Patent Publication Number: US-10765293-B2

Title: Dishwasher with vertically adjustable dish rack

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is a divisional of U.S. application Ser. No. 15/797,647, filed Oct. 30, 2017, now issued as U.S. Pat. No. 10,582,829 and entitled Dishwasher with Vertically Adjustable Dish Rack, which is incorporated by reference herein in its entirety. 
    
    
     BACKGROUND 
     Contemporary automatic dishwashers for use in a typical household include a tub that can have an open front and at least partially defines a treating chamber into which items, such as kitchenware, glassware, and the like, can be placed to undergo a washing operation. At least one rack or basket for supporting soiled dishes can be provided within the tub. A spraying system with multiple sprayers can be provided for recirculating liquid throughout the tub to remove soils from the dishes. The dishwasher can be provided with a door, which can be pivotally mounted to the tub, that closes the open front. The at least one rack or basket can be provided in the form of upper and lower dish racks. The upper and lower dish racks can be separated by a defined vertical spacing that limits the overall size of items that can be placed in the dishwasher. 
     In order to provide more flexibility to users, adjustment assemblies can be provided that enable at least one dish rack to be vertically adjustable. Most commonly, the upper dish rack can be vertically shifted to increase or decrease the defined vertical spacing between the upper and lower dish racks. Typically, the adjustment assemblies are mounted on opposing sides of the dish rack and connect to support rails that permit the dish rack to move in and out of the treating chamber. Such adjustment assemblies can have complicated structure, can be difficult to operate in transitioning from one height position to another, are unstable and/or are simply not reliable. 
     BRIEF SUMMARY 
     In an aspect, the present disclosure relates to a method of adjusting a dish rack supported for selective movement between lowered and raised positions within a dishwasher tub, the method including moving an actuator from an undepressed position to a depressed position wherein a locking lever pivots from an engaging position where the dish rack is held in place to a release position where the dish rack is vertically movable between lowered and raised positions, and biasing the actuator by a biasing element to an undepressed position when the actuator is not depressed. 
     In another aspect, the description relates to a method of adjusting a dish rack supported for selective movement between lowered and raised positions within a dishwasher tub comprising: moving an actuator from an undepressed position to a depressed position wherein a locking lever pivots from an engaging position where the dish rack is held in place to a release position where the dish rack is vertically movable between lowered and raised positions; and biasing the actuator by a biasing element to the undepressed position when the actuator is not depressed. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       In the drawings: 
         FIG. 1  illustrates a schematic, side view of a dishwasher according to an embodiment of the present disclosure. 
         FIG. 2  illustrates a schematic view of a controller for use with the dishwasher of  FIG. 1 . 
         FIG. 3  illustrates a perspective view of the dishwasher of  FIG. 1  including a dish rack having a rack height adjustment assembly in accordance with an embodiment of the present disclosure. 
         FIG. 4  illustrates a perspective view of the rack height adjustment assembly of  FIG. 3  according to an embodiment of the present disclosure. 
         FIG. 5  illustrates a cross-sectional side view of the rack height adjustment assembly of  FIG. 4  in a raised position and with a locking lever in an engaging position according to a first embodiment of the present disclosure. 
         FIG. 6  illustrates the rack height adjustment assembly of  FIG. 5  in the raised position with the locking lever in a release position. 
         FIG. 7  illustrates the rack height adjustment assembly of  FIG. 5  in a lowered position and with the locking lever in the release position. 
         FIG. 8  illustrates the rack height adjustment assembly of  FIG. 5  in the lowered position and with the locking lever in the engaging position. 
         FIG. 9  illustrates a cross-sectional side view of the rack height adjustment assembly of  FIG. 4  in the raised position and with the locking lever in the engaging position according to another embodiment of the present disclosure. 
         FIG. 10  illustrates the rack height adjustment assembly of  FIG. 9  in the raised position and with the locking lever in the release position. 
     
    
    
     DETAILED DESCRIPTION OF EMBODIMENTS OF THE INVENTION 
       FIG. 1  is a schematic, side view of a dishwasher  10  for treating dishes according to an automatic cycle of operation, according to an embodiment of the present disclosure. In  FIG. 1 , the dishwasher  10  includes a chassis  12  defining an interior. Depending on whether the dishwasher  10  is a stand-alone or built-in dishwasher, the chassis  12  can be a 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 can also be implemented in other types of dishwashing units, such as in-sink dishwashers, multi-tub dishwashers, or drawer-type dishwashers. 
     A controller  14  can be located within the chassis  12  and can 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  can be provided on the dishwasher  10  and coupled with the controller  14 . The user interface  16  can be provided on the chassis  12  or on the outer panel of the door  22  and can include operational controls such as dials, lights, switches, and displays enabling a user to input commands, such as a cycle of operation, to the controller  14  and receive information about the selected cycle of operation. 
     A tub  18  is located within the interior of and mounted to the chassis  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 , can be hingedly or pivotally mounted to the chassis  12  and can selectively move between an opened position, wherein the user can 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 . 
     Dish holders in the form of upper and lower racks  24 ,  26  are located within the treating chamber  20  and receive dishes 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 “dish(es)” 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, silverware, and other utensils. While not shown, additional dish holders, such as a silverware basket on the interior of the door  22  or a third level rack above the upper rack  24  can also be provided. 
     A spraying system  28  can 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 sprayer  34 , and a spray manifold  36 . The upper sprayer  30  can 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 sprayer  32  and lower sprayer  34  are located beneath upper rack  24  and lower rack  26 , respectively, and are illustrated as rotating spray arms. The mid-level sprayer  32  can provide a liquid spray upwardly through the bottom of the upper rack  24 . The lower sprayer  34  can provide a liquid spray upwardly through the bottom of the lower rack  26 . The mid-level sprayer  32  can 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  can be fixedly mounted to the tub  18  adjacent to the lower rack  26  and can provide a liquid spray laterally through a side of the lower rack  26 . The spray manifold  36  is not limited to this position; rather, the spray manifold  36  can be located in any suitable part of the treating chamber  20 . While not illustrated herein, the spray manifold  36  can include multiple spray nozzles having apertures configured to spray wash liquid towards the lower rack  26 . The spray nozzles can 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. Instead of or in addition to the spray manifold  36  provided on the rear wall, nozzles can be provided on the right and left side walls of the tub  18 . 
     A liquid recirculation system can be provided for recirculating liquid from the treating chamber  20  to the spraying system  28 . The recirculation system can include a sump  38  and a pump assembly  40 . The sump  38  collects the liquid sprayed in the treating chamber  20  and can be formed by a sloped or recess portion of a bottom wall  42  of the tub  18 . The pump assembly  40  can include both a drain pump  44  and a recirculation pump  46 . 
     The liquid recirculation system can also be fluidly coupled with a water supply line  47  for receiving fresh water from a water supply source, such as a household water supply, as well as a water supply circuit. The water supply circuit comprises a household inlet fitting  60 , which is carried by the chassis  12 , a conduit  62  that fluidly couples the inlet fitting  60  to the tub  18 , and an actuatable valve  80 . The actuatable valve  80  selectively controls the flow of liquid through the conduit  62 , allowing the flow of liquid from the conduit  62  into the tub  18  when the actuatable valve  80  is in an opened position, and preventing the flow of liquid from the conduit  62  into the tub  18  when the actuatable valve  80  is in a closed position. 
     The drain pump  44  can 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  can draw liquid from the sump  38  and pump the liquid through the spray system  28  to supply liquid into the treating chamber  20  through a supply tube  50  to one or more of the sprayers  30 ,  32 ,  34 ,  36 . In this manner, liquid can circulate from the sump  38  through the liquid recirculation system to the spray system  28  and back to the sump  38  to define a liquid recirculation circuit or flow path. 
     While the pump assembly  40  is illustrated as having separate drain and recirculation pumps  44 ,  46  in an alternative embodiment, the pump assembly  40  can 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. 
     A heating system having a heater  52  can be located within or near the sump  38  for heating liquid contained in the sump  38 . The heater  52  can also heat air contained in the treating chamber  20 . Alternatively, a separate heating element (not shown) can be provided for heating the air circulated through the treating chamber  20 . A filtering system (not shown) can be fluidly coupled with the recirculation flow path for filtering the recirculated liquid. 
     A user-accessible dispensing system can be provided for storing and dispensing one or more treating chemistries to the treating chamber  20 . As shown herein, the user-accessible dispensing system can include a dispenser  54  mounted on an inside surface of the door  22  such that the dispenser  54  is disposed in the treating chamber  20  when the door  22  is in the closed position. The dispenser  54  is configured to dispense treating chemistry to the dishes within the treating chamber  20 . The dispenser  54  can have one or more compartments  56  closed by a door  58  on the inner surface of the door  22 . The dispenser  54  can be a single use dispenser which holds a single dose of treating chemistry, a bulk dispenser which holds a bulk supply of treating chemistry and which is adapted to dispense a dose of treating chemistry from the bulk supply during a cycle of operation, or a combination of both a single use and bulk dispenser. 
     The dispenser  54  can further be configured to hold multiple different treating chemistries. For example, the dispenser  54  can have multiple compartments defining different chambers in which treating chemistries can be held. While shown as being disposed on the door  22 , other locations of the dispenser  54  are possible. However, the dispenser  54  is positioned to be accessed by the user for refilling of the dispenser  54 , whether it is necessary to refill the dispenser  54  before each cycle (i.e. for a single user dispenser) or only periodically (i.e. for a bulk dispenser). 
       FIG. 2  is a schematic view of the controller  14  of the dishwasher  10  of  FIG. 1 . As illustrated schematically in  FIG. 2 , the controller  14  can be coupled with the heater  52  for heating the wash liquid during a cycle of operation, the drain pump  44  for draining liquid from the treating chamber  20 , the recirculation pump  46  for recirculating the wash liquid during the cycle of operation, the user-accessible dispenser  54  for selectively dispensing treating chemistry to the treating chamber  20 , and the actuatable valve  80  to selectively control the flow of liquid through the conduit  62  into the tub  18 . 
     The controller  14  can be provided with a memory  64  and a central processing unit (CPU)  66 . The memory  64  can be used for storing control software that can be executed by the CPU  66  in completing a cycle of operation using the dishwasher  10  and any additional software. For example, the memory  64  can store one or more pre-programmed cycles of operation that can be selected by a user and completed by the dishwasher  10 . A cycle of operation for the dishwasher  10  can include one or more of the following steps: a wash step, a rinse step, and a drying step. The wash step can further include a pre-wash step and a main wash step. The rinse step can also include multiple steps such as one or more additional rinsing steps performed in addition to a first rinsing. The amounts of water and/or rinse aid used during each of the multiple rinse steps can be varied. The drying step can have a non-heated drying step (so called “air only”), a heated drying step or a combination thereof. These multiple steps can also be performed by the dishwasher  10  in any desired combination. 
     The controller  14  can also receive input from one or more sensors  68 . Non-limiting examples of sensors  68  that can be communicably coupled with the controller  14  include a temperature sensor and turbidity sensor to determine the soil load associated with a selected grouping of dishes, such as the dishes associated with a particular area of the treating chamber  20 . 
     Turning now to  FIG. 3 , a perspective view of the dishwasher  10  is illustrated. The tub  18 , which, by way of non-limiting example, can be injection molded of plastic, can include a bottom wall  70 , side walls  72 ,  74 , rear wall  76 , and a top wall  78 . The upper rack  24  can be coupled to the side walls  72 ,  74  for slidable movement relative thereto via support rails  82 . A utensil basket  84 , which contains a utensil  86 , can be positioned within the lower rack  26 , or at any other suitable location within the dishwasher  10 . Further, at least one of the upper rack  24  or the lower rack  26  can be vertically adjustable relative to the tub  18  via a rack height adjustment assembly  100 . In an exemplary embodiment, the rack height adjustment assembly  100  can include two rack height adjustment assemblies  100  provided at opposing sides of the upper rack  24  for vertically shifting the upper rack  24  between a first or lowered position and a second or raised position. While the upper rack  24  is illustrated herein as being vertically adjustable and including the rack height adjustment assembly  100 , it will be understood that the lower rack  26  can include the rack height adjustment assembly  100 , either instead of or in addition to the upper rack  24 . 
       FIG. 4  illustrates a perspective view of the rack height adjustment assembly  100  according to an embodiment of the present disclosure. The rack height adjustment assembly  100  can include an adjuster plate  120  that can be coupled with the support rail  82  such that it is at least partially withdrawable from the tub  18  along with the upper rack  24 , while also being vertically stationary relative to the tub  18 . The rack height adjustment assembly  100  includes a housing  152  comprising rack couplers  154  that allow the rack height adjustment assembly  100  to be coupled to the upper rack  24 . Any suitable number of rack couplers  154  can be included, and can be configured to couple the housing  152  to vertical or horizontal wires of the upper rack  24 , or to both the vertical and the horizontal wires. In an exemplary embodiment, the housing  152  is coupled to the upper rack  24  such that vertical movement relative to the upper rack  24  is not permitted, but horizontal movement along the upper rack  24  can optionally be permitted. An actuator  158  protrudes through an actuator opening  160  in an upper surface  156  of the housing  152 . 
       FIG. 5  illustrates a cross-sectional side view of the rack height adjustment assembly  100  corresponding to the raised position of the upper rack  24 . The actuator  158  includes an angled lower surface  136  that is positioned adjacent to an angled upper surface  134  of a locking lever  130 . The actuator  158  is slidably vertically movable relative to the housing  152  between an undepressed position, as shown in  FIG. 5 , and a depressed position shown in  FIG. 6 . The actuator  158  can be optionally provided with an actuator spring  138  that can serve as a biasing element and apply an upward pressure to the actuator  158 , such that the actuator spring  138  biases the actuator  158  toward the undepressed position. An actuator flange  106  bears against the actuator opening  160  when the actuator  158  is in the undepressed position to prevent further upward movement of the actuator  158 . 
     The locking lever  130  is pivotally movable relative to both the housing  152  and relative to the upper rack  24  about a pivot point  102 . In an exemplary embodiment, the pivot point  102  can be located near the vertical midpoint of the locking lever  130 . The locking lever  130  further comprises a lever flange  140 . The lever flange  140  protrudes horizontally outwardly from the locking lever  130  relative to the pivot point  102 . In an exemplary embodiment, the lever flange  140  extends outwardly towards an inner surface  142  of the housing  152 , the inner surface  142  being opposed to the adjuster plate  120 . The lever flange  140  can have some flexibility or compressibility relative to the locking lever  130 . In an exemplary embodiment, the lever flange  140  serves as a biasing element and exerts an outward force against the inner surface  142  of the housing  152 , which biases the locking lever  130  to a substantially vertical, non-pivoted position as shown in  FIG. 5 . 
     The locking lever  130  further comprises a catch end  132  that selectively engages with the adjuster plate  120  to define an engaging position and a release position of the locking lever  130 . Specifically, the adjuster plate includes an upper detent  124  and a lower detent  122 . As shown in  FIG. 5 , the catch end  132  of the locking lever  130  rests on top of the upper detent  124  of the adjuster plate  120 . The locking lever  130  is in the engaging position as the catch end  132  is engaged with the upper detent  124 . Further, when the catch end  132  rests on top of the upper detent  124 , the upper rack  24  is held in the raised position relative to the adjuster plate  120 . While the rack height adjustment assembly  100  is illustrated herein as including two detents, the upper and lower detents  124 ,  122 , corresponding to the raised and lowered position of the upper rack  24 , it will be understood that any suitable number of detents can be included to correspond to any suitable number of positions of the upper rack  24 . By way of non-limiting example, the adjuster plate  120  can be provided with three, four, or more detents such that the upper rack  24  can be selectively moved between three, four, or more pre-determined vertical positions relative to the tub  18 . 
       FIG. 6  illustrates the locking lever  130  in the release position relative to the adjuster plate  120 . The actuator  158  is in the depressed position, such that the actuator flange  106  has been moved downwardly until it contacts a housing ledge  104 , which prevents further downward movement of the actuator  158 . The lower angled surface  136  of the actuator  158  contacts and has moved downwardly against the upper angled surface  134  of the locking lever  130 . The locking lever  130  is shown in a pivoted position, such that the upper angled surface  134  has pivoted away from the actuator  158  and the catch end  132  is pivoted inwardly from the adjuster plate  120 , towards the inner surface  143 . The catch end  132  is not resting on the upper detent  124  and is not restricted from vertical movement by the adjuster plate  120 . In this release position, the rack height adjustment assembly  100 , and also the upper rack  24  to which the rack height adjustment assembly  100  is coupled, can be vertically movable relative to the adjuster plate  120  and relative to the tub  18 . 
       FIG. 7  illustrates the actuator  158  and the locking lever  130  in the same depressed position and release position, respectively, as shown in  FIG. 6 , but with the rack height adjustment assembly  100  and the upper rack  24  now in the lowered position relative to the adjuster plate  120 . When the rack height adjustment assembly  100  and the upper rack  24  are in the lowered position, a housing flange  150  contacts and rests on top of an upper surface  108  of the adjuster plate  120 . When the housing flange  150  rests on top of the upper surface  108 , further downward movement of the rack height adjustment assembly  100  and the upper rack  24  are prevented. 
       FIG. 8  illustrates the rack height adjustment assembly  100  and the upper rack  24  in the lowered position, with the actuator  158  in the undepressed position and the locking lever  130  in the non-pivoted position and in the engaging position relative to the adjuster plate  120 . In the engaging position with the upper rack  24  in the lowered position, the catch end  132  rests beneath the lower detent  122  of the adjuster plate  120 , preventing upward movement of the rack height adjustment assembly  100  and the upper rack  24 . The housing flange  150  resting on top of the upper surface  108  of the adjuster plate  120  prevents further downward movement, so the rack height adjustment assembly  100  and the upper rack  24  are locked from vertical movement in either the upward or the downward direction. The vertical distance between the housing flange  150  and the catch end  132  is selected to correspond to the vertical distance between the upper detent  124  and the lower detent  122  such that when the rack height adjustment assembly  100  is in the lowered position with the actuator  158  in the undepressed position and the locking lever in the engaging position, vertical movement is prohibited and the upper rack  24  is locked in place vertically in a stable manner such that vertical rattling movement is prevented. 
     Turning now to the operation of the rack height adjustment assembly  100 , a user can depress the actuator  158  in order to allow for selective vertical movement of the upper rack  24  between the lowered and raised positions within the tub  18 . In an exemplary embodiment, the upper rack  24  can include at least two rack height adjustment assemblies  100 , in opposing positions and corresponding to the side walls  72 ,  74  of the tub  18 . However, it will be understood that the upper rack  24  can be provided with only a single rack height adjustment assembly  100  on a single side of the upper rack  24 . The user can depress the actuator  158  by grasping the upper rack  24  and using either a thumb or a palm of a hand to depress the actuator  158 . 
     When the user has depressed the actuator  158  as shown in  FIGS. 6-7 , the lower angled surface  136  of the actuator  158  is pushed downward against the upper angled surface  134  of the locking lever  130 . The locking lever  130  is not vertically movable relative to the housing  152 , so the downward pressure applied by the lower angled surface  136  of the actuator  158  causes an upper portion of the locking lever  130 , specifically the upper angled surface  134  of the locking lever  130 , to pivot outwardly, away from the actuator  158 . As the locking lever  130  pivots about the pivot point  102 , the catch end  132  is pivoted in the opposite direction, away from the adjuster plate  120  and toward the inner surface  142 , causing the locking lever  130  to move from the engaging position to the release position relative to the adjuster plate  120 . At the same time, the pivoting of the locking lever  130 , particularly of the catch end  132  away from the adjuster plate  120 , causes the lever flange  140  to be compressed towards the catch end  132  against the inner surface  142 . When the actuator  158  is depressed and the locking lever  130  is in the release position, the user can then raise or lower the upper rack  24  to either the raised or the lowered position, respectively. 
     When the user has depressed the actuator  158 , released the locking lever  130 , and moved the upper rack  24  vertically to the desired position of either the raised position or the lowered position, the user can release the actuator  158  so that the actuator  158  returns to the undepressed position. The force provided by one or more biasing elements can cause the actuator  158  to return to the undepressed position when the user is no longer depressing the actuator  158 . For example, the lever flange  140  acts as a biasing element because of the compression force between the inner surface  142  and the lever flange  140 . The lever flange exerts an outward force against the inner surface  142  which biases the locking lever  130  to the non-pivoted position, which in turn biases the angled upper surface  134  toward the actuator  158 , creating an upward pressure against the angled lower surface  136  and urging the actuator  158  to return to the undepressed position. 
     Additionally, actuator spring  138  can provide further upward pressure to bias the actuator  158  to the undepressed position. In embodiments with the actuator spring  138  present, the actuator spring  138  can contribute to providing a more rapid and smooth return of the actuator  158  to the undepressed position. However, it will be understood that the actuator spring  138  is not required to be present within the rack height adjustment assembly  100 . In embodiments where the actuator spring  138  is not included, the biasing force provided by the lever flange  140  is sufficient to cause the actuator  158  to be returned to and biased to the undepressed position, regardless of whether the upper rack  24  is in the raised or the lowered position. In an exemplary embodiment, the actuator  158  can be formed from a low friction material in order to accommodate smooth movement of the actuator  158  from the depressed to the undepressed position when a user is no longer depressing the actuator  158 . Non-limiting examples of such a material include nylon or polyoxymethylene (POM). 
       FIGS. 9-10  illustrate another embodiment of the present disclosure comprising a rack height adjustment assembly  200 , which is similar to the first rack height adjustment assembly  100 , except for the structure and function of the upper angled surface  134  of the locking lever  130 . Therefore, elements in the rack height adjustment assembly  200  similar to those of the first rack height adjustment assembly  100  will be numbered with the prefix  200 , with it being understood that the description of the corresponding parts of the first embodiment applies to the second embodiment, unless otherwise noted. As the operation of the locking lever  230  relative to the adjuster plate  220  is essentially identical to that described with respect to the first embodiment in detail, the description of the operation will not be reiterated here. 
       FIG. 9  illustrates a cross-sectional view of the rack height adjustment assembly  200  with the actuator  258  in the undepressed position and the locking lever  230  in the non-pivoted position and in the engaging position with respect to the adjuster plate  220 . The lower angled surface  236  of the actuator  258  is adjacent to, but not deflecting, a flat spring head  234  of the locking lever  230 . The flat spring head  234  is similar to the angled upper surface  134  of the locking lever  130 , except that the angle of the flat spring head  234  can differ from that of the angled upper surface  134 , and the flat spring head  234  further includes a flat spring flange  210  that is at least partially deflectable. 
       FIG. 10  illustrates the rack height adjustment assembly  200  with the actuator  258  in the depressed position and the locking lever  230  in the pivoted position and in the release position with respect to the adjuster plate  220 . The actuator is depressed and applies a downward force to the flat spring head  234  and to the flat spring flange  210 , to at least partially deflect the flat spring flange  210 . Due to the deflection, the flat spring flange  210  thus applies an upward force against the angled lower surface  236  of the actuator  258 . 
     Turning now to the operation of the rack height adjustment assembly  200 , when the actuator  258  is depressed, the operation of the rack height adjustment assembly  200  is identical to that described for the first embodiment, with the depression of the actuator  258  resulting in pivoting of the locking lever  230  and causing the release of the catch end  232  from the adjuster plate  220 , moving the locking lever  230  from the engaging position to the release position such that a user can vertically adjust the upper rack  24  between the raised and the lowered position. When the user releases the actuator  258 , the lever flange  240  serves as a biasing element to bias the actuator  258  back to the undepressed position, as described previously. 
     In addition, the flat spring head  234  and the flat spring flange  210  act as an additional biasing element to urge the actuator  258  back to the undepressed position. Just as the actuator spring  138  can be optionally provided in the first embodiment, the flat spring head  234  and the flat spring flange  210  can be provided in the second embodiment to aid in returning the actuator  258  to the undepressed position. Because the downward movement of the actuator  258  exerts a downward force against the flat spring head  234  and at least partially deflects the flat spring flange  210 , the flat spring flange  210  also exerts an upward force against the actuator  258  as the flat spring flange  210  is biased to return to an original, undeflected position. When the depressing force applied by a user is no longer applied to the actuator  258 , the flat spring flange  210  exerts pressure against the angled lower surface  236  of the actuator  258 , providing additional biasing force to cause the actuator  258  to return to the undepressed position. 
     The embodiments described herein can be used to provide an adjustment assembly for the vertical height of a dish rack to allow selective vertical repositioning of the dish rack between at least a raised and a lowered position in a user-friendly and simple manner, while maintaining stability of the dish rack. The actuator allows for ease of use by a user and increased comfort by providing the option of using either a thumb or a palm of the hand to depress the actuator. In addition, it is easy for a user to tell when the actuator is fully depressed so the user knows it is possible and safe to then vertically adjust the dish rack. Further still, when the dish rack is vertically adjusted to the lowered position and is held in the engaging position, vertical movement in either the downward or the upward direction is prevented, resulting in a very stable hold of the dish rack. This can be ideal for transporting, shipping, delivering, and assembling of the dishwasher as the dish rack can be safely held in a secure manner, preventing rattling of parts or undesired movement of the dish rack during transport. 
     It will also be understood that various changes and/or modifications can be made without departing from the spirit of the present disclosure. By way of non-limiting example, although the present disclosure is described for use with a wire dish rack, it will be recognized that the rack height adjustment assembly can be employed with various rack constructions, including molded racks, such as racks molded of plastic. 
     To the extent not already described, the different features and structures of the various embodiments may be used in combination with each other as desired. That one feature may not be illustrated in all of the embodiments is not meant to be construed that it cannot be, but is done for brevity of description. Thus, the various features of the different embodiments may be mixed and matched as desired to form new embodiments, whether or not the new embodiments are expressly described. 
     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. 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.