US3115020A - Refrigerating apparatus - Google Patents

Description

1963 J. J- PREOTLE ETAL 3,115,020

REFRIGERATING "APEARATUS Filed June 26, 1961 2 shee'hs sheet 1 I L n: {6

IN VEN TORS I John J Preozle Charles [I {-11 o) 6* V at THEIR ATTORNEY United States Patent 3,115,020 REFRIGERATING APPARATUS John J. Preotle and Charles E. Rembold, Dayton, Gino, assignors to General Motors Corporation, Detroit, Mich., a corporation of Delaware Filed June 26, 196i, Ser. No. 119,518 4 Claims. (til. 62-275) This invention pertains to refrigerating apparatus and more particularly to foam insulated refrigerators and freezers.

High quality foam insulation has such improved insulation value that the wall thickness of refrigerators can be greately reduced and the size of the interior increased to provide a much larger storage space without increasing the size of the exterior shell. Since such high quality foam insulation is ordinarily not fireproof, especial precautions must be taken if electric wiring is embedded in the foam insulation. Furthermore, if wiring were embedded in the foam insulation, the wiring could not be readily removed for inspection or repair without seriously diminishing the insulation properties of the refrigerator. Also, if the refrigerant conduits were passed through the foam insulation, they could not be readily removed when desired to remove the entire refrigerating system from the cabinet. This would either prevent the use of a permanently sealed refrigerating system or it would substantially prevent the removal of such a refrigeration system from the cabinet.

It is an object of this invention to provide a foam insulated refrigerator arranged .in such a way that the wiring is kept a safe distance away from the foam insulation and is readily removable and accessible.

It is another object of this invention to provide a foam insulated refrigerator arranged in such a way that the wiring is surrounded by noninflammable materials some of which are sufficiently resilient to permit ready inspection, removal and replacement.

It is another object of this invention to provide a foam insulated refrigerator arranged in such a way that the refrigerant conduits are not embedded in the foam insulation but are depressed into a resilient insulation material from which they are readily removable.

These and other objects are attained in the form shown in the drawings in which the space between the inner and outer shells irrnnediately around the door opening is filled with an especially resilient fireproof electrically non-conductive Fiberglas type of insulation in the form of strips. The wiring including low wattage heater wire surrounding this portion of the cabinet is removably fastened to the inner surface of the outer shell by means of adhesive tape and is located adjacent to this resilient insulation for the purpose of preventing condensation on the outer shell adjacent the door. The refrigerating system is arranged so that the conduits extending from the liquefying means in the machinery compartment extend through the strips of Fiberglas insulation to the avaporan ing means within the inner shell. Preferably, these conduits are depressed into the surface of the resilient Fiberglas material. The remainder of the space between the inner liner and outer shell is filled with a high quality foam insulation allowing relatively thin walls to be used which will have a high insulating value.

Further objects and advantages of the present invention will be apparent from the following description, reference being had to the accompanying drawings wherein a preferred embodiment of the present invention is clearly shown.

In the drawings:

FIGURE 1 is a front view of a frozen storage refrigerator embodying one form of my invention;

FIGURE 2 is a fragmentary enlarged vertical sectional 3,115,020 Patented Dec. 24., 1963 View taken substantially along the line 22 of FIG- URE 1;

FIGURE 3 is a fragmentary horizontal sectional View taken along the line 3--3 of FIGURE 1; and

FIGURE 4 is a fragmentary horizontal sectional view taken along the line 44- of FIGURE 1.

Referring now to the drawings, there is shown a refrigerator cabinet 20' including an outer shell 22 provided with a removable back wall 24 fastened in place by screws 26. The front wall 28 of the outer shell has an inwardlyturned U-shaped reinforcing flange 30 extending completely around the opening '32 for the insulated front door 34. To prevent sweating of the outer shell 22 around the door opening 32, there are provided low wattage heater wires 36 which are removably fastened at intervals tothe inner surface of the outer shell all around the door opening by adhesive tape. Held in position over the heater wires 36 by the U-shaped in-turned flanges 3% are strips 38 of an especially resilient fireproof, electrically non-conductive type of Fiberglas, known as the A-F type. This Fiberglas insulation 38 holds the wiring in place in the event that the adhesive tape should come loose or be damaged by the heat from the heater wire 36.

The inner liner 40, preferably of metal, is supported by the substantially rigid high quality foam insulation 42 which substantially fills all the space behind the strips of Fiberglas insulation 38. Because of its structural strength, the foam insulation 4-2 eliminates the need for any supporting brackets for the inner liner 4%. Because of its high insulating value, the walls may be made relatively thin. The foam insulation material 42 may be introduced between the outer shell 22 and the inner liner .0 after the Fiberglas strips 33 have been placed and after the heater wires 36 are in place. At this time, the inner liner til will be supported in proper position by a suitable fixture and the foam insulation applied through the open rear wall of the outer shell 22. After the foam material has been introduced into the insulation space, the rear wall 24 is then applied and fastened in place by the screws 26.

The refrigerant liquefying apparatus is provided in a machinery compartment 44 located beneath the insulated walls surrounding the inner liner 40. In the machinery compartment 44 is located the sealed motor compressor unit as provided with a suction conduit '48 and also conneoting through a discharge conduit with the condenser 50. According to my invention, the condenser 50 connects to a capillary restrictor tube 52 which together with the suction conduit 48 extends through a notch 54 in the front wall immediately beneath the right side of the door opening 32. This notch is normally covered by the front door 34. After passing through the notch 54, the suction conduit 48 and the capillary tube 52 depress a groove and extend within the groove or depression so formed in the strip 38 of resilient Fiberglas insulation extending across the bottom of the door opening 32. The suction conduit 48 and the capillary tube 5-2 then extend through a notch in the in-turned flange at the front of the inner liner iii to the evaporator '56 located beneath the false bottom wall 58 in the bottom of the inner liner 40. The refrigerant conduits, namely, the suction conduit 4-8 and the capillary tube 52, as well as the strips of Fiberglas insulation 38, are covered by the plastic breaker strips of which are readily removable and preferably snap into place.

The false bottom wall 58 encloses an evaporator compartment 62 between it and the bottom wall of the inner liner to. The evaporator 56 is located in this evaporator compartment 62. Air from the main storage space 64, enclosed by the inner liner 40, enters the evaporator compartment 62 through a plastic grille having two rows of openings 65 located beneath the front edge of the false bottom wall 58 as shown in FIGURE 2. Air is removed from the rear of the evaporator compartment 62 by a fan (not shown) which discharges upwardly through a duct 68 to the upper portion of the compartment 64 so as to recirculate the air therein. Through rapid circulation of the air, the air in the compartment 64 is kept at a desired frozen storage temperature, such as between 5 and F. This temperature is maintained by providing in electrical series circuit with the motor-compressor unit 46 a thermostatic control switch 70 within the machinery compartment having a capillary tube 72 extending through the notch 54 and the adjacent strip 38 of Fiberglas insulation material to the second return bend on the adjacent side of the evaporator 56. The up-turned lower front flange of the inner liner is provided with an aperture through which the capillary tube 72 extends. The end of the capillary tube is preferably clamped to the return bend 74 by conventional means.

During the pouring of the foam, the strips 38 of resilient Fiberglas insulation prevent the leakage of escape of the materials forming the foam insulation. The strips 38 are very resilient and firesafe and, when the breaker strip molding 60 is removed, can be readily removed and replaced at any time desired. The removal of the strips 38 exposes the wiring 36 for inspection and repair. The refrigerating system comprising the liquefying apparatus and the evaporator 56 can be readily removed as a unit since the refrigerant conduits intervening rest in the lower Fiberglas strip 38 and are not permanently fastened in any way to the cabinet. The refrigerator switch 70 and its capillary tube 72 can likewise be readily removed from the cabinet.

While the embodiment of the present invention, as herein disclosed, constitutes a preferred form, it is to be understood that other forms might be adopted.

What is claimed is as follows:

1. A refrigerator including spaced inner and outer sheet metal walls enclosing a storage compartment and provided with a door opening for access to said compartment, the periphery of said door opening having at least a portion provided with a resilient insulation material, a refrigerant evaporating means surrounded by said inner walls, a refrigerant liquefying means located outside said outer walls, refrigerant conduit means connecting said liquefying and evaporating means having a portion depressed within said resilient insulation material, a cover for said resilient insulation material, and a substantially rigid foamed plastic insulation material supporting said resilient material and extending between and bonded to and providing a structural connection between said inner and outer walls behind said resilient material.

2. A refrigerator including spaced inner and outer sheet metal walls enclosing a storage compartment and provided with a door opening for access to said compartment, the pheriphery of said door opening having at least a portion provided with a resilient insulation material, a refrigerant evaporating means surrounded by said inner walls, a refrigerant liquefying means located outside said outer walls, an electrical wiring system having a portion directly associated with said resilient insulation material and a portion connected to said liquefying means, said liquefying and evaporating means being operatively connected, a cover for said resilient insula tion material, and a substantially rigid foamed plastic insulation material supporting said resilient material and extending between and bonded to and providing a structural connection between said inner and outer walls behind said resilient material.

3. A refrigerator including spaced inner and outer sheet metal walls enclosing a storage compartment and provided with a door opening for access to said compartment, the periphery of said door opening having at least a portion provided with a resilient insulation material, a refrigerant evaporating means surrounded by said inner walls, a refrigerant liquefying means located outside said outer walls, an electrical wiring system having a portion directly associated with said resilient insulation material and a portion connected to said liquefying means, refrigerant conduit means connecting said liquefying and evaporating means having a portion depressed within said resilient insulation material, a cover for said resilient insulation material, and a substantially rigid foamed plastic insulation material supporting said resilient material and extending between and bonded to and providing a structural connection between said inner and outer walls behind said resilient material.

4. A refrigerator including spaced inner and outer sheet metal Walls enclosing a storage compartment and provided with a door opening for access to said compartment, said outer sheet metal walls including inwardly turned flange portions at said door opening, the periphery of said door opening having at least a portion provided with resilient insulation material in strip form supported by said inwardly turned flange portions, a refrigerant evaporating means surrounded by said inner walls, a refrigerant liquefying means located outside said outer walls, refrigerant conduit means connecting said liquefying and evaporating means having a portion depressed within said resilient insulation material, a cover for said resilient insulation material, and a substantially rigid foamed plastic insulation material supporting said resilient material and extending between and bonded to and providing a structural connection between said inner and outer Walls behind said resilient material.

References Cited in the file of this patent UNITED STATES PATENTS 2,653,139

Claims (1)

1. 3. A REFRIGERATOR INCLUDING SPACED INNER AND OUTER SHEET METAL WALLS ENCLOSING A STORAGE COMPARTMENT AND PROVIDED WITH A DOOR OPENING FOR ACCESS TO SAID COMPARTMENT, THE PERIPHERY OF SAID DOOR OPENING HAVING AT LEAST A PORTION PROVIDED WITH A RESILIENT INSULATION MATERIAL, A REFRIGERANT EVAPORATING MEANS SURROUNDED BY SAID INNER WALLS, A REFRIGERANT LIQUEFYING MEANS LOCATED OUTSIDE SAID OUTER WALLS, AN ELECTRICAL WIRING SYSTEM HAVING A PORTION DIRECTLY ASSOCIATED WITH SAID RESILIENT INSULATION MATERIAL AND A PORTION CONNECTED TO SAID LIQUEFYING MEANS, RE-

Images