US3917206A

US3917206A - Refrigerator shelf support assembly

Info

Publication number: US3917206A
Application number: US458256A
Authority: US
Inventors: Richard D Fisher
Original assignee: White Westinghouse Corp
Current assignee: White Westinghouse Corp
Priority date: 1974-04-05
Filing date: 1974-04-05
Publication date: 1975-11-04
Anticipated expiration: 1992-11-04
Also published as: JPS50136761A; ES436318A1; AU7974675A

Abstract

A support assembly for mounting in an aperture of a plastic food liner of a refrigerator having a foamed insulation. The assembly comprises an anchor member, positioned on the back side of the liner for encapsulation in the insulation, having an internally threaded body projecting through the aperture for receipt of a threaded shank of a shelf support member positioned on the front side of the liner. The anchor member also has an enlarged resilient flange terminating in a planar peripheral rim generally radially remote from the aperture and in facing engagement with the back side of the liner to effectively seal the aperture against foam leakage and to be in an opposed pinching relationship with an enlarged flat head portion of the support member with the liner disposed therebetween to effectively reduce the load in the area immediately adjacent the aperture to eliminate critical stress concentrations and resultant failures of the plastic liner thereat.

Description

Nov. 4, 1975 United States Patent [1 1 Fisher REFRIGERATOR SHELF SUPPORT Primary ExaminerJ. Franklin Foss Attorney, Agent, or Firm-Strauch, Nolan, Neale, Nies & Kurz ASSEMBLY [75] Inventor: Richard D. Fisher, Worthington,

Ohio

[ ABSTRACT A support assembly for mounting in an aperture of a a foamed inplastic food liner of a refrigerator having [22] Filed:

[21] Appl. No.1458,256

sulation. The assembly comprises an anchor member,

positioned on the back side of the liner for encapsulation in the insulation, having an internally threaded body projecting throug h the aperture for receipt of 21 positioned on the front side of the liner. The anchor member also has an enlarged resilient flange terminatin [52] US. Cl. 248/239; 85/80; 248/220.5 threaded shank of a shelf support member [51] Int. A47G 29/02 248/239, 220.5; 151/4l.7,

[58] Field of Search g in a planar 151/41, 75; 85/5 R, 80; 403/408 peripheral rim generally radially remote from the aperture and in facing engagement with the back side of the liner to effectively seal the aperture against foam [56] References Cited U IT STATES PATENTS leakage and to be in anopposed pinching relationship with an enlarged flat head portion of the support member with the liner disposed therebetween to effectively reduce the load in the area immediately adjacent the aperture to eliminate critical stress concentrations and resultant failures of the plastic liner thereat.

9 9 HJJD 00 00 mmmnm HSSNO 11.n Wm m m L unan- I M M mum mm NR "I a m 0 m m w a u m RSCFEl 55 4 A 6677 9999 llllN MWHW l I 7078 68550 ,F 92 6 7922 3333 1,385,336 3/1964 France................................ 248/239 8 Claims, 2 Drawing Figures US Patent Nov. 4, 1975 Sheet 1 of2 3,917,206

US. Patent Nov. 4, 1975 Sheet 2 of2 3,917,206

REFRIGERATOR SHELF SUPPORT ASSEMBLY BACKGROUND OF THE INVENTION 1. Field of the Invention The invention relates to an accessory or shelf support for a refrigerator or freezer and more particularly to a support in a refrigerator or freezer having a plastic food liner and foamed-in-place insulation between the liner and the outer shell.

2. Description of the Prior Art The shelves and accessories within a refrigerator or freezer are, in most instances, supported on structure attached to the inner face of the food liner. For the most part, such structure includes apertured vertical columnar members for receiving interlocking tabs or fingers on cantilevered arms attached to the shelves, or channel members for guidingly supporting opposite sides of the shelves. Such support structure, at least in refrigerators having metal food liners, was attached to the liner through various methods such as a plurality of screws spring loaded locking wire or a drive pin expanding type anchor. However, with plastic food liners it has been found that the loads on the liner at the points of attachment with such arrangements were such that the liners became cracked along lines radiating from the apertures for receiving such attaching members. These failures could not be eliminated in a practical manner by merely'inserting plugs or anchors supported by the apertures in the liner and into which support members are then screwed as the liner was still re- 1 quired to support the load in the immediate vicinity of the area weakened by the aperture. Likewise, the locking wire or expanding anchor type attaching members required support in the immediate area already weakened by the aperture. Further, to prevent support structure which had one side particularly adapted for sliding engagement of either shelves or accessories, such as sliding drawers, from turning within the apertures in the liner, it was also common to provide noncircular apertures which further accentuated stress concentrations within the liner.

In assembling a refrigerator or freezer having a plastic food liner, it is evident that if it is to contain an aperture, it would be more convenient to include the aperture in the liner as it was otherwise being fabricated. However, in those refrigerators which had foamed-inplace insulation, the requirement to seal such apertures to prevent leakage of the foam therethrough during the foaming operation negated any advantage of preformed holes and thus, the shelf support structure was required to be subsequently assembled thereto as one of the final steps of the assembly.

SUMMARY OF THE INVENTION The present invention provides a two-piece shelfsupport for a plastic liner of a foamed-in-place refrigerator, and comprises an anchoring member and a support member. The anchoring member includes a tubular body open at one end and having internal threads for receiving the threaded shank of the support member. The anchoring member is inserted into a pre-formed circular aperture in the liner from the rear face and maintained in this position by a slight interference fit.

An enlarged flange extends radially from the tubular body adjacent the open threaded end and defines a planar peripheral rim facing the liner and integral with the body through a dish-shaped continuous web which is concave with respect to the liner and permits resilient displacement of the rim. Upon insertion of the open end into the aperture, the rim contacts the liner with further insertion deforming or displacing the web to instill an inherent biasing force for effectively sealing the engagement between the rim and the liner to prevent leakage of foam during the foaming operation. A support member having a threaded shank is inserted into the bore from the front side of the liner and includes an enlarged head having aplanar face in engagement with the liner. The planar face of the head cooperates with the planar rim of the anchor to tightly engage opposing faces of the liner in an area generally remote from the aperture. The exposed free end of the support defines appropriate structurev for supporting a shelf. The loaded shelf results, in part, in a bending moment which is transmitted to the liner in the area of the re mote engagement of the enlarged head and opposing rim and thereby reduces the forces immediately adjacent the edge of the aperture to an acceptable level to prevent stress failures thereat.

DESCRIPTION or THE DRAWINGS FIG. 1 is a cross-sectional elevational view taken generally along the axis of the assembled support of the present invention; and,

FIG. 2 is an isometric view of the separated components of the support in alignment for proper assembly.

DESCRIPTION OF THE PREFERRED EMBODIMENT The support assembly 10 of the present invention, being particularly adapted for use in a refrigerator having a plastic food liner and foamed-in-place insulation, is shown in FIG. 1 in that environment with a liner l2 spaced from the outer cabinet or shell 14 of the refrigerator with this space being filled by a foamed insulation 16 as is well known in the art. The inner face of the liner l2 defines the food compartment in which the shelves, such as 18, are supported in preselected spaced relationship.

The support assembly 10 comprises two separate members i.e., an anchor member 20 and a support member 22, each preferably comprising a single unitary piece molded from a resilient plastic such as nylon or polypropylene.

The anchor member 20 is, for the most part, disposed on the insulation or rear side of liner 12 and encapsulated in the cured insulation in the final product. As is more clearly seen in FIG. 2, anchor member 20 comprises a generally tubular body 24 having an internally threaded bore 26 providing a single open end 27. The body 24 is preferably circular in at least that portion adjacent the open end 27 so as to permit insertion in a circular aperture 28 in the liner 12 without requiring any special or pre-selected orientation.

The exterior of the open end 27 is tapered rearwardly outwardly as at 30 to form a lead-in shoulder that is also notched as at 31 about its tapering periphery for a purpose to be explained later. Adjacent the shoulder 30 the circular body defines a stepped configuration providing a plurality of shoulders 32 of successively decreasing diameters.

A generally dish-shaped flange 34 extends outwardly from the main body and includes a continuous web portion 36 terminating in a planar rim 38 for facing engagement with the liner 12. A flange 34 is continuous throughout its area so that the area of the rear face of the liner covered by the flange can be effectively sealed from the foam insulation when the rim is in proper facing engagement with the liner.

A plurality of fin members 40 extend radially outwardly along the axis of the body of the anchor such that when the anchor is encapsulated in a cured foam insulation, the fins prevent rotative movement of the anchor and further aid in supporting load induced forces on this stationary end by distributing the forces over a broader area of the cured foam. The extreme distal end of the anchor defines an enlarged circular base 42 that, in like manner to the fins, one encapsulated in cured insulation, maintains the anchor in position against lateral axial movement and also aids in distributing load induced forces in an increased area of the insulation.

The support member 22 is seen to include a threaded shank 44, sized so as to be received within bore 26 of the anchor, having at the free end an enlarged circular head portion 46. The surface 48 of the head portion faces the interior face of the liner l2, and is substantially planar except for the area immediately adjacent the shank 44, with this portion of the head recessed somewhat from the general plane, as at 45, to define a rough or notched concave surface generally complimentary to the notched lead-in tapered surface 30 of the anchor member. The opposite side of the head portion includes an outwardly projecting structure, (in this case cylindrical in form) on which the shelf (or drawer) is supported.

During assembly of the refrigerator, the open end 27 of the anchor member is inserted into the preformed circular aperture 28 of the liner prior to the liner being seated within the outer shell. As previously explained, the diameter of the body at this end varies to provide the outward stepped configuration, however, the initial portion, subsequent to the tapered shoulder of the open end passing through the aperture, has a diameter larger thanthe diameter of the aperture. The resiliency of the material comprising the anchor member 20 plus the tapered lead-in configuration permit relatively easy insertion of the anchor member into the aperture until a diameter of the body member within the aperture is less than the diameter of the aperture while the diameter of the body adjacent the front face of the liner is larger than the diameter of the aperture so that there is a positive engagement to prevent unintentional withdrawal or release of the anchor member. At this point of insertion, the rim 38 is displaced rearwardly a sufficient distance so that the inherent resiliency of the material in the area of the flange which has become stressed due to this displacement biases the rim against the back face of the liner with sufficient force to effectively seal the aperture from the foam insulating material.

In the final stages of assembly of the refrigerator, subsequent to the foam insulation being cured, the support member is inserted into the anchor member as by screwing the shank into the threaded bore. This assembly forces the planar face of the head of the support member against the inner face of liner 12 directly opposite the rim 38 as the outer diameter of the head and the rim are substantially equal. Thus, the load supported by the shelf, which in turn is at least partly supported by each support member, results in a downward force tending to bend the support assembly about its point of securement to the liner. However, this bending force is resisted by the enlarged area of the head contacting the liner on one side and by the rim of the anchor member tightly engagingthe opposing opposite I assembly within the aperture is smaller than the aperture, the assembly is primarily supported by the encapsulation of the anchoring portion within the cured foam. It is acknowledged that a portion of the load could also be transmitted to the edge of the aperture 28, however, for the most part, the amount of the weight supported by the edge of the aperture or bythe liner immediately adjacent the aperture is insufiicient to cause the panel to fail in this area.

Thus, the support assembly of the present invention in addition to permitting complete assembly of the support as a substantially final step by sealing the aperture within the liner prior to foaming, is seen to also be effective to distribute the load induced stresses, trans ferred to the liner, over a generally increased area and generally removed from the weakened area of the panel immediately adjacent the aperture.

It is also apparent that once the foam cures it becomes a structurally stable member that, through the fins and the enlarged base on the body of the anchor, provides sufficient support to the anchor member to relieve the liner from a large portion of its previous load bearing function.

Once the support member has been screwed to a position where it tightly engages the liner the complimentary concave notched portion 45 of the head engages the notched lead-in shoulder 30 of the anchor member to resiliently prevent, under normal conditions, the support member from any further turning and thus establishes a definite orientation that permits the use of a support member which requires definite orientation such as a channel or a flattened support surface, without requiring an aperture capable of determining proper orientation which also, because of such indexing capabilities, would increase stress concentrations as opposed to the stress concentrations resulting from the circular aperture able to be used by the assembly of the present invention.

I claim as my invention:

l. A support assembly for mounting within a circular aperture in the food liner of a refrigerator employing foamed insulation, said assembly comprising:

an anchor member for insertion in said circular aper ture from the back side of said liner said member having a generally tubular body portion open at one end into an internally threaded bore, a circular periphery adjacent said open end and defining abutment means generally complementary to said circular aperture in said liner for interference engagement with the inner side of said liner for retention of said end in said aperture, and flange means extending outwardly from said body from a position axially rearwardly of said open end, said flange being generally concave and terminating in an annular sealing lip for facing engagement with the back side of said liner; and,

a support member comprising an externally threaded shank portion for receipt in said bore and an enlarged head portion defining a substantially planar face on the side thereof towards said shank, said planar face having an area at least coextensive with said sealing lip, and means extending inwardly for supportingly engaging shelf structure;

whereby in assembly, said open end of said anchor member is received in said circular aperture in said liner from the back side prior to the introduction of foam insulation and said shank portion of said support member is inserted into said bore from the front side of said liner with said liner being tightly engaged between said sealing lip of said flange and said planar coextensive portion of said head to distribute a sufficient portion of the load of said supported shelf, transmitted to the liner, to an area of the liner generally remote from said circular aperture to prevent stress failures.

2. Structure according to claim 1 wherein the diameter of the periphery of said abutment means varies from greater than said aperture to less than said aperture opposite the directions of insertion and wherein the diameter of the portion of the anchor member received within said aperture is less than the diameter of said aperture.

3. Structure according to claim 2 wherein said sealing lip resiliently engages the rear side of said liner in an effective sealing engagement when said abutment means engage said opposite side of said liner and said diameter of said complemenatry surface within said aperture is less than the diameter of said aperture.

4. Structure according to claim 3 wherein said tubular body includes means extending outwardly therefrom to prevent rotation of said body in said foamed insulation subsequent to said foam hardening, said last named means further providing means for distributing the support of the load by said hardened foam to a generally increased area.

5. Means for supporting shelves or the like within a refrigerator having an outer cabinet generally enclosing a plastic liner forming the interior walls, the space between said cabinet and liner having foamed insulation and wherein said supporting means comprises:

an anchor member for insertion in a circular aperture from the backside of said liner said member having a generally tubular body portion with at least one end open defining an internally threaded bore, a circular external periphery adjacent said open end and defining abutment means generally complementary to said circular aperture in said liner for interference engagement of said end with the inner side of said liner, and a generally enlarged flange extending radially from said body from a point axially rearwardly of said open end, said flange termi- 6 mating in an annular sealing portion facing the backside of said liner; and,

a support member having an externally threaded shank portion for complementary threaded receipt in said bore and an enlarged head portion defining a substantially planar face toward said liner with at least a portion thereof generally coextensive with said sealing portion and means extending on the opposite side of said head portion for supportingly engaging shelf structure or the like;

so that in assembly, said open end of said anchor member is received within said circular aperture in said liner from the backside and said support member is inserted into said bore from the front side, with said liner being tightly engaged between said sealing portion of said flange and said coextensive portion of said head to distribute a sufficient portion of the load of the shelf transmitted to the liner to an area of the liner generally remote from said circular aperture to prevent stress failures thereat.

6. Structure according to claim 5 wherein the diameter of the periphery of the abutment means varies from greater than said aperture to less than said aperture opposite the direction of insertion and wherein the diameter of the portion of said anchor member received within said aperture is less than the diameter of said aperture.

7. Structure according to claim 6 wherein said sealing lip resiliently engages the rear side of said liner in an effective sealing engagement when said abutment means engage said opposite side of said liner and said diameter of said complementary surface within said aperture is less than the diameter of said aperture to prevent said foam insulation from escaping through said aperture.

8. Structure according to claim 7 wherein said tubular body includes means extending outwardly therefrom to prevent rotation of said body in said foamed insulation subsequent to said foam hardening, said last named means further providing means for distributing the support of the load by said hardened foam to a generally increased area; and,

the end of said tubular body adjacent said opening defines a separated surface for interfering resiliently engaging a complimentary surface on said head portion to prevent relative rotation of said support member to said anchor member when assembled together to engage said liner.

UNITED STATES PATENT AND TRADEMARK OFFICE CERTIFICATE OF CORRECTION PATENT NO. 3,917,206

DATED November 4, 1975 |NVENTOR(S) 1 Richard D. Fisher It is certified that error appears in the above-identified paterit and that said Letters Patent are hereby corrected as shown below:

Column 1, line 64 insert -areaafter "rim" *Claim 8, line 9, (Column 6, line 44) "separated" should be --serrated.

Signed and Sealed this mm fifteenth Day Of June 1976 Arrest:

RU'I'H QMA SON C. MARSHALL DANN Aflnmlg Officer Commissioner nj'larems and Trademarks

Claims

1. A support assembly for mounting within a circular aperture in the food liner of a refrigerator employing foamed insulation, said assembly comprising: an anchor member for insertion in said circular aperture from the back side of said liner said member having a generally tubular body portion open at one end into an internally threaded bore, a circular periphery adjacent said open end and defining abutment means generally complementary to said circular aperture in said liner for interference engagement with the inner side of said liner for retention of said end in said aperture, and flange means extending outwardly from said body from a position axially rearwardly of said open end, said flange being generally concave and terminating in an annular sealing lip for facing engagement with the back side of said liner; and, a support member comprising an externally threaded shank portion for receipt in said bore and an enlarged head portion defining a substantially planar face on the side thereof towards said shank, said planar face having an area at least coextensive with said sealing lip, and means extending inwardly for supportingly engaging shelf structure; whereby in assembly, said open end of said anchor member is received in said circular aperture in said liner from the back side prior to the introduction of foam insulation and said shank portion of said support member is inserted into said bore from the front side of said liner with said liner being tightly engaged between said sealing lip of said flange and said planar coextensive portion of said head to distribute a sufficient portion of the load of said supported shelf, transmitted to the liner, to an area of the liner generally remote from said circular aperture to prevent stress failures.

5. Means for supporting shelves or the like within a refrigerator having an outer cabinet generally enclosing a plastic liner forming the interior walls, the space between said cabinet and liner having foamed insulation and wherein said supporting means comprises: an anchor member for insertion in a circular aperture from the backside of said liner said member having a generally tubular body portion with at least one end open defining an internally threaded bore, a circular external periphery adjacent said open end and defining abutment means generally complementary to said circular aperture in said liner for interference engagement of said end with the inner side of said liner, and a generally enlarged flange extending radially from said body from a point axially rearwardly of said open end, said flange terminating in an annular sealing portion facing the backside of said liner; and, a support member having an externally threaded shank portion for complementary threaded receipt in said bore and an enlarged head portion defining a substantially planar face toward said liner with at least a portion thereof generally coextensive with said sealing portion and means extending on the opposite side of said head portion for supportingly engaging shelf structure or the like; so that in assembly, said open end of said anchor member is received within said circular aperture in said liner from the backside and said support member is inserted into said bore from the front side, with said liner being tightly engaged between said sealing portion of said flange and said coextensive portion of said head to distribute a sufficient portion of the load of the shelf transmitted to the liner to an area of the liner generally remote from said circular aperture to prevent stress failures thereat.

8. Structure according to claim 7 wherein said tubular body includes means extending outwardly therefrom to prevent rotation of said body in said foamed insulation subsequent to said foam hardening, said last named means further providing means for distributing the support of the load by said hardened foam to a generally increased area; and, the end of said tubular body adjacent said opening defines a separated surface for interfering resiliently engaging a complimentary surface on said head portion to prevent relative rotation of said support member to said anchor member when assembled together to engage said liner.