US20080180011A1

US20080180011A1 - Refrigerator door assembly

Info

Publication number: US20080180011A1
Application number: US11/700,004
Authority: US
Inventors: Scott W. Leimkuehler; Kevin Lee Noel; David J. Olberding
Original assignee: Maytag Corp
Current assignee: Maytag Corp
Priority date: 2007-01-31
Filing date: 2007-01-31
Publication date: 2008-07-31
Also published as: MX2008001497A

Abstract

A refrigerator includes a cabinet having a frontal opening. A door assembly is pivotally mounted across the frontal opening of the cabinet to provide access to food items stored therein. The door assembly includes a door pan having a front face portion, as well as a top panel portion, a bottom panel portion and opposing side panel portions that establish a plurality of corners. A bracket is affixed each of the plurality of corners to provide support for the door pan, with each bracket being clinched at a plurality of locations to secure the bracket in place. By affixing the bracket through clinching, the need for a subsequent finishing step is eliminated.

Description

BACKGROUND OF THE INVENTION

1. Field of the Invention
The present invention pertains to the art of refrigerators and, more particularly, to a refrigerator door assembly provided with reinforcing corner brackets that are secured to a door pan portion of the refrigerator door assembly through a clinching process.
2. Discussion of the Prior Art
In constructing a refrigerator, it is highly desirable to minimize the weight of a cabinet shell portion to reduce manufacturing, transportation and additional associated costs, yet it is imperative that the cabinet be structurally sound in order to counteract loads exerted thereon without deforming. Mainly due to cost efficiencies and flexibility in workmanship, it has been commonplace to utilize sheet metal in the forming of most refrigerator cabinets on the market today. Since sheet metal is thin and rather high loads tend to be concentrated on the shell, particularly by the opening and closing of a weighted down refrigerator door, a fair amount of effort has been applied in this art to provide reinforcement for such a refrigerator cabinet shell. Of course, an additional important concern is the ease of assembly, as well as the overall aesthetics, of the cabinet as a whole.
With this in mind, it has been proposed to form the side and top walls of a refrigerator cabinet shell out of a single piece of bent sheet metal and then to attach thereto rear and bottom walls. That is, the side walls and top wall are integrally formed by bending a single piece of sheet metal forming a plurality of corner regions. The cabinet is fitted with a liner and then foam insulation is added which, once cured, provides both structural support and thermal retention. Equally important as the fabrication of the cabinet is the fabrication of a door assembly for the refrigerator. Without proper support, stresses created by food and other items supported on door shelves will cause the door to bend, warp or sag. This is particularly true with side-by-side refrigerators which provide an abundance of shelf space on the doors.
Refrigerator doors are constructed in a manner similar to that describe above for refrigerator cabinets. In general, a door pan is formed by bending a sheet of metal to form a front face portion and top, bottom and opposing side panel portions that define at least four corner regions. In order to provide strength, particularly on a hinged side of the door, portions of the opposing side panel portions are folded over onto respective ones of the top and bottom panel portions forming an overlap. The overlap occurs at each of the four corner portions and is further reinforced by welding. However, as the size and weight of items supported on refrigerator doors have increased, the door and, in particular, the hinge side of the door required additional reinforcement. Thus, manufacturers have proposed adding hinge-side corner brackets to the door pan. Unfortunately, the presence of the overlap prevents the corner bracket from properly nesting in the corner. Therefore, in order to accommodate the bracket, the overlap is cut out and removed from the hinge side of the door. Once removed, the corner bracket is positioned and welded to the door pan.
Unfortunately, removing the overlap exposes metal surfaces of the door pan. As exposed metal surfaces will, over time, rust, removing the overlap eliminates any possibility of using pre-painted or pre-finished material other than stainless steel. Likewise, welding the corner brackets to the door pan in combination with pre-painted material is undesirable. In particular, the heat generated during the welding process will damage the finish applied to the door pan. Therefore, when brackets are attached to the door pan, an additional manufacturing step is required. More specifically, once the brackets are affixed to the door pan, a subsequent painting or finishing process is needed to complete the door. While other methods of joining, such as rivets, screws and the like, do not require heat, they remain noticeable and thus require a cosmetic cover to ensure a seamless, finished appearance.
In the art, corner brackets have only been employed on the hinge side of the door. While this process certainly reduces the number of component and steps required to fabricate a door, assembly lines required constant modification in order to make right hand and left hand doors. That is, first the assembly line is configured for a run of, for example, right hand doors. Once a series of right hand doors are complete, the line is reconfigured to run left hand doors. With this configuration, the remainder of the assembly process is put on hold until enough right and left hand doors are stockpiled. Obviously, this process adds to overall assembly time. In the highly competitive field of home appliances, eliminating manufacturing steps and reducing assembly time is very desirable.
Based on the above, there exists a need in the art for a refrigerator door assembly that can be manufactured using a minimal number of processing steps. More specifically, there exists a need for a door assembly that can be reinforced without using a process that would damage a pre-existing exterior finish or require cosmetic covers to conceal unfinished portions of a door pan.

SUMMARY OF THE INVENTION

The present invention is directed to a refrigerator including a cabinet having first and second laterally spaced upstanding side walls that are interconnected by a top wall to form a frontal opening. In addition, the refrigerator includes a door assembly pivotally mounted relative to the cabinet for closing the frontal opening. The door assembly includes a door pan having a front face portion, as well as a top panel portion, a bottom panel portion and opposing side panel portions that collectively establish a plurality of corners. An end section of at least one of the opposing side panel portions is provided with an upper, in-turned flange that is substantially co-planar with the top panel portion. The upper, in-turned flange and the top panel portion are formed so as to collectively define a hinge opening that establishes a hinge corner. In order to provide structural support for the door assembly, a corner bracket is affixed to the door pan at the hinge corner. In accordance with a preferred form of the invention, the corner bracket includes a first leg portion that extends to a second, substantially perpendicular, leg portion. When installed on the door pan, the first leg portion extends along the top panel portion and the second leg portion extends along one of the side panel portions. In order to provide a receiving point for a hinge, the first leg portion of the corner bracket is provided with an opening that aligns with the hinge opening. In this manner, a hinge can be positioned at the hinge corner to define a pivot axis for the door.
In accordance with the invention, the corner bracket is fixedly secured at the hinge corner using a mechanical clinching process. More specifically, a series of mechanical clinches are used to join the corner bracket to each of the top panel portion and the side panel portion of the door pan. As clinching is a process of forming a mechanical bond between at least two materials without the use of heat, the absence of heat advantageously enables the use of a pre-painted or pre-finished material in the construction of the door pan. In this manner, additional painting or finishing process is eliminated from the production line. Moreover, both pre-painted and stainless steel doors can be manufactured on the same assembly line. In further accordance with the most preferred form of the invention, a corner bracket is secured to each of the plurality of corners of the door pan. In this manner, not only is the door pan further strengthened, but right and left hand doors can be run on the same assembly line at the same time thereby making refrigerator fabrication a more seamless and efficient process.
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 a partial left perspective view if a side-by-side refrigerator incorporating a door assembly constructed in accordance with the present invention;

FIG. 2 is a perspective view of a door pan portion of the door assembly constructed in accordance with the present invention;

FIG. 3 is an enlarged detailed view of a corner portion of the door pan of FIG. 2, illustrating a corner bracket secured to the door pan n accordance with the present invention;

FIG. 4 is an exploded detailed view of the corner portion of FIG. 3, with the corner bracket removed from the door pan; and

FIG. 5 is an enlarged cross-sectional view of a section of the corner portion of FIG. 3, illustrating a clinch joint employed to secure the corner bracket to the door pan.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

With initial reference to FIG. 1, a side-by-side refrigerator is generally indicated at 2. Refrigerator 2 includes a cabinet shell 4 including a pair of laterally spaced side walls 6 and 7 interconnected by a top wall 8. Cabinet 4 defines a freezer compartment 10 and a fresh food compartment 12 that are separated by an intermediate wall or mullion 14. In a manner known in the art, refrigerator 2 includes a freezer door assembly 18 that selectively provides access to freezer compartment 10 and a fresh food door assembly 20 that provides access to fresh food compartment 12. Towards that end, each door assembly 18 and 20 is provided with a corresponding handle 23 and 24. In a manner also known in the art, freezer door assembly 18 is provided with an ice/water dispensing assembly 28 that enables a consumer to retrieve ice and/or water from the front of refrigerator 2. Both freezer door assembly 18 and fresh food door assembly 20 are pivotal about respective vertical axes defined by upper hinges 31 and 32 and lower hinges (not shown).
In general, the structure described above is known in the art and has been provided for a more complete understanding of the figures. The present invention is particularly directed to the construction of freezer door assembly 18 and/or fresh food door assembly 20. However, as each door assembly 18, 20 is preferably, similarly formed, a detailed description will be made with respect to freezer door assembly 18 with an understanding that fresh food door assembly 20 can include corresponding structure, although without structure associated with dispensing assembly 28.
As best shown in FIG. 2, freezer door assembly 18 includes a door pan 43 having a front face portion 45, as well as a top panel portion 48, a bottom panel portion 49 and opposing side panel portions 50 and 51 that collectively define a plurality of corners 54-57. In addition, in order to accommodate ice/water dispensing assembly 28, door pan 43 is provided with an opening 60. In the embodiment shown, each panel portion 48-51 includes a corresponding in-turned flange that establishes an upper, rear face portion 68 (also see FIG. 3), a lower, rear face portion 69 and side, rear face portions 70 and 71 respectively. Face portions 68-71 provide structure for mounting an inner door liner (not shown) to door pan 43.
In accordance with a preferred embodiment of the present invention as illustrated in FIG. 3, side panel portion 50 includes a tab that defines a tab member 74 which is folded so as to be substantially coplanar with top panel portion 48. Likewise, rear face portion 70 is provided with a tab defining a tab element 75 that is also folded so as to be substantially coplanar with top panel portion 48. Tab member 74 and tab element 75, in combination with top panel portion 48, define an aperture or hinge opening 77 at corner 54. In addition to forming hinge opening 77, tab member 74, tab element 75 and top panel portion 48 define a slot 80. As shown, slot 80 extends fore-to-aft across top panel portion 48, spaces top panel portion 48 from both tab member 74 and tab element 75, and leads into hinge opening 77. In accordance with the invention, hinge opening 77 actually defines a hinge corner for door pan 43. Of course, it should be understood that corner 55 would include similar structure so as to also define a longitudinally opposed hinge corner. Hinge 31 is provided with a post or spindle (not shown) that extends into opening 77 to define the axis of rotation for door 18 as discussed further below. In order to provide sufficient structural support to enable door 18 to withstand the rigors of repeated opening and closing, as well as for supporting food items, a corner bracket 90 is affixed at each of corners 54 and 55. Most preferably, a corner bracket 90 is affixed at each corner 54-57 to provide both support and facilitate efficiency in manufacturing. By providing a bracket 90 on each corner 54-57, both right and left hand doors can be advantageously manufactured at the same time so as to more efficiently utilize production resources.
As best shown in FIGS. 3 and 4, corner bracket 90 is provided with a first leg portion 93 and a second leg portion 94 that projects substantially perpendicularly from first leg portion 93. As shown, first leg portion 93 includes an opening 96 that aligns with hinge opening 77. In accordance with one aspect of the invention, when employed in a lower corner position, first leg portion 93 is provided with additional openings 97-99 which register with corresponding openings 100-102 respectively and which are employed for attaching a door closure cam (opening 100) and/or for mounting a lower door stop (openings 101 and 102). Conversely, when employed in an upper corner position, first leg portion 93 may only include a single opening (not shown) for attaching a trim piece. In any event, first leg portion 93 includes a first in-turned flange section 103 and a second in-turned flange section 104. When corner bracket 90 is affixed to, for example corner 54, first, in-turned flange 103 abuts front face portion 45 while second, in-turned flange section 104 abuts or nests against upper, rear face portion 68 to properly locate corner bracket 90 in corner 54. In the preferred embodiment, second leg portion 94 includes a terminal segment 107 that leads to an angled segment 108. Angled segment 108 extends to a third segment 109 that is also substantially parallel to first leg portion 93. Actually, third segment 109 extends towards and interconnects with first in-turned flange 103. In addition, second leg portion 94 is provided with an in-turned flange 112 that is adapted to nest against side, rear face portion 70 when corner bracket 90 is affixed at corner 54.
Reference will now be made to FIGS. 3 and 5 in describing a preferred method of attaching corner bracket 90 to door pan 43. In order to allow the use of pre-painted materials in the construction of door pan 43, corner bracket 90 is joined to door pan 43 without exposing any metal surfaces and using a non-heat generating, non-destructive process. In the most preferred form of the present invention, corner bracket 90 is affixed at corner 54 through a mechanical clinching process. With this technique, a joint is formed having an overlap portion. The joint is actually constituted by the material to be joined. A distinct advantage of this particular process is that the metal is not sheared after pre-finishing as when employing a toggle lock joint, nor is there any significant heat generation such as associated with welding, spot welding and the like.
In accordance with the invention, corner bracket 90 can be affixed at corner 54 using either a standard clinching or a spot clinching process. In order to provide a robust attachment to corner 54, corner bracket 90 is clinched in a plurality of locations spaced about first leg portion 93, as represented at 117 in FIG. 3, as well as along in-turned flange 103 of second leg portion 94 as represented at 118. As best shown in FIG. 5, each clinch 117 is accomplished by pressing a section of rear face portion 68 through in-turned flange 104 of corner bracket 90 to form an overlap section 120. Overlap 120 mechanically joins bracket 90 with door pan 43. A corresponding interconnection occurs for each clinch 118. Due to the absence of shearing forces and heat when forming each clinched joint, a pre-painted material can be used in the production of door pan 43. In this manner, additional production or finishing steps can be eliminated from an overall production process to increase production efficiency without sacrificing quality of the finished product. Moreover, the present invention enables both pre-painted and stainless steel doors to be manufactured on the same assembly line.
Although described with reference to a preferred embodiment of the present invention, it should be readily apparent to one of ordinary skill in the art that various changes and/or modifications can be made to the invention without departing from the spirit thereof. In general, the invention is only intended to be limited to the scope of the following claims.

Claims

1. A refrigerator comprising:

a cabinet including first and second laterally spaced upstanding side walls interconnected by a top wall forming a frontal opening; and

a refrigerator door assembly pivotally mounted relative to the cabinet across the frontal opening, said refrigerator door assembly including:

a door pan including a front face portion, as well as a top panel portion, a bottom panel portion and opposing side panel portions that establish a plurality of corners, at least one of said plurality of corners defining a hinge corner having a hinge opening; and

a plurality of corner brackets, each of said plurality of corner brackets being provided at a respective one of the plurality of corners and including a first leg portion that extends along one of the top panel portion and the bottom panel portion and a second leg portion that extends along a respective one of the opposing side panel portions, wherein said plurality of corner brackets are located in the plurality of corners with each of said plurality of corner brackets being mechanically clinched to the door pan.

2. A refrigerator door assembly comprising:

3. The refrigerator door assembly according to claim 2, wherein at least one of the opposing side panel portions includes a tab.

4. The refrigerator door assembly according to claim 3, wherein the tab defines a tab member that is folded so as to be substantially co-planar with the top panel portion.

5. The refrigerator door assembly according to claim 4, wherein at least one of the opposing side panel portions includes an in-turned flange that forms a side rear face portion, said side rear face portion being substantially parallel to the front face portion.

6. The refrigerator assembly according to claim 5, wherein the side rear face portion includes a tab element, said tab element being folded so as to be substantially co-planar with the top panel portion and positioned adjacent the flange.

7. The refrigerator door assembly according to claim 6, wherein the tab member and tab element are spaced from the top panel portion defining a slot.

8. The refrigerator according to claim 2, wherein the top panel portion and bottom panel portion each include respective in-turned flanges that form upper and lower rear face portions that are substantially co-planar to the front face portion.

9. The refrigerator assembly according to claim 8, wherein the first leg portion of each of the plurality of corner brackets includes a first in-turned section that extends along the front face portion and a second in-turned section that extends along one of the upper and lower rear face portions.

10. The refrigerator door assembly according to claim 9, wherein the second leg portion includes an in-turned section that extends along one of the side rear face portions, each of the plurality of corner brackets being clinched to the door assembly through the at least one of the first and second leg portions.

11. The refrigerator door assembly according to claim 9, wherein the second leg portion includes a first segment substantially parallel to the first leg portion that leads to an angled segment, said angled segment extending to a third segment that is substantially parallel to the first segment and connects with the first in-turned section of the first leg portion.

12. The refrigerator door assembly according to claim 2, wherein each of the plurality of corner brackets is mechanically clinched along one of the first and second leg portions.

13. The refrigerator door assembly according to claim 2, wherein the first leg portion includes an opening adapted to align with the hinge assembly.

14. A method of forming a refrigerator door assembly comprising:

folding a metal sheet to form a door pan including a front face portion, a top panel portion, a bottom panel portion and opposing side panel portions that define a plurality of corners;

forming a flange along at least one of the opposing side panel portions, said flange being substantially co-planar with the top panel portion, said top panel portion and said flange collectively defining a hinge opening at one of the plurality of corners;

clinching a plurality of corner brackets to the door pan at respective ones of said plurality of corners, each of the plurality of corner brackets including a first leg portion that extends along one of the top panel portion and bottom panel portion and a second leg portion that extends along a respective one of the opposing side panel portions.

15. The method of claim 14, further comprising: pre-painting the door pan prior to clinching the plurality of corner brackets.

16. The method of claim 14, wherein each of the plurality of corner brackets is clinched along one of the first and second leg portions.

17. The method of claim 14, further comprising: spacing the flange from the top panel portion to form a slot.

18. The method of claim 14, further comprising: forming an opening in the first leg portion, said opening being adapted to align with the hinge opening.