Patent Description:
Conventional dishwashers perform cycles of operation on items present in the dishwasher, and have a drain assembly that drains fluids from a sump of the dishwasher to a discharge outlet.

<CIT> and <CIT> disclose a check valve assembly according to the preamble of independent claim <NUM>.

An aspect of the invention relates to a a check valve assembly configured to be located within a pump discharge passageway of a drain pump, said drain pump being configured to transfer fluid from a sump, through a volute having a pump discharge passageway extending from the volute, the check valve assembly, comprising: a seat assembly having a body with a first distal end and a second distal end, a fluid passage extending through the body, the body defining a valve seat having a sealing surface about the fluid passage; and a flapper assembly operably coupled to the seat assembly and having a moveable portion configured to selectively move between a closed position where the moveable portion seals against the sealing surface and an opened position where the moveable portion raises to allow liquid through the fluid passage, wherein the first distal end extends lengthwise beyond the valve seat to define an extension that is configured to prevent insertion of a drain hose past the first distal end within the pump discharge passageway, and wherein an outer edge and a ramped portion of the second distal end of the body form a portion of a geometry of the volute when the check valve assembly is located within the discharge passageway.

Another aspect of the invention relates to a drain assembly for a dishwasher having a tub, a sump fluidly coupled to the tub, and a discharge outlet, the drain assembly comprising: a drain pump having an impeller to pump fluid from the sump to the discharge outlet; a volute body operably coupled to at least a portion of the drain pump and having an interior at least partially defining a volute for the drain pump, the volute fluidly coupling the sump and having a pump discharge passageway fluidly coupled with the discharge outlet; and a check valve assembly located in the pump discharge passageway as described above.

<FIG> illustrates an automatic dishwasher <NUM> capable of implementing an automatic cycle of operation to treat dishes. As used in this description, the term "dish(es)" is intended to be generic to any item, single or plural, that can be treated in the dishwasher <NUM>, including, without limitation, dishes, plates, pots, bowls, pans, glassware, and silverware. As illustrated, the dishwasher <NUM> is a built-in dishwasher implementation, which is designed for mounting under a countertop. However, this description is applicable to other dishwasher implementations such as a stand-alone, drawer-type or a sink-type, for example.

The dishwasher <NUM> has a variety of systems, some of which are controllable, to implement the automatic cycle of operation. A chassis is provided to support the variety of systems needed to implement the automatic cycle of operation. As illustrated, for a built-in implementation, the chassis includes a frame in the form of a base <NUM> on which is supported a open-faced tub <NUM>, which at least partially defines a treating chamber <NUM>, having an open face <NUM>, for receiving the dishes. A closure in the form of a door assembly <NUM> is pivotally mounted to the base <NUM> for movement between opened and closed positions to selectively open and close the open face <NUM> of the tub <NUM>. Thus, the door assembly <NUM> provides selective accessibility to the treating chamber <NUM> for the loading and unloading of dishes or other items.

The chassis, as in the case of the built-in dishwasher implementation, can be formed by other parts of the dishwasher <NUM>, like the tub <NUM> and the door assembly <NUM>, in addition to a dedicated frame structure, like the base <NUM>, with them all collectively forming a uni-body frame to which the variety of systems are supported. In other implementations, like the drawer-type dishwasher, the chassis can be a tub that is slidable relative to a frame, with the closure being a part of the chassis or the countertop of the surrounding cabinetry. In a sink-type implementation, the sink forms the tub and the cover closing the open top of the sink forms the closure. Sink-type implementations are more commonly found in recreational vehicles.

The systems supported by the chassis, while essentially limitless, can include dish holding system <NUM>, spray system <NUM>, recirculation system <NUM>, drain system <NUM>, water supply system <NUM>, drying system <NUM>, heating system <NUM>, and filter system <NUM>. These systems are used to implement one or more treating cycles of operation for the dishes, for which there are many, and one of which includes a traditional automatic wash cycle.

A basic traditional automatic wash cycle of operation has a wash phase, where a detergent/water mixture is recirculated and then drained, which is then followed by a rinse phase where water alone or with a rinse agent is recirculated and then drained. An optional drying phase can follow the rinse phase. More commonly, the automatic wash cycle has multiple wash phases and multiple rinse phases. The multiple wash phases can include a pre-wash phase where water, with or without detergent, is sprayed or recirculated on the dishes, and can include a dwell or soaking phase. There can be more than one pre-wash phases. A wash phase, where water with detergent is recirculated on the dishes, follows the pre-wash phases. There can be more than one wash phase; the number of which can be sensor controlled based on the amount of sensed soils in the wash liquid. One or more rinse phases will follow the wash phase(s), and, in some cases, come between wash phases. The number of wash phases can also be sensor controlled based on the amount of sensed soils in the rinse liquid. The wash phases and rinse phases can included the heating of the water, even to the point of one or more of the phases being hot enough for long enough to sanitize the dishes. A drying phase can follow the rinse phase(s). The drying phase can include a drip dry, heated dry, condensing dry, air dry or any combination.

A controller <NUM> can also be included in the dishwasher <NUM> and operably couples with and controls the various components of the dishwasher <NUM> to implement the cycle of operation. The controller <NUM> can be located within the door assembly <NUM> as illustrated, or it can alternatively be located somewhere within the chassis. The controller <NUM> can also be operably coupled with a control panel or user interface <NUM> for receiving user-selected inputs and communicating information to the user. The user interface <NUM> can include operational controls such as dials, lights, switches, and displays enabling a user to input commands, such as a cycle of operation, to the controller <NUM> and receive information.

The dish holding system <NUM> can include any suitable structure for holding dishes within the treating chamber <NUM>. Exemplary dish holders are illustrated in the form of upper dish racks <NUM> and lower dish rack <NUM>, commonly referred to as "racks," which are located within the treating chamber <NUM>. The upper dish racks <NUM> and the lower dish rack <NUM> are typically mounted for slidable movement in to and out of the treating chamber <NUM> through the open face <NUM> for ease of loading and unloading. Drawer guides/slides/rails <NUM> are typically used to slidably mount the upper dish rack <NUM> to the tub <NUM>. The lower dish rack <NUM> typically has wheels or rollers <NUM> that roll along rails <NUM> formed in sidewalls of the tub <NUM> and onto the door assembly <NUM>, when the door assembly <NUM> is in the opened position.

Dedicated dish holders can also be provided. One such dedicated dish holder is a third level rack <NUM> located above the upper dish rack <NUM>. Like the upper dish rack <NUM>, the third level rack is slidably mounted to the tub <NUM> with drawer guides/slides/rails <NUM>. The third level rack <NUM> is typically used to hold dishes in the form of utensils, such as tableware, spoons, knives, spatulas, etc., in an on-the-side or flat orientation. However, the third level rack <NUM> is not limited to holding utensils. If an item can fit in the third level rack, it can be washed in the third level rack <NUM>. The third level rack <NUM> generally has a much shorter height or lower profile than the upper and lower dish racks <NUM>, <NUM>. Typically, the height of the third level rack is short enough that a typical glass cannot be stood vertically in the third level rack <NUM> and have the third level rack <NUM> still slide into the treating chamber <NUM>.

Another dedicated dish holder can be a silverware basket (not shown), which is typically carried by one of the upper or lower dish racks <NUM>, <NUM> or mounted to the door assembly <NUM>. The silverware basket typically holds utensils and the like in an upright orientation as compared to the on-the-side or flat orientation of the third level rack <NUM>.

A dispenser assembly <NUM> is provided to dispense treating chemistry, e.g. detergent, rinse agent, anti-spotting agent, etc., into the treating chamber <NUM>. The dispenser assembly <NUM> can be mounted on an inner surface of the door assembly <NUM>, as shown, or can be located at other positions within the chassis. The dispenser assembly <NUM> can dispense one or more types of treating chemistries. The dispenser assembly <NUM> can be a single-use dispenser or a bulk dispenser, or a combination of both.

Turning to <FIG>, the spray system <NUM> is provided for spraying liquid in the treating chamber <NUM> and can have multiple spray assemblies or sprayers, some of which can be dedicated to a particular one of the dish holders, to a particular area of a dish holder, to a particular type of cleaning, or to a particular level of cleaning, etc. The sprayers can be fixed or movable, such as rotating, relative to the treating chamber <NUM> or dish holder. Six exemplary sprayers are illustrated and include, an upper spray arm <NUM>, a lower spray arm <NUM>, a third level sprayer <NUM>, a deep-clean sprayer <NUM>, and a spot sprayer <NUM>. The upper spray arm <NUM> and lower spray arm <NUM> are rotating spray arms, located below the upper dish rack <NUM> and lower dish rack <NUM>, respectively, and rotate about a generally centrally located and vertical axis. The third level sprayer <NUM> is located above the third level rack <NUM> about a longitudinal axis. The third level sprayer <NUM> is illustrated as being fixed, but could move, such as in rotating. In addition to the third level sprayer <NUM> or in place of the third level sprayer <NUM>, the sprayer <NUM> can be located at least in part below a portion of the third level rack <NUM>. The sprayer <NUM> is illustrated as a fixed tube, carried by the third level rack <NUM>, but could move, such as in rotating about a longitudinal axis.

The deep-clean sprayer <NUM> is a manifold extending along a rear wall of the tub <NUM> and has multiple nozzles <NUM>, with multiple apertures <NUM>, generating an intensified and/or higher pressure spray than the upper spray arm <NUM>, the lower spray arm <NUM>, or the third level sprayer <NUM>. The nozzles <NUM> can be fixed or move, such as in rotating. The spray emitted by the deep-clean sprayer <NUM> defines a deep clean zone, which in the illustrated example can be defined along a rear side of the lower dish rack <NUM>. Thus, dishes needing deep cleaning, such as dishes with baked-on food, can be located in the lower dish rack <NUM> to face the deep-clean sprayer <NUM>. The deep-clean sprayer <NUM>, while illustrated as only one unit on a rear wall of the tub <NUM> could comprises multiple units and/or extend along multiple portions, including different walls, of the tub <NUM>, and can be provide above, below or beside any of the dish holders where deep-cleaning is desired.

The spot sprayer <NUM>, like the deep-clean sprayer, can emit an intensified and/or higher pressure spray, especially to a discrete location within one of the dish holders. While the spot sprayer <NUM> is shown below the lower dish rack <NUM>, it could be adjacent any part of any dish holder or along any wall of the tub where special cleaning is desired. In the illustrated location below the lower dish rack <NUM>, the spot sprayer can be used independently of or in combination with the lower spray arm <NUM>. The spot sprayer <NUM> can be fixed or can move, such as in rotating.

These six sprayers are illustrative examples of suitable sprayers and are not meant to be limiting as to the type of suitable sprayers.

The recirculation system <NUM> recirculates the liquid sprayed into the treating chamber <NUM> by the sprayers of the spray system <NUM> back to the sprayers to form a recirculation loop or circuit by which liquid can be repeatedly and/or continuously sprayed onto dishes in the dish holders. The recirculation system <NUM> can include a sump <NUM> and a pump assembly <NUM>. The sump <NUM> collects the liquid sprayed in the treating chamber <NUM> and can be formed by a sloped or recess portion of a bottom wall of the tub <NUM>. The pump assembly <NUM> can include one or more pumps such as recirculation pump <NUM>. The sump <NUM> can also be a separate module that is affixed to the bottom wall and includes the pump assembly <NUM>.

Multiple supply conduits <NUM>, <NUM>, <NUM>, <NUM>, <NUM> fluidly couple the sprayers <NUM>-<NUM> to the recirculation pump <NUM>. A recirculation valve <NUM> can selectively fluidly couple each of the conduits <NUM>-<NUM> to the recirculation pump <NUM>. While each sprayer <NUM>-<NUM> is illustrated as having a corresponding dedicated supply conduit <NUM>-<NUM> one or more subsets, comprising multiple sprayers from the total group of sprayers <NUM>-<NUM>, can be supplied by the same conduit, negating the need for a dedicated conduit for each sprayer. For example, a single conduit can supply the upper spray arm <NUM> and the third level sprayer <NUM>. Another example is that the sprayer <NUM> is supplied liquid by the conduit <NUM>, which also supplies the third level sprayer <NUM>.

The recirculation valve <NUM>, while illustrated as a single valve, can be implemented with multiple valves. Additionally, one or more of the conduits can be directly coupled to the recirculation pump <NUM>, while one or more of the other conduits can be selectively coupled to the recirculation pump with one or more valves. There are essentially an unlimited number of plumbing schemes to connect the recirculation system <NUM> to the spray system <NUM>. The illustrated plumbing is not limiting.

A drain system <NUM> drains liquid from the treating chamber <NUM>. The drain system <NUM> includes a drain pump <NUM> fluidly coupled the treating chamber <NUM> to a drain line <NUM>. As illustrated the drain pump <NUM> fluidly couples the sump <NUM> to the drain line <NUM>.

While separate recirculation and drain pumps <NUM> and <NUM> are illustrated, a single pump can be used to perform both the recirculating and the draining functions. Alternatively, the drain pump <NUM> can be used to recirculate liquid in combination with the recirculation pump <NUM>. When both a recirculation pump <NUM> and drain pump <NUM> are used, the drain pump <NUM> is typically more robust than the recirculation pump <NUM> as the drain pump <NUM> tends to have to remove solids and soils from the sump <NUM>, unlike the recirculation pump <NUM>, which tends to recirculate liquid which has solids and soils filtered away to some extent.

A water supply system <NUM> is provided for supplying fresh water to the dishwasher <NUM> from a household water supply via a household water valve <NUM>. The water supply system <NUM> includes a water supply unit <NUM> having a water supply conduit <NUM> with a siphon break <NUM>. While the water supply conduit <NUM> can be directly fluidly coupled to the tub <NUM> or any other portion of the dishwasher <NUM>, the water supply conduit is shown fluidly coupled to a supply tank <NUM>, which can store the supplied water prior to use. The supply tank <NUM> is fluidly coupled to the sump <NUM> by a supply line <NUM>, which can include a controllable valve <NUM> to control when water is released from the supply tank <NUM> to the sump <NUM>.

The supply tank <NUM> can be conveniently sized to store a predetermined volume of water, such as a volume required for a phase of the cycle of operation, which is commonly referred to as a "charge" of water. The storing of the water in the supply tank <NUM> prior to use is beneficial in that the water in the supply tank <NUM> can be "treated" in some manner, such as softening or heating prior to use.

A water softener <NUM> is provided with the water supply system <NUM> to soften the fresh water. The water softener <NUM> is shown fluidly coupling the water supply conduit <NUM> to the supply tank <NUM> so that the supplied water automatically passes through the water softener <NUM> on the way to the supply tank <NUM>. However, the water softener <NUM> could directly supply the water to any other part of the dishwasher <NUM> than the supply tank <NUM>, including directly supplying the tub <NUM>. Alternatively, the water softener <NUM> can be fluidly coupled downstream of the supply tank <NUM>, such as in-line with the supply line <NUM>. Wherever the water softener <NUM> is fluidly coupled, it can be done so with controllable valves, such that the use of the water softener <NUM> is controllable and not mandatory.

A drying system <NUM> is provided to aid in the drying of the dishes during the drying phase. The drying system as illustrated includes a condensing assembly <NUM> having a condenser <NUM> formed of a serpentine conduit <NUM> with an inlet fluidly coupled to an upper portion of the tub <NUM> and an outlet fluidly coupled to a lower portion of the tub <NUM>, whereby moisture laden air within the tub <NUM> is drawn from the upper portion of the tub <NUM>, passed through the serpentine conduit <NUM>, where liquid condenses out of the moisture laden air and is returned to the treating chamber <NUM> where it ultimately evaporates or is drained via the drain pump <NUM>. The serpentine conduit <NUM> can be operated in an open loop configuration, where the air is exhausted to atmosphere, a closed loop configuration, where the air is returned to the treating chamber, or a combination of both by operating in one configuration and then the other configuration.

To enhance the rate of condensation, the temperature difference between the exterior of the serpentine conduit <NUM> and the moisture laden air can be increased by cooling the exterior of the serpentine conduit <NUM> or the surrounding air. To accomplish this, an optional cooling tank <NUM> is added to the condensing assembly <NUM>, with the serpentine conduit <NUM> being located within the cooling tank <NUM>. The cooling tank <NUM> is fluidly coupled to at least one of the spray system <NUM>, recirculation system <NUM>, drain system <NUM>, or water supply system <NUM> such that liquid can be supplied to the cooling tank <NUM>. The liquid provided to the cooling tank <NUM> from any of the systems <NUM>-<NUM> can be selected by source and/or by phase of cycle of operation such that the liquid is at a lower temperature than the moisture laden air or even lower than the ambient air.

As illustrated, the liquid is supplied to the cooling tank <NUM> by the drain system <NUM>. A valve <NUM> fluidly connects the drain line <NUM> to a supply conduit <NUM> fluidly coupled to the cooling tank <NUM>. A return conduit <NUM> fluidly connects the cooling tank <NUM> back to the treating chamber <NUM> via a return valve <NUM>. In this way a fluid circuit is formed by the drain pump <NUM>, drain line <NUM>, valve <NUM>, supply conduit <NUM>, cooling tank <NUM>, return valve <NUM> and return conduit <NUM> through which liquid can be supplied from the treating chamber <NUM>, to the cooling tank <NUM>, and back to the treating chamber <NUM>. Alternatively, the supply conduit <NUM> could fluidly couple to the drain line <NUM> if re-use of the water is not desired.

To supply cold water from the household water supply via the household water valve <NUM> to the cooling tank <NUM>, the water supply system <NUM> would first supply cold water to the treating chamber <NUM>, then the drain system <NUM> would supply the cold water in the treating chamber <NUM> to the cooling tank <NUM>. It should be noted that the supply tank <NUM> and cooling tank <NUM> could be configured such that one tank performs both functions.

The drying system <NUM> can use ambient air, instead of cold water, to cool the exterior of the serpentine conduit <NUM>. In such a configuration, a blower <NUM> is connected to the cooling tank <NUM> and can supply ambient air to the interior of the cooling tank <NUM>. The cooling tank <NUM> can have a vented top <NUM> to permit the passing through of the ambient air to allow for a steady flow of ambient air blowing over the serpentine conduit <NUM>.

The cooling air from the blower <NUM> can be used in lieu of the cold water or in combination with the cold water. The cooling air will be used when the cooling tank <NUM> is not filled with liquid. Advantageously, the use of cooling air or cooling water, or combination of both, can be selected on the site-specific environmental conditions. If ambient air is cooler than the cold water temperature, then the ambient air can be used. If the cold water is cooler than the ambient air, then the cold water can be used. Cost-effectiveness can also be taken into account when selecting between cooling air and cooling water. The blower <NUM> can be used to dry the interior of the cooling tank <NUM> after the water has been drained. Suitable temperature sensors for the cold water and the ambient air can be provided and send their temperature signals to the controller <NUM>, which can determine which of the two is colder at any time or phase of the cycle of operation.

A heating system <NUM> is provided for heating water used in the cycle of operation. The heating system <NUM> includes a heater <NUM>, such as an immersion heater, located in the treating chamber <NUM> at a location where it will be immersed by the water supplied to the treating chamber <NUM>. The heater <NUM> need not be an immersion heater, it can also be an in-line heater located in any of the conduits. There can also be more than one heater <NUM>, including both an immersion heater and an in-line heater.

The heating system <NUM> can also include a heating circuit <NUM>, which includes a heat exchanger <NUM>, illustrated as a serpentine conduit <NUM>, located within the supply tank <NUM>, with a supply conduit <NUM> supplying liquid from the treating chamber <NUM> to the serpentine conduit <NUM>, and a return conduit <NUM> fluidly coupled to the treating chamber <NUM>. The heating circuit <NUM> is fluidly coupled to the recirculation pump <NUM> either directly or via the recirculation valve <NUM> such that liquid that is heated as part of a cycle of operation can be recirculated through the heat exchanger <NUM> to transfer the heat to the charge of fresh water residing in the supply tank <NUM>. As most wash phases use liquid that is heated by the heater <NUM>, this heated liquid can then be recirculated through the heating circuit <NUM> to transfer the heat to the charge of water in the supply tank <NUM>, which is typically used in the next phase of the cycle of operation.

A filter system <NUM> is provided to filter un-dissolved solids from the liquid in the treating chamber <NUM>. The filter system <NUM> includes a coarse filter <NUM> and a fine filter <NUM>, which can be a removable basket <NUM> residing the sump <NUM>, with the coarse filter <NUM> being a screen <NUM> circumscribing the removable basket <NUM>. Additionally, the recirculation system <NUM> can include a rotating filter in addition to or in place of the either or both of the coarse filter <NUM> and fine filter <NUM>. Other filter arrangements are contemplated such as an ultrafiltration system.

As illustrated schematically in <FIG>, the controller <NUM> can be coupled with the heater <NUM> for heating the wash liquid during a cycle of operation, the drain pump <NUM> for draining liquid from the treating chamber <NUM>, and the recirculation pump <NUM> for recirculating the wash liquid during the cycle of operation. The controller <NUM> can be provided with a memory <NUM> and a central processing unit (CPU) <NUM>. The memory <NUM> can be used for storing control software that can be executed by the CPU <NUM> in completing a cycle of operation using the dishwasher <NUM> and any additional software. For example, the memory <NUM> can store one or more pre-programmed automatic cycles of operation that can be selected by a user and executed by the dishwasher <NUM>. The controller <NUM> can also receive input from one or more sensors <NUM>. Non-limiting examples of sensors that can be communicably coupled with the controller <NUM> include, to name a few, ambient air temperature sensor, treating chamber temperature sensor, water supply temperature sensor, door open/close sensor, and turbidity sensor to determine the soil load associated with a selected grouping of dishes, such as the dishes associated with a particular area of the treating chamber. The controller <NUM> can also communicate with the recirculation valve <NUM>, the household water valve <NUM>, the controllable valve <NUM>, the return valve <NUM>, and the valve <NUM>. Optionally, the controller <NUM> can include or communicate with a wireless communication device <NUM>.

<FIG> illustrates a sump assembly <NUM> that can be included in the dishwasher <NUM> and includes among other things, the sump <NUM> and a recirculation outlet <NUM> configured to receive liquid from the recirculation pump <NUM> and where the recirculation outlet <NUM> can be configured to fluidly couple with the recirculation valve <NUM> and the multiple supply conduits <NUM>, <NUM>, <NUM>, <NUM>, <NUM>. In the illustrated example, the sump <NUM> is defined by a peripheral wall extending upwards from a base.

A drain assembly <NUM> is also illustrated and includes the drain pump <NUM>, the drain line <NUM>, a volute <NUM>, and a check valve assembly <NUM>. As illustrated portions of the sump assembly <NUM> can be a unitary body including that the volute130 can be unitarily formed with the sump <NUM>. By way of non-limiting example, the volute <NUM> can have a first portion <NUM> that operably couples to the drain pump <NUM>, a second portion <NUM> illustrated as a rear surface includes an opening <NUM> that fluidly couples the volute <NUM> to the sump <NUM> and an air vent <NUM>. While the opening <NUM> is D-shaped; it is contemplated that openings having other shapes could be used. The example air vent <NUM> is configured to allow for air to pass therethrough, thereby reducing or preventing air lock conditions. By allowing air to escape, multiple starts and stops of the drain pump <NUM> can be reduced or eliminated, which may increase customer satisfaction.

The volute <NUM> can have and a discharge outlet <NUM> having an opening <NUM> within the volute <NUM> and is operably coupled with the drain line <NUM>. More specifically the drain line <NUM> is illustrated as a hose that can be inserted within the discharge outlet <NUM>. While not specifically shown, it will be understood that an impeller of the drain pump <NUM> fluidly couples the volute <NUM> and can be at least partially received within the volute <NUM>, as the volute <NUM> is the casing that receives the fluid being pumped by the impeller. Further still a diameter <NUM> of the volute <NUM> is illustrated.

A check valve assembly <NUM> for the drain pump <NUM> is also illustrated and includes a seat assembly <NUM> and a flapper assembly <NUM>. The check valve assembly <NUM> includes a stop feature <NUM> that is configured to prevent over-insertion of the drain line <NUM> beyond a predetermined point in the discharge outlet <NUM>. As illustrated, a distal end 64a of the drain line <NUM> abuts the stop feature <NUM> and is prevent from further insertion thereby.

<FIG> illustrates the seat assembly <NUM> and the flapper assembly <NUM> in an exploded view so both can be more easily seen. A body <NUM> of the seat assembly <NUM> extends between a first distal end <NUM> and a second distal end <NUM>. A valve seat <NUM> is formed in a portion of the body <NUM> and the first distal end <NUM> extends lengthwise beyond the valve seat <NUM> to define an extension 158a defining the hose stop feature <NUM>. The extension 158a has a concave upper surface and is configured to prevent insertion of the drain hose <NUM> past the first distal end <NUM>.

An inner diameter <NUM> of the body <NUM> defines a fluid passage <NUM> extending through the body <NUM>. The fluid passage <NUM> extends through the valve seat <NUM> and a sealing surface of the valve seat <NUM> extends about the fluid passage <NUM>. It will be understood that the body <NUM> of the seat assembly <NUM> is illustrated merely in a non-limiting example and that any suitable body can be utilized. In the illustrated example an outside profile <NUM> of the body <NUM> includes a first rib <NUM> spaced from a second rib <NUM> forming a catch <NUM> there between. It will be understood that neither the first rib <NUM> nor the second rib <NUM> need be formed the entire way around the outside profile <NUM> of the body <NUM> of the seat assembly <NUM>. Further still, the first rib <NUM> and/or the second rib <NUM> can have varying contours about the outside profile <NUM> of the body <NUM> of the seat assembly <NUM>. In the illustrated example, the second rib <NUM> is not fully formed at an upper portion of the body <NUM> to allow for portions of the flapper assembly <NUM>.

An alignment feature <NUM> is also provided on the outside profile of the body <NUM> of the seat assembly <NUM>. The alignment feature <NUM> is configured to aid in placement of the check valve assembly <NUM> within the pump discharge passageway <NUM>. More specifically, the alignment feature <NUM> is illustrated as a first contour that is complementary to a second contour within a portion of the pump discharge passageway <NUM>. It will be understood that the alignment feature <NUM> can be any suitable alignment feature. In the instant case the outside perimeter includes a concave contour, profile, or shape forming the alignment feature and a portion of the second distal end and the pump discharge passageway includes a convex contour complementary to the alignment feature <NUM>.

A body <NUM> of the flapper assembly <NUM> includes a ring <NUM> having an inner diameter <NUM> that can be fit about the catch <NUM> such that the ring <NUM> can be retained between the first rib <NUM> and the second rib <NUM>. A hinge <NUM> is operably coupled to ring <NUM> and extends therefrom and operably couples a flapper portion or moveable portion <NUM> having a sealing face <NUM> to the ring <NUM>.

As better seen in the cross-section of <FIG> the sealing face <NUM> of the moveable portion of the flapper assembly <NUM> has a larger diameter than a diameter of the valve seat <NUM>. The moveable portion <NUM> of the flapper assembly <NUM> is moveable between a sealed position and an opened position (shown in phantom). In the sealed position or closed position, the sealing face <NUM> abuts the valve seat <NUM> and a seal is formed at <NUM>. More specifically, the hinge <NUM> allows the moveable portion <NUM> to pivot upwards and downwards at the hinge <NUM>. In the opened position (shown in phantom), the sealing face <NUM> is generally horizontal and aligned with the hinge <NUM> such that the moveable portion <NUM> allows for a flow of liquid through the check valve assembly <NUM>. It can also be seen that the extension 158a, which forms the stop feature <NUM>, has a length that is at least even with an extent of the moveable portion <NUM> when it is located in the opened position (shown in phantom). The concave profile of the stop feature <NUM> also allows for movement of the moveable portion <NUM> there above.

Also illustrated is that the ring <NUM> of the flapper assembly also includes a keyed extension <NUM> that can be received within a corresponding groove portion of the outside profile <NUM> of the body <NUM> of the seat assembly <NUM> such the flapper assembly <NUM> can be properly aligned on the seat assembly <NUM>. It is contemplated that the body <NUM> of the flapper assembly <NUM> can be a unitary body, The body <NUM> of the flapper assembly can be formed from any suitable material including, by way of non-limiting example, silicone, which would allow for the ring <NUM> to be placed within the catch and for the hinge <NUM> to move during operation without tearing.

<FIG> illustrates the flapper assembly <NUM> operably coupled to the seat assembly <NUM> with the ring <NUM> located between the first rib <NUM> and the second rib <NUM>. The view illustrated shows the second distal end <NUM> of the body <NUM> of the seat assembly <NUM> in more clarity. More specifically it can be seen that an outermost edge <NUM> of the distal end is countered and not round. A ramped portion <NUM> leads from the outer edge <NUM> to an entrance <NUM> to the fluid passage <NUM> formed within the body <NUM> of the seat assembly <NUM>. It will be understood that a portion of the alignment feature <NUM> aids in shaping the outer edge <NUM> and the ramped portion <NUM> although this need not be the case. The outer edge <NUM> and ramped portion <NUM> form a portion of a geometry of the volute <NUM> when the check valve assembly <NUM> is located properly within the discharge outlet <NUM>. This can be more clearly seen with respect to <FIG>, which illustrates that the check valve assembly <NUM> has been press fit into the discharge outlet <NUM> and the outer edge <NUM> of the second distal end <NUM> of the body <NUM> of the seat assembly <NUM> is within the opening <NUM> of the discharge outlet <NUM>, extends fully around the opening <NUM>, and sealingly abutted therewith. The outer edge <NUM> and ramped portion <NUM> of the second distal end <NUM> of the body <NUM> of the seat assembly <NUM> forms a portion of the geometry of the volute <NUM>. In the illustrated example, the second distal end <NUM> of the check valve assembly <NUM> is formed such that a profile of the volute <NUM> is not round. This is particularly beneficial during operation because the change in contour provided to the volute <NUM> by the second distal end <NUM> allows for increased operation efficiency as opposed to a round volute. Further still the diameter <NUM> of the volute <NUM> having the contour provided by the second distal end <NUM> at the discharge outlet <NUM> can be decreased in size as compared to that of a round volute. More specifically, in the illustrated example, a <NUM> decrease in diameter (From <NUM> to <NUM>) in the volute <NUM> can be achieved over a round volute and a gain of <NUM> of compression can be achieved.

During operation, liquid is moved from the sump <NUM>, through the opening <NUM> and into the volute <NUM> via the impeller of the drain pump <NUM>. The profile of the second distal end <NUM> of the body <NUM> of the seat assembly <NUM> aids in priming the drain pump <NUM> and increases the performance of the drain pump <NUM>. The impeller of the drain pump <NUM> in turn pushes the liquid through the discharge outlet <NUM> and the check valve assembly <NUM>. More specifically, the liquid is pushed against the moveable portion <NUM>, which rotates the moveable portion <NUM> on the hinge <NUM> from the closed position to the opened position to allow liquid to flow to the drain line <NUM>.

When operation of the drain pump <NUM> ceases, the force created by the liquid on the moveable portion <NUM> also stops and the moveable portion <NUM> returns to the closed position where the sealing face <NUM> abuts the valve seat <NUM> to form a seal that prevents liquid from entering from the drain line <NUM> into the volute <NUM>. In this manner the check valve assembly <NUM> prevents dirty water from entering back into the sump assembly <NUM>.

The inclusion of the volute geometry simplifies the design of the pump volute, while also allowing for changes to the discharge area of the volute by modification of the check valve assembly. This is desirable for making changes in pump performance based on application-specific design criteria, such as pumping efficiency, power consumption, noise level or quality, and passage of objects. The integral stop feature eliminates the problem of an over-inserted connecting hose keeping the check valve from opening completely which would cause pump inefficiency and susceptibility to clogging by foreign objects. Existing pumps do not incorporate part of the pump volute in the valve assembly, precluding simple changes to pump discharge geometry. Existing check valve assemblies do not have an integral hose insertion depth stop. The check valve body also includes a feature to ensure correct alignment in the pump assembly. The check valve assembly components are preassembled and pressed into place in the pump discharge nozzle, allowing for a simple assembly operation during manufacturing. In the illustrated example, a portion of the volute <NUM> lies below a plane defined by the base of the sump <NUM> of the sump assembly <NUM>. Aspects of the present disclosure allow for a compressed size in both vertical and horizontal directions of the drain assembly, while maintaining pump efficiency. For example a majority of the volute <NUM> has been illustrated above a plane defined by the base of the sump <NUM>. The overall height of the pump and sump assemblies was compressed roughly an additional <NUM> with no loss in drain pump performance. Additional side benefits may include simplified tooling of the drain volute and reduced assembly torque due to reduced seal diameter.

Claim 1:
A check valve assembly (<NUM>) configured to be located within a pump discharge passageway (<NUM>) of a drain pump (<NUM>) of a dishwasher (<NUM>), said drain pump (<NUM>) being configured to transfer fluid from a sump (<NUM>), through a volute (<NUM>) having a pump discharge passageway (<NUM>) extending from the volute (<NUM>), the check valve assembly (<NUM>) comprising:
a seat assembly (<NUM>) having a body with a first distal end (<NUM>) and a second distal end (<NUM>), a fluid passage (<NUM>) extending through the body, the body defining a valve seat (<NUM>) having a sealing surface about the fluid passage (<NUM>); and
a flapper assembly (<NUM>) operably coupled to the seat assembly (<NUM>) and having a moveable portion (<NUM>) configured to selectively move between a closed position where the moveable portion (<NUM>) seals against the sealing surface and an opened position where the moveable portion (<NUM>) raises to allow liquid through the fluid passage (<NUM>),
characterized in that the first distal end (<NUM>) extends lengthwise beyond the valve seat (<NUM>) to define an extension (158a) that is configured to prevent insertion of a drain hose (<NUM>) past the first distal end (<NUM>) within the pump discharge passageway (<NUM>),
wherein an outer edge (<NUM>) and a ramped portion (<NUM>) of the second distal end (<NUM>) of the body form a portion of a geometry of the volute (<NUM>) when the check valve assembly (<NUM>) is located within the discharge passageway (<NUM>).