Abstract:
A dishwasher is provided, comprising a door pivotably attached to a body and having a counterbalance assembly coupled therebetween for facilitating pivoting of the door, wherein the counterbalance assembly includes a biasing member coupled to the body and serially engaged with a flexible element coupled to the door, and a guide member secured to the body and including a fixed arcuate member defining a first guide track, and a pulley rotatable about an axis and defining a second guide track, wherein the flexible element is at least partially wrapped about each of the fixed arcuate member and the pulley so as to serially engage the first and second guide tracks, and wherein the first guide track of the fixed arcuate member is offset from the second guide track of the pulley along the axis thereof.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
       [0001]    The present application is a continuation of U.S. application Ser. No. 11/869,911 filed Oct. 10, 2007, which claims priority to U.S. Provisional Application No. 60/916,013 filed May 4, 2007, the contents of which are hereby incorporated herein in their entirety by reference. 
     
    
     BACKGROUND OF THE INVENTION 
       [0002]    1. Field of the Invention 
         [0003]    Embodiments of the present invention relate to dishwashers and, more particularly, to a counterbalance assembly for a dishwasher door, and a method associated therewith. 
         [0004]    2. Description of Related Art 
         [0005]    A dishwasher typically includes a wash tub for containing the dishware to be washed, wherein the tub defines a front opening. The front opening is configured to be engaged by a door for closing/sealing the front opening. The door is typically hinged at the lower end thereof such that the upper end of the door can be pivoted downward so as to permit access to the interior of the tub. 
         [0006]    The dishwasher may include a device for balancing or counterbalancing the weight of the door, when opening and closing the door. For example, U.S. Pat. No. 5,226,706 to Tuller discloses an adjustable door balancing mechanism that includes a counterbalance spring. The counterbalance spring extends between the door and an adjustable bracket mounted to the tub support. The tension in the counterbalance spring may be varied by changing the position of the adjustable bracket. 
         [0007]    Despite these improvements in counterbalancing a dishwasher door, it would be advantageous for the door of the dishwasher to be balanced or counterbalanced so as to allow for smooth opening and closing of the door. That is, it may be advantageous to configure the door so as to prevent the door from inadvertently pivoting to the open or closed positions and/or to allow for the door to be maintained at various positions between the open and closed positions. 
         [0008]    Therefore, it would be desirable to provide a counterbalance assembly that facilitates opening and closing of a dishwasher door. In addition, it may be desirable to provide a counterbalance assembly that may be easily integrated with a dishwasher, is cost efficient, and may be readily adjusted. 
       BRIEF SUMMARY OF THE INVENTION 
       [0009]    The above and other needs may be met by embodiments of the present invention which, in one embodiment, provides a dishwasher comprising a door pivotably attached to a body and having a counterbalance assembly coupled therebetween for facilitating pivoting of the door. The counterbalance assembly includes a biasing member coupled to the body and serially engaged with a flexible element coupled to the door, and a guide member secured to the body and including a fixed arcuate member defining a first guide track and a pulley rotatable about an axis and defining a second guide track. The flexible element is at least partially wrapped about each of the fixed arcuate member and the pulley so as to serially engage the first and second guide tracks, wherein the first guide track of the fixed arcuate member is offset from the second guide track of the pulley along the axis thereof. 
         [0010]    Another aspect of the present invention comprises a method for facilitating pivoting of a door with respect to a body of a dishwasher. The method includes coupling a biasing member to the body, serially engaging the biasing member with a flexible element, and coupling the flexible element to the door. In addition, the method includes securing a guide member to the body, wherein the guide member includes a fixed arcuate member defining a first guide track and a pulley rotatable about an axis and defining a second guide track. The method further includes wrapping the flexible element at least partially about each of the fixed arcuate member and the pulley so as to serially engage the first and second guide tracks, wherein the first guide track of the fixed arcuate member is offset from the second guide track of the pulley along the axis thereof. 
         [0011]    Aspects of the present invention may provide significant advantages as further detailed herein. 
     
    
     
       BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING(S) 
         [0012]    Having thus described the invention in general terms, reference will now be made to the accompanying drawings, which are not necessarily drawn to scale, and wherein: 
           [0013]      FIG. 1  illustrates a partial view of a dishwasher including a door counterbalance assembly, with a dishwasher door in an open position, according to one embodiment of the present invention; 
           [0014]      FIG. 2  illustrates the counterbalance assembly of  FIG. 1  with the dishwasher door in a closed position; 
           [0015]      FIG. 3  is an enlarged view of the guide member shown in  FIG. 1 ; 
           [0016]      FIG. 4  depicts a side view of a guide member according to an embodiment of the present invention; 
           [0017]      FIG. 5  shows a front view of the guide member shown in  FIG. 4 ; 
           [0018]      FIG. 6  is a perspective view of the guide member shown in  FIG. 4 ; 
           [0019]      FIG. 7  is a perspective view of a guide member secured to a bracket according to one embodiment of the present invention; 
           [0020]      FIG. 8  is a partial perspective view of the guide member secured to the bracket shown in  FIG. 7 ; 
           [0021]      FIG. 9  is a cross-sectional view of a guide member secured to a body of a dishwasher according to an embodiment of the present invention; and 
           [0022]      FIG. 10  is an exploded view of a guide member and a bracket according to one embodiment of the present invention. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0023]    The present invention now will be described more fully hereinafter with reference to the accompanying drawings, in which some, but not all embodiments of the inventions are shown. Indeed, these inventions may be embodied in many different forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that this disclosure will satisfy applicable legal requirements. Like numbers refer to like elements throughout. 
         [0024]      FIGS. 1 and 2  illustrate a dishwasher  10  including a counterbalance assembly  12  according to one embodiment of the present invention. As explained in further detail below, the counterbalance assembly  12  facilitates pivoting of a door  14  with respect to a body  16  of the dishwasher  10 . In general, the counterbalance assembly  12  includes a biasing member  18 , a flexible element  20 , and a guide member  22  which cooperate to allow the door  14  to be smoothly pivoted between open and closed positions, as well as to be maintained in various positions between the open and closed positions. 
         [0025]    Although reference is made herein to a dishwasher  10 , it is understood that the counterbalance assembly  12  is adapted to be used with other devices where pivoting between a door and a body is necessary. For example, the counterbalance assembly  12  may be used with other kitchen appliances, such as a stove. In addition, although only one counterbalance assembly  12  is shown in  FIGS. 1 and 2 , it is understood that there may be a counterbalance assembly on both sides of the dishwasher  10 . 
         [0026]    As shown in  FIGS. 1 and 2 , the counterbalance assembly  12  includes a biasing member  18 , such as a tension spring or other elastic member made of a memory material. One end of the biasing member  18  is attached to a bracket  38 . In one embodiment, the biasing member  18  includes a hook  36  at its free end that is sized and configured to be positioned within one of a plurality of holes  39  defined in the bracket  38 . The bracket  38  is attached to the body  16  and, by positioning the hook  36  in different holes  39 , the tension on the biasing member  18  may be adjusted. 
         [0027]    The opposite end of the biasing member  18  is coupled to a flexible element  20 . In this regard, the biasing member  18  may include a hook  36  at its free end that is coupled to a coupling member  32  secured to one end of the flexible element  20 . Thus, the coupling member  32  may include a hole sized and configured to receive the hook  36  of the biasing member  18 . The opposite end of the flexible element  20  is coupled to a hinge bracket  28  with a coupling member  30 . In one embodiment, the coupling member  30  is configured to be positioned within a slot  29  defined in the hinge bracket  28 . The flexible element  20  may be, for example, an inelastic cord, such as a braided material. However, the flexible element  20  may be comprised of other materials, including elastic materials, capable of maintaining tension between the biasing member  18  and the hinge bracket  28  to facilitate opening and closing of the door  14 .  FIG. 3  illustrates that the slot  29  may include a bushing  15  and that the coupling member  30  may engage the slot and bushing. The bushing  15  may be a non-metallic material (e.g., polymeric) and may reduce squealing between the coupling member  30  and the slot  29  when the door  14  is opened and closed. The bushing  15  may correspond to the shape of the slot  29 , such as be U-shaped as shown in  FIG. 3 . 
         [0028]    The hinge bracket  28  and door  14  may pivot about a hinge pin  34 .  FIG. 1  illustrates the door  14  in an open position. Thus, in the open position, the portion of the hinge bracket  28  coupled to the flexible element  20  is generally vertically disposed, while the door  14  is generally horizontally disposed. The biasing member  18  is extended and, thus, tensioned from a relaxed position.  FIG. 2  depicts the door  14  in a closed position. In the closed position, the hinge bracket  28  is generally horizontally disposed, while the door  14  is generally vertically disposed. Moreover, the biasing member  18  contracts to a relaxed position, while the length of the flexible element  20  between the guide member  22  and the hinge bracket  28  is shortened when compared to the open position. 
         [0029]      FIGS. 1 and 2  also illustrate that the counterbalance assembly  12  includes a guide member  22  located proximate to the front of the dishwasher  10 . The guide member  22  includes a rotatable pulley  24  and an arcuate member  26 . The rotatable pulley  24  and the arcuate member  26  may be coupled together with a backing  25 , as shown in  FIGS. 4-6 .  FIGS. 9 and 10  show that the backing  25  may extend from the arcuate member  25  and include a coupling member  78  that extends outwardly from the backing to engage the pulley  24 . The pulley  24  is rotatable about the coupling member  78 . As shown in  FIG. 5 , the outer portions  46 ,  48  of the arcuate member  26  and pulley  24  may be generally circular in configuration. The arcuate member  26  may also include a frustroconical portion  50  extending between an inner portion  54  and the outer portion  46 , while the pulley  24  generally includes a frustroconical portion  52  extending between an inner portion  56  and the outer portion  48 , as shown, for example, in  FIG. 4 . 
         [0030]    In one embodiment, the guide member  22  may be secured to the bracket  27 , while the bracket  27  may be secured to the body  16  of the dishwasher, as shown in  FIGS. 1 ,  2  and  7 - 9 . In particular, a slot  31  is defined by a portion of the frustroconical portion  50  and inner portion  54  of the arcuate member  26 , while slots  33  are defined by the frustroconical portion  50  so as to extend therethrough. A slot  44  is defined by the inner portion  54  and the frustroconical portion  50  of the arcuate member  26 . As shown in  FIG. 7 , the slot  31  may engage with a clip  60  extending from the bracket  27 . In addition, the bracket  27  may also include a pair of clips  62  that engage respective slots  44  of the arcuate member  26 . As shown in  FIG. 8 , the arcuate member  26  may include a biasing clip  64  that biases outwardly to engage a hole  66  defined in the bracket  27 . The biasing clip  64  could be disengaged from the bracket  27 , for example, by accessing the clip  64  via slots  33  and biasing the ends of the clip  64  together. Furthermore,  FIG. 7  demonstrates that the bracket  27  may include an L-shaped member  68  that is configured to extend both adjacent to the backing  25  and perpendicularly under the body  16  of the dishwasher  10 . The bracket  27  may be configured to be secured to the body  16  using various techniques. For instance, at least a portion of the inner portion  54  of the arcuate member  26  and an arc-shaped member  76  of the bracket  27  could be configured to engage a slot  74  defined by the body  16 , as shown in  FIG. 9 . The pulley  24  may also include a hole  72  sized and configured to receive a fastener therethrough, which secures the pulley  24  to the body  16 , and also provides an axis of rotation (illustrated as axis B in  FIG. 4 ) for the pulley  24 .  FIG. 10  demonstrates that a fastener may be configured to extend though each of the hole  72  in the pulley  24 , the coupling member  78 , a hole  80  defined in the bracket  27 , and into the body  16 . 
         [0031]    In one embodiment, the arcuate member  26  of the guide member  22  is fixed, while the pulley  24  of the guide member  22  is rotatable. In addition, the arcuate member  26  and pulley  24  define respective guide tracks  40 ,  42 , as shown in  FIG. 4 . The guide tracks  40 ,  42  are generally semi-circular in configuration and are sized and configured to receive the flexible element  20 . The flexible element  20  is configured to extend in a serpentine manner about the arcuate member  26  and the lower pulley  24 , within the guide tracks  40 ,  42 . The arcuate member  26  provides friction with the flexible element  20  such that the door  14  can be maintained in any position between the fully opened and the fully closed positions. The rotatable lower pulley  24  guides the flexible element  20  and may be less prone to squealing (due to the rotating interaction with the flexible element) than, for example, instances in which the pulley or other lower member is fixed. 
         [0032]      FIG. 4  illustrates an additional aspect of the guide member  22 . In this regard, the guide track  40  of the fixed arcuate member  26  is laterally offset from the guide track  42  of the pulley  24 , with respect to the axis B about which the pulley  24  rotates. The offset distance is designated as reference A in  FIG. 4 . As such, the flexible element  20  engages the guide track  40  of the fixed arcuate member  26  at a different lateral position (i.e., spaced further outward from the body  16  of the dishwasher  10 ) than the guide track  42  of the pulley  24 . Thus, from the side view shown in  FIG. 4 , the flexible element  20  would extend obliquely between the pulley  24  and arcuate member  26 . The offset between the pulley  24  and arcuate member  26  may allow the biasing member  18  to be disposed further inward under the body  16  of the dishwasher  10 , while the hinge bracket  28  may be spaced laterally outward therefrom to clear the sides of the body  16 . 
         [0033]    It is understood that the exemplary guide member  22  shown in  FIGS. 1-10  is not meant to be limiting and may be various sizes and configurations in additional aspects of the present invention. For example, the arcuate member  26  and pulley  24  may be independently secured to the body  16  such that the backing  25  is unnecessary. Similarly, different techniques may be employed to secure the pulley  24  and arcuate member  26  to the body  16 , such as with fasteners, clips, rivets, adhesives, and the like. Moreover, the arcuate member  26  may be other configurations than circular, such as semi-circular, and still provide a semi-circular guide track  40  for the flexible element  20  to interact therewith. The pulley  24  and arcuate member  26  may be different sizes to accommodate different dishwashers  10  and flexible elements  20 . For instance, the guide tracks  40 ,  42  may be other sizes and configurations depending on the size and configuration of the flexible element. Furthermore, the offset distance A may be varied in order to achieve a desired tension in the flexible element  20  between the pulley  24  and the arcuate member  26  for opening and closing the door  14  (e.g., increasing the offset distance A for a heavier door  14 ). In still other instances, the positions of the pulley  24  and the arcuate member  26  may be reversed, or the guide member  22  may be disposed and engaged with the dishwasher  10  such that the pulley  24  and arcuate member  26  are non-vertically oriented. Additionally, it may be desirable for certain applications to fix the pulley  24  and allow the arcuate member  26  to rotate, fix both the pulley  24  and arcuate member  26 , or allow both the pulley  24  and arcuate member  26  to rotate. 
         [0034]    Many modifications and other embodiments of the inventions set forth herein will come to mind to one skilled in the art to which these inventions pertain having the benefit of the teachings presented in the foregoing descriptions and the associated drawings. Therefore, it is to be understood that the inventions are not to be limited to the specific embodiments disclosed and that modifications and other embodiments are intended to be included within the scope of the appended claims. Although specific terms are employed herein, they are used in a generic and descriptive sense only and not for purposes of limitation.