Abstract:
A fluid filtration assembly for a dishwasher system is described. The dishwasher system includes a tub defining a wash chamber configured to receive dishwasher contents. The fluid filtration assembly includes a filter assembly having a filter material, a filter fluid inlet, and a filter fluid outlet. The filter fluid inlet is in flow communication with the wash chamber and the filter material. The filter assembly further includes a cleaning fluid inlet that is configured to backflush the filter material. The filter fluid outlet is in flow communication with both the cleaning fluid inlet and the filter fluid inlet. The fluid filtration assembly further includes a valve assembly in flow communication with the cleaning fluid inlet through a first flow path.

Description:
FIELD OF THE INVENTION 
     The present disclosure relates to a water inlet flush for a dishwasher filter. 
     BACKGROUND OF THE INVENTION 
     Conventional dishwasher systems include a main pump assembly and a drain pump assembly for circulating and draining wash fluid, respectively, within a wash chamber defined within the dishwasher system. The main pump assembly feeds wash fluid to various spray arm assemblies for distribution throughout the wash chamber to wash soiled items loaded into dishwasher racks positioned within the wash chamber. Wash fluid sprayed onto the dishwasher items is collected in a sump located in a lower portion of the wash chamber, and water entering the sump is filtered through one or more coarse filters to remove soil and/or sediment from the wash fluid. At least some conventional dishwasher systems further include a filter system in flow communication with the main pump assembly to remove soil and/or sediment of a smaller particle size than those particles filtered by the coarse filters. The main pump assembly draws wash fluid from the sump to re-circulate in the wash chamber, and the coarse and fine filters are used to continuously filter the water in the sump during the re-circulation process. 
     Such filter systems require periodic removal for cleaning by a consumer in which consumers are expected to remove, clean, and properly reinstall filter components on a regular basis. Unfortunately, problems can occur when consumers fail to maintain filter components on a regular basis. For example, dishwasher performance can be degraded by the presence of excess debris which can obstruct water flow. 
     Accordingly, a dishwasher filter assembly that decreases the need for consumer interaction would be desirable. A water inlet that is capable of purging a filter assembly while also providing additional functionality would be particularly useful. 
     BRIEF DESCRIPTION OF THE INVENTION 
     Aspects and advantages of the disclosure will be set forth in part in the following description, or may be obvious from the description, or may be learned through practice of the disclosure. 
     In certain embodiments of the present disclosure, a fluid filtration assembly for a dishwasher system is described. The dishwasher system includes a tub defining a wash chamber configured to receive dishwasher contents. The fluid filtration assembly includes a filter assembly having a filter material, a filter fluid inlet, and a filter fluid outlet. The filter fluid inlet is in flow communication with the wash chamber and the filter material. The filter assembly further includes a cleaning fluid inlet that is configured to backflush the filter material. The filter fluid outlet is in flow communication with both the cleaning fluid inlet and the filter fluid inlet. The fluid filtration assembly further includes a valve assembly in flow communication with the cleaning fluid inlet through a first flow path. 
     In yet other embodiments of the present disclosure, a dishwasher is described. The dishwasher includes a tub defining a wash chamber configured to receive dishwasher contents. The dishwasher further includes a fluid filtration assembly. The fluid filtration assembly includes a filter assembly having a filter material, a filter fluid inlet, and a filter fluid outlet. The filter fluid inlet is in flow communication with the wash chamber and the filter material. The filter assembly further includes a cleaning fluid inlet that is configured to backflush the filter material. The filter fluid outlet is in flow communication with both the cleaning fluid inlet and the filter fluid inlet. The fluid filtration assembly further includes a valve assembly in flow communication with the cleaning fluid inlet through a first flow path. 
     These and other features, aspects and advantages of the present disclosure will become better understood with reference to the following description and appended claims. The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and, together with the description, serve to explain the principles of the invention. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       A full and enabling disclosure, including the best mode thereof, directed to one of ordinary skill in the art, is set forth in the specification, which makes reference to the appended figures, in which: 
         FIG. 1  provides a side elevation view of an example dishwasher system partially broken away in accordance with certain aspects of the present disclosure. 
         FIG. 2  is a top plan view of a portion of the dishwasher system shown in  FIG. 1  along line  2 - 2  in accordance with certain aspects of the present disclosure. 
         FIG. 3  is a partial side elevation view of the portion of the dishwasher system shown in  FIG. 2  in accordance with certain aspects of the present disclosure. 
         FIG. 4  is a cross sectional schematic view of the portion of the dishwasher system shown in  FIG. 3  along line  44  in accordance with certain aspects of the present disclosure. 
         FIG. 5  illustrates a valve in accordance with certain aspects of the present disclosure. 
         FIG. 6  illustrates a filter assembly in accordance with certain aspects of the present disclosure. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     The present disclosure relates to a water inlet flush for a dishwasher filter. Utilization of such a water inlet decreases the need for consumer interaction and can allow for a more efficient draining operation. Advantageously, the water inlet of the present disclosure is also capable of providing additional functionality, such as a dedicated silverware spray. Reference now will be made in detail to embodiments of the invention, one or more examples of which are illustrated in the drawings. Each example is provided by way of explanation of the invention, not limitation of the invention. In fact, it will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the scope or spirit of the invention. For instance, features illustrated or described as part of one embodiment can be used with another embodiment to yield a still further embodiment. Thus, it is intended that the present invention covers such modifications and variations as come within the scope of the appended claims and their equivalents. 
       FIG. 1  is a side elevation view of an example domestic dishwasher system  100  partially broken away. The flow control mechanism described herein may be practiced in other types of dishwashers and dishwasher systems other than just dishwasher system  100 . Accordingly, the following description is for illustrative purposes only, and the flow control is not limited to use in a particular type of dishwasher system, such as dishwasher system  100 . 
     Dishwasher  100  includes a cabinet  102  having a tub  104  therein and forming a wash chamber  106 . Tub  104  includes a front opening (not shown in  FIG. 1 ) and a door  120  hinged at its bottom  122  for movement between a normally closed vertical position (shown in  FIG. 1 ) wherein wash chamber is sealed shut for washing operation, and a horizontal open position (not shown) for loading and unloading of dishwasher contents. 
     Upper and lower guide rails  124 ,  126  are mounted on tub side walls  128  and accommodate upper and lower roller-equipped racks  130 ,  132 , respectively. Each of upper and lower racks  130 ,  132  is fabricated from known materials into lattice structures including a plurality of elongate members  134 , and each rack  130 ,  132  is adapted for movement between an extended loading position (not shown) in which at least a portion of the rack is positioned outside wash chamber  106 , and a retracted position (shown in  FIG. 1 ) in which the rack is located inside wash chamber  106 . Conventionally, a silverware basket (not shown) is removably attached to lower rack  132  for placement of silverware, utensils, and the like that are too small to be accommodated by upper and lower racks  130 ,  132 . 
     A control input selector  136  is mounted at a convenient location on an outer face  138  of door  120  and is coupled to known control circuitry (not shown) and control mechanisms (not shown) for operating a fluid circulation assembly (not shown in  FIG. 1 ) for circulating water and dishwasher fluid in dishwasher tub  104 . In one embodiment, the fluid circulation assembly includes at least one washing water directing device, such as, for example, a spray arm. The fluid circulation assembly is located in a machinery compartment  140  located below a bottom sump portion  142  of tub  104 , and its construction and operation is explained in detail below. 
     A lower spray-arm-assembly  144  is rotatably mounted within a lower region  146  of wash chamber  106  and above tub sump portion  142  so as to rotate in relatively close proximity to lower rack  132 . A mid-level spray-arm assembly  148  is located in an upper region of wash chamber  106  in close proximity to upper rack  130  and at a sufficient height above lower rack  132  to accommodate items such as a dish or platter (not shown) that is expected to be placed in lower rack  132 . In a further embodiment, an upper spray arm assembly (not shown) is located above upper rack  130  at a sufficient height to accommodate a tallest item expected to be placed in upper rack  130 , such as a glass (not shown) of a selected height. 
     Lower and mid-level spray-arm assemblies  144 ,  148  and the upper spray arm assembly are fed by the fluid circulation assembly, and each spray-arm assembly includes an arrangement of discharge ports or orifices for directing washing liquid onto dishes located in upper and lower racks  130 ,  132 , respectively. The arrangement of the discharge ports in at least lower spray-arm assembly  144  results in a rotational force as washing fluid flows through the discharge ports. The resultant rotation of lower spray-arm assembly  144  provides coverage of dishes and other dishwasher contents with a washing spray. In various alternative embodiments, mid-level spray arm  148  and/or the upper spray arm are also rotatably mounted and configured to generate a swirling spray pattern above and below upper rack  130  when the fluid circulation assembly is activated. 
       FIG. 2  is a top plan view of a dishwasher system  100  just above lower spray arm assembly  144 . Tub  104  is generally downwardly sloped beneath lower spray arm assembly  144  toward tub sump portion  142 , and tub sump portion is generally downwardly sloped toward a sump  150  in flow communication with the fluid circulation assembly (not shown in  FIG. 2 ). Tub sump portion  142  includes a six-sided outer perimeter  152 . Lower spray arm assembly is substantially centered within tub  104  and wash chamber  106 , off-centered with respect to tub sump portion  142 , and positioned above tub  104  and tub sump portion  142  to facilitate free rotation of spray arm  144 . 
     Tub  104  and tub sump portion  142  are downwardly sloped toward sump  150  so that water sprayed from lower spray arm assembly  144 , mid-level spray arm assembly  148  (shown in  FIG. 1 ) and the upper spray arm assembly (not shown) is collected in tub sump portion  142  and directed toward sump  150  for filtering and re-circulation during a dishwasher system wash cycle. In addition, a conduit  154  extends beneath lower spray arm assembly  144  and is in flow communication with the fluid circulation assembly. Conduit  154  extends to a back wall  156  of wash chamber  106 , and upward along back wall  156  for feeding wash fluid to mid-level spray arm assembly  148  and the upper spray arm assembly. 
       FIG. 3  illustrates fluid circulation assembly  170  located below wash chamber  106  (shown in  FIGS. 1 and 2 ) in machinery compartment  140  (shown in phantom in  FIG. 3 ). Fluid circulation assembly  170  includes a main pump assembly  172 . Main pump assembly is in flow communication with inlet flow from water valve  200  which purges filter assembly  190  as is further described herein. Importantly, inlet flow can serve the dual purpose of backflushing the filter assembly  190  while also feeding the dishwasher for the cleaning cycle. Drain pump assembly  174  is in fluid communication with sump  150  (shown in  FIG. 2 ) and a building plumbing system drain pipe  204 . While not described in detail herein, flow communication can be provided by hoses, pipes, tubes, or the like as would be understood in the art. 
       FIG. 4  is a cross sectional schematic view of dishwasher system  100 , and more specifically of fluid circulating assembly  170  through drain pump assembly  174 . Tub  104  is downwardly sloped toward tub sump portion  142 , and tub sump portion is downwardly sloped toward sump  150 . As wash fluid is pumped through lower spray arm assembly  144 , and further delivered to mid-level spray arm assembly  148  (shown in  FIG. 1 ) and the upper spray arm assembly (not shown), washing sprays are generated in wash chamber  106 , and wash fluid collects in sump  150 . 
     A filter assembly  190  is located in flow communication with sump  150  such as within sump  150  adjacent to tub sump portion  142 . As wash fluid is pumped into lower spray arm  144  to generate a washing spray in wash chamber  106 , wash fluid drains into filter assembly  190  to filter wash fluid sediment and particles before flowing into sump  150  over tub sump portion  142 . 
     A drain check valve  186  is established in flow communication with sump  150  and opens or closes flow communication between sump  150  and a drain pump inlet  188 . A drain pump  189  is in flow communication with drain pump inlet  188  and includes an electric motor for pumping fluid at inlet  188  to a pump discharge (not shown in  FIG. 4 ) and ultimately to a building plumbing system drain (not shown). When drain pump  189  is energized, a negative pressure is created in drain pump inlet  188  and drain check valve  186  is opened, allowing fluid in sump  150  to flow into fluid pump inlet  188  and be discharged from fluid circulation assembly  170 . 
     Referring to  FIG. 6 , a filter assembly  190  in accordance with the present disclosure is illustrated. Filter assembly  190  can include a cover  180  and screen  210  that are generally circular to prevent larger objects from entering sump  150 , such as a piece of silverware or another dishwasher item that is dropped beneath lower rack  132  (shown in  FIG. 1 ). Cover  190  can include handle  214  which allows filter assembly  190  to be removed from dishwasher for cleaning. Main body portion  212  has a generally cylindrical shape to aid in channeling the flow of washing fluid across one or more filter screens. In this regard, main body portion  212  can include an outer perimeter coarse filter  208  to filter larger wash fluid sediment and an inner fine filter  206  to filter smaller wash sediment. 
     During normal operation, wash fluid flows through filter screen  210  into sump  150  and larger food particles from dishes or silverware collect on filter screen  210 . Wash fluid is further filtered by coarse filter  208  and fine filter  206  before arriving in sump  150 . Filter assembly  190  can be seated in or around sump  150  using any suitable method as would be known in the art such as twist lock or the like so as to allow easy user removal of filter assembly or parts thereof and reinsertion of same. 
     In accordance with the present disclosure, inlet flow from water valve  200  can be utilized to purge filter assembly  190  and minimize user removal and service of filter assembly  190 . After passing through filter assembly  190 , inlet flow can be utilized to fill dishwasher with water for the cleaning cycle. In this regard, inlet water from a building plumbing system water supply pipe  202  can be split between filter assembly  190  and a separate flow line that can supply one or more sprayers in wash chamber  106  as will be described in more detail herein. For instance, referring to  FIG. 5 , in certain embodiments of the present disclosure, a y valve can be utilized to direct inlet flow to filter assembly  190 . The Y-valve can include an inlet  216  and two outlets  218 ,  220  adapted to route fluid entering the inlet  216  into the outlets  218 ,  220  at varying routing ratios as desired. In this manner, flow can be diverted to sprayer(s) without disrupting normal dishwasher operation which receives water flow through filter assembly  190 . Water flow to filter assembly  190  can be routed to within filter assembly  190  to backflush filter assembly  190  and clean lodged debris or sediment that can impede fluid flow. 
     In addition to a y valve, any other suitable water valves are contemplated for use in connection with the present disclosure. For example, valve  200  can be include an actuated valve, such as a solenoid valve, which can send water flow to filter assembly  190  intermittently based on water needs for dishwashing. Such a solenoid valve can be actuated as would be understood in the art by a controller or the like. 
     In addition to water flow for filter assembly  190 , as described previously, water from water valve  200  can also be routed to one or more dedicated sprayers  222  within dishwasher. Sprayer(s)  222  can be of any suitable form as would be known in the art. Flow can be split from the flow paths created by valve  200  to include such sprayer(s). Alternatively, flow can be split by additional valve  220  (illustrated in  FIG. 4 ) to such sprayer(s). Again, any suitable water valve for such purpose is contemplated for use in connection with the present disclosure. For example, additional valve  220  can be include an actuated valve, such as a solenoid valve as described above, which can send water flow to filter assembly  190  and sprayer(s)  222  intermittently. In certain embodiments, water flow from water valve  200  can be direct to sprayers  222 . 
     In certain embodiments, sprayer(s) can be positioned adjacent to one or more silverware baskets to spray silverware with clean water. 
     This written description uses examples to disclose the invention, including the best mode, and also to enable any person skilled in the art to practice the invention, including making and using any devices or systems and performing any incorporated methods. The patentable scope of the invention is defined by the claims, and may include other examples that occur to those skilled in the art. Such other examples are intended to be within the scope of the claims if they include structural elements that do not differ from the literal language of the claims, or if they include equivalent structural elements with insubstantial differences from the literal languages of the claims.