US2816331A - Freezer cabinet door construction - Google Patents

Description

.Dec. 17, 1957 R. E. MOORE 2,816,331

FREEZER CABINET DOOR CONSTRUCTION Filed Oct. 9, 1953 3 Sheets-Sheet 1 Poberz E. Moore H I Z 2 75 Dec. 17, 1957 R. E. MOORE FREEZER CABINET DOOR CONSTRUCTION 3 Shgets-Sheet 2 Filed Oct. 9, 1953 E. Moore i7. .Z/"E T1 TET Foberz 3 Sheets-Sheet 3 R. E. MOORE FREEZER CABINET DOOR CONSTRUCTION I Faber! E. Moore WW a H Z Z L 75 United States Patent FREEZER CABINET noon CONSTRUCTION Robert E. Moore, Cedar Rapids, Iowa, assignor to Aniana Refrigeration Inc., a corporation of Town Application October 9, 1953, Serial No. 385,143

2 Claims. (Cl. 20-35) The present invention relates to a two piece door construction, and more particularly, is concerned with the provision of a novel insulated door for use with freezer cabinets, refrigerators, or the like.

With the advent of food freezer units operating at temperatures far lower than the common household refrigerator, many problems of construction have arisen. For example, it has been found desirable to utilize a greater amount of insulating material throughout the freezer cabinet in order to prevent sweating on the outside surface of the freezer units. The use of additional insulating material has made desirable a thicker door unit. In utilizing doors constructed in accordance with the principles known in the prior art, this requirement of additional thickness in food freezer doors has limited to a.

certain extent the use of the door as a food holding unit. Through the present invention, however, a novel door construction is provided which permits the use of a large amount of insulation while at the same time providing food storage space within the door far in excess of anything known in the prior art. Through the use of the present invention, this is accomplished in an extremely inexpensive and yet extremely satisfactory manner.

In accordance with the principles of the present invention an outer door shell, preferably of deep drawn sheet steel, is provided in combination with a deep drawn inner steel shell. These shells are maintained in a separated position through the use of a novel corner bracing struc-- ture which permits equalization and adjustment of the door structure during installation thereof on a food freezer cabinet while simultaneously permanently separating the outer and inner shells to provide an insulating space therebetween.

The outer and inner shells are connected to each other at their inner edges by means of a novel breaker strip which is constructed of thermally resistant material and which is provided with novel condensate control apertures for disposing of condensate formed in the inner liner shell. The invention also provides bracing structure between the inner and outer shells which is constructed of an insulating material thereby completely isolating, thermally, the outer and inner door shells.

Through the use of the novel outer and inner deep' drawn door shells combination with the novel method of corner bracing these two members relative to each other in an insulated manner, and through the provision of a novel insulating breaker strip, I have been able to provide a freezer door having extremely large food storing capacity. At the same time room is provided for a large amount of insulating material between the shells and the door is given sufficient rigidity to prevent distortion due -to its own rather large proportions.

It is therefore an object of the present invention to provide a food storage door having an outer and an inner shell completely insulated relative to one another.

Another object of the present invention is to provide a novel freezer door having outer and inner shells structurally connected at the corners thereof to provide an adjustable cross bracing means for preventing distortion of either shell.

A further object of the present invention is to provide a novel freezer door having an inner shell forming a food storage space therein, constructed of deep drawn sheet metal and providing a bracing effect for the outer door.

Yet another object of the present invention is to provide a novel cross-braced freezer door having separate inner and outer shells with condensate removal means associated therewith.

A feature of the present invention is the provision of a novel breaker strip for insulating the inner and outer shells of the freezer door while at the same time providing a cover for the structural elements thereof which is pleasing to the eye.

Another feature of the present invention is the provision of a novel cross bracing structure constructed of insulating plastic in combination with a vertically and horizontally stiffened inner door pan.

Yet a further feature of the present invention is the construction of a food storage space in a food freezer door which is constructed of steel while at the same time thoroughly insulating the storage space from the outer freezer door housing.

Still other and further objects and features will at once become apparent to those skilled in the art from a consideration of the attached drawings in which a preferred embodiment of the present invention is shown by way of illustration only.

On the drawings:

Figure 1 is a side elevational view, partly broken away to show structural details, of the inner portion of a vertical door constructed according to the principles of the present invention;

Figure 2 is a cross sectional view taken along the line II-II of Figure l and showing the structural interrelationship found in the door of the present invention;

Figure 3 is a cross sectional view taken along the line IIIIII of Figure 1 and illustrating the reenforced rib structure utilized in the food storage shell of the present invention;

Figure 4 is a cross sectional view taken along the line IVIV of Figure l and illustrating the novel condensate control means utilized in the present invention; and

Figure 5 is a cross sectional view taken along the line V--V of Figure 2, further illustrating the novel bracing structure herein disclosed.

As shown on the drawings:

A consideration of Figures 1 and 2 discloses that the door of the present invention comprises an outer door shell 10 and an inner door shell 11. The outer door shell 10 is constructed substantially in accordance with principles known in the prior art although it is substantially deeper than those heretofore known. Preferably, the shell 10 is constructed of deep drawn sheet steel and may be provided with ornamental depressions, trim or peripheral contours such as at 12 for providing eye appeal and rigidity.

The inner liner 11 is constructed according to principles not heretofore known in the prior art and comprises a deep drawn liner having a substantially rectangular configuration with walls 13 and the bottom 14.

In the prior art the use of a deep drawn sheet metal inner door shell was considered impractical for freezers due to the fact that it was considered thermally undesirable to utilize heat conducting sheet metal for the entire inner door structure. Further it was very difiicult to provide a deep inexpensive plastic inner door liner assembly. This was true since it was believed necessary to attach the inner liner 11 directly to the outer shell 10 Patented Dec. 17, 1957v complete isolation of the inner shell from the outer 10,. except through heat insulating materials, wliiclil'atter materials assume structural functions in supporting the door structure.

The inner door, shell 11; is secured to the outer. shell.

through the use of cornerbrace gussets 15" at the bottom of the door 10 and 16 at the top thereof. The gussets 15. and 16 are rigidly secured to the inwardly turned flanges 1.7 of the outer. door shell 10, by any suitable means such as for example by spot welding. Secured to the gussets 15 and i6 aretheangularly mount ed braces 18 which are constructed of a high strength insulating material such: as; for example, fabric. reenforced' plastic having substantially" rigid characteristics but' it' is of course to be understoodthat numerous heat insulating materials may be utilized as the structuralelements 18 without departing from the concepts'of'the'present invention;

The braces 18 are provided with a pair of expansion type nuts-19*and ztl'at one end thereof; and the'third fastener 21 at the opposite" end thereof. Long through bolts 2 2and23 passing through thenuts 1 9 and and through a U-shaped' spacerelementrigidly secure thebraces lifto-the gussets- 1 5 and T6; in a-plane'substa-ntially parallel thereto;- The inner-shell 1-1 i's-n'gidly secured to the braces 18 by means of th'eb'ol't 24, thereby providing, as may be seen from Figure l''-, a securely braced structure which suspends the inner door: shell 11' at eachof its four cornersto the four corners of the.-

outershell 10:

In the assembly of the inner and outershells the-- four gussets, spacer, and brace assemblies are loosely assembled with. the bolts 22', 23 and tightened firmly but; not tightly'into-position. The outer door' shell may then be placedlin a fixture which accurately levels the entire door, thereby maintaining it in positiomagainst any tendency to becomeout of square asia result: of. warping etc. andltheibolts and their; nuts'26 then securely tightened down. Whenthe shell'is thenrernoved from the fixture, the brace: and spacer structure will: maintain it inits square condition: thusv insuring a perfect. fit whenz-the entire, door assembly is later mounted on. the freezer; cabinet.

It-is to be; noted that-only at nominal amount of: slack isgnecessaryirr-the :spacerrandassembly to :permit suflicient movement to 1 counteract any warpingscwhich. accompany.-

the; manufacturing. Process, and: ,for: this purposes it is therefore considered satisfactory merely to make the boltn: holes in the liner bottom 14- slightly, larger thanttheibolts 22, 23 and 24. However, whilethexadjustment'need 'not be large,- it is;-extremely important sinee.,a..very slight amount ofmisalignment. isvvery noticeable in a. large; door ofthe-type utilizedwith-freezersof thepresent in-.

vention.

While the assembly above-mentioned may; of .coursebe carried out in a fixtureor jig as above described, it.

withheat insulating material, such as for examplefiber This batting, shown at: Bdprevents the, thermal:transfer-betweentthe inner shell. 11- audthe. outen glass batting,

shell10..

Inorder to cover the insulatiomandin order to. provide a. decorative: outer appearance; a breaker strip 31 4. is provided around the periphery of the door. This strip, which is preferably constructed of a resilient, high impact strength plastic having thermal insulating characteristics, such as for example high impact strength polystyrene, is secured by any conventional means such as rivets or bolts 32 to the flange 17 of the outer shell 10.

The inner edge 31a of the breaker 31 is maintained in secure engagement with the outer lip 13a of the side wall i theinner liner 11 by its own inherent resiliency which is also aided by the. resiliency of the outer door gasket 33' which is positioned between the breaker 31 and the flanges 17 as shown in Figures 1, 3 and 4. A further depression- 132') is. provided for cooperation with the lip 31!) to provide a substantially sealed relationship therebetween.

Slight differences in the expansion characteristics of the plastic 31 and the sheet steel 10 and 11 encountered duringcooling will. of course be taken. up by means of therelativelyfree relationship between the breaker strip 31 and the portions 13a and 13b of the inner shell 11'. In view of this relatively free relationship, it is clear that the breaker strip 31 forms substantially no structural supporting structure relative to the inner linerw 11'. Instead, substantially alliof the support for the inner liner 11 is provided'through the. spacer and strut structure 25, 18;.

Since,.un'like prior art structures, the inner door structure of the. present invention. comprises a deep drawn steel plate in combination with the plastic breaker strip, there will of course be a joint at the abutting edges of these two members. Since no sealing compound is utilize'dbctween these'two elements it is necessary to provide means for'carrying 01? any; condensate which may develop within the inner shellfll-l and move by force of gravityto the lip 132i .at'the bottonrof the door.

In: the" present invention; condensate is removed by permitting itto pass through the apertures 34 in the bottom'portio'n' of the breaker'strip 31. These slots are molded into the breaker strip" bearing the initial molding operation thereof and are clearly shown in the cross sectional view found'in Figure 4; In'that' showing, the breaker strip- 31, which is secured totheflange 17 by means of the fasteners 32'overlies the portions 13a and 13b of the innershell 11; Condensate-forming on the uppersurface of the wall 13 'fl0Ws downwardly'between the-portions lSa, IS'band 'the lip 31a andthroughthe surface tension of the condensate associated with the plastic 31-, the condensate drips through the openings- 34. A-

backing'wall' 35- is providedto prevent the possibility of condensate being dripped downin-back ofi the-member 31 upon slamming the freezer door or-any other similar:

activity; The'segments 36 betweenthe slots 3:4 aretriangular-1y shaped; saving a top sharp edge 37-; therebycausingany-condensate which should drop-upon a divider 36 m flow downwardly through a slot 34- on one side or the .otherthereof.

The large, molded, plasticbreaker' strip 31 is also isnabruptly closed or; opened; Further apertures 41: and: 42 are provided. for: conventional i refrigerator. lightswitch and door latch. mechanisms;.

Upon assembly of'the breakcr-sstrip: 31- to the: innerandouter shells 1 1v and 1.0: respectively, and subsequent to the insulationzof. the-. bracing strut 18: and itsassociated structure, the door may be; secured tov a-freezer. cabinet by means of conventionalv hinges 432whichare= securedto the-sideflangcsfl by conventional fastenerssuch as .bolts or.- -.welding: It is to be understood,,of; course,.that the freezer cabinetper-se. formsznorpartofi theipresent in ventionand hence: no; showing thereofis: made in .app1icautsrdrawings;

In order to render the entire door structure more rigid, and, further, in order to provide air circulation about the food stored in the inner shelf 11, ribs 44 are provided in the inner shell 11. A substantially peripheral side groove 45 also extends around'the inner edge of the inner shell 11 to provide rigidity in both vertical and horizontal directions. This rigidification of the inner shell 11, when combined with the bracing eifect oifered through the members 18, provides an inner and outer door assembly which is extremely well cross braced. It has been found that freezer doors constructed according to the principles of the present invention have substantially no tendency to become out of square or otherwise warped during service.

The spacer 25 is constructed in a simple, yet extremely rugged fashion from sheet stock. This material is bent as at 46 to form a U and is ridged as at 47 to provide substantial rigidity. Projections 48 are provided in the extremities of the U and the bight portion of the U is provided with a pair of apertures 49 which cooperate with the bolts 22 and 23. Apertures 50 in the gusset plates 15 and 16 cooperate with the projections 48 to maintain the members 25 in substantially squared relationship relative to the gusset plates and, thus to flanges 17 of the outer frame 10. When the bolts 22 and 23 are securely fastened down, the U-shaped spacer 25 is thus provided with a four point contact at the corners 51 and at the bight portion 52, the latter being stressed at the apertures 49.

it has been found that this four point structural relationship in combination with the braces 18 provides a cross brace structure which has substantially no tendency to deform under the weight on the inner door shell 11, even though substantial loads are placed thereon by the storage of food therein. Since no shelves have been shown within the inner shell 11, for the storage of food, it is to be understood that such shelving forms no part of the present invention and therefore, any conventional type of packaging shelves may be utilized for this purpose. However, it is to be noted that the structure of the present invention permits the use of a very deep inner liner and the use of deep shelves for such items as frozen food packages is desirable.

It will thus be seen, from a consideration of the above description, that I have provided a novel refrigerator or freezer door structure which permits the use of a deep drawn, inner shell liner in combination with a sheet metal outer shell while at the same time providing a complete thermal isolation between these two members. Further, the above structure has provided a freezer door which is substantially more rigid than those known in the prior art through the novel cross bracing structure herein above disclosed and through the novel rigidification found in the inner liner shell itself.

It is to be understood, of course, that modifications and variations may be made to the above disclosed structure without departing from the novel concepts of the present invention.

I claim as my invention:

1. A refrigerator door or the like comprising an outer shell, a deep drawn inner shell secured igidly thereto at the corners thereof by thermally non-conductive means said inner shell nesting at least partially within said outer shell, and thermally non-conductive breaker strip means secured to one of said shells and maintained in resilient contact with the other of said shells whereby a completely, thermally isolated door structure is provided, said breaker strip means having apertures therein in the portion thereof associated with the bottom of said door whereby condensation formed in said inner shell may escape therefrom, said apertures having drip deflecting walls at the back thereof and underlying the edge of said inner shell to prevent passage of accumulated condensation into the space between said shells.

2. An adjustable door structure comprising a deep drawn outer shell member having inwardly turned securing flanges at the periphery thereof, an inner shell having apertures at the four corners thereof, and gusset means secured to said inwardly turned flanges at each of the corners of said outer shell for the attachment of thermally non-conductive bracing means, said bracing means comprising a strap rigidly secured in spaced relation to said gusset and secured at its opposite end to the respective aperture in said inner shell, and spacer means between said strap and said gusset for maintaining said strap in fixed relation to said peripheral flange, said spacer comprising a U-shaped sheet metal element having the ends of the legs thereof positioned in apertures in said gusset and having the bight thereof maintained against said strap, and having securing means passing through said strap, said bight and said gusset to maintain said strap and said spacer securely aflixed to said gusset in fixed angular relationship thereto.

References Cited in the file of this patent UNITED STATES PATENTS 2,335,185 Hull Nov. 23, 1943 2,553,832 Richard May 22, 1951 2,665,456 Morton Jan. 12, 1954 2,718,446 Hinkel Sept. 20, 1955 FOREIGN PATENTS 107,231 Australia May 4, 1939

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