to Figures 1A-1E.

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

In this respect, the appliance 100 comprises a substantially cylindrical-shaped rotating drum 110, configured to rotate for tumbling laundry loaded therein, and an access door 115 for allowing laundry loading/unloading. The drum 110 is enclosed within a (e.g. , rigid, plastic material) tub 120, preferably hollow-cylinder shaped, which is adapted to contain treatment liquids (e.g. , washing water, detergent- water solutions, or rinsing water) for laundry treatment. In the preferred, not limiting, disclosed embodiment, the tub 120 comprises (e.g., hollow half-cylindrical) front 120a and rear 120b half-shell sections (visible from Figure IB), adapted to be coupled with each other (e.g. , by means of pins or bolts) and enclosing the drum 110 therebetween, as well as a tub outlet 120t, e.g. provided at the bottom of the front half-shell section 120a, for draining the treating liquids from the tub 120 - e.g. , after laundry treatment fulfillment.

The appliance 100 further comprises a discharge system adapted to discharge the treatment liquids (drained from the tub 120) into the sewer network (not shown).

In order to achieve that, the discharge system preferably comprises a connection manifold 125 (e.g. , made of rigid or resilient plastic material) for receiving the treatment liquids from the tub 120, a filter 130, arranged downstream the manifold 125 - preferably, at least partly inside it - for filtering the treatment liquids from possible foreign bodies and/or lint, a motor driven pump 135, arranged downstream the filter 130 - preferably, at least partly inside the manifold 125 - for promoting the draining of the treatment liquids, and a discharge hose 140 for discharging the filtered treatment liquids into the sewer network.

As visible from Figures IB-ID, a manifold inlet 125m is sealingly (i.e. , in a watertight way) coupled with the tub outlet 120t (e.g., by means of screws 145) by interposition of a (e.g. , substantially ring-shaped, rubber) gasket 150. The gasket 150, compressed between manifold inlet 125m and tub outlet 120t mating surfaces, completely fills the space therebetween, thus preventing liquids leakages. In the embodiment illustrated in the enclosed drawings, the manifold 125 and the gasket 150 are two distinct components; in a further advantageous embodiment, not illustrated, the gasket 150 and the manifold 125 may be made in a single piece construction (i.e. , a single body obtained, for example, by injection molding, or overmolding of the gasket 150 on the manifold 125, and the like).

In order to achieve easy and correct gasket 150 alignment/centering, gasket 150 preferably features a (e.g. , C-shaped) centering member 150c (see Figures IB and IE) adapted to be associated with (e.g. , engaged to or positioned at) a reference member (not illustrated) of the tub outlet 120t.

During operation, the discharge system is partially filled with an amount of water sufficient to completely fill the manifold 125 (so that a water column forms in the discharge system), thereafter the tub 120 is fed with the treatment liquids for laundry treatment.

Broadly speaking, in order to prevent undissolved detergent from accumulating in the manifold (and then being discharged unused), and to thermally separate the treatment liquids contained in the tub 120 from the water column contained in discharge system, a floating valve 155 is provided that, by floating on (and being pushed by) the water column, closes the tub outlet 120t. In other words, the floating valve 155 is adapted to prevent passage of the treatment liquids from tub 120 to manifold 125 (thus ensuring hydraulic and thermal isolation of the treatment liquids in the tub 120 from the water column in the discharge system), or to allow the discharge of the treatment liquids from the tub 120 when required.

In the proposed solution, the floating valve 155 is pivotally hinged to the gasket 150, so as to swing relative thereto between a closed position (illustrated in Figure 1C), wherein the floating valve 155, pushed by the water column, abuts a valve seat 150s associated with the gasket 150 thereby preventing passage of the treatment liquids from tub 120 to manifold 125, and an opened position (illustrated in Figure ID), wherein the floating valve 155, upon failing the push action thereon (due to water column discharge caused by pump 135 activation), is at least partially spaced from the valve seat 150s (thereby allowing passage of the treatment liquids from tub 120 to manifold 125).

Advantageously, in order to provide effective water column push action, pump 135 is impulsively activated and deactivated just before floating valve 155 closure. This generates (in the discharge system) an "unbalanced" water column that, according to well-known communicating vessels principles, pushes (and keeps pushed) the floating valve 155 against the valve seat 150s. As will be better understood in the following, the floating valve 155 and the valve seat 150s (or at least part thereof, e.g. , a contact/abutment part thereof) are preferably designed for exhibiting substantially different rigidity/resiliency - i.e. , they are made of materials having sufficiently different rigidity/resiliency to ensure good and firm adherence upon contact thereof. In fact, when contacted by a rigid member, a resilient member is caused to elastically deform, thereby compensating manufacturing tolerances (and ensuring hydraulic sealing).

Any proper material can be used without departing from the scope of the invention. By way of example only, resilient materials such as rubber, and rigid (or semi-rigid) materials such as polypropylene, polyethylene, metal, polycarbonate can be used.

Considering for example Figure IE, the floating valve 155 is advantageously rigid (e.g. , it is made of a rigid plastic material), whereas the valve seat 150s is advantageously resilient, being for example made of a rubber, and preferably over- injected (at least partially) on the floating valve 155. Thus, due to different rigidity/resiliency that rubber and plastic exhibit, the floating valve 155 and the valve seat 150s experience highly effective friction and adherence upon their contact.

Preferably, the valve seat 150s is made in a single piece (i.e., made in a single body) with the gasket 150, and it is preferably an inner circular flange thereof.

The floating valve 155 preferably comprises a number N of air capturing chambers or cavities 155c; 0=1, 2, ... N, with N=4 in the example at issue) adapted to capture air for efficient floating thereof. In fact, during closing of the floating valve 155, water column pushes air contained within the discharge system upwards.

Cavities 155c; are delimited by one or more walls extending from a rear side 155r of the floating valve 155 (i. e. , the side intended to intercept the water column and the air from the discharge system) opposite to a front, abutment side 155f thereof (i.e. , the side intended to abut against the valve seat 150s and close the tub outlet 120t). In the exemplary, not limiting, illustrated embodiment, an outer wall 160 and one or more inner walls 165 arranged within the outer wall 160 are provided. According to the preferred illustrated embodiment, two rectilinear inner walls 165 are provided, preferably crosspiece arranged within the outer wall 160 so as to define four cavities 155ci,155c ₂ ,155c ₃ ,155c ₄ - however, more than two rectilinear inner walls can be provided in alternative embodiments, not shown.

The outer wall 160 may have a circular shape, or, as illustrated, a circular segment shape, where the outer wall 160 (mainly circular-shaped) comprises a rectilinear wall portion 160p arranged in proximity to an hinging region (denoted by reference H) of the floating valve 155 to the gasket 150, and substantially parallel to an hinge axis XH- Circular segment shape should be preferred as the rectilinear wall portion 160p hinders, during floating valve 155 opening, the escaping from the cavities 155c; of the air captured therein. As inferred from the figure, being arranged substantially horizontally, the rectilinear wall portion 160p forms an effective straight barrier preventing (or at least limiting) the air captured in the cavities 155c, from climbing over it (and hence escaping) during opening of the floating valve 155.

The floating valve 155 also comprises an appendix 170 for easy and reliable hinging thereof to the gasket 150. In this respect, the gasket 150 preferably features a (preferably resilient, e.g. made of rubber) protruding member (preferably, as illustrated, a peg) 150p adapted to be fitted into a floating valve housing (e.g. , a hole 170h of the appendix 170).

In order to achieve this fitting, peg 150p preferably comprises an (e.g. , enlarged) interference portion 150ρκ (see Figure IE) adapted to elastically deform while passing through the hole 170h, and to avoid, after its passage, that the floating valve 155 slides down along the peg 150p.

Preferably, said fitting is with mechanical play, which compensates unavoidable mechanical tolerances and facilitates opening of the floating valve 155 - indeed, thanks to its resiliency, peg 150p inflects due to floating valve 155 weight. Peg 150p inflection, apart from further facilitating opening of the floating valve 155, also provides a dumping effect against damages and noise that contact between floating valve 155 and inner walls of the manifold 125 could cause.

As visible from Figure IE, gasket 155 preferably comprises (preferably made in a single piece with it) an air duct D adapted to fluidly connect, in operation, the manifold 125 with the tub 120.

Provision of such air duct D, although not necessary, is advantageous for making floating valve 155 closure efficient.

In fact, in case that the pump 145 is impulsively activated and deactivated for generating the "unbalanced" water column, exceeding air that opposes to water column push action may result in the manifold 125. Thanks to air duct D, such exceeding air is vented out of the manifold 125 (into the tub 120) during swinging of the floating valve 155 towards the closed position.

As illustrated in the Figures 2A and 2B embodiment, a gasket 250 may be provided having a noise-suppression member, preferably in the form of an elongated portion 250p made in a single piece with the protruding member 150p (so as to form an elongated protruding member or peg 150p,250p). The elongated peg 150p,250p is adapted, in use, to soften (thereby suppressing noise caused by, and preserving integrity of) the floating valve 155 banging against inner walls of the manifold 125 when switching from closed to opened positions and during highly stressing operations of the appliance (e.g. , spin-dryer operations).

Preferably, as illustrated, the elongated peg 150p,250p is resilient and long enough to bend upon contact with the inner walls of the manifold 125 (see Figure 2A), and to elastically intercept at least part of the floating valve 155 when in the opened position (see Figure 2B).

In the exemplary illustrated embodiment, the elongated portion 250p is made of rubber, although other implementations are possible. For example, according to another embodiment of the invention, not shown, the elongated portion 250p might be coupled with the peg 150p by interposition of a rigid, e.g. elbow-shaped, intermediate portion.

As should be readily understood, noise-suppression member may also be incorporated in those embodiments (such as the following ones) where no peg is provided for hinging purposes.

Turning now to Figures 3A and 3B, they show perspective exploded and assembled views, respectively, of a gasket 350/floating valve 355 assembly according to another embodiment of the invention.

The floating valve 350 is made of rigid (e.g. , plastic) material, whereas the gasket 350 (and the valve seat 350s thereof) is of resilient (e.g. , rubber) material.

In such embodiment, a support member (e.g. , a collar) 375 is provided for supporting the floating valve 355 thereby providing mechanical stability thereof. The collar 375, hinged to the gasket 350 (and, preferably, made in a single piece with it), is adapted to hold/support the floating valve 350 so as to swing integral thereto between the closed and opened positions with respect to the gasket 350.

In this respect, the floating valve 355 comprises a number of (e.g. , two) protruding pins 380 adapted to engage (e.g. , by interference fitting, as illustrated, or by over-injection) corresponding housings (e.g. , holes) 375h of the collar 375 (only one visible in the figures)

Preferably, as illustrated, the collar 375 is shaped such as to match the outer 360 and inner 365 walls of the cavities 355c,- (and leave them free as much as possible for allowing optimal air capturing).

Turning now to Figure 4, perspective top and bottom views of a gasket 450/floating valve 455 assembly according to another embodiment of the invention are shown.

In the illustrated embodiment, the floating valve 455 and the gasket 450 are both made of resilient (e.g. , rubber) material, whereas the valve seat 450s is in made of rigid (e.g. , plastic) material.

Preferably, the floating valve 455 (illustrated as comprising four cavities 450c; delimited by an outer circular wall 460 and two inner rectilinear walls 465 crosspiece arranged therewithin by way of example only), is resilient (e.g. , made in a single piece with the gasket 450), whereas the valve seat 450s comprises a plastic, rigid disc formed at an inner perimeter of the gasket 450 (for example, by over- injecting the floating valve 455/gasket 450 assembly on the valve seat 450s).

Anyway, although not shown, the rigid valve seat 450s may also extend, at least partly, within the gasket 450 - e.g. , for preventing it from excessively deforming during floating valve 455 swinging, and/or for manufacturing issues. To the same purpose, according to the floating valve 555/gasket 550 embodiment illustrated in the sectional close-up view of Figure 5, a rigid frame 585 may be provided completely embedded in the gasket 550 (made of rubber).

Advantageously, the rigid frame 585 may be a magnetic member (i.e. , able to generate a magnetic field, such as a permanent magnet), whereas the floating valve 555 (preferably made of rubber as well) may advantageously comprise a magneto- responsive member 590 (i.e. , able to be attracted by the magnetic field generated by magnetic member 585, such as a ferromagnetic member or a permanent magnet) - as should be readily understood, the magnetic member 585 and magneto-responsive member 590 can have different arrangement (for example, they may be in the gasket 550 and in the floating valve 555, respectively, or both). In operation, the magneto- responsive member 590 is thus adapted to magnetically couple with magnetic member 585, thereby improving adherence between the floating valve 555 and the valve seat 550s and contributing to keep the floating valve 555 in the closed position.

As should be readily understood, provision of the magnetic member 585 and of the magneto-responsive member 590 is independent from shape, structure and materials of the floating valve/gasket assembly, as well as from the other advantageous technicalities herein described (e.g., provision of the air chambers, of the peg, and/or of the noise- suppressing member).

By way of example only, it is possible to provide that the magnetic member

585 and the magneto-responsive member 590 are arranged in a completely rigid floating valve/gasket assembly (in which case, the peg is not necessary, and good and firm adherence between the floating valve and the valve seat, although both made of a rigid material, could be ensured by magnetic coupling), and/or that the air capturing chambers are not provided (e.g., in case that the magnetic coupling is strong enough to occur upon relatively low push action exerted on the floating valve by the water column).