Abstract:
A single piece tub support and frame for a dishwasher has a unitary support member that includes a pair of laterally spaced U-shaped upright end portions and an intermediate inverted U-shaped upright portion. The intermediate portion fits over the top and sides of the dishwasher tub rearwardly adjacent the front flange portion thereof. When the U-shaped end portions clear the bottom wall of the tub, they resiliently spring inward into supporting positions under the bottom wall. The unitary support member greatly reduces the number of components required, reduces manufacturing time and cost, and maintains the tub in its designed shape.

Description:
This application is a division of Ser. No. 09/994,246 filed on Nov. 26, 2001 now U.S. Pat. No. 6,666,531. 
    
    
     BACKGROUND OF THE INVENTION 
     The present invention relates to the field of dishwashers. More particularly, this invention relates to a single piece frame and support member for the tub of a dishwasher. 
     A typical dishwasher includes a tub having an open front leading to an interior washing compartment. A door pivotally mounts in a sealable manner over the front opening. Various means have been provided for supporting the tub on a floor or supporting surface. Heretofore tub frame and support means have typically included a plurality of separate component parts that must be welded or fastened together with mechanical fasteners, such as screws, rivets, or the like. Fabrication and assembly of these component parts requires considerable time and effort. It is desirable to minimize the number of component parts, movements, operations, and fasteners that are necessary to assemble the tub support frame, as well as to mount the tub and the door thereto. The component parts must also be assembled in a rather precise manner or distortion of the tub occurs. If the tub walls are not square with each other at the front opening, the door may have difficulty properly sealing the opening. 
     Therefore, a primary objective of the present invention is the provision of an improved frame and support system for a dishwasher tub. 
     A further objective of the present invention is the provision of a single piece tub frame and support member that requires no screws, rivets or other mechanical fasteners for its fabrication. 
     Another objective of the present invention is the provision of a single piece tub frame and support member that elevates the bottom wall of the tub and wraps around the top wall and opposite side walls of the tub to maintain squareness therebetween. 
     A further objective of the present invention is the provision of a method and means for dishwasher tub and support assembly that is economical, efficient in use, and which results in a reliable and durable assembly. 
     These and other objectives will be apparent from the drawings, as well as from the description and claims that follow. 
     SUMMARY OF THE INVENTION 
     The single piece tub support and frame for a dishwasher has a unitary support member that includes a pair of laterally spaced U-shaped upright end portions and an intermediate inverted U-shaped upright portion. The dishwasher tub attaches to the intermediate portion, which fits over the top and sides of the dishwasher tub rearwardly adjacent the front flange portion thereof. When the U-shaped end portions clear the bottom wall of the tub, they resiliently spring inward into supporting positions under the bottom wall. The unitary support member greatly reduces the number of components required, reduces manufacturing time and cost, and maintains the tub in its designed shape. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a right rear perspective view of a dishwasher tub mounted on the single piece support frame of the present invention. 
     FIG. 2 is a right side elevation view of the dishwasher tub and support frame of FIG.  1 . 
     FIG. 3 is a front elevation view of the dishwasher tub and support frame of FIG.  1 . 
     FIG. 4 is a perspective view of the unitary support frame of this invention. 
     FIG. 5 is a top plan view of the support frame of FIG.  3 . 
     FIG. 6 is a front elevation view of the support frame of FIG.  3 . 
     FIG. 7 is a right side elevation view of the support frame of FIG.  3 . 
     FIG. 8 is a cross-sectional view taken along line  8 — 8  in FIG.  5  and illustrates an embodiment wherein squire tubing forms the support frame. 
     FIG. 8A is cross-sectional view similar to FIG. 5, but shows an alternate embodiment, wherein a U-shaped channel member forms the support frame. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     FIGS. 1-3 illustrate a dishwasher tub and frame combination  10  that has a tub  12  supported by a single piece frame and support member  14  according to the present invention. The tub  12  includes a top wall  16 , opposite side walls  18 ,  20 , and a bottom wall  22 . The tub  12  has a back wall  23  and an open front  24 . In the preferred embodiment, the tub  12  is formed of lightweight stainless steel or molded from a plastic material, such as polypropylene, but the materials of the tub can be varied without detracting from the invention. 
     The tub  12  has a front flange portion  26  for receiving a portion of a door (not shown) that pivotally mounts to the frame and support member  14  at a pair of laterally spaced hinge brackets  28 . The front flange portion  26  has a substantially vertical faceplate  30 . A recessed substantially vertical surface  32  extends parallel to the faceplate  30  and partially around the perimeter of the open front  24  of the tub  12 . More particularly, the surface  32  extends along the top wall  16  and the side walls  18 ,  20 . A guide rib or flange  34  protrudes from the top wall  16  and the opposite side walls  18 ,  20  generally parallel to the recessed surface  32  and offset therefrom in the direction of the back tub wall  23 . Thus, a channel, slot or groove  36  is formed in the tub  12  between the guide rib or flange  34  and the front flange portion  26 . The front flange portion  26  and the groove  36  preferably extend perpendicular or square to the bottom wall  22  of the tub  12 . 
     Referring to FIGS. 4-8, a single piece of elongated bar stock forms the support member  14 . Preferably the bar stock is tubular and has a square transverse cross-section  38 , as shown in FIG. 8, or an open channel extending longitudinally therein and a U-shaped transverse cross-section  38 A, as shown in FIG.  8 A. The preferred materials include steel or aluminum alloys, but the materials can be varied without distracting from the invention. A forming operation results in the support member  14  having a plurality of bends that define several identifiable portions. 
     In general, the portions of the support member  14  include a pair of laterally spaced upright U-shaped end portions  40 L,  4 R and an intermediate portion  42  that has an inverted U-shape. The end portions  40 L,  40 R each have an upright front leg  44 L or  44 R, an upright rear leg  46 L or  46 R and a substantially horizontal bottom rail  48 L or  48 R respectively connecting the legs. The U-shaped end portions  40 L,  40 R preferably extend parallel to each other and reside in substantially vertical planes. 
     The intermediate portion  42  has a top rail  50  and side rails  52 L,  52 R. The exact profile of the inverted U-shaped intermediate portion  42  preferably closely conforms to the outer profile of the tub  12 . In the usual case of a rectangular tub, the top rail  50  extends horizontally and the rails  52 L,  52 R extend vertically. The side rails  52 L,  52 R are parallel to each other and perpendicular to the top rail  50 . 
     The side rails  52 L,  52 R are perpendicular to the U-shaped end portions  40 L,  40 R respectively. The top rail  50  is also perpendicular to the U-shaped end portions  40 L,  40 R. Thus, the intermediate portion  42  as a whole is perpendicular to and square with the end portions  40 L,  40 R. The lower ends of the vertical rails  52 L,  52 R can extend straight down and be directly joined to the front legs  44 L,  44 R respectively, or optional transition portions or rails  54 L,  54 R can angle downwardly and rearwardly to provide an indirect connection and recess the end portions  40 L,  40 R rearwardly from the rails  52 L,  52 R. 
     The unitary support member  14  has a plurality of holes  56 ,  58 ,  62 ,  64 ,  66 , that are preferably punched, pierced, or drilled during the forming operation. Longitudinally spaced holes  56  extend vertically through the bottom rails  48 L,  48 R of the U-shaped end portions  40 L,  40 R to receive threaded bolts  68  for leveling the tub  12 . Holes  58  extend through the intermediate portion  42  of the support member  14 . Holes  62  extend laterally into the lower ends of the vertical rails  52 L,  52 R, preferably just above the transition portions  54 L,  54 R when those portions exist. Holes  64  extend into the front legs  44 L,  44 R of the end portions  40 L,  40 R. Holes  66  extend into the rear legs  46 L,  46 R of the end portions  40 L,  40 R. 
     In use, the support member  14  attaches to the tub  12  in a quick, simple and easy manner. Although the support member  14  is substantially rigid, by design it has some resilient deformability. The worker can pull the end portions  40 L,  40 R or the lower ends of the intermediate portion  42  farther apart to slip them over the width of the top wall  16 . Then the worker moves the member  14  toward the front flange portion  26  and the bottom wall  22  of the tub  12  until the U-shaped end portions  40 L,  40 R clear the bottom wall  20 . At that point, the end portions  40 L,  40 R resiliently spring back inward into a supporting position under the bottom wall  20  or optional pads  69  attached thereto. The inverted U-shaped intermediate portion  42  will then be securely disposed in the groove  36 . 
     The worker secures the tub  12  to the support member  14  primarily by installing conventional fastening means  70 , such as screws in the holes  58 . A conventional door seal  72  (FIGS. 2 and 3) mounts on the recessed surface  32  and covers the heads of the screws  70 . Cabinet mounting brackets  74 ,  76  are also attached to the top rail  50  by the screws  70 . Door mounting brackets  28  attach to the lower ends of the intermediate portion  42  using holes  62 , just above the transition portions  54 L,  54 R. The optional angled transition portions  54 L,  54 R, also allow a toe plate  78  to be recessed rearwardly with respect to the front flange  26  of the dishwasher  10 . Conventional fastening means  80 , such as screws, attach the toe plate  78  at the holes  64  in the front legs  44 L,  44 R of the end portions  40 L,  40 R. An optional rear support cross member  82  laterally interconnects the rear legs  46 L,  46 R of the end portions  40 L,  40 R to provide additional rigidity to the frame and provide a means for securing the rear legs  46 L,  46 R to the pads  69 . 
     The single piece support member  14  can be formed in a single forming operation, thereby eliminating a number of machining operations for separate components parts and the sub-assembly thereof. Furthermore, the support member  14  has the added benefit of insuring the squareness of the tub  12  while supporting it. The front flange portion  26  of the tub is directly secured to the intermediate portion  42  of the support member  14 . By supporting the tub  12  at the front flange portion  26 , door seal problems have been substantially reduced or eliminated altogether. 
     Thus, it can be seen that the present invention at least satisfies its stated objectives. 
     In the drawings and specification, there has been set forth a preferred embodiment of the invention, and although specific terms are employed, these are used in a generic and a descriptive sense only and not for the purposes of limitations. Changes in the form and the proportional parts as well as in the substitution of equivalence are contemplated as circumstances may suggest or render expedient without departing from the spirit or scope of the invention as further defined in the following claims.