US2852328A

US2852328A - Refrigerator door inner liner

Info

Publication number: US2852328A
Application number: US590025A
Authority: US
Inventors: William R Jewell; John W Pulaski
Original assignee: General Electric Co
Current assignee: General Electric Co
Priority date: 1956-06-07
Filing date: 1956-06-07
Publication date: 1958-09-16
Anticipated expiration: 1975-09-16

Description

' Sept. 16, 1958 w. R. JEWELL ET AL 2,852,328

REFRIGERATOR DOOR INNER LINER Filed June '7, 1956 F! G. I

FIG. 3

26 INVENTORS WILLIAM R. JEWELL & OHN W. PULAQKI BY WW THEI R ATTORNEY Unit rates Pate REFRIGERATOR DOOR INNER LINER William R. Jewell, Lyndon, and John W. Pulaski, Louisville, Ky., assiguors to General Electric Company, a corporation of New York Application June 7, 1956, Serial No. 590,025

1 (Jlaim. (Cl. 312-214) The present invention relates to refrigerator inner door liners and more particularly to an inner door liner adapted for supporting adjustable shelves, and to a method of making such a door.

Many refrigerator doors currently used comprise an inner door or liner including means for supporting a plurality of shelves for the storage of food stuffs. For convenience these storage shelves should be adjustable, and for that purpose the inner door is normally provided with a plurality of shelf supporting means whereby the shelves can be arranged on the inner door in any of a plurality of positions. A vacuum formed inner door of this type is disclosed and claimed in the copending application of Victor J. Kurowski, Serial No. 439,561 filed June 28, 1954, now Patent No. 2,784,044, and assigned to the same assignee as the present invention. The present invention is an improvement over the invention of the Kurowski application, which was made by Kurowski prior to the present invention. Therefore, we do not claim as our invention anything shown or described in the Kurows'ki application, which is to be regarded as prior art with respect to the present application.

In the inner door structure covered by the Kurowski application, the vacuum-formed, refrigerator inner door liner includes a recess, a row of vertically spaced bosses formed integrally on each side wall of the recess adjacent the front of the side wall and extending into the recess, and a plurality of rows of vertically spaced depressions formed within the recess and rearwardly of the bosses whereby a removable shelf or shelves can be supported by the cooperating bosses and depressions. in the vacuum forming of the door described and claimed in the Kurowski application, a forming mold is employed having movable means for forming each of the bosses. movement of these means being provided in order to remove the vacuum formed door from the mold.

It is an object of this invention to provide a vacuumformed, refrigerator inner door liner having shelf-supporting projections integrally formed upon the side walls of the liner and including inwardly extending flange portions for concealing these projections thereby providing a continuity of appearance, as distinguished from the appearance of the unconcealed and separated bosses formed by the Kurowski invention.

It is another object of this invention to provide a vacuum-formed, refrigerator inner liner including a shelf receiving recess with an integrally formed ledge extending along the edges of the recess side walls for providing concealment for shelf supporting projections, both the ledge and projections being formed around a reinforcing structure.

It is another object of this invention to provide an improved method of vacuum forming and reinforcing a plastic refrigerator inner liner having a recess and over- 2,852,328 Patented Sept. 16, 1958 Further objects and advantages of the invention will become apparent as the following description proceeds, and the features of novelty which characterize the invention will be pointed out with particularity in the claims annexed to and forming a part of this specification.

In carrying out the objects of this invention there is provided a refrigerator inner door liner having upstanding side walls which define a recess including shelf supporting means positioned upon the side walls adjacent the front thereof. A continuous ledge extending inwardly from the side walls and overhanging the recess provides concealment for the shelf supporting means. Means for forming and reinforcing the overhanging ledges is provided by metal reinforcing members which 7 are removably positioned on the mold used to vacuum form the door liner, the inserts being molded into the liner simultaneously with the forming of the liner and being removed therewith at the end of the molding operation.

For a better understanding of this invention reference may be had to the following description taken in conjunction with the accompanying drawing in which:

Fig. l is a side elevation view partly in section of a refrigerator door showing the improved shelf mounting arrangement of this invention;

Fig. 2 is a perspective view of the shelf mounting arrangement of Fig. l with a portion of the plastic liner broken away to show the relationship between the liner and the reinforcing insert;

Fig. 3 is a partial cross sectional view of a vacuum mold showing the formation of a side wall of the liner with the overhanging flange and projections extending into the liner recess in accordance with this invention.

Referring now to Fig. 1, there is shown a refrigerator door of the type having an outer shell 1 and an inner liner 2 including a recess 3. The outer shell l is preferably formed of sheet metal, but the inner liner 2 is preferably formed of a plastic heat insulating material, as for example polystyrene, cellulose acetate, or a polystyrene-rubber compound, etc. The space between the inner and outer walls is filled with a suitable thermal insulating material 4. The recess 3 in the liner provides an additional storage space in the refrigerator in which shelves may be mounted for supporting various foodstuffs. The recess 3 includes a rear wall 5 and right and left side walls 6 and 7, the side walls extending substantially at right angles to the rear wall 5. Although such is not necessary to the invention, in the preferred embodiment illustrated, the side walls 6 and 7 extend outwardly beyond the principal face 8 of the liner 2 upon which a gasket 9 is mounted, as shown in Fig. 1.

By this outward extension of the side walls 6 and 7, a

side wall 6 a vertical row of steps or shoulders 12 upon which the back or rear edge 13 of the shelf 11 rests. This edge of the shelf, in the present embodiment of the invention, is rolled under and supports the shelf 11 in a horizontal position. It is to be understood that a similar row of steps or shoulders 12 is formed upon.

the rear portion of the left side wall 7 and the shelf i:

supported at its ends thereof by the corresponding shoulder on each side wall.

that some variation may be made in the position of the rows of shoulders 12; for example instead of being,

It will also be understood 1) formed on the side wall they could obviously be formed on the'principal flat surface of the rear wall 5.

By the present invention, in order to provide support for the front end of the shelf 11, there is formed on the side walls 6 and 7, adjacent the front thereof, an over-.

hanging ledge 14 having a series of alternately spaced projections 15 and depressions 16. More specifically, the projections 15 just back toward .the rear wall 5 of the recess 3 and are concealed by the ledge 14. The depressions 16 face the vertical row of shoulders 12. The adjustable shelf 11 is provided on its forward edge with an upstanding front guard 17 having a configuration, at least upon its end portions thereof, designed to fit snugly into pairs of adjacent depressions 16 formed in the overhanging ledge 14. That is, as shown in Fig. l, the front guard 17 is formed such that a reversely bent portion 18 at the bottom of the guard fits snugly into one depression 16 in the overhanging ledge 14 and a second formed portion 19 in the upper portion of the guard fits into the depression 16 next above, such that a projection 15 is surrounded upon three sides by the guard 17. Thus the shelf is vertically supported at its rearward end by the shoulders 12 on each side wall and at its forward end by pairs of projections 15 on each side wall; i. e. one projection 15 on each side wall upon which the shelf rests and another projection 15 on each side wall which is engaged by the upper edge of the frontguard 17. The manner in which the

portions

18 and 19 of the front guard engage the depressions 16 and projections 15 on the overhanging ledge 14 of the liner is clearly shown in Fig. 2.

In order to mount the shelf within the recess 3, it is first inserted between the side walls within the recess and substantially positioned in the dotted line position illustrated in Fig. 1 with the rear edge 13 extending downwardly into the recess. The rear edge 13 is then positioned upon any two horizontally aligned shoulders 12. The shelf is rotated downwardly using the rearward edge 13 as a pivot until the shelf is horizontal and the formed

portions

18 and 19 on the front guard fit snugly around a projection 15 and extend into two adjacent depressions 16. During rotation of the shelf the front guard 17 is sprung slightly inwardly thereby providing clearance between the lower corner 21 of the projection 15 and the reversely bent formed portion 18 on the bottom part of the front guard 17. The shelf is thus firmly supported within the door liner and may be removed therefrom simply by reversing the procedure outlined above. The shelf may be supported at various positions along the cavity, and normally there are several shelves so mounted within the cavity depending upon the foodstuffs to be stored.

In order to form the overhanging ledges 14 of the liner, such as illustrated in the above embodiment, and in order to provide a reinforcement therefor there is provided a member or insert 22. The reinforcing member 22, in addition to' its functioning as a reinforcement, provides an inexpensive means for vacuum forming the concealing ledges 14 which overhang into the recess from the sides of the liner. This eliminates the requirement for expensive molds having retractable elements around which to form the bosses or overhanging ledges. In the illustrated embodiment of the invention, as may best be seen in Figs. 2 and 3, the reinforcing insert 22 is formed from a longitudinal piece of flat sheet metal and is provided with one side bent substantially normal to the main face of the insert to form a holdingflange 23 for temporarily anchoring the insert on the mold during the liner molding operation. The opposite side or ledge forming flange of the reinforcing insert is stamped or roll formed and bent to provide a series of alternate projections 24 and recesses 24a. The projections 24 therefore com prise a series of reversely bentflanges which are hereafter designated projection forming flanges according to the function they perform during the molding process, to be later described.

The reinforcing member 22 lies along the top edge of the side wall, flush with the inner surface of the plastic liner and extends into the overhanging ledge 14 of the side wall, as clearly shown in Fig. 2. The plastic material of the overhanging ledge 14 is drawn tightly around the projection forming flanges 24 thereby forming a series of alternate projections 15' and depressions 16 extending toward or facing the rear wall 5 of the recess. Thus the reinforcing insert 22 braces the overhanging ledge 14 against outward thrust during the positioning of a shelf and provides a reinforcing structure within the projections 15 for vertical support of the load upon the storage shelves.

The use of the reinforcing insert 22, in vacuum forming the overhanging ledges 14- of the side walls, simplifies the removal of the finished liner from the mold during the vacuum forming operation as can best be seen by, reference to Fig. 3 showing a cross sectional view of a portion of a vacuum mold 26 adapted for vacuum forming of a plastic inner door liner. Only that portion of the mold necessary to form a side wall and a part of the recess is shown in Fig. 3 but it is to be understood that the mold contains all the necessary portions or elements to form one complete inner liner during the vacuum forming process. For carrying out the present invention, the mold used comprises an upstanding side wall 27 having a pair of slanting

sides

28 and 29, and an outer edge surface 31. Adjacent the slanting side 29 at the junction of the side 29 and the cavity face 32 of the mold are a series of steps or shoulder forming elements 33 one of which can be seen in cross section in the diagram. Approximately in the center of the outer edge surface 31, there is provided a longitudinal groove 34 which extends substantially the length of the outer edge surface 31. From the longitudinal groove 34 inwardly towards the recess 3 or the slanting side 29, the outer edge surface-31 is preferably stepped down a distance approximately equal to the thickness of the metal reinforcing member 22.

In forming a plastic inner door liner, a pair of rein= forcing inserts 22 are positioned on the outer edge surfaces 31 of the upstanding side walls 27 of the mold.

" As can-be seen in Fig. 3 the holding flange 23 is inserted into the groove 34 in the outer edge surface such that the ledge and projection forming flange of the insert extends into and overhangs the cavity of the mold. A sheet of heated thermoplastic material is placed over the mold and then the air lying between the sheet of thermoplastic material and the mold is exhausted so that the atmospheric pressure forces the sheet of thermoplastic down into the mold to assume the contours thereof. In

order to draw a vacuum beneath the sheet once it is placed over the mold, a plurality of passageways are provided in the mold extending to the surface thereof, and connected at their lower end to a large vacuum chamber 35 defined in the base of the mold. Vacuum chamber 35 is itself further connected by a conduit 36 to a suitable vacuumpump. A series of exhaust passages 37 located in the upstanding side wall 27 lead to the surface of slanting side 29 at a point just below the projection forming flanges 24. Exhaust passages 37 serve to fold the plastic sheet closely around the flanges 24 and also to draw the plastic sheet into the recesses formed between the projection forrning flanges 24. It is to be understood'that there are a number of these passages leading to the surfaces of the mold at a plurality of points spaced longitudinally along the slanting side 29 and adjacent the projection forming flange 24.

In the present invention, by having the groove 34- and the holding flange 23 normal to the outer edge surface 31 removing the completed liner will present no problem since the holding. flange 23'slides out of the groove 34 as the liner is removedfrom the mold, with the rein'-' forcing inserts forming an integral part of the side wall of the liner. This eliminates the necessity of providing an expensive and elaborate mold having elements for forming the overhanging edge that must be retracted into the side walls of the mold liner can be removed.

Thus, it may be seen that by the present invention there is also provided a vacuum molding method which is eifective to form a recessed plastic liner having a sharply defined ledge overhanging the recess from the side walls and having shelf supporting projections. By the use of reinforcing inserts supported by the mold and separable therefrom to form the overhanging ledge of the inner door liner there is provided a convenient method of performing the vacuum molding operation. Moreover by using the inserts in the side walls as reinforcing means for the overhanging portions there is provided 21 particularly sturdy inner door linear structure.

While in accordance with thepatent statutes there has been described what is at present considered to be the preferred embodiment of this invention, it will be obvious to those skilled in the art that various changes and modificiations may be made therein without departing from the invention and therefore it is the aim of the appended claim to cover all such changes and modifications as fall within the true spirit and scope of the invention.

What we claim as new and desire to secure by Letters Patent of the United States is:

so that the completed A refrigerator inner door liner having upstanding side walls defining a recess including a plurality of shoulders formed on the rear face thereof for supporting the rear edge of a shelf at a plurality of positions within the recess, a shelf front edge supporting means comprising a continuous ledge extending from each of said side Walls adjacent the front thereof and overhanging said recess, a row of alternate projections and depressions formed integrally upon said overhanging ledge on each side wall of said recess, said projections being directed inwardly towards said shoulders on said rear face of said recess, said depressions of said row on side wall being horizontally aligned with said depressions of said row on said opposite side wall, and longitudinal metal reinforcing members vertically positioned Within said side walls, each of said reinforcing members having a flanged extension forming an integral part of said overhanging ledge and also forming an integral part of said projections.

References Cited in the file of this patent UNITED STATES PATENTS 2,746,828 Amore May 22, 1956 2,784,044 Kurowski Mar. 5, 1957 FOREIGN PATENTS 1,106,458 France Dec. 19, 1955