Abstract:
A refrigerator cabinet includes a shell having first and second laterally spaced, upstanding side walls that are interconnected by a top wall, each of the walls includes an in-turned front edge portion defining a liner receiving cavity. The shell further includes a mullion bar, which partitions the shell into first and second liner cavities, and a base member. Both the mullion bar and base member have respective liner receiving portions. With this arrangement, first and second liners are adapted to be inserted into their respective cavities and flexed such that three sides are inserted into the liner receiving cavities, while the remaining side is positioned against a land of the mullion bar or base member. Once in place, the liners are secured through a mullion bar cover and a base member cover. This construction combines the benefits of a front-load process with that of a flex-load process, lowering assembly time without the need to reinforce the liner.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
   This application represents a divisional application of U.S. patent application Ser. No. 10/624,545 filed Jul. 23, 2003 now U.S. Pat. No. 7,108,341. 

   BACKGROUND OF THE INVENTION 
   1. Field of the Invention 
   The present invention pertains to the art of refrigerators and, more particularly, to the structure and assembly of a refrigerator cabinet. 
   2. Discussion of the Prior Art 
   In general, it is known to construct a refrigerator by initially forming a shell and then inserting a liner portion therein. The prior art teaches a variety of methods for engaging the liner portion with the shell. These methods can be best described as slide-in, front-load, flex-load and combinations thereof. 
   In connection with a top mount refrigerator, the slide-in method initially positions the shell in a matter that provides access to a bottom portion. The liner portion is then inserted through the bottom portion and into place within the shell, thus forming a freezer compartment. Typically in top mount refrigerators, at this point, a mullion member is positioned such that the shell is partitioned into upper and lower cavities. After the mullion member is secured, a second liner is inserted through the bottom portion to form a fresh food compartment. While this method has proven effective over the years, it generally requires more production space due to the overall size of the refrigerator and the need to position the unit providing access to the bottom. 
   Another known manufacturing process is the front load method. Using this process, a shell is constructed having a flange extending about a periphery of the shell which forms a receiving cavity opening towards a front of the refrigerator shell. A liner, having an outwardly extending projecting edge portion leading to an in-turned rim portion, is then inserted into the shell wherein the in-turned rim portion is positioned in the receiving cavity to position the liner in place. At this point, a plurality of trim pieces are secured to the shell such that the liner is held in place for the next processing step. While also an effective method, the need for the trim pieces adds to the overall cost of production. 
   A variation of the front-load method, the flex-load process, eliminates the need for the additional trim pieces required to hold the liner in place. Using this process, a shell is constructed having an in-turned flange leading to a return flange which collectively define a laterally opening receiving cavity. In contrast to the front-load liner, the flex-load liner includes an outwardly projecting edge. To form the cabinet, the liner is inserted into the shell, and flexed or deformed laterally inwardly to allow the projecting edge to be positioned in the receiving cavity. A drawback with this process exists in that the liner must be tough enough to flex without tearing or developing cracks. That is, the liner must be formed such that portions of the liner which undergo stress during deformation must be strengthened. Typically, a refrigerator liner is a paper thin, thermoformed plastic tub-like member. Therefore, excessive handling or deformation during construction of the cabinet can result in cracking and subsequent failure of the liner. In most cases, the failure is not realized until after insulation is added. If insulation is added to a defective or failed liner, the liner could burst thereby requiring the shell to be discarded. 
   Based on the above, there exists a need in the art for a method of constructing a refrigerator cabinet which combines the benefits of front-loading with those derived from flex-loading. More specifically, there exists a need for a liner adapted to flex into portions of the shell, while remaining edge portions of the liner are initially exposed and later covered by a trim piece. 
   SUMMARY OF THE INVENTION 
   The present invention is directed to a refrigerator cabinet assembly including a shell having first and second laterally spaced upstanding side walls that are interconnected by a top wall. Specifically, each of the side and top walls include front edge portions being in-turned to form respective front face portions of the shell. The front face portions lead to a return flange that defines a liner rim receiving cavity opening laterally inward of the shell. 
   The cabinet assembly further includes a base member interconnected with the first and second side walls and preferably forming a face plate. In addition, a mullion bar is interconnected with and secured to the side walls at a position spaced from the base member. With this arrangement the mullion bar partitions the shell into first and second liner receiving portions. In accordance with a preferred form of the invention, the mullion bar includes first and second horizontally extending shoulder portions which, in turn, define first and second liner rim receiving lands. 
   With this construction, first and second liners having outwardly projecting edge portions are respectively inserted into the first and second liner receiving portions. Specifically, the outwardly projecting edge portions define liner peripheral rims which are adapted to be inserted into the liner rim receiving cavities disposed about the shell. More specifically, the first liner is inserted into the first liner receiving portion establishing a freezer compartment, with the first liner being flexed so that upper and side peripheral rims are engaged with the rim receiving cavities on the shell and then released so that a bottom liner edge portion rests on the mullion bar. Similarly, the second liner is inserted into the second liner receiving portion establishing a fresh food compartment. That is, the second liner is flexed such that side edge portions engage with the liner receiving cavities on the shell and, upon being released, upper and lower edge portion of the liner rest in respective receiving portions on the mullion bar and base member. 
   Once the first and second liners are in place, a mullion bar cover is secured to the mullion bar such that the lower edge of the first liner and the upper edge of the second liner are held in place. The lower edge of the second liner is then covered by a base plate cover so that the second liner is held in place for subsequent manufacturing steps. Additional objects, features and advantages of the present invention will become more readily apparent from the following detailed description of a preferred embodiment when taken in conjunction with the drawings wherein like reference numerals refer to corresponding parts in the several views. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  is an exploded view of a top mount flex load refrigerator cabinet constructed in accordance with the present invention; 
       FIG. 2  is a front view of a shell of the refrigerator cabinet of the present invention; 
       FIG. 3  is a partial cross-sectional view of a front face portion of the refrigerator of the present invention with a liner installed; 
       FIG. 4  is a partial cross-sectional view of a mullion bar of the refrigerator of  FIG. 2  depicting a lower liner installed; 
       FIG. 5  is a partial top view of a corner of the mullion bar of  FIG. 4 , depicting a hinge tapping plate interconnecting the mullion bar to the refrigerator cabinet; 
       FIG. 6  is a partial cross-sectional view of the base portion of  FIG. 1  depicting the lower liner arranged in a receiving land; 
       FIG. 7  is a partial bottom view of the base portion of  FIG. 6 , depicting a hinge tapping plate interconnecting the base portion to the cabinet; 
       FIG. 8  is a partial top view of a reinforced mullion bar arrangement constructed in accordance with a preferred embodiment of the present invention; and 
       FIG. 9  is a partial bottom view of a reinforced base portion arrangement employed in the embodiment of  FIG. 8 . 
   

   DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
   With initial reference to  FIGS. 1 and 2 , a refrigerated cabinet shell constructed in accordance with the present invention is generally indicated at  2 . Cabinet shell  2  includes a first side wall  6 , a second side wall  7 , a top wall  9 , and a rear wall  11 . Preferably, side walls  6  and  7  and top wall  9  are integrally formed from bending a single piece of sheet metal, with side walls  6  and  7  being arranged in an upstanding, substantially parallel manner and are interconnected by top wall  9 . Rear wall  11  is also preferably formed from sheet metal and is separately secured to side walls  6  and  7 , as well as top wall  9 . 
   Front edge portions of each of the side walls  6  and  7  and top wall  9  are bent inwardly so as to define respective front face portions  14 - 16 . Each of the front face portions  14 - 16  terminates in respective return flanges  18 - 20  (also see  FIG. 3 ). Although the specific structure of return flanges  18 - 20  will be discussed more fully below, each return flange defines, at least in part, a respective liner receiving cavity  22 - 24  one of which is shown in  FIG. 3 . As best shown in  FIG. 2 , a base portion  29  interconnects lower portions of front face portions  14  and  15  of upstanding side walls  6  and  7 . Preferably, base portion  29  is secured to side walls  6  and  7  using a pierce riveting process, although other methods such as spot welding, and mechanical fasteners are equally acceptable. As will be described more fully below, base portion  29  includes an in-turned liner received ledge  30  extending horizontally along a top edge of base portion  29 . A cover or kick plate  32  ( FIG. 6 ) is further arranged over base portion  29  to act as a finish covering. 
   As will be explained hereinafter, shell  2  is sub-divided into upper and lower portions  35  and  36  so as to define freezer and fresh food sections. Towards that end, a mullion bar  38  interconnects side walls  6  and  7  at a defined distance from top wall  9 . In a manner similar to that used to secure base portion  29 , mullion bar  38  is fastened to side walls  6  and  7  using a pierce riveting process. In accordance with a preferred form of the present invention, an upper liner receiving land  40  extends horizontally across an upper edge portion of mullion bar  38 . Likewise, a lower liner receiving land  42  extends horizontally across a lower edge portion of mullion bar  38 . In a manner similar to base portion  29 , a mullion bar cover portion  44  ( FIG. 4 ) serves as a finish covering for mullion bar  38 . Preferably, base cover  32  and mullion cover  44  are attached to base portion  29  and mullion bar  38  respectively, with adhesive. In a manner known in the art, a yoder tube  46  is arranged behind mullion bar  38 . Yoder tube  46  minimizes the development of condensation by providing a minimal amount of heat which radiates through to an outer surface of mullion bar  38 . 
   As will be set forth more fully below, the construction of cabinet shell  2  enables upper liner receiving portion  35  to receive an upper or freezer compartment liner  57 . In the preferred arrangement, upper liner  57  is constructed from thermoformed plastic and includes an outwardly projecting edge portion  59 . In an analogous manner, lower liner receiving portion  36  is adapted to receive a lower or fresh food compartment liner  62 , which is similar in construction to freezer compartment liner  57  and includes an outwardly projecting edge portion  64 . 
   With this arrangement, cabinet shell  2  defines upper corners  74  and  75  at the junction between respective side walls  6  and  7  and top wall  9 . Each upper corner  74 ,  75  defines a respective slot  76 ,  77  at front face portions  14 - 16 . In a preferred form of the invention, corner reinforcing braces  79  and  80  are adhesively secured to inner surfaces of upper corners  74  and  75  to provide an additional measure of structural stability to shell  2 . Shell  2  further includes additional reinforcing structure in the form of mullion bar attachment brackets  85  and  86  which extend between side walls  6  and  7  and mullion bar  38 , and base plate attachment brackets  93  and  94  that extends between side walls  6  and  7  and base portion  29 . 
   In addition to securing mullion bar  38  and base portion  29 , attachment brackets  85 - 86  and  93 - 94  can be used to aide in securing hinges and support legs to cabinet shell  2 . Specifically, attachment brackets  85 - 86  and  93 - 94  can be used as tapping plates to secure hinge members (not shown) to accommodate associated doors (not shown). More specifically, base portion attachment brackets  93 - 94  include leg mounting flanges  96  and  97 . In a manner known in the art, leg mounting flanges  96  and  97  include a threaded bore  98  (see  FIG. 7 ) adapted to receive a respective leg member (not shown). Actually, a plurality of leg members extend from leg mounting flanges  96  and  97  at front and rear portions of cabinet shell  2 , along side walls  6  and  7 . In any event, the various leg members are preferably, vertically adjustable to also act as levelers for cabinet shell  2 . Such type of leg leveler arrangements are widely known in the art of appliances, including ranges and refrigerators, such that the leveling function of the leg members does not form part of the present invention. 
   Reference will now be made to  FIG. 3  in describing the specific structure of return flanges  18 - 20 . Since the structure of each return flange  18 - 20  is identical, a detailed description of return flange  19  will be made and it is to be understood that return flanges  18  and  20  have commensurate structure. Return flange  19  includes a first section  120  that, in the preferred embodiment, is formed as an in-turned, folded back portion arranged generally parallel to face portion  15 . First section  120  leads to a second section  122  that curves inward. Thereafter, second section  122  leads to a third or return section  124 . Collectively, this structure defines liner receiving cavity  23 . A fourth, angled section  126  extends from third section  124  which, as will be described more fully below, enhances the insertion of a respective liner edge portion  59  or  64 . 
   Reference will now be made to  FIG. 4  in describing the specific structure of liner receiving lands  40  and  42  arranged along mullion bar  38 . Since the structure of each liner receiving land is identical, a detailed description of receiving land  40  will be made and it is to be understood that receiving land  41  has commensurate structure. In accordance with a preferred embodiment, receiving land  40  includes a first segment  135  extending inwardly towards rear wall  11 , generally perpendicular to the main body (not separately labeled) of mullion bar  38 . First segment  135  leads to a second, angled segment  137  which, in turn, leads to a third, preferably tapered and angled segment  139 . 
   In accordance with one preferred embodiment of the present invention, mullion bar  38  extends laterally across cabinet shell  4  and interconnects side walls  6  and  7  through mullion brackets  85  and  86 . As each connection between mullion bar  38  and brackets  85  and  86  is identical, a detailed description of the connection formed by bracket  86  will be described. As best shown in  FIG. 5 , mullion bracket  86  includes a first portion  160  secured to mullion bar  38  and a second portion  162  secured to a rear surface of front face portion  15 . In a preferred arrangement, mullion bar  38  is secured to brackets  85  and  86  with a pierce riveting process, and likewise brackets  85  and  86  to front face portions  15  and  16 . While pierce riveting is disclosed as the preferred method of attachment, it should be understood that other methods, such as welding or the use of mechanical fasteners, are equally acceptable. 
   Preferably, first and second portions  160  and  162  are interconnected through a curved portion  164  which spans a gap  170  arranged between mullion bar  38  and face portion  15 . In order to provide a flat surface, so that mullion bracket  86  will lie flush against an inner surface of face portion  15 , return flange  19  is interrupted at the mullion bar attachment point. More specifically, return flange  19  terminates at first section  120 . At this point, mullion bar  38  is secured to bracket  86 , spaced from face portion  15 . With this arrangement, gap  170  provides clearance to receive an in-turned terminated portion  174  of mullion cover  44 . 
   Reference will now be made to  FIG. 6  in describing a preferred arrangement of liner receiving ledge  30  which extends along the upper edge of base portion  29 . As shown, liner receiving ledge  30  includes a first, in-turned section  182  extending from base portion  29  leading to a second section  184  which extends vertically, substantially parallel to base portion  29 . A third section  186  of receiving ledge  30  extends from second section  184  curving and extending inward of cabinet shell  2 . Third section  186  leads to a fourth section  190  that extends vertically, substantially parallel to base portion  29 . With this arrangement, liner receiving ledge  30  appears as a series of steps extending from base portion  29  and providing at least one surface (not separately labeled) onto which projecting rim  64  of liner  62  can rest. 
   In a manner similar to that described above with respect to mullion bar  38 , base portion  29  extends laterally across and interconnects side walls  6  and  7  through respective base portion brackets  93  and  94 . As each connection between base portion  29  and brackets  93  and  94  is identical, a detailed description of the connection formed by bracket  94  will be described. As best shown in  FIG. 7 , base portion bracket  94  includes a first portion  197  which is secured to base portion  29  and a second portion  198  secured to a rear surface of front face portion  15 . Preferably, first and second portions  197  and  198  are interconnected through a curved portion  200  which spans a gap  202  established between base portion  29  and front face portion  15 . 
   In a preferred form of the invention, as described above, leg mounting section  97  extends from second portion  198 , thus providing the necessary support for legs (not shown). Likewise, in a manner similar to that described above with respect to mullion bar  38 , in order to provide a flat surface so that base portion attachment bracket  94  can lie flush against an inner surface of front face portion  15 , return flange  19  is interrupted at the base portion attachment point. More specifically, return flange  19  terminates at first section  208 . Base portion  29  is then secured to bracket  94 , spaced from front face portion  15 . With this arrangement, gap  202  provides clearance to receive an in-turned terminal portion  210  of base cover  32 . 
   The above described construction allows first and second liners  57  and  62  to be advantageously inserted into respective first and second liner receiving portions  35  and  36 . In accordance with the most preferred embodiment of the invention, first liner  57  is initially placed in first liner receiving portion  35 . At this point, first liner  57  is flexed such that top and side portions of projecting rim  59  engage the respective liner receiving cavities  22 - 24 . Once each of the respective top and side portions have engaged a respective receiving cavity  22 - 24 , first liner  57  is released such that bottom edge portion of projecting rim  57  rests in upper liner receiving land  40  extending across mullion bar  38 . 
   In a similar manner, second liner  62  is inserted into second liner receiving portion  36  and flexed such that each respective side portion of projecting rim  64  engages respective liner receiving cavities  22  and  23  extending along side walls  6  and  7 . Second liner  62  is then released such that upper edge of projecting rim  64  comes to rest against lower liner receiving land  42  ( FIG. 4 ), and the lower edge of projecting rim  64  rests upon liner receiving ledge  30  ( FIG. 6 ). In this manner, first and second liners  57  and  62  can be constructed in a manner which eliminates the need for reinforcing particular areas of the liners in order to accommodate the stresses caused by flexing the liners to place the peripheral rim portions thereof into the respective receiving cavities. Once each of the first and second liners  57  and  62  are so positioned, mullion cover  44  and base cover  32  are secured to mullion bar  38  and base portion  29  respectively. Preferably, mullion cover  44  and base cover  32  are secured with adhesive, however other means, such as double-sided tape and the like, are also acceptable. Finally, while significant gaps are depicted between mullion cover  44 , base cover  32 , and the respective projecting rims  59  and  64  for clarity purposes, actually these components are essentially in abutting relationship prior to an injection foaming process. 
   The above described embodiment is considered to be generally designed for light-duty applications, e.g. refrigerators under 20 cubic feet in size, wherein extra horizontal stability is not generally required. In heavier duty applications, e.g. for larger units having storage on the doors and the like, reinforcing structure is preferably added to mullion bar  38  and base portion  29 . 
   Now referring to  FIG. 8  depicting another embodiment of the present invention, a mullion reinforcing cross-brace  215  is secured to mullion bar  38 . Mullion bar reinforcing cross-brace  215  increases the stiffness and, by extension, the horizontal stability of cabinet shell  2  to accommodate, in part, larger doors having extensive storage space. Preferably, cross-brace  215  is secured to front face portion  15  of side wall  7  through a bridge element  217 . Since cross-brace  215  increases the thickness of mullion bar  38 , a spacer element  219  is secured to front face portion  15  providing an attachment point for bridge element  217 . In a preferred form of the invention, cross-brace  215  is secured to bridge element  217  with a pierce riveting process. Likewise, bridge element  217  and spacer element  219  are secured to front face portion  15  through a similar process. However, as with brackets  85  and  86  and  93  and  94 , other attachment methods, such as welding and the use of mechanical fasteners, are equally acceptable. 
   In order to further strengthen cabinet shell  2 , a similar stiffener arrangement is also incorporated into base portion  29 . As best seen in  FIG. 9 , a base portion reinforcing brace  222  is secured to base portion  29 . In a manner similar to that described above, base portion reinforcing brace  222  increases the horizontal stability of shell  2 . Base portion reinforcing brace  222  is secured to front face portion  15  through a bridge element  224  and associated spacer element  225 . More specifically, bridge element  224  included a leg mount  97   a  having an associated threaded bore  98   a  adapted to interconnect with an associated leg member (not shown). Using a process similar to that set forth above, base portion reinforcing brace  222  is secured to base portion  29  through a pierce riveting process. Likewise, bridge element  224  and spacer  225  are attached to front face portion  15  in the same manner. It should be understood that, having described the particular reinforcing elements and attachment thereof to front face portion  15 , identical structure and processes are used to secure corresponding reinforcing elements to opposing front face portion  14 . 
   Although described with reference to preferred embodiments of the invention, it should be readily understood that various changes and/or modifications can be made to the invention without departing from the spirit thereof. For instance, the particular method of attachment of mullion cover and base cover can be varied without departing from the spirit of the invention. Additionally, although shown and described with reference to a top mount refrigerator, a similar structure and method can be used to assemble a side-by-side unit. In general, the invention is only intended to be limited by the scope of the following claims.