Abstract:
A passive diverter is provided that does not require a dedicated motor to switch between multiple outlet ports. The diverter uses a flow of fluid provided by a pump to switch between different outlet ports. In a dishwashing appliance, fluid from the pump that supplies one or more spray assemblies can be used to cause the diverter to switch between different fluid outlets and e.g., different spray assemblies. A separate motor to power the diverter is not required, which allows a savings in costs and space.

Description:
FIELD OF THE INVENTION 
     The subject matter of the present disclosure relates generally to a diverter for an appliance. 
     BACKGROUND OF THE INVENTION 
     Dishwasher appliances generally include a tub that defines a wash compartment. Rack assemblies can be mounted within the wash compartment of the tub for receipt of articles for washing. Spray assemblies within the wash compartment can apply or direct wash fluid towards articles disposed within the rack assemblies in order to clean such articles. Multiple spray assemblies can be provided including e.g., a lower spray arm assembly mounted to the tub at a bottom of the wash compartment, 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 compartment. Other configurations may be used as well. 
     A dishwashing appliance is typically equipped with at least one pump for circulating fluid through the spray assemblies. However, due to e.g., government regulations related to energy and/or water usage, the pump may not be able to supply fluid to all spray assemblies at the same time. Accordingly, a dishwashing appliance that can be configured to selectively control the flow through different spray assemblies or other fluid elements would be useful. 
     Certain conventional dishwashing appliances use a device, referred to as a diverter, to control the flow of fluid in the dishwashing appliance. For example, the diverter can be used to selectively control which flow assemblies receive a flow of fluid. In one construction, the diverter uses an electrically powered motor to rotate an element between different ports for fluid control. The motor adds a significant expense to the overall manufacturing cost of the dishwashing appliance and must be separately controlled during cleaning operations so that the proper flow is occurring. 
     Additionally, the motor is typically positioned below the diverter, which is positioned below the sump portion of the appliance. As such, significant space is consumed which can reduce the space available in the dishwashing compartment for placement of dishes, glasses, silverware, and other items for cleaning. Thus, a diverter that does not require an electrically powered motor to operate would be beneficial, resulting in a savings in both costs and space. 
     BRIEF DESCRIPTION OF THE INVENTION 
     The present invention provides a passive diverter, i.e.—a diverter that does not require a dedicated motor to switch between multiple outlet ports. The diverter uses the forces provided by a flow of fluid from a pump to switch between different outlet ports. In a dishwashing appliance, fluid from the pump that e.g., supplies one or more spray assemblies can be used to cause the diverter to switch between different fluid outlets and the different spray assemblies or other fluid-using elements. A separate motor to power the diverter is not required, which allows a savings in costs and space. Additional 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 one exemplary embodiment, the present invention provides a dishwasher appliance. The dishwasher appliance includes a tub that defines a wash chamber for receipt of articles for washing and a pump for providing fluid flow for cleaning the articles. A diverter receives fluid flow from the pump. The diverter defines an axial direction and has a plurality of outlet ports for providing fluid to the wash chamber. The diverter includes a housing defining a chamber. The chamber has a fluid inlet and a fluid outlet to supply fluid to the outlet ports. A disk is positioned within the fluid outlet and rotatable about an axis. The disk defines an aperture for selectively controlling fluid flow from the chamber through one of the outlet ports. The disk is movable along the axial direction between a first position and a second position. The disk defines a channel and a plurality of cams projecting into the channel. A biasing element is configured to urge the rotatable disk into the first position. A boss extends from the housing into the channel of the disk. The boss defines a plurality of guide elements. The guide elements and cams are configured to interact so that movement of the disk along the axial direction between the first position and the second position causes the disk to rotate about the axis. 
     In another exemplary embodiment, the present invention provides a passive diverter for selectively controlling fluid flow in an appliance. The passive diverter defines an axial direction and includes a housing having a chamber and a plurality of fluid outlet ports for providing selective control of fluid flow for the appliance. The chamber has a fluid inlet and a fluid outlet to supply fluid to the outlet ports. A disk is positioned within the fluid outlet and is rotatable about an axis. The disk defines an aperture for selectively controlling fluid flow from the chamber through one of the outlet ports. The disk is movable along the axial direction between a first position and a second position. The disk defines a channel and a plurality of cams projecting into the channel. A biasing element is configured to urge the rotatable disk into the first position. A boss extends from the housing into the channel of the disk. The boss defines a plurality of guide elements, wherein the guide elements and cams are configured to interact so that movement of the disk along the axial direction between the first position and the second position causes the disk to rotate about the axis. 
     These and other features, aspects, and advantages of the present invention 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 of the present invention 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 front view of an exemplary embodiment of a dishwashing appliance of the present invention. 
         FIG. 2  provides a side, cross-sectional view of the exemplary dishwashing appliance of  FIG. 1 . 
         FIG. 3  is a perspective view of an exemplary embodiment of a passive diverter of the present invention. 
         FIG. 4  is a cross-sectional view of the exemplary passive diverter of  FIG. 3  with an internal disk shown in a first position. 
         FIG. 5  is also a cross-sectional view of the exemplary passive diverter of  FIG. 3  with an internal disk shown in a second position. 
         FIG. 6  is a bottom view of a top portion of a housing forming the exemplary passive diverter of  FIG. 3 . 
         FIG. 7  is a bottom, perspective view of the top portion of the housing forming the exemplary passive diverter of  FIG. 3 . 
         FIG. 8  is a cross-sectional, side view of the top portion of the housing forming the exemplary passive diverter of  FIG. 3 . 
         FIG. 9  is a perspective view of an exemplary embodiment of a rotating disk of the present invention. 
         FIG. 10  is a cross-sectional, side view of the exemplary disk of  FIG. 9 . 
         FIG. 11  is a side view of a feature (e.g., boss) that extends from the exemplary disk of  FIGS. 9 and 10 . 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     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. 
     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 the cleaning process where a dishwashing appliance operates while containing 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 the cleaning process in 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 “drying cycle” is intended to refer to one or more periods of time in which the dishwashing appliance is operated to dry the articles by removing fluids from the wash chamber. The term “fluid” refers to a liquid used for washing and/or rinsing the articles and is typically made up of water that may include additives such as e.g., detergent or other treatments. 
       FIGS. 1 and 2  depict an exemplary domestic dishwasher  100  that may be configured in accordance with aspects of the present disclosure. For the particular embodiment of  FIGS. 1 and 2 , the dishwasher  100  includes a cabinet  102  having a tub  104  therein that defines a wash chamber  106 . The tub  104  includes a front opening (not shown) and a door  120  hinged at its bottom  122  for movement between a normally closed vertical position (shown in  FIGS. 1 and 2 ), wherein the wash chamber  106  is sealed shut for washing operation, and a horizontal open position for loading and unloading of articles from the dishwasher. Latch  156  is used to lock and unlock door  120  for access to chamber  106 . 
     Upper and lower guide rails  124 ,  126  are mounted on tub side walls  128  and accommodate roller-equipped rack assemblies  130  and  132 . Each of the rack assemblies  130 ,  132  is fabricated into lattice structures including a plurality of elongated members  134  (for clarity of illustration, not all elongated members making up assemblies  130  and  132  are shown in  FIG. 2 ). Each rack  130 ,  132  is adapted for movement between an extended loading position (not shown) in which the rack is substantially positioned outside the wash chamber  106 , and a retracted position (shown in  FIGS. 1 and 2 ) in which the rack is located inside the wash chamber  106 . This is facilitated by rollers  135  and  139 , for example, mounted onto racks  130  and  132 , respectively. A silverware basket (not shown) may be removably attached to rack assembly  132  for placement of silverware, utensils, and the like, that are otherwise too small to be accommodated by the racks  130 ,  132 . 
     The dishwasher  100  further includes a lower spray-arm assembly  144  that is rotatably mounted within a lower region  146  of the wash chamber  106  and above a tub sump portion  142  so as to rotate in relatively close proximity to rack assembly  132 . A mid-level spray-arm assembly  148  is located in an upper region of the wash chamber  106  and may be located in close proximity to upper rack  130 . Additionally, an upper spray assembly  150  may be located above the upper rack  130 . 
     The lower and mid-level spray-arm assemblies  144 ,  148  and the upper spray assembly  150  are part of a fluid circulation assembly  152  for circulating water and dishwasher fluid in the tub  104 . The fluid circulation assembly  152  also includes a pump  154  positioned in a machinery compartment  140  located below the tub sump portion  142  (i.e., bottom wall) of the tub  104 , as generally recognized in the art. Pump  154  receives fluid from sump  142  and provides a flow to the inlet  210  of a passive diverter  200  as more fully described below. 
     Each spray-arm assembly  144 ,  148  includes an arrangement of discharge ports or orifices for directing washing liquid received from diverter  200  onto dishes or other articles located in rack assemblies  130  and  132 . The arrangement of the discharge ports in spray-arm assemblies  144 ,  148  provides a rotational force by virtue of washing fluid flowing through the discharge ports. The resultant rotation of the spray-arm assemblies  144 ,  148  and the operation of spray assembly  150  using fluid from diverter  200  provides coverage of dishes and other dishwasher contents with a washing spray. Other configurations of spray assemblies may be used as well. 
     The dishwasher  100  is further equipped with a controller  137  to regulate operation of the dishwasher  100 . The controller may 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. 
     The controller  137  may be positioned in a variety of locations throughout dishwasher  100 . In the illustrated embodiment, the controller  137  may be located within a control panel area  121  of door  120  as shown in  FIGS. 1 and 2 . In such an embodiment, input/output (“I/O”) signals may be routed between the control system and various operational components of dishwasher  100  along wiring harnesses that may be routed through the bottom  122  of door  120 . Typically, the controller  137  includes a user interface panel/controls  136  through which a user may select various operational features and modes and monitor progress of the dishwasher  100 . In one embodiment, the user interface  136  may represent a general purpose I/O (“GPIO”) device or functional block. In one embodiment, the user interface  136  may 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 interface  136  may include a display component, such as a digital or analog display device designed to provide operational feedback to a user. The user interface  136  may be in communication with the controller  137  via 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 dishwasher. The exemplary embodiment depicted in  FIGS. 1 and 2  is for illustrative purposes only. For example, different locations may be provided for user interface  136 , different configurations may be provided for racks  130 ,  132 , and other differences may be applied as well. 
       FIG. 3  provides a top, perspective view of an exemplary embodiment of a passive diverter  200  of the present invention. Passive diverter  200  has a diverter inlet  210  for receiving a flow of fluid from pump  154  that is to be supplied to spray assemblies  144 ,  148 , and/or  150  as well as other fluid-using components during cleaning operations. As stated, pump  154  receives fluid from e.g., sump  142  and provides a fluid flow to diverter  200 . 
     For this exemplary embodiment, diverter  200  includes a first outlet port  202 , a second outlet port  204 , a third outlet port  206 , and a fourth outlet port  208 . However, in other embodiments of the invention, two, three, or more than four outlet ports may be used with diverter  200  depending upon e.g., the number of switchable ports desired for selectively placing pump  154  in fluid communication with different fluid-using elements of appliance  100 . Diverter  200  includes a rotatable disk  222  ( FIG. 9 ), more fully described below, that can be selectively switched between ports  202 ,  204 ,  206 , and  208  without using a separate motor for such purpose. More particularly, disk  222  can be rotated so as to place its aperture  230  in fluid communication with any one of ports  202 ,  204 ,  206 , and  208 . As such, passive diverter  200  can be used to selectively provide fluid flow from pump  154  through any one of the outlet ports  202 ,  204 ,  206 , and  208  desired. 
     By way of example, first outlet port  202  can be fluidly connected with upper spray assembly  150 , second outlet port can be fluidly connected with mid-level spray arm assembly  148 , and third and fourth outlet ports  206  and  208  might be fluidly connected with lower spray arm assembly  144 . Other connection configurations may be used as well. As such, the rotation of disk  222  in passive diverter  200  can be used to selectively place pump  154  in fluid communication with any one of the spray assemblies  144 ,  148 , or  150  by way of outlet ports  202 ,  204 ,  206 , and  208 . Diverter  200  includes multiple apertures  212  that allow for fastening diverter  200  to the sump  142  of wash tub  104  ( FIG. 2 ). 
     Referring now to  FIGS. 3, 4, and 5 , diverter  200  is constructed from a housing  214  that includes a top portion  224  and a bottom portion  226 . An O-ring  254  provides a seal therebetween. Housing  214  defines a chamber  216  into which fluid flows through its fluid inlet  218 . Chamber  216  also defines a fluid outlet  220 , which is formed by the circular edge  244  at the top of bottom portion  226  ( FIGS. 4 and 5 ). 
     Disk  222  is positioned within fluid outlet  220  of chamber  216 . More particularly, disk  222  includes a cylindrically-shaped shaft  278  received into a cylindrically-shaped socket  280  formed by bottom portion  226  of housing  214 . Disk  222  is rotatable about axis A-A relative to housing  214 . 
     As can be seen by comparing  FIGS. 4 and 5 , disk  222  is movable along the axial direction A (or along axis A-A, which is parallel to the axial direction A) between a first position shown in  FIG. 4  and a second position shown in  FIG. 5 . In the first position shown in  FIG. 4 , disk  222  rests on housing  214 . More particularly, referring to  FIGS. 4 and 10 , disk  222  includes a frustoconical surface  246  positioned on the distal end of a flange  234 . In turn, flange  234  projects along axial direction A from circular main body  248  of disk  222  towards fluid outlet  220  formed by bottom portion  226  of housing  214 . In the first position, frustoconical surface  246  rests in a complementary manner on an interior surface  236  of bottom portion  226  that is also frustoconical in shape. In the second position shown in  FIG. 5 , disk  222  is pressed against diverter top  224 . For this exemplary embodiment, a top surface  250  ( FIGS. 9 and 10 ) of disk  222  contacts an interior surface  252  of top portion  224 . 
     Movement of disk  222  back and forth between the first position shown in  FIG. 4  and the second position shown in  FIG. 5  is provided by two opposing forces: i) a flow of water passing through diverter  200  that is counteracted by ii) a biasing element  228 . More particularly, when pump  154  is off, biasing element  228  pushes along axial direction A against disk  222  and forces it downward along axis A-A (arrows D) to the position shown in  FIG. 4 . Conversely, when there is a sufficient flow of fluid F through diverter housing  200 , the momentum of fluid exiting chamber  216  through the fluid outlet  220  of housing  214  will impact disk  222 . As the fluid passes through aperture  230  to exit diverter  200  through one of the outlet ports, this momentum overcomes the force provided by biasing element  228  so as to shift disk  222  along axial direction A (arrows U) away from diverter bottom  226  towards diverter top  224  to a second position shown in  FIG. 5 . Flange  234  assists in capturing the momentum provided by fluid flow through fluid outlet  220 . Disk  222  will remain in the second position until the fluid flow ends or drops below a certain level. Then, biasing element  228  (shown in this exemplary embodiment as a compression spring  228 ) urges disk  222  along axial direction A away from diverter top  224  towards diverter bottom  226  and back into the first position shown in  FIG. 4 . The use of the terms “top” and “bottom,” or “upper” and “lower” herein are used for reference only as diverter  200  is not limited to the vertical orientation shown nor to a two piece assembly for housing  214 ; other constructions and orientations may also be used. 
     The movement of disk  222  back and forth along axis A-A between the first and second positions shown in  FIGS. 4 and 5  also causes disk  222  to rotate about axis A-A so that aperture  230  is switched between the various outlet ports  202 ,  204 ,  206 , and  208 . For this exemplary embodiment, a single movement in either direction (arrow U or arrow D) causes disk  222  to rotate 45 degrees. Accordingly, disk  222  rotates about axis A-A a full 90 degrees each time it is moved out of, and then returned to, either the first position ( FIG. 4 ) or the second position ( FIG. 5 ). 
     As shown in  FIG. 6 , for this exemplary embodiment, outlet ports  202 ,  204 ,  206 , and  208  are spaced apart along the circumferential direction C at angles of 90 degrees. Thus, the rotation of disk  222  by 90 degrees necessarily rotates aperture  230  so as to selectively provide fluid flow from one outlet port to the next outlet port along the direction of rotation. For example, in  FIG. 5 , aperture  230  places pump  154  in fluid communication with port  202  so that fluid flows out of port  202 . As aperture  230  is rotated 90 degrees clockwise (as viewed looking down on top  224  of passive diverter  200 ), it places pump  154  in fluid communication with port  208  so that fluids flow out of port  208 . Continued rotation of disk  222  can provide flow through port  206 , then port  204 , and then back to port  202 . 
     Referring now to  FIGS. 6, 7, and 8 , a cylindrically-shaped boss  240  extends along axis A-A from top portion  224  of housing  214  into a channel  232  ( FIG. 10 ) defined by disk  222 . Boss  240  defines recess  238  into which a first end of biasing element  228  is received. Boss  240  also includes a plurality of guide elements  256  and  258  that are spaced apart from each other along circumferential direction C. A first plurality of guide elements  256  are located near a distal end  260  of boss  240  while a second plurality of guide elements  258  are located near diverter top  224 . Guide elements  256  and  258  are spaced apart along axial direction A and are also offset from each other along circumferential direction C. More particularly, as best seen in  FIGS. 6 and 7 , along axial direction A, each of the second plurality of guide elements  258  is aligned with a gap  264  positioned between a respective pair of the first plurality of guide elements  256 . Conversely, each of the first plurality of guide elements  256  is aligned with a gap  262  between a respective pair of the second plurality of guide elements  258 . 
     Referring now to  FIG. 11 , each of the guide elements  256  and  258  includes a contact face  266  and  268 , respectively. Each face  266  and  268  is at a non-zero angle between zero and 90 degrees from the axial direction A. For the exemplary embodiment shown, this angle is about 45 degrees. In another embodiment, this angle is about 42 degrees. In still another embodiment, this angle is about 40 degrees to about 50 degrees from the axial direction. However, other angles may be used as well. 
     As stated and shown, boss  240  is received into a channel  232  formed by disk  222 . Referring to  FIGS. 9 and 10 , a plurality of cams  242  project along radial direction R into channel  232 . Each cam  242  includes an upper contact face  270  and a lower contact face  272 . A pin  274  forms a second recess or annulus  276  into which a second end of biasing element  228  is received. 
     Referring now to  FIGS. 10 and 11 , as a flow of fluid overcomes biasing element  228  and disk  222  moves from the first position ( FIG. 4 ) towards the second position ( FIG. 5 ), upper contact face  270  of each cam  242  contacts a guide element  258 . Disk  222  is caused to rotate 45 degrees so that each cam  242  moves into a gap  262  between a pair of the second plurality of guide elements  258 . This movement is guided by contact face  268 . In this second position ( FIG. 5 ), opening  230  is aligned with one of the outlet ports  202 ,  204 ,  206 , or  208 . As the flow of fluid is turned off, biasing element  228  causes disk  222  to move towards the first position ( FIG. 4 ). During this movement, lower contact face  272  of each cam  242  contacts a guide element  256  and causes disk  222  to rotate another 45 degrees so that each cam  242  moves into a gap  264  between a pair of the first plurality of guide elements  256 . This movement is guided by contact face  266 . Upon returning to the second position, disk  222  is again caused to rotate by 45 degrees as previously described so that aperture  230  is now switched to the next outlet port. The process can be repeated to switch to still another outlet port. 
     Accordingly, during operation of appliance  100 , controller  137  can be programmed to operate pump  154  and control the position of disk  222 . For example, knowing the last outlet port through which fluid flow occurred, controller  137  can activate pump  154  to rotate disk  222  to the next outlet port in the direction of rotation of disk  222  so as to control the flow of fluid. Each time pump  154  is cycled off and back on to provide a flow of fluid through passive diverter  200  (e.g., during or between wash and rinse cycles), the controller  137  will “know” that disk  222  has been rotated to the next outlet port. 
     As stated, the passive diverter of the present invention may be used with more or less than four outlet ports. In such case, as will be understood by one of skill in the art using the teachings disclosed herein, the configuration of cams and guide elements described above can be modified to provide the desired amount of rotation between the selected number of outlet ports. Four cams along with four upper and four lower guide elements are used to provide 90 degrees of rotation between four outlet ports in the exemplary embodiment above described. By way of example, three cams along with three upper and three lower guide elements could be used to provide 120 degrees of rotation between three outlet ports and so forth. 
     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 language of the claims.