Patent Publication Number: US-9402526-B2

Title: Dishwasher with spray system

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application claims the benefit of U.S. Provisional Patent Application No. 61/537,595, filed Sep. 22, 2011, which is incorporated herein by reference in its entirety. 
    
    
     BACKGROUND OF THE INVENTION 
     Contemporary automatic dishwashers for use in a typical household include a tub and at least one rack or basket for supporting soiled utensils within the tub. A spraying system may be provided for recirculating liquid throughout the tub to remove soils from the utensils. The spraying system may include various sprayers including a rotatable spray arm. 
     SUMMARY 
     An embodiment of the invention relates to a dishwasher having a tub at least partially defining a treating chamber and a spraying system for supplying liquid to the treating chamber. The spraying system includes a rotatable spray arm having a body with an interior, a liquid passage provided in the interior, and a plurality of outlets extending through the body and in fluid communication with the liquid passage. The dishwasher also includes a valve body fluidly coupling the plurality of outlets to the liquid passage and moveable between at least two positions and an actuator operably coupled to the valve body and moving the valve body between the at least two positions based on the rotation of the rotatable spray arm. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       In the drawings: 
         FIG. 1  is a schematic view of a dishwasher with a spray system according to a first embodiment of the invention. 
         FIG. 2  is a cross-sectional view of a rotatable spray arm of the spray system of the dishwasher of  FIG. 1  and illustrating a valve body for the rotatable spray arm. 
         FIGS. 3A-3C  are schematic views of the valve body in various positions within the rotatable spray arm of  FIG. 2 . 
         FIG. 4  is a cross-sectional view of a second embodiment of a lower spray arm, which may be used in the dishwasher of  FIG. 1 . 
         FIG. 5  is a cross-sectional view of a third embodiment of a lower spray arm, which may be used in the dishwasher of  FIG. 1 . 
         FIGS. 6A-6B  are cross-sectional views of a valve body in various positions within the rotatable spray arm of  FIG. 5 . 
         FIG. 7 . is a schematic exploded view of a fourth embodiment of a lower spray arm, which may be used in the dishwasher of  FIG. 1 . 
         FIG. 8 . is a schematic top view of the lower spray arm of  FIG. 7  with a valve body in a first position. 
         FIG. 9 . is a schematic top view of the lower spray arm of  FIG. 7  with the valve body in a second position. 
         FIG. 10 . is a schematic top view of the lower spray arm of  FIG. 7  with the valve body in a third position. 
     
    
    
     DESCRIPTION OF EMBODIMENTS OF THE INVENTION 
     Referring to  FIG. 1 , a first embodiment of the invention is illustrated as an automatic dishwasher  10  having a cabinet  12  defining an interior. Depending on whether the dishwasher  10  is a stand-alone or built-in, the cabinet  12  may be a chassis/frame with or without panels attached, respectively. The dishwasher  10  shares many features of a conventional automatic dishwasher, which will not be described in detail herein except as necessary for a complete understanding of the invention. While the present invention is described in terms of a conventional dishwashing unit, it could also be implemented in other types of dishwashing units, such as in-sink dishwashers, multi-tub dishwashers, or drawer-type dishwashers. 
     A controller  14  may be located within the cabinet  12  and may be operably coupled with various components of the dishwasher  10  to implement one or more cycles of operation. A control panel or user interface  16  may be provided on the dishwasher  10  and coupled with the controller  14 . The user interface  16  may 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  14  and receive information. 
     A tub  18  is located within the cabinet  12  and at least partially defines a treating chamber  20  with an access opening in the form of an open face. A cover, illustrated as a door  22 , may be hingedly mounted to the cabinet  12  and may move between an opened position, wherein the user may access the treating chamber  20 , and a closed position, as shown in  FIG. 1 , wherein the door  22  covers or closes the open face of the treating chamber  20 . 
     Utensil holders in the form of upper and lower racks  24 ,  26  are located within the treating chamber  20  and receive utensils for being treated. The racks  24 ,  26  are mounted for slidable movement in and out of the treating chamber  20  for ease of loading and unloading. As used in this description, the term “utensil(s)” is intended to be generic to any item, single or plural, that may be treated in the dishwasher  10 , including, without limitation; dishes, plates, pots, bowls, pans, glassware, and silverware. While not shown, additional utensil holders, such as a silverware basket on the interior of the door  22 , may also be provided. 
     A spraying system  28  may be provided for spraying liquid into the treating chamber  20  and is illustrated in the form of an upper sprayer  30 , a mid-level sprayer  32 , a lower rotatable spray arm  34 , and a spray manifold  36 . The upper sprayer  30  may be located above the upper rack  24  and is illustrated as a fixed spray nozzle that sprays liquid downwardly within the treating chamber  20 . Mid-level rotatable sprayer  32  and lower rotatable spray arm  34  are located, respectively, beneath upper rack  24  and lower rack  26  and are illustrated as rotating spray arms. The mid-level spray arm  32  may provide a liquid spray upwardly through the bottom of the upper rack  24 . The lower rotatable spray arm  34  may provide a liquid spray upwardly through the bottom of the lower rack  26 . The mid-level rotatable sprayer  32  may optionally also provide a liquid spray downwardly onto the lower rack  26 , but for purposes of simplification, this will not be illustrated herein. 
     The spray manifold  36  may be fixedly mounted to the tub  18  adjacent to the lower rack  26  and may provide a liquid spray laterally through a side of the lower rack  26 . The spray manifold  36  may not be limited to this position; rather, the spray manifold  36  may be located in virtually any part of the treating chamber  20 . While not illustrated herein, the spray manifold  36  may include multiple spray nozzles having apertures configured to spray wash liquid towards the lower rack  26 . The spray nozzles may be fixed or rotatable with respect to the tub  18 . Suitable spray manifolds are set forth in detail in U.S. Pat. No. 7,445,013, filed Jun. 17, 2003, and titled “Multiple Wash Zone Dishwasher,” and U.S. Pat. No. 7,523,758, filed Dec. 30, 2004, and titled “Dishwasher Having Rotating Zone Wash Sprayer,” both of which are incorporated herein by reference in their entirety. 
     A liquid recirculation system may be provided for recirculating liquid from the treating chamber  20  to the spraying system  28 . The recirculation system may include a sump  38  and a pump assembly  40 . The sump  38  collects the liquid sprayed in the treating chamber  20  and may be formed by a sloped or recessed portion of a bottom wall  42  of the tub  18 . The pump assembly  40  may include both a drain pump  44  and a recirculation pump  46 . 
     The drain pump  44  may draw liquid from the sump  38  and pump the liquid out of the dishwasher  10  to a household drain line  48 . The recirculation pump  46  may draw liquid from the sump  38  and pump the liquid to the spraying system  28  to supply liquid into the treating chamber  20 . While the pump assembly  40  is illustrated as having separate drain and recirculation pumps  44 ,  46  in an alternative embodiment, the pump assembly  40  may include a single pump configured to selectively supply wash liquid to either the spraying system  28  or the drain line  48 , such as by configuring the pump to rotate in opposite directions, or by providing a suitable valve system. While not shown, a liquid supply system may include a water supply conduit coupled with a household water supply for supplying water to the sump  38 . 
     As shown herein, the recirculation pump  46  has an outlet conduit  50  in fluid communication with the spraying system  28  for discharging wash liquid from the recirculation pump  46  to the sprayers  30 - 36 . As illustrated, liquid may be supplied to the spray manifold  36 , mid-level rotatable sprayer  32 , and upper sprayer  30  through a supply tube  52  that extends generally rearward from the recirculation pump  46  and upwardly along a rear wall of the tub  18 . While the supply tube  52  ultimately supplies liquid to the spray manifold  36 , mid-level rotatable sprayer  32 , and upper sprayer  30 , it may fluidly communicate with one or more manifold tubes that directly transport liquid to the spray manifold  36 , mid-level rotatable sprayer  32 , and upper sprayer  30 . Further, diverters (not shown) may be provided within the spraying system  28  such that liquid may be selectively supplied to each of the sprayers  30 - 36 . The sprayers  30 - 36  spray water and/or treating chemistry onto the dish racks  24 ,  26  (and hence any utensils positioned thereon) to effect a recirculation of the liquid from the treating chamber  20  to the liquid spraying system  28  to define a recirculation flow path. 
     A heating system having a heater  54  may be located within or near the sump  38  for heating liquid contained in the sump  38 . A filtering system (not shown) may be fluidly coupled with the recirculation flow path for filtering the recirculated liquid. 
       FIG. 2  illustrates a cross-sectional view of the lower rotatable spray arm  34  comprising a body  56  having an interior  58 . A liquid passage  59  may be provided in the interior  58  and fluidly couples with the outlet conduit  50  and recirculation pump  46 . A plurality of outlets  60  extend through the body  56  and may be in fluid communication with the liquid passage  59 . As illustrated, the interior  58  defines the liquid passage  59 . However, a separate liquid passage  59  may be located within the interior  58 . 
     Nozzles, such as nozzles  62  and  64 , may be provided on the body  56  and may be fluidly coupled with the outlets  60 , which lead to the liquid passage  58 . Multiple nozzles  62  and  64  have been illustrated. The multiple nozzles  62  may correlate to a first subset of the plurality of outlets  60  and the multiple nozzles  64  may correlate to a second subset of the plurality of outlets  60 . Nozzles  62  and  64  may provide different spray patterns, although this need not be the case. It is advantageous to do so to provide for different cleaning effects from a single spray arm. The first nozzle  62  may emit a first spray pattern (not shown), which may be a discrete, focused, and concentrated spray, which may provide a higher pressure spray. The second nozzle  64  may emit a second spray pattern (not shown), which may be a wide angle diffused spray pattern that produces more of a shower as compared to the more concentrated and discrete spray pattern produced by the first nozzle  62 . The shower spray may be more suitable for distributing treating chemistry whereas the higher pressure spray may be more suitable for dislodging soils. It has been contemplated that the nozzles  62  and  64  may be arrange differently such that each type of nozzle  62 ,  64  may be included in both the first and second subsets of outlets  60 . 
     A valve body  70  is illustrated as being located within the interior  56  and may be operable to selectively fluidly couple at least some of the plurality of outlets  60  to the liquid passage  59 . More specifically, the valve body  70  has been illustrated as including a slidable plate  72  having multiple openings  74 . The slidable plate  72  may be slidably mounted within the interior  58  of the body  56  of the rotatable spray arm  34  for movement between at least two positions. One position may allow the multiple openings  74  to fluidly couple the first subset of outlets  60  to the liquid passage  59  and the second position may allow the multiple openings  74  to fluidly couple the second subset of outlets  60  to the liquid passage  59 . In this way, the different nozzles  62 ,  64  and/or different spray patterns may be selected with the sliding of the plate  72 . Alternatively, the different subsets of outlets  60  may be located on different portions of the arms such that the selection of a particular subset of outlets  60  controls the location of the spray, regardless of whether the spray pattern is different. For example, one subset of outlets  60  may be located at the ends of the spray arm to direct liquid solely into the hard to reach areas of the treating chamber. 
     An actuator  80  may be operably coupled with the valve body  70  and may move the valve body  70  between the at least two positions based on the rotation of the rotatable spray arm  34 . The actuator  80  may be any suitable mechanism capable of moving the valve body  70  between the at least two positions based on the rotation of the rotatable spray arm  34 . By way of a non-limiting example, the actuator  80  may include a drive system  82  operably coupled with the rotatable spray arm  34  and the valve body  70  such that rotation of the spray arm  34  moves the valve body  70  between the at least two positions. The drive system  82  has been illustrated as including a gear assembly  84  operably coupling the rotatable spray arm  34  and the valve body  70  such that rotation of the rotatable spray arm  34  moves the gear assembly  84  which in turn moves the slidable plate  72  between the at least two positions. Thus, the gear assembly  84  helps convert the rotational motion of the spray arm  34  into sliding motion for the slidable plate  72 . The gear assembly  84  has been illustrated as including a gear chain having a first gear  85 , second gear  86 , third gear  87 , fourth gear  88 , and a fixed gear  89 . A fixed shaft  90  may extend through a portion of the body  56  such that the rotatable spray arm  34  is rotationally mounted on the fixed shaft  90 . Further, the fixed gear  89  may be fixedly mounted on the fixed shaft  90 . 
     The drive system  82  further comprises a pin  92  operably coupled with and extending from an upper portion of the fourth gear  88  and received within a channel  94  located in the valve body  70  to operably couple the gear assembly  84  with the slidable plate  72 . The channel  94  may be a depression in a bottom portion of the slidable plate  72  or as illustrated may be formed between two opposing walls  95 ,  96  extending downwardly from the bottom of the slidable plate  72 . 
     A bracket  97  may be located within the interior  58  and houses at least a portion of the gear assembly  84  to provide support for the gear assembly  84 . Portions of the gear assembly  84  may also be held within supports  98  formed by the body  56  of the spray arm assembly  34 . 
     The operation of the dishwasher  10  with the described spray arm structure will now be described. The user will initially select a cycle of operation via the user interface  16 , with the cycle of operation being implemented by the controller  14  controlling various components of the dishwasher  10  to implement the selected cycle of operation in the treating chamber  20 . Examples of cycles of operation include normal, light/china, heavy/pots and pans, and rinse only. The cycles of operation may include one or more of the following steps: a wash step, a rinse step, and a drying step. The wash step may further include a pre-wash step and a main wash step. The rinse step may also include multiple steps such as one or more additional rinsing steps performed in addition to a first rinsing. During such cycles, wash fluid, such as water and/or treating chemistry (i.e., water and/or detergents, enzymes, surfactants, and other cleaning or conditioning chemistry) passes from the recirculation pump  46  into the spraying system  28  and then exits the spraying system through the sprayers  30 - 36 . 
     The lower rotatable spray arm  34  may rely on liquid pumped from the recirculation pump  46  to provide hydraulic drive to rotate the lower rotatable spray arm  34 , which through the actuator  80  affects the movement of the valve body  70 . More specifically, as illustrated in  FIG. 3A , a hydraulic drive  99  may be formed by an outlet in the body  56  being oriented such that liquid emitted from the hydraulic drive outlet  99  effects the rotation of the lower rotatable spray arm  34 . The lower rotatable spray arm  34  has been illustrated as having two hydraulic drive outlets  99  and these hydraulic drive outlets  99  are located such that when the recirculation pump  46  is activated, the lower rotatable spray arm  34  rotates regardless of the position of the valve body  70 . It has also been contemplated that such hydraulic drive outlets  99  may be located on various portions of the body  56  including a side or bottom portion of the body  56 . Alternatively, one or more of the multiple nozzles  62 ,  64  may form such hydraulic drive outlets. 
     As the lower rotatable spray arm  34  is hydraulically rotated about the fixed shaft  90 , the first gear  85 , which is mounted between the fixed gear  89  and the second gear  86 , is rotatably mounted within the support  98 , and moves with the rotation of the lower rotatable spray arm  34 , may be driven around the fixed gear  89 . Thus, the first gear  85  is also hydraulically driven and may be caused to circle about the fixed gear  89  as the lower rotatable spray arm  34  rotates about the fixed shaft  90 . As the first gear  85  is driven about the fixed gear  89 , it in turn causes the rotation of the second gear  86 , the third gear  87 , and the fourth gear  88 . 
     As the fourth gear  88  rotates, the pin  92  rotates within the interior  58  of the lower rotatable spray arm  34 . As the pin  92  rotates, it moves within the boundaries of the channel  94  and causes the slidable plate  72  to be moved back and forth within the interior  58  of the lower rotatable spray arm  34 . More specifically, as the pin  92  rotates with the fourth gear  88 , the pin  92  pushes on the wall  95  for a first portion of a full rotation of the fourth gear  88  and pushes on the wall  96  for a second portion of the full rotation of the fourth gear  88 . When the pin  92  pushes on the wall  95  it moves the slidable plate  72  to the first position illustrated in  FIG. 3B . The slidable plate  72  may stay in the first position until the pin  92  is rotationally advanced to a point where it begins to push on the wall  96 . When the pin  92  pushes on the wall  96  it moves the slidable plate  72  in the opposite direction until it reaches the second position illustrated in  FIG. 3C . The slidable plate  72  may stay in the second position until the pin  92  is rotationally advanced to a point where it begins to again push on the wall  95 . As the fourth gear  88  continues to rotate, the pin  92  continues to alternatively push against one of the walls  95  and  96  and continues to move the slidable plate  72  into the first and second positions. In this manner, the movement of the pin  92  within the channel  94  operably couples the gear assembly  84  to the slidable plate  72  such that the rotation of the gear assembly  84  may be converted into translational movement of the slidable plate  72 . Essentially, the actuator  80  allows the valve body  70  to move between the at least two positions based on a rotational position of the rotatable spray arm  34 . 
     As the slidable plate  72  moves side to side inside the lower rotatable spray arm  34 , the valve body  70  closes the fluid path to one of the first and second subsets of outlets  60  and opens a fluid path to the other of the first and second subsets of outlets  60 . More specifically, as the slidable plate  72  moves within the lower rotatable spray arm  34 , the multiple openings  74  may align with either the first and second subset of outlets  60 . When the slidable plate  72  is in the first position, the multiple openings  74  are aligned with the first subset of outlets  60  correlating to the multiple nozzles  62  and in the second position the multiple openings  74  are aligned with the second subset of outlets  60  correlating to the multiple nozzles  64 . Thus, as the valve body  70  moves relative to the lower rotatable spray arm  34 , each of the first and second subsets of outlets  60  are sequentially fluidly coupled and uncoupled as the lower rotatable spray arm  34  rotates. 
     It has been contemplated that the valve body  70  may have additional openings or alternative openings such that the second subset of the plurality of outlets which are fluidly coupled with the liquid passage may only differ from the first subset by one of the outlets. It has also been contemplated that when the valve body  70  is located intermediately of the first and second positions, water may be still be sprayed from the plurality of outlets  60  if at least a portion of the multiple openings fluidly couples a portion of the plurality of outlets  60 . It has also been contemplated that the valve body  70  may be shaped such that there may be a point where the outlets in the valve body  70  do not allow for the fluid to enter any of the plurality of outlets  60  except for the hydraulic drive outlets  99 . 
     The gear chain of the gear assembly  84  is illustrated as forming a reduction gear assembly. That is the valve body  70  is moved between the at least two positions by the actuator  80  over multiple rotations of the lower rotatable spray arm  34 . As illustrated, the reduction gear assembly may provide a 40:1 gear reduction such that the valve body  70  will slide to the first and second positions over forty revolutions of the lower rotatable spray arm  34 . The gear ratios of the gear assembly  84  may be selected to control the relative movement of the valve body  70  to the lower rotatable spray arm  34 . The gear ratio of the gear assembly  84  is a function of the ratios of gears forming the gear assembly  84 . Thus, the gears may be selected to provide a desired ratio to provide a desired fluid coupling time between the fluid passage  59  and the first and second subsets of outlets  60 . The gear reduction ratio may also be selected to aid in allowing the hydraulic drive outlets  99  to overcome the friction created by the valve body  70 . 
     As the rotatable spray arm  34  turns, the valve body  70  continues to move between the first and second positions and continues to selectively fluidly couple the first and second subsets of outlets  60 . The amount of time that the multiple openings  74  are fluidly coupled with each of the first and second subsets of outlets  60  controls the duration of the time that each of the nozzles  62 ,  64  spray liquid. The time of fluid coupling may be thought of as a dwell time. With the above described valve body  70  and actuator  80 , the dwell time may be controlled by the gear ratio, the spacing between the two opposing walls  95 ,  96  extending around the pin  92 , and the flow rate of liquid. The movement of the lower rotatable spray arm  34  and the valve body  70  ends when fluid is no longer pumped by the recirculation pump  46  to the lower rotatable spray arm  34  such that the lower rotatable spray arm  34  is no longer hydraulically driven. 
     It has also been contemplated that a drive system may be included to control the rotation of the lower rotatable spray arm  34 . Such a drive system may be motor-driven. For example, an electric motor (not shown) may be provided externally of the tub  18  and may be operably coupled to a portion of the lower rotatable spray arm  34  to rotate the lower rotatable spray arm  34 . Such a motor-driven spray arm is set forth in detail in U.S. Pat. No. 8,113,222, filed Dec. 16, 2008, and titled “Dishwasher with Driven Spray Arm for Upper Rack” and U.S. Pat. No. 7,980,260, filed Apr. 16, 2010, and titled “Dishwasher with Driven Rotatable Spray Arm,” which are incorporated herein by reference in their entirety. If the lower rotatable spray arm  34  is motor operated, the valve body  70  may be moved as the lower rotatable spray arm  34  rotates regardless of the flow rate provided by the recirculation pump  46 . A motor driven lower rotatable spray arm  34  may be useful in instances where no hydraulic drive outlets are provided. Such a motor driven lower rotatable spray arm  34  may also allow for longer dwell times. In this manner, zonal washing, may be accomplished within the treating chamber  20  because the motor may have the ability to manipulate the speed of rotation of the lower rotatable spray arm  34  such that the controller  14  may control the spray emitted from the multiple nozzles  62  and  64  in pre-selected areas of the treating chamber  20 . 
       FIG. 4  illustrates a cross-sectional view of an alternative lower rotatable spray arm  134  according to a second embodiment of the invention. The lower rotatable spray arm  134  is similar to the lower rotatable spray arm  34  previously described and therefore, like parts will be identified with like numerals increased by 100, with it being understood that the description of the like parts of the lower rotatable spray arm  34  applies to the lower rotatable spray arm  134 , unless otherwise noted. 
     The differences between the lower rotatable spray arm  34  and the lower rotatable spray arm  134  include that the lower rotatable spray arm  134  has been illustrated as having a lower profile body  156 , an alternative gear assembly  184 , and an alternative bracket  197 , which is configured to accommodate the alternative gear assembly  184 . During operation, the lower rotatable spray arm  134 , valve body  170 , and actuator  180  operate much the same as in the first embodiment wherein as the lower rotatable spray arm  134  is rotated, the gears in the gear assembly  184  are driven and the slidable plate  172  is moved between the first and second positions. However, the gear assembly  184  is configured to provide a larger gear reduction, namely a 73:1 gear reduction, such that the valve body  170  will slide to the first and second positions over 73 revolutions of the lower rotatable spray arm  134 . Thus, the dwell time or fluid coupling time between the fluid passage  159  and the first and second subsets of outlets  160  is greater than in the first embodiment. Further, the lower profile body  156  may increase the space available in the treating chamber  20  for holding utensils to be treated. 
       FIG. 5  illustrates a cross-sectional view of an alternative lower rotatable spray arm  234  according to a third embodiment of the invention. The lower rotatable spray arm  234  is similar to the lower rotatable spray arm  34  previously described and therefore, like parts will be identified with like numerals increased by 200, with it being understood that the description of the like parts of the lower rotatable spray arm  34  applies to the lower rotatable spray arm  234 , unless otherwise noted. 
     One difference between the lower rotatable spray arm  34  and the lower rotatable spray arm  234  is that the plurality of outlets  260  form the nozzles for the spray arm  234  and no additional nozzle structures are provided on the body  256 . Further, each of the outlets  260  is illustrated as having an identical configuration, such that there are no first and second subsets of outlets  260  as in the first embodiment. Alternatively however, the outlets  260  can be configured to provide different spray patterns, similar to the first embodiment. Another difference is that the slidable plate  272  of the valve body  270  has the same number of openings  274  as there are nozzle outlets  260 . The slidable plate  272  may be slidably mounted within the interior  258  of the rotatable spray arm  234  for movement between at least two positions, and both positions may result in the multiple openings  274  being fluidly coupled with the multiple outlets  260 . The valve body  270  may be formed such that the multiple openings  274  only partially close off a portion of the outlet  260  as the slidable plate  272  is moved between the first and second positions. In this manner, each paired outlet  260  and opening  274  may collectively form an effective opening or nozzle, and the slidable plate  272  may move to adjust the relative positions of the outlets  260  and opening  274  to alter the shape of the effective nozzle to control the shape of the spray and direction of liquid emitted from the outlet  260 . 
       FIG. 6A  illustrates a spray pattern that may be created when the slidable plate  272  is in the first position and  FIG. 6B  illustrates a spray pattern that may be created when the slidable plate  272  is in the second position. During operation, the lower rotatable spray arm  234 , valve body  270 , and actuator  280  operate much the same as in the first embodiment wherein as the lower rotatable spray arm  234  is rotated, the gears in the gear assembly  284  are driven and the slidable plate  272  is moved between the first and second positions. Alternatively, the rotatable spray arm  234  can be provided with a gear assembly similar to that of the second embodiment to achieve a higher gear reduction and longer dwell time. 
     As the slidable plate  272  is moved, the spray pattern from the outlets  260  is altered by the translation of the openings  274 , which acts to change the flow of liquid from the outlet  260  by both reducing the size and changing the shape of the effective nozzle formed by the outlet  260  and opening  274 . One result is that the direction of the liquid spraying from the outlets  260  is varied with the movement of the slidable plate  272 . When the plate  272  is in the first position as shown in  FIG. 6A , liquid may be sprayed out of the outlets  260  in a first direction generally toward one distal end of the spray arm  234  for a fixed number of revolutions. Likewise, when the plate  272  is in the second position as shown in  FIG. 6B , liquid may be sprayed out of the outlets  260  in a second direction, different than the first direction, generally toward the other distal end of the spray arm  234  for a fixed number of revolutions. Depending on the configuration of the outlets  260  and openings  274 , the first and second directions may be separated by an arc ranging between 45° and 120°. Furthermore, while not illustrated herein, as the plate  272  transitions between the first and second positions, liquid may be sprayed out of the outlets  260  in at least one, and possibly many, intermediate direction, generally upward from the spray arm  234  for a fixed number of revolutions. The actual time or amount of revolutions that the liquid is sprayed in each direction may be altered based on the design of the lower rotatable spray arm  234 , valve body  270 , spacing between the walls  295 ,  296 , pin location  292 , slot length  274 , and gear assembly  284 . 
     The force and shape of the pattern of the sprays emitted from the outlets  260  may also change with movement of the slidable plate  272 . As the openings  274  come into alignment with the outlets  260 , the effective nozzle becomes wider, and a more diffused, wide-angle spray pattern may be emitted from the effective nozzle that produces a shower spray of liquid from the spray arm  234 . Conversely, as the outlets  260  are overlapped with the solid plate portion of the slidable plate  272 , the effective nozzle becomes smaller, and a more discrete, focused, and concentrated the spray pattern may be emitted from the effective nozzle, which may provide a higher pressure spray from the spray arm  234 . The shower spray may be more suitable for distributing treating chemistry whereas the higher pressure spray may be more suitable for dislodging soils. The different spray patterns, including the differing directions of spray, created by the third embodiment may provide for different cleaning effects from the single spray arm  234 . Although the lower rotatable spray arm  234  has been described as being similar to the first embodiment it is contemplated that the profile and gear assembly  284  of the spray arm  234  may alternatively be formed like that disclosed with respect to the second embodiment. 
     It is also contemplated that the pressure of the spray may be changed by varying the number of nozzles open and/or varying the open area of the nozzles.  FIG. 7 . illustrates an exploded view of a fourth embodiment of an alternative lower rotatable spray arm  334  and a valve body  370  according to a fourth embodiment of the invention. The lower rotatable spray arm  334  and valve body  370  are similar to the lower rotatable spray arm  34  and valve body  70  previously described and therefore, like parts will be identified with like numerals increased by 300, with it being understood that the description of the like parts applies to the fourth embodiment, unless otherwise noted. 
     One difference between the lower rotatable spray arm  34  and the lower rotatable spray arm  334  is that the lower rotatable spray arm  334 , along with the valve body  370 , is capable of varying the pressure of liquid emanating from the outlets  360  by varying the number of outlets  360  open and/or varying the open area of the outlets  360 . In the first embodiment, if the same number of outlets remained open at each phase or the open area of the outlets did not change at each phase, then the nozzles were balanced and the pressure of liquid emanating from the nozzles did not change. The lower rotatable spray arm  334  is configured to vary the number of open nozzles and/or vary the cumulative open area of the nozzles during any one phase and as a result, the pressure from the nozzles may be varied throughout the cycle of operation. 
     In the illustrated example, the lower rotatable spray arm  334  includes a plurality of nozzles or outlets  360 , which have been denoted further with letters ranging from A-L and extend through the body  356  of the lower rotatable spray arm  334 . Each of the outlets  360  may be in fluid communication with a liquid passage (not shown) of the lower rotatable spray arm  334 . More specifically, the outlets  360  may be fluidly coupled with the liquid passage within the lower rotatable spray arm  334  through movement of the valve body  370  similar to the embodiments described above. Although not illustrated, each of the outlets  360  may have a corresponding nozzle provided on the body  356 . 
     It should be noted that the outlets  360  may be spaced in any variety of suitable manners along the lower rotatable spray arm  334  including that the outlets  360  may be offset from each other. In the illustrated example, a sealing ring  361  is included along an inner portion of the body  356  around each outlet  360 . Such a sealing ring  361  may allow an opening  374  in the valve body  370  to fluidly couple with the outlet  360  so long as the opening  374  is at least partially within the sealing ring  361 . The sealing ring may take any suitable form including that of an O-ring or other seal. The valve body  370  may be capable of sealing against the body  356  and the sealing rings  361  to better seal the outlets  360  against the unintended flow of liquid from the liquid passage. The outlets  360  have all been shown as being identical except that outlets E and H include a larger sealing ring  361  allowing outlets E and H to be coupled to the liquid passage for a longer time. Outlets E and H also include a slight larger outlet opening. However, it is contemplated that each of the outlets  360  may alternatively have an identical configuration. Further, the outlets  360  may be configured to provide for the same or different spray patterns as described in the above embodiments. 
     Another difference is that the slidable plate  372  of the valve body  370  has fewer openings, which are illustrated as eight openings. The slidable plate  372  may be slidably mounted within the interior of the rotatable spray arm  334  for movement between multiple positions. The outlets  360  of the rotatable spray arm  334  and the openings  374  of the valve body  370  may be spaced and located in any suitable manner to create any variety of sprays, patterns, and pressures of sprays as the valve body  370  moves through its various positions. 
     As an example,  FIG. 8 . illustrates which outlets  360  may be open to the interior of the exemplary rotatable spray arm  334  when the exemplary valve body  370  is in a first position,  FIG. 9 . illustrates which outlets  360  may be open to the interior of the rotatable spray arm  334  when the valve body  370  is in a second position, and  FIG. 10 . illustrates which outlets  360  may be open to the interior of the rotatable spray arm  334  when the valve body  370  is a third position. During operation, the lower rotatable spray arm  334 , valve body  370 , and actuator (not shown) operate much the same as in the first embodiment wherein as the lower rotatable spray arm  334  is rotated, gears in the gear assembly (not shown) are driven and the valve body  370  is moved between the first, second, and third positions. Alternatively, a gear assembly similar to that of the second embodiment may be used to achieve a higher gear reduction and longer dwell time. Further, still any suitable gear assembly or actuator may be used to move the valve body  370 . 
     Beginning with the valve body  370  in the first position, illustrated in  FIG. 8 , four of the eight openings  374  in the valve body  370  align with four of the nozzles in the lower rotatable spray arm  334 . Such outlets  360  have been denoted with the identifier “ON.” More specifically, the openings  374  align with the sealing rings  361  of outlets A, C, J, and L to allow liquid to spray out of the outlets  360 . As the valve body  370  is moved to the second position as illustrated in  FIG. 9 , the outlets A, C, J, and L are no longer fluidly coupled to the interior of the lower rotatable spray arm  334 . Instead four of the eight openings  374  in the valve body  370  align with four other of the outlets  360  in the lower rotatable spray arm  334 . More specifically, the openings  374  align with the outlets E, F, G, and H. As illustrated, the outlets A, C, J, and L spans a different amount of the lower rotatable spray arm  334  than the outlets E, F, G, and H. 
     When the valve body  370  moves to the third position, illustrated in  FIG. 10 , only two of the eight openings  374  in the valve body  370  align with two of the outlets  360  in the lower rotatable spray arm  334 . More specifically, two of the openings  374  align with the outlets E and H. Outlets E and H are a subset of the outlets E, F, G, and H. Clearly the subset including outlets E and H have fewer outlets  350  then the subset of outlets E, F, G, and H. Outlets E, F, G, and H spans a greater radial distance along the lower rotatable spray arm  334  than the outlets E and H. As the sealing rings  361  of the outlets E and H are larger those outlets  360  are fluidly coupled with the interior of the lower rotatable spray arm  334  for a longer period of time, and thus to spray liquid for a longer period of time. Because only two outlets  360  are open the interior of the lower rotatable spray arm this position creates a higher pressure spray than the other illustrated positions. The actual time or amount of revolutions that the liquid is sprayed from each of the outlets  360  may be altered based on the design of the lower rotatable spray arm  334 , valve body  370 , etc. 
     In this manner, it is contemplated that through various movement of the valve body  370  that a variety of subsets of the outlets  360  may be fluidly coupled to the liquid passage and that this may cause a pressure of liquid emanating from the outlets  360  to vary. In the illustrated example of  FIG. 10  both the number of outlets  360  and the open area or cumulative cross-sectional area of the outlets  360  was changed. The first subset of the plurality of outlets  360 , outlets E and H, have less cumulative cross-sectional area than a second subset of the plurality of outlets  360 , formed by outlets E, F, G, and H. In this manner, the liquid emitted from the first subset of the plurality of outlets may be at a cumulative speed or cumulative pressure greater than the second subset. Because the same number and cross-sectional area of outlets are not always spraying liquid an unbalanced configuration may be formed resulting in the pressure of the liquid emanated from the outlets  360  to be varied. In the illustrated example, all of the outlets of outlets  360  have the same cross-sectional area; however, it will be understood that instead of varying the number of outlets  360  open at any one time, the cumulative cross-sectional area of the outlets  360  fluidly coupled with the interior of the lower rotatable spray arm  334  may be changed but the number of outlets  360  fluidly coupled with the interior of the lower rotatable spray arm  334  may remain the same. This will also have the effect of liquid being emitted from at least one of the outlets of the first subset, having less cumulative cross-sectional area, at a greater pressure or speed than from at least one of the outlets of the second subset, having a greater cumulative cross-sectional area. Further, both the number of outlets and the cumulative cross-sectional area may be changed. 
     It will be understood that the outlets  360  and the openings  374  in the valve body  370  may be arranged in a variety of ways to create a multitude of different phases and spray pressures. Further, the subsets of nozzles open during any position of the valve body may be sequentially adjacent each other or may be spaced from each other depending upon the arrangement of outlets  360  and openings  374 . Further, the force and shape of the pattern of the sprays emitted from the outlets  360  may also change with movement of the valve body  370 . 
     There are several advantages of the present disclosure arising from the various features of the apparatuses described herein. For example, the embodiments described above allow for additional coverage of the treating chamber  20  with multiple spray patterns. The first and second embodiments allow for multiple types of spray nozzles having multiple spray patterns, which may be used during a cycle of operation, which in turn may result in better cleaning of utensils within the treating chamber  20  with no additional liquid consumption. Further, because the lower rotatable sprayers have multiple subsets of outlets and each multiple subset has a smaller total nozzle area than current spray arm designs, lower flow rates may be used and this may result in less liquid or water being required. This may increase the velocity of the spray emitted from each of the first and second subsets of nozzles while not sacrificing coverage or individual nozzle size. Further, with less liquid flow needed, a smaller recirculation pump having a smaller motor may also be used which may result in a cost and energy savings. The third embodiment described above allows for a single type of nozzle which emits varying spray patterns, including sprays in different directions and having different intensities, which may result in additional coverage of the treating chamber  20  and better cleaning of utensils within the treating chamber  20  with no additional liquid consumption. Further, the fourth embodiment described above allows for a wash zone having a higher pressure for tougher soil to be created. 
     While the invention has been specifically described in connection with certain specific embodiments thereof, it is to be understood that this is by way of illustration and not of limitation. For example, it has been contemplated that the valve body and actuator may be located in other rotatable spray arms such as a mid-level rotatable spray arm. Further, other actuators may be used to control the movement of the valve body based on the rotation of the lower rotatable spray arm and the illustrated actuators including gear assemblies are merely exemplary. Further, although both gear assemblies illustrated include the same number of gears, it has been contemplated that the gear assembly may include any number of gears. Further, even though the gear assemblies are shown in a stacked configuration they could organized in a more horizontal layout. 
     Further, while the valve body has been illustrated and described as moving in a linear motion it is contemplated that the valve body may alternatively be moved in an orbital motion. Such a motion could be created in a variety of ways including, by way of non-limiting example, replacing the pin described above with a pivot pin, which is mounted to the valve body slightly off center of the final gear, which would allow the plate to orbit. Alternatively, one end of the valve body may have a pin in a short longitudinal slot defining one end, while the other end orbits. As yet another non-limiting alternative, an additional gear may be added in the same plane as the fourth gear and may be of the same size and thus rotate at a synchronized speed with the fourth gear. A pin may be included on this additional gear and may orbit in unison with and retain a constant distance from the other pin. Since the valve plate is engaged to both pins the entire plate would be caused to orbit. With the valve body, or a portion of the valve body, capable of orbital motion the multiple openings may be dispersed in a two-dimension plane in a wider variety of ways such that the outlets could be changed when the valve body orbits. Further, the valve body could be made to orbit around the multiple openings to allow for sprays in all directions. 
     Further still, while the sprayer has been illustrated and described as a rotatable spray arm it will be understood that any suitable sprayer may be used. For example, a non-rotatable spray arm may be used and the actuator may move the valve body within the spray arm. Further, a sprayer having a different shape may be used and may be either rotatable or non-rotatable. Similarly, while the valve body has been described and illustrated as a slidable plate it is contemplated that the valve body may take any suitable form and that the slidable plate may take any suitable form. For example, the slidable plate may include a rigid plate, a flexible plate, or a thin film plate, which may be either flexible or rigid. Further, it will be understood that any features of the above described embodiments may be combined in any manner. 
     The patentable scope of the invention is defined by the claims, and may include other examples that occur to those skilled in the art. Reasonable variation and modification are possible within the scope of the forgoing disclosure and drawings without departing from the spirit of the invention which is defined in the appended claims.