Spray nozzle for a dishwasher appliance

A dishwasher appliance includes a spray nozzle having a housing defining a spray chamber in fluid communication with a fluid circulation assembly. A diversion element is positioned within the spray chamber and is movable between a lowered position and a raised position where it contacts a discharge orifice. The diversion element defines a plurality of flow paths that are randomly oriented relative to the discharge orifice every time the diversion element is moved into the raised position, such as when the fluid circulation assembly cycles off and then on again.

FIELD OF THE INVENTION

The present disclosure relates generally to dishwasher appliances, and more particularly to improved spray assemblies and nozzles for dishwasher appliances.

BACKGROUND OF THE INVENTION

Dishwasher appliances generally include a tub that defines a wash chamber. Rack assemblies can be mounted within the wash chamber of the tub for receipt of articles for washing. Wash fluid (e.g., various combinations of water and detergent along with optional additives) may be introduced into the tub where it collects in a sump space at the bottom of the wash chamber. During wash and rinse cycles, a pump may be used to circulate wash fluid to spray assemblies within the wash chamber that can apply or direct wash fluid towards articles disposed within the rack assemblies in order to clean such articles.

To improve spray coverage, multiple spray arm assemblies can be provided including e.g., a lower spray arm assembly mounted to the tub at a bottom of the wash chamber, a mid-level spray arm assembly mounted to one of the rack assemblies, and/or an upper spray assembly mounted to the tub at a top of the wash chamber. One limitation of many currently known spray arm assemblies is the geometry of the spray arm assemblies and their fixed nozzle positions and orientations. For example, rotating spray arms typically have multiple nozzles positioned along a length of the spray arm. As the spray arm rotates, each nozzle emits wash fluid from a fixed location and direction relative to the arm, generating a predictable and limited circular spray pattern having gaps in spray coverage. These limitations can result in articles not being properly cleaned during operation of the dishwasher appliance.

Spray coverage gaps can be decreased by using more nozzles or by shaping the nozzles as slots to generate a broader spray from each nozzle. However, such nozzle adjustments will result in decreased impingement force unless the hydraulic power is increased. Increasing the hydraulic power results in noisier operation and increased energy consumption. Moreover, increasing the number of nozzles or the spray coverage area of the nozzles increases overall energy and water consumption.

Accordingly, a dishwasher appliance that including improved spray assemblies would be useful. More specifically, improved spray assembly and nozzle designs which increase the coverage of the wash fluid while reducing the noise and energy consumption of a dishwasher appliance would be particularly beneficial.

BRIEF DESCRIPTION OF THE INVENTION

Aspects and advantages of the invention will be set forth in part in the following description, may be apparent from the description, or may be learned through practice of the invention.

In accordance with one exemplary embodiment of the present disclosure, a dishwasher appliance defining a vertical, a lateral, and a transverse direction is provided. The dishwasher appliance includes a wash tub that defines a wash chamber and a wash rack mounted within the wash chamber, the wash rack being configured for receiving articles for washing. A fluid circulation assembly provides a flow of wash fluid for cleaning articles placed within the wash chamber. A spray nozzle includes a housing defining a spray chamber in fluid communication with the fluid circulation assembly, the housing defining a discharge orifice. A diversion element is positioned within the spray chamber, the diversion element defining a plurality of flow paths and being movable between a lowered position and a raised position, at least one of the plurality of flow paths directing the flow of wash fluid through the discharge orifice when the diversion element is in the raised position.

In accordance with another exemplary embodiment of the present disclosure, a spray nozzle for a dishwasher appliance is provided. The dishwasher appliance includes a fluid circulation assembly for selectively urging a flow of wash fluid. The spray nozzle includes a housing defining a spray chamber in fluid communication with the fluid circulation assembly, the housing defining a discharge orifice. A diversion element is positioned within the spray chamber, the diversion element defining a plurality of flow paths and being movable between a lowered position and a raised position, at least one of the plurality of flow paths directing the flow of wash fluid through the discharge orifice when the diversion element is in the raised position.

DETAILED DESCRIPTION OF THE INVENTION

As used herein, the term “article” may refer to, but need not be limited to dishes, pots, pans, silverware, and other cooking utensils and items that can be cleaned in a dishwashing appliance. The term “wash cycle” is intended to refer to one or more periods of time during which a dishwashing appliance operates while containing the articles to be washed and uses a detergent and water, preferably with agitation, to e.g., remove soil particles including food and other undesirable elements from the articles. The term “rinse cycle” is intended to refer to one or more periods of time during which the dishwashing appliance operates to remove residual soil, detergents, and other undesirable elements that were retained by the articles after completion of the wash cycle. The term “drain cycle” is intended to refer to one or more periods of time during which the dishwashing appliance operates to discharge soiled water from the dishwashing appliance. The term “wash fluid” refers to a liquid used for washing and/or rinsing the articles and is typically made up of water that may include other additives such as detergent or other treatments. Furthermore, as used herein, terms of approximation, such as “approximately,” “substantially,” or “about,” refer to being within a ten percent margin of error.

FIGS. 1 and 2depict an exemplary domestic dishwasher or dishwashing appliance100that may be configured in accordance with aspects of the present disclosure. For the particular embodiment ofFIGS. 1 and 2, the dishwasher100includes a cabinet102(FIG. 2) having a tub104therein that defines a wash chamber106. As shown inFIG. 2, tub104extends between a top107and a bottom108along a vertical direction V, between a pair of side walls110along a lateral direction L, and between a front side111and a rear side112along a transverse direction T. Each of the vertical direction V, lateral direction L, and transverse direction T are mutually perpendicular to one another.

The tub104includes a front opening114and a door116hinged at its bottom for movement between a normally closed vertical position (shown inFIG. 2), wherein the wash chamber106is sealed shut for washing operation, and a horizontal open position for loading and unloading of articles from the dishwasher100. According to exemplary embodiments, dishwasher100further includes a door closure mechanism or assembly118that is used to lock and unlock door116for accessing and sealing wash chamber106.

As best illustrated inFIG. 2, tub side walls110accommodate a plurality of rack assemblies. More specifically, a lower rack assembly120, a middle rack assembly122, and an upper rack assembly124are stacked along the vertical direction V within wash chamber106. Each rack assembly120,122,124is adapted for movement between an extended loading position (not shown) in which the rack is substantially positioned outside the wash chamber106, and a retracted position (shown inFIGS. 1 and 2) in which the rack is located inside the wash chamber106. With respect to middle rack assembly122and upper rack assembly124, this is facilitated, for example, by guide rails126which are mounted to side walls110and rollers128mounted onto rack assemblies122,124, respectively. In addition, lower rack assembly120may include a plurality of carrier roller assemblies130which slidably support lower rack assembly120, thereby permitting the lower rack to roll out of wash chamber106and rest on door116when it is in the open (i.e., horizontal) position.

Some or all of the rack assemblies120,122,124are fabricated into lattice structures including a plurality of wires or elongated members132(for clarity of illustration, not all elongated members making up rack assemblies120,122,124are shown inFIG. 2). In this regard, rack assemblies120,122,124are generally configured for supporting articles within wash chamber106while allowing a flow of wash fluid to reach and impinge on those articles, e.g., during a cleaning or rinsing cycle. According to another exemplary embodiment, a silverware basket (not shown) may be removably attached to a rack assembly, e.g., lower rack assembly120, for placement of silverware, utensils, and the like, that are otherwise too small to be accommodated by rack120.

Dishwasher100further includes a plurality of spray assemblies for urging a flow of water or wash fluid onto the articles placed within wash chamber106. More specifically, as illustrated inFIG. 2, dishwasher100includes a lower spray arm assembly134disposed in a lower region136of wash chamber106and above a sump138so as to rotate in relatively close proximity to lower rack assembly120. Similarly, a mid-level spray arm assembly140is located in an upper region of wash chamber106and may be located below and in close proximity to middle rack assembly122. In this regard, mid-level spray arm assembly140may generally be configured for urging a flow of wash fluid up through middle rack assembly122and upper rack assembly124. Additionally, an upper spray assembly142may be located above upper rack assembly124along the vertical direction V. In this manner, upper spray assembly142may be configured for urging and/or cascading a flow of wash fluid downward over rack assemblies120,122, and124. As further illustrated inFIG. 2, upper rack assembly124may further define an integral spray manifold144, which is generally configured for urging a flow of wash fluid substantially upward along the vertical direction V through upper rack assembly124.

The various spray assemblies and manifolds described herein may be part of a fluid distribution system or fluid circulation assembly150for circulating water and wash fluid in the tub104. More specifically, fluid circulation assembly150includes a pump152for circulating water and wash fluid (e.g., detergent, water, and/or rinse aid) in the tub104. Pump152may be located within sump138or within a machinery compartment located below sump138of tub104, as generally recognized in the art. Fluid circulation assembly150may include one or more fluid conduits or circulation piping for directing water and/or wash fluid from pump152to the various spray assemblies and manifolds. For example, as illustrated inFIG. 2, a primary supply conduit154may extend from pump152, along rear112of tub104along the vertical direction V to supply wash fluid throughout wash chamber106.

As illustrated, primary supply conduit154is used to supply wash fluid to one or more spray assemblies, e.g., to mid-level spray arm assembly140and upper spray assembly142. However, it should be appreciated that according to alternative embodiments, any other suitable plumbing configuration may be used to supply wash fluid throughout the various spray manifolds and assemblies described herein. For example, according to another exemplary embodiment, primary supply conduit154could be used to provide wash fluid to mid-level spray arm assembly140and a dedicated secondary supply conduit (not shown) could be utilized to provide wash fluid to upper spray assembly142. Other plumbing configurations may be used for providing wash fluid to the various spray devices and manifolds at any location within dishwasher appliance100.

Each spray arm assembly134,140,142, integral spray manifold144, or other spray device may include an arrangement of discharge ports or orifices for directing wash fluid received from pump152onto dishes or other articles located in wash chamber106. The arrangement of the discharge ports, also referred to as jets, apertures, or orifices, may provide a rotational force by virtue of wash fluid flowing through the discharge ports. Alternatively, spray arm assemblies134,140,142may be motor-driven, or may operate using any other suitable drive mechanism. Spray manifolds and assemblies may also be stationary. The resultant movement of the spray arm assemblies134,140,142and the spray from fixed manifolds provides coverage of dishes and other dishwasher contents with a washing spray. Other configurations of spray assemblies may be used as well. For example, dishwasher100may have additional spray assemblies for cleaning silverware, for scouring casserole dishes, for spraying pots and pans, for cleaning bottles, etc. One skilled in the art will appreciate that the embodiments discussed herein are used for the purpose of explanation only, and are not limitations of the present subject matter.

In operation, pump152draws wash fluid in from sump138and pumps it to a diverter assembly156, e.g., which is positioned within sump138of dishwasher appliance. Diverter assembly156may include a diverter disk (not shown) disposed within a diverter chamber158for selectively distributing the wash fluid to the spray arm assemblies134,140,142and/or other spray manifolds or devices. For example, the diverter disk may have a plurality of apertures that are configured to align with one or more outlet ports (not shown) at the top of diverter chamber158. In this manner, the diverter disk may be selectively rotated to provide wash fluid to the desired spray device.

According to an exemplary embodiment, diverter assembly156is configured for selectively distributing the flow of wash fluid from pump152to various fluid supply conduits, only some of which are illustrated inFIG. 2for clarity. More specifically, diverter assembly156may include four outlet ports (not shown) for supplying wash fluid to a first conduit for rotating lower spray arm assembly134, a second conduit for rotating mid-level spray arm assembly140, a third conduit for spraying upper spray assembly142, and a fourth conduit for spraying an auxiliary rack such as the silverware rack.

The dishwasher100is further equipped with a controller160to regulate operation of the dishwasher100. The controller160may include one or more memory devices and one or more microprocessors, such as general or special purpose microprocessors operable to execute programming instructions or micro-control code associated with a cleaning cycle. The memory may represent random access memory such as DRAM, or read only memory such as ROM or FLASH. In one embodiment, the processor executes programming instructions stored in memory. The memory may be a separate component from the processor or may be included onboard within the processor. Alternatively, controller160may be constructed without using a microprocessor, e.g., using a combination of discrete analog and/or digital logic circuitry (such as switches, amplifiers, integrators, comparators, flip-flops, AND gates, and the like) to perform control functionality instead of relying upon software.

The controller160may be positioned in a variety of locations throughout dishwasher100. In the illustrated embodiment, the controller160may be located within a control panel area162of door116as shown inFIGS. 1 and 2. In such an embodiment, input/output (“I/O”) signals may be routed between the control system and various operational components of dishwasher100along wiring harnesses that may be routed through the bottom of door116. Typically, the controller160includes a user interface panel/controls164through which a user may select various operational features and modes and monitor progress of the dishwasher100. In one embodiment, the user interface164may represent a general purpose I/O (“GPIO”) device or functional block. In one embodiment, the user interface164may include input components, such as one or more of a variety of electrical, mechanical or electro-mechanical input devices including rotary dials, push buttons, and touch pads. The user interface164may include a display component, such as a digital or analog display device designed to provide operational feedback to a user. The user interface164may be in communication with the controller160via one or more signal lines or shared communication busses.

It should be appreciated that the invention is not limited to any particular style, model, or configuration of dishwasher100. The exemplary embodiment depicted inFIGS. 1 and 2is for illustrative purposes only. For example, different locations may be provided for user interface164, different configurations may be provided for rack assemblies120,122,124, different spray arm assemblies134,140,142and spray manifold configurations may be used, and other differences may be applied while remaining within the scope of the present subject matter.

Referring now generally toFIGS. 3 through 8, a spray nozzle200will be described according to an exemplary embodiment of the present subject matter. Spray nozzle200may be used in dishwashing appliance100or in any other suitable dishwasher or cleaning appliance. For example, spray nozzle200may be incorporated into spray arm assemblies134,140,142, or into integral spray manifold144to provide more even spray coverage. Indeed, although spray nozzle200is illustrated as a standalone assembly inFIGS. 3 through 6, it should be appreciated that spray nozzle could be incorporated into any suitable spray arm or device. The exemplary embodiments described herein are not intended to limit the scope of the present subject matter in any manner.

Referring specifically toFIG. 3, a plurality of spray nozzles200may be spaced apart along a spray arm202. Spray arm202may be a stationary, translating, or rotating arm positioned within wash chamber106. Spray arm202defines an inlet204which may be coupled to a fluid supply, e.g., such as fluid circulation assembly150by primary supply conduit154. In this manner, spray arm202may receive a flow of wash fluid through the inlet204which may be distributed to the plurality of spray nozzles200through a distribution conduit206. According to the illustrated embodiment, spray arm202is configured for fixed mounting (e.g., via mounting clips208) adjacent a silverware or bottle cleaning rack (not shown) within wash chamber106. However, according to alternative embodiments, spray arm202may be positioned at any other suitable location and may include any other suitable number and configuration of spray nozzles200. The exemplary embodiment illustrated herein is intended only for the purpose of describing aspects of the present subject matter, and is not intended to be limiting.

Referring now specifically toFIGS. 4 through 6, spray nozzle200will be described in more detail according to an exemplary embodiment of the present subject matter. As illustrated spray nozzle200includes a housing210that defines a spray chamber212which is in fluid communication with fluid circulation assembly150. In addition, housing210defines a discharge orifice214through which wash fluid is directed onto articles within wash chamber106. More specifically, according to the illustrated embodiment, housing210includes a lower housing216and an upper housing218which are joined together to define spray chamber212therebetween. Lower housing216further defines a chamber inlet220for receiving the flow of wash fluid.

Thus, the flow of wash fluid is received through the single chamber inlet220and flows through spray chamber212to the single discharge orifice214which is configured for discharging and directing the flow of wash fluid onto articles to be cleaned. Continuing the example described with respect toFIG. 3, fluid circulation assembly150may provide a flow of wash fluid which is directed through primary supply conduit154, into spray arm inlet204, along distribution conduit206, and into spray chamber212via chamber inlet220. Notably, in order to improve spray coverage, spray nozzle200may further include a diversion element230which is positioned within spray chamber212and is configured for randomly redirecting the flow of wash fluid out of spray nozzle200.

Diversion element230generally defines a plurality of flow paths232and is movable between a lowered position (not shown) and a raised position (FIG. 5) within spray chamber212. Specifically, diversion element230may be configured for falling toward the lowered position when the flow of wash fluid is off and may be urged towards the raised positioned under the force of the flow of wash fluid during a wash or rinse cycle. In this manner, fluid circulation assembly150may be selectively operated to move diversion element230between the lowered and raised position. Notably, every time diversion element230is moved from the lowered position to the raised position, it is randomly oriented and reseated against discharge orifice214. In this manner, one or more of the plurality of flow paths232may direct the flow of wash fluid out a discharge orifice214in a different direction or orientation corresponding to the orientation of diversion element230.

Referring briefly toFIG. 7, an exemplary embodiment of diversion element230is illustrated. As shown, diversion element230is a substantially spherical component with various features (e.g., flow paths232) defined therein. Specifically, as shown inFIG. 7, the plurality of flow paths232are elongated recesses234defined around a periphery236of diversion element230. The depth and width of elongated recesses234may be designed to produce the desired spray patterns and achieve the desired impingement force.

Although only two circumferentially extending recesses234are illustrated herein, it should be appreciated that any suitable number, size, and direction of recesses234made be defined according to alternative embodiments. In this manner, as best shown inFIGS. 4 and 5, when diversion element230is urged towards the raised position, one or more of elongated recesses234provide a flow path from spray chamber212through discharge orifice214. Notably, as explained above, every time diversion element230seats into discharge orifice214, elongated recesses234direct the flow of wash fluid in a different spray pattern and direction for improved cleaning.

Referring briefly toFIG. 8, another exemplary embodiment of diversion element230is illustrated. Similar to the embodiment described above, diversion element230is a substantially spherical component. However, as shown inFIG. 8, the plurality of flow paths232are internal passageways240defined through an interior242of diversion element230. According to an exemplary embodiment, diversion element230may have a thin outer wall244and may be substantially hollow, e.g., similar to a ping-pong ball. Alternatively, diversion element230may be substantially solid with internal passageways240meeting proximate a center of diversion element230. According still other embodiments, internal passageways240may each be completely independent of other passageways and may be routed through diversion element230in any suitable path or direction.

It should be appreciated that any suitable number, size, and direction of internal passageways240may be defined according to alternative embodiments. In this manner, when diversion element230is urged towards the raised position, one or more of internal passageways240provide a flow path from spray chamber212through discharge orifice214. Notably, as explained above, the direction and orientation of internal passageways240opening through discharge orifice214changes every time diversion element230is seated, thereby creating a unique and improved spray pattern.

Notably, in order to facilitate the movement of diversion element230within spray chamber212, diversion element230must generally have smaller dimensions than spray chamber212, e.g., to prevent binding as diversion element230moves between the lowered and raised position. Therefore, according to the exemplary illustrated embodiment, spray chamber212defines a chamber width250and diversion element230defines an element diameter252. According to the illustrated embodiment, chamber width250is greater than element diameter252. Moreover, as best illustrated inFIG. 5, spray chamber212has tapered side walls254such that chamber width250is greater toward the bottom of spray nozzle200, e.g., toward chamber inlet220.

In addition, according to the illustrated embodiment spray chamber212defines a chamber height256. According to an exemplary embodiment, chamber height256is greater than element diameter252of diversion element230. According to the illustrated embodiment, chamber height256is greater than or equal to two times element diameter252, although other dimensional differences are possible and within the scope of the present subject matter. In this manner, diversion element230may move about freely within spray chamber212. Notably, however, by tapering side walls254, diversion element230may be consistently seated over discharge orifice214when moved toward the raised position.

Notably, it is important that diversion element230is retained within spray chamber212throughout operation of spray nozzle200. Therefore, spray nozzle200may include various features for retaining diversion element230within spray chamber212. For example, according to the illustrated embodiment, diversion element230is substantially spherical and has element diameter252. Thus, according to an exemplary embodiment, chamber inlet220may define an inlet diameter260that is smaller than element diameter252such that diversion element230may not fall out of spray nozzle200, e.g., back into distribution conduit206. Similarly, discharge orifice214may define an orifice diameter262which is also smaller than element diameter252.

According still another embodiment, spray nozzle200may include a retention element270that is positioned within spray chamber212below diversion element230for retaining diversion element230within spray chamber212. In general, retention element270may be any feature or component that extends into spray chamber212and that permits the flow of wash fluid while restricting diversion element230from moving below retention element270. For example, according to the illustrated embodiment, retention element270is a five-armed cross member positioned over chamber inlet220. However, it should be appreciated that according to alternative embodiments, retention element270may be a single cross bar within spray chamber212, a mesh screen, or any other suitable retaining feature.

Although chamber inlet220and discharge orifice214are illustrated and described herein as having a substantially circular cross section, it should be appreciated that according to alternative embodiments, chamber inlet220and discharge orifice214may have any other suitable size and shape. For example, discharge orifice214could instead be an elongated slot defined in upper housing218. Similarly, although diversion element230is illustrated as being substantially spherical, it could have any other suitable shape, size, and flow paths232according to alternative embodiments. The exemplary embodiment of spray nozzle200described herein is not intended to limit the scope of the present subject matter.