US3635536A

US3635536A - Portable refrigerator utilizing a living hinge

Info

Publication number: US3635536A
Application number: US2850A
Authority: US
Inventors: Robert S Lackey; Jack D Meess; Myron Swetlitz
Original assignee: Westinghouse Electric Corp
Current assignee: CBS Corp
Priority date: 1970-01-14
Filing date: 1970-01-14
Publication date: 1972-01-18
Anticipated expiration: 1989-01-18

Abstract

This invention relates to a portable refrigerator having a lowcost cabinet of light weight and good insulating properties and includes a plastic breaker strip and plastic door which utilizes a living hinge disposed between these two elements.

Description

Unite States Patent Lackey et a1, 11911,. H, 197

[54] PORTLE REFRIGERATOR 1 References Cited lI'llULlZlNG A LIVING HlNGE UNITED STATES 1P ATENTS [721 Inventory Mikey, Pimburgh; Jack 2,839,347 6/1958 Strub ..312/214 w EXP, Mylo swam 3,009,169 11/1961 B0d116r.... ...160/231 R mevllle 0f 3,019,486 2/1962 56115011.... ...160/231 R 73 Assignee; ,Westinghouse n c -mi p 3,251,382 5/ 1966 Tatsch ..220/9 1F Sburgh, p 3,364,298 1/1968 Peters ..49/501 X 3,416,692 12/1968 Cline et a1. ....220/9 F fi J 1970 3,420,363 1/1969 Blickensderfer .220/9 F [21] Appl. No.: 2,850

Primary ExammerJames T. McCall Attorney-F. H. Henson and E. C. Arenz [52] 11.8. C1 ..31l2/214, 312/138 [51] 1m. 1131. ..A25d 111/011 57 ABSTRACT [58] Field ofSearch ..312/213,214, 138,257;

62/371, 457 331, 273; 220/9 F; 16/150; 49/DIG 2 This invention relates to a portable refrigerator having a low- 501, 504 cost cabinet of light weight and good insulating properties and includes a plastic breaker strip and plastic door which utilizes a living hinge disposed between these two elements.

12 Claims, 41 Drawing Figures PATENTEU JAN 1 8 M2 SHEET 1 [1F 2 PORTABLE REFRIGERATOR UTILIZING A LIVING HINGE BACKGROUND OF THE INVENTION 1. Field of the Invention This invention relates to a cabinet having the combination of a door frame and door having a living hinge disposed therebetween and, more specifically, relates to a low-cost refrigerator cabinet having a plastic breaker strip and door with a living hinge disposed therebetween.

2. Description of the Prior Art Although the use of small refrigerators has increased in recent years, primarily due to their use in trailers and camping vehicles, this increase has been somewhat limited due to the fact that a refrigerator of small size has had a relatively high cost relative to this size, not at all in proportion to what an expected selling price would be when compared to the selling price of a large conventional refrigerator. The primary reason for this is the fact that only a minimal amount of expense can be removed from the smaller refrigerator in its manufacture since all the operative components of a large-sized refrigerator and an insulated enclosure are still required in small refrigerators. Thus, the primary savings between a small refrigerator and a large one is the reduction in the material cost due to the smaller dimensions, required for the smaller, portable refrigerator. These reductions in material and refrigerator component cost are not significant enough to cause anexpansion of the market for small refrigerators to the extent indicated by the interest expressed by consumers in having convenience type or portable refrigerators of small size so that they can be located in the office, family room, den or. game room.

The successful construction of a low-cost refrigerator having light weight and good thermal insulation is, therefore, a prime requisite for the successful expansion of the market for such a portable unit.

SUMMARY OF THE INVENTION In accordance with the principles of this invention, a compact refrigerator is provided which includes a box formed from a single piece of foam slab polyurethane or polystyrene material having V notches so that the box can be finally formed in a square configuration. The rear of the refrigerator enclosure is closed by a similar sheet of plastic material which has been formed around the operating parts of the refrigerator system utilized to cool the interior space in the refrigerator. The front of the refrigerator enclosure is closed by a door also made of a material such as polyurethane or polystyrene. A door frame of polypropylene or polyethylene or the like has integrally attached thereto by a living hinge and, advantageously formed in the same molding operation, a one piece plastic breaker strip formed of the same material. The door is completed by the inclusion of a magnetic latch on the door frame, with a cooperating magnetic strike located behind the plastic breaker strip. Plastic studs may be passed through recesses in the corners of the foam slab box so as to hold the plastic breaker strip and rear side of the refrigerator to the foam slab box.

DRAWING DESCRIPTION FIG. l is a perspective view of the refrigerator of the invention showing the major components thereof in exploded view;

FIG. 2 is a perspective view of the refrigerator in assembled condition;

FIG. 3 is a perspective view of the unfolded foam slab making up the box portion of the cabinet; and

FIG. A is a view taken along line IV-IV oflFIG. I and showing the angular displacement of the breaker strip flange.

DETAILED DESCRIPTION OF THE DRAWINGS In accordance with the principles of this invention, a portable refrigerator I is provided having light weight and low cost, and comprising, generally, a combined door and onepiece plastic breaker strip 12, a foam slab box I l and a combined rear panel with integral refrigeration system I6. These three major components of the refrigerator may be held in assembled relationship by a series of plastic studs llfl extending through the foam slab box M and into the rear panel and plastic breaker strip, respectively.

The foam slab box I4 is formed by four

sides

20, 22 2d and 26, with the

sides

20 and 24 forming the sides of the refrigerator, the side 22 forming the top and the side 26 the bottom of the refrigerator. These four sides are integral in that they are all formed from a single sheet of polyurethane or polystyrene (FIG. 3). In the event that polyurethane is utilized for the sheet and it is formed in the chilled mold process, then no coating need be given to the inner and outer sides of the sheet 115 since this material then has a thick impervious skin adjacent its outer and inner faces and thereby is provided with a substantially impervious inner and outer face in the molding process. If polyurethane is utilized for the sheet 115, then an outer facing material must be utilized "to protect the relatively soft sheet. For example, a metal sheet of extremely thin gauge and being vinyl clad (not shown) may be provided so that the outer side of the refrigerator has a facing which has some durability.

The single sheet l5 from which the foam slab box M is formed comprises a notched slab which, before folding, has notches 17 that are V-shaped in cross section and elongated so as to extend along and between the adjacent lengths of the

sides

20, 22, 2A and 26 of the refrigerator. The ends of the sheet 15 include

bevels

19,19 that extend for the length of the adjacent sides so that the sheet 15 may be properly closed at its ends to form the foam slab box ll l. After the formation of the single sheet 15 in this manner, it is folded so that a pair of bevel faces 28 and 30, for example, formed by either the opposed faces of one of the V" notches. l7 or the bevels R9, of the sheet 115 abut to place

sides

20 and 22 in a right-angular relationship relative to each other. After completion of the formation of the square cross section of the foam slab box M, the said slab box has a fairly rigid and durable configuration, since each of the

sides

20, 22, 2d and 2s and their abutting angled faces reinforce each other and tend to maintain the foam slab box in the condition illustrated in FIG. 1. The faces formed by the bevels l9,ll9 are, of course, held in abutting relationship by an epoxy or adhesive adapted to the characteristics of either polyurethane or polystyrene material.

A front face 32 of foam slab box M provides an inwardly angled flange face along the front of each of the sides It], 22, 24 and 26 of the refrigerator I'll, these flange faces being indicated 3d, 36, 38 and 40, respectively. Each of these flange faces is disposed substantially at a 60 angle to the plane of the outer face of its respective side wall so as to provide a seating and bearing means for the easy nesting of the combined one piece plastic breaker strip and door frame 12 which are mounted thereon in the final configuration of the refrigerator Ill.

The rear panel and integral mounted refrigeration system 116 includes a foam panel 41 of polyurethane or polystyrene material which is formed in a square configuration so as to mate with the foam slab box 1d. This foam panel has an aperture 42 of generally rectangular shape through which an evaporator M extends. The evaporator 44 may conventionally be one of the operating elements of a refrigeration system 46. In the invention disclosed, it is contemplated that a typical ammonia-hydrogen, water absorption system be utilized asa part of the refrigerator lb of this invention. Such a system is relatively foolproof in operation and relatively inexpensive for small refrigeration loads. The refrigeration system as may utilize a series of coils of steel tubing or the like to form the operating elements of the system; advantageously, however, the use of an ammonia-hydrogen, water absorption system contemplates utilization of a pair of integrally connected steel panels which are pressure and heat bonded together to form the evaporator, condenser and absorber sections of the refrigeration system 46. In such an arrangement as is known in the art, each panel contains a series of configured-groove means .that are in opposed confronting relationship when the panels are integrally connected together so that the grooves form,the closed loop required for the flow of water, ammonia and hydrogen within the system. It should be pointed out that other systems than an ammonia-hydrogen, water absorption system may be utilizedto cool the configuration compartment of the refrigerator l and that the particular system utilized and-the manner of forming the closed loop does not form a part of this invention.

As previously mentioned, the combined rear panel and integral refrigeration system 16 is physically attached to the slab box 14 by means of threaded studs 18. These studs extend through bores 48 formed in the foam slab forming the rear panel 41 and through bores 49 formed by

semicircular grooves

51,51 formed in the opposed faces of the V notches 17 and the bevels 19. Nuts or the like (not shown) may be used to pull the foam panel 41 up tightly against the rear side of the foam slab box 14.

The combined one-piece plastic breaker strip and door 12 can be formed by injection molding so as to form an integral assembly including a one-piece plastic breaker strip 50, a door frame 52 and a living hinge 105. This integral unit can be conveniently formed from a material such as polypropylene since the same exhibits relatively high strength but yet has the desired resiliency to operate as a living hinge.

The plastic breaker strip 50 comprises a series of four

flange members

56, 58, 60 and 62, that are integrally connected together, the

flange members

56 and 58 forming the sides of the plastic breaker strip 50, the flange 60 forming the top and the flange 62 forming the bottom of the plastic breaker strip 50. As seen in FIG. 1 (see also FIG. 4) each of the

flange members

56, 58, 60 and 62 is provided with an angularly directed leg, each leg being indicated, respectively, 64, 66, 68 and 70. The

legs

64, 66, 68 and 70 are disposed at an angle similar to the flange faces 34, 36, 38 and 40 so as to be parallel to these faces so that these legs will seat against their corresponding faces and the

outer legs

65, 67, 69 and 71 of the flange members will seat over the

sides

20, 22, 24 and 26, with lips (e.g., lip 73) formed on the inward termination of

legs

64, 66, 68 and 70 abutting against the inside faces of

sides

20, 22, 24 and 26 to maintain the position of the plastic breaker strip 50 relative to the foam slab box 14.

The door frame 52 is also formed from a series of four

members

72, 74, 76, 78 which are joined integrally at their ends to form a substantially rectangular configuration with the

members

72 and 74 forming the sides of the door frame and the

member

76 and 78 forming the top and bottom sides of the door frame. Each of these members has a generally channel shape providing a U-shaped cross section with the bight of the U formed at an angle relative to the legs of the U-shape so as to be coincident with the angularly disposed legs of the plastic breaker strip 50. More specifically, angle faces 82, 84, 86 and 88 are formed respectively on the

members

72 and 74, 76 and 78 for their angled bights. By this arrangement a door frame 52 is provided having faces which are coincident with the legs of the plastic breaker strip to provide a nesting relationship between the door and the breaker strip when the door is closed and to yield a narrow throat clearance between the door and foam slab box 14 to decrease heat leakage.

The four faces 82, 84, 86 and 88 which form the bight of the

channel members

72, 74, 76 and 78 have directed inwardly,

legs

90, 92, 94 and 96, respectively, so as to form an inwardly directed rectangular outlined aperture within which is disposed a front sheet 98 of rectangular configuration made of foamed polystyrene or polyurethane. This element is disposed within the

channel members

72, 74, 76 and 78 and held therein by the U-shape of the channels. The sheet 98 may be easily assembled within the door frame by mere inward bending of the

legs

90, 92, 94 and 96 and the insertion of the front sheet 98 within the resiliently distended

channel members

72, 74, 76 and 78 forming the door frame 52. A series of front face, inwardly directed legs 89 (only two shown) help maintain the from sheet 98 within the door frame 52.

A boss 100 (FIG. 4) is formed in each corner of the breaker strip 50 during the injection molding process so as to threadingly receive a stud 18 within the bore 108 formed in each boss. This structural arrangement rigidly holds the breaker strip 50 against the front faces 34, 36, 38 and 40 of the foam slab box.

The living hinge means comprises a hinge which may be conveniently formed integral during the injection molding process with the. breaker strip 50 and door frame 52. This hinge takes the form of a leaflike element extending between the breaker strip 50 and door frame 52 and, more specifically, between angular leg 66 of breaker strip 50 and the angularly disposed face 84 of door frame 52. The hinge 105 is also formed of polypropylene with this material being ideal for a hinge member subject to continuous flexing since it has good strength, flexibility and long endurance.

The construction of the refrigerator 10 is completed by the addition of a magnetic latch 110 mounted on the door frame 52 so as to be in cooperative relationship with a magnetic strike 1 12 located behind the plastic breaker strip.

It will be appreciated that, although a single embodiment of the invention has been disclosed, many modifications could occur thereof to one skilled in the art without the exercise of the inventive faculty. For example, the plastic breaker strip and plastic door frame could be formed individually and then connected together with a thin sheet of resilient plastic such as polypropylene which would then form the living hinge. Such an arrangement would still yield the advantage of a lightweight, inexpensive door frame and breaker strip assembly. The thin sheet of plastic forming the living hinge, in this case, would be glued by an epoxy, or the like, to the breaker strip and door frame. Other obvious modifications could be made to the disclosure of the refrigerator illustrated and described herein which would be obvious to practitioners of the refrigeration art.

What is claimed is:

1. In a refrigerator the combination comprising;

a. a one-piece plastic breaker strip,

b. a door disposed adjacent to said plastic breaker strip,

c. said plastic breaker strip including a front flange extending angularly inwardly,

d. said door also including faces extending angularly and complementary to said angularly extending front flange on said plastic breaker strip,

e. a one-piece hinge formed of plastic and attached integrally to at last a portion of said door and said plastic breaker strip to form a living hinge therebetween so that said door may move between open and closed positions,

. said breaker strip being mounted on a foam slab plastic box, said foam slab plastic box forming the compartment for said refrigerator,

g. threaded means extending from said foam slab plastic box for connection to said plastic breaker strip, and

h. said plastic breaker strip including integral bosses for connection to said threaded means.

2. In a refrigerator the combination comprising;

a. a one-piece plastic breaker strip,

b. a doordisposed adjacent to said plastic strip,

c. said plastic breaker strip including a front flange extending angularly inwardly,-

e. a one-piece hinge formed of plastic and attached integrally to at least a portion of said door and said plastic breaker strip to form a living hinge therebetween so that said door may move between open and closed positions,

f. said breaker strip, said door and said living hinge being made of a plastic resinous material having relatively high strength, high resiliency and durability,

g. said breaker strip, a portion of said door and said living hinge being made from polypropylene,

h. said breaker strip being mounted on a foam slab plastic box, said foam slab plastic box forming the compartment for said refrigerator,

i. said foam slab plastic box being formed from a single sheet of foam plastic having notch and bevel means to enable folding formation of the box shape,

j. threaded means extending from said foam slab plastic box for connection to said plastic breaker strip, and

k. said plastic breaker strip including integral bosses for connection to said threaded means.

3. The combination set out in claim 2 wherein foam slab sheet means are provided for closing the rear of said foam slab plastic box, and (b) threaded means extend from said foam slab plastic box for connecting it to said foam slab sheet means.

4. The combination set out in claim 3 wherein said threaded means extend completely through said foam slab plastic box.

5. The combination set out in claim 4 wherein said foam slab plastic box consists of polystyrene.

6. The combination set out in claim 4 wherein said foam slab plastic box consists of polyurethane.

7. A refrigerator having;

a. a plastic breaker strip disposed at the front of said refrigerator and having an aperture therein,

b. a plastic closure member for closing said aperture,

c. a living hinge of plastic material attaching said plastic closure member to said plastic breaker strip for movement of said closure member between an open and a closed position over said aperture, and d. said plastic breaker strip, said plastic closure member and said living hinge forming a one-piece unitary assemblywhereby said refrigerator is adaptable to low-cost manufacture.

8. The refrigerator of claim 7 wherein (a) said plastic breaker strip includes a front flange extending angularly inwardly, and (b) said closure member includes faces extending angularly and complementary to said angularly extending front flange on said plastic breaker strip.

9. The refrigerator of claim 7 wherein (a) said breaker strip is mounted on a foam slab plastic box, said foam slab box forming the compartment for said refrigerator, and (b) said foam slab plastic box being formed from a single sheet of foam plastic having notch and bevel means to enable folding formation of said box shape.

10. The refrigerator of claim 9 wherein (a) threaded means extend from said foam slab plastic box for connection to said plastic breaker strip, and (b) said plastic breaker strip includes integral bosses for connection to said threaded means.

11. The refrigerator of claim 9 wherein (a) foam slab sheet I means are provided for closing the rear of said foam slab plastic box, and (b) threaded means extend from said foam slab plastic box for connecting it to said foam slab sheet means.

12. The refrigerator of claim 11 wherein said threaded means extend completely through said foam slab plastic box.

i =1 i= i

Claims

1. In a refrigerator the combination comprising; a. a one-piece plastic breaker strip, b. a door disposed adjacent to said plastic breaker strip, c. said plastic breaker strip including a front flange extending angularly inwardly, d. said door also including faces extending angularly and complementary to said angularly extending front flange on said plastic breaker strip, e. a one-piece hinge formed of plasTic and attached integrally to at last a portion of said door and said plastic breaker strip to form a living hinge therebetween so that said door may move between open and closed positions, f. said breaker strip being mounted on a foam slab plastic box, said foam slab plastic box forming the compartment for said refrigerator, g. threaded means extending from said foam slab plastic box for connection to said plastic breaker strip, and h. said plastic breaker strip including integral bosses for connection to said threaded means.

2. In a refrigerator the combination comprising; a. a one-piece plastic breaker strip, b. a door disposed adjacent to said plastic strip, c. said plastic breaker strip including a front flange extending angularly inwardly, d. said door also including faces extending angularly and complementary to said angularly extending front flange on said plastic breaker strip, e. a one-piece hinge formed of plastic and attached integrally to at least a portion of said door and said plastic breaker strip to form a living hinge therebetween so that said door may move between open and closed positions, f. said breaker strip, said door and said living hinge being made of a plastic resinous material having relatively high strength, high resiliency and durability, g. said breaker strip, a portion of said door and said living hinge being made from polypropylene, h. said breaker strip being mounted on a foam slab plastic box, said foam slab plastic box forming the compartment for said refrigerator, i. said foam slab plastic box being formed from a single sheet of foam plastic having notch and bevel means to enable folding formation of the box shape, j. threaded means extending from said foam slab plastic box for connection to said plastic breaker strip, and k. said plastic breaker strip including integral bosses for connection to said threaded means.

7. A refrigerator having; a. a plastic breaker strip disposed at the front of said refrigerator and having an aperture therein, b. a plastic closure member for closing said aperture, c. a living hinge of plastic material attaching said plastic closure member to said plastic breaker strip for movement of said closure member between an open and a closed position over said aperture, and d. said plastic breaker strip, said plastic closure member and said living hinge forming a one-piece unitary assembly whereby said refrigerator is adaptable to low-cost manufacture.

11. The refrigerator of claim 9 wherein (a) foam slab sheet means are provided for closing the rear of said foam slab plastic box, and (b) threaded means extend from said foam slab plastic box for connecting it to said foam slab sheet means.