US2724242A - Multiple temperature refrigerator cabinet - Google Patents

Description

Nov. 22, 1955 J. w. PULASKI MULTIPLE TEMPERATURE REFRIGERATOR CABINET Filed July 24, 1952 In ven tor- John W. ulasK His Attorney.

United States Patent Qfitice Patented Nov. 22, 1955 MULTIPLE TEMPERATURE REFRIGERATOR CABINET j John W. Pulaski, Erie, Pa., assignor to General Electric Company, a corporation of New York Application July 24, 1952, Serial No. 300,657

Claims. (Cl. 62103) This invention relates to refrigerator cabinets and, more particularly, to refrigerator cabinets having a low temperature storage compartment for the storage of frozen foods anda relatively higher temperature compartment for the storage of fresh foods.

One of the problems which has arisen in connection with multiple temperature refrigerators having a low temperature compartment and a higher temperature compartment enclosed by a single door has been the condensation of moisture on the outer surface of the separate door enclosing the low temperature compartment or evaporator. Refrigerators of the type having an evaporator extending across the entire width of the cabinet are especially subject to such condensation, which is undesirable because the moisture may drip on the foods stored in the refrigerator and is unsatisfactory from the standpoint of appearance.

Accordingly, it is an object of the invention to provide a multiple temperature refrigerator in which the condensation of moisture on the door of the low temperature compartment is substantially lessened.

A further object of the invention is to provide a refrigerator of the multiple temperature type in which moisture accumulating on the door of the low temperature compartment is evaporated and transferred to the fresh food compartment by air circulation.

Further objects and advantages of my invention will become apparent as thefollowing description proceeds and the features of novelty whichcharacterize my invention will be pointed out with particularity in the claims annexed to and forming a part of this specification.

Briefly stated, in accordance with the illustrated embodiment of my invention, a two-compartment refrigerator has been provided in which the outer cabinet door and the door of the low temperature compartment are sufiiciently spaced apart and so arranged that heated air is induced to flow along the surface of the latter door and deposit the moisture thus collected in the fresh food compartment. The upper portion of the outer door is recessed and reduced incross section to provide the necessary air space and also reduce insulation thickness in this area and thus increase the temperature gradient across the air space. The recessed portion of the outer door extends downwardly to a point below the upper edge of the fresh food compartment to permit circulation of air between that compartment and the air space between thejouter door and the door of the low temperature compartment.

For a better understanding of my invention reference may be made to the accompanying drawing the single figure of which is a side elevation view partly in cross section of a portion of a refrigerator including an embodiment of my invention. i

Referring to the drawing, the reference numeral 1 designates a refrigerator cabinet having a low temperature compartment 2 in the upper portion and a fresh food storage compartment 3in the lower portion thereof. The cabinet is provided with insulated. walls for enclose ing the low temperature and food storage compartments including top wall 4 and rear wall 5. The outer walls of the cabinet are formed by an outer metal shell 6 and inner shells 7 and 8 which enclose the .low temperature compartment 2 and the food storage compartment 3 respectively. Compartments 2 and 3 are separated by an insulated, generally horizontal wall 9. At the front of the cabinet the space between the edge of outer shell 6 and inner shell 7 is closed by heat breaker strip 10 while the space between outer shell 6 and inner shell 8 is closed by heat breaker strip 11. Separating the heat breaker strips 10 and 11 at the front edge of horizontal wall 9 is a mullion 12.

Low temperature compartment 2 is formed with a front opening which may be closed by a closure member or door 13 while the food storage compartment is also provided with an opening at the front: of the cabinet which may be closed by a door 14. It will be noted that door 14 is coextensive with the outer walls of cabinet 1 and thus serves to enclose compartment 2 as well as compartment 3. Like the outer walls of the cabinet, door 14 comprises an outer shell 15 and an inner liner 16 with insulation therebetw'een. Low temperature compartment 2 may be refrigerated by any suitable means (not shown) while food storage compartment 3 may be cooled by a fiat plate type evaporator such as evaporator 17 shown in the drawing.

In order to provide an air space 18 between outer door 14 and door 13 of compartment 2, the upper portion of inner liner 16 is recessed, as at 19, from a point adjacent the upper edge of door 13 down to a point somewhat below the lower edge of horizontal wall 9. The width of recessed portion 19 of inner liner 16 is generally the same as the width of compartments 2 and 3. Thus it is apparent that air space 18 and food storage compartment 3 are in communication with each other and that air in compartment 3 may circulate through air space 18. a

The manner in which my improved refrigerator cabinet functions to maintain the outer surface of door 13 free from condensed moisture will now be described. Such moisture tends to form each time the outer door of the refrigerator is opened, thus permitting relatively warm air to enter. Also, in some prior art refrigerators, moist air from the food storage compartment may flow upwardly along the relatively cold outer surface of the door of the low temperature compartment, thus depositing moisture thereon. In accordance with my invention, air circulation between the food storage compartment 3 and the air space 18 adjacent the door of the low temperature compartment is so controlled and directed that such condensation of moisture is substantially reduced or eliminated.

Referring to the drawing, the air circulation pattern within my refrigerator is, shown by the arrows in compartment 3 and air space 18. Because of the decreased thickness of the insulation in door 14 adjacent the recessed portion 19 of inner liner 16, a relatively large temperature gradient across air space 18 is established. This gradient will, of course, depend on the relative amounts of insulation in the door 13 and the adjacent portion of the door 14, but in any event, the temperature of recessed portion 19 will be substantially. higher than the temperature of the outer surface of door 13. Thus the layer of air along the surface of recessed portion 19 will tend to rise while the layer of air adjacent the door 13 will tend to descend.

In this manner, the circulation indicated by the arrows on the drawing will be established and air descending along door 13 and collecting condensed moisture therefrom will pass into the food storage compartment 3 and over evaporator 1'7 'where moisture absorbed from the surface of door 13 will be deposited. In other words an air circulat'ion will be set up which will first pick up the moisture from door 13 and which will then pass over a dehumidifying means, i. e. evaporator 17, to lose the moisture. Such circulation will be continuous if evaporator 17 is operated continuously ,to cool compartment 3 and intermittent if evaporator 17 operates intermittently. In either case the surface of door 13 will be maintained substantially free of condensed moisture;

It will be obvious to those skilled in the art that a number of modifications may be made within the scope of my invention. For example, a dehumidifying device might be substituted for the member designated as evaporator ll7 and food storage compartment 3 cooled by some other means such as an evaporator in contact with theouter surface of inner shell 8. Also, the thickness of the insulation in door 14 adjacent air space 18 might be reduced by increasing the depth of the recess in inner liner 16 and, in fact, such insulation might be entirely eliminated and this portion of door 14 replaced by an uninsulated metal shell.

While I have shown and described a specific embodiment of my invention, I do not desire my invention to be limited to the particular construction shown and described and I intend, by the appended claims, to cover all modifications within the spirit and scope of my invention.

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

l. A refrigerator comprising a cabinet having insulated outer walls and an intermediate horizontal wall dividing the cabinet into an upper low temperature compartment and a lower fresh food storage compartment, a closure member in the front opening of said upper compartment, dehumidifying means in said lower compartment,v and a door forming. the front wall of said cabinet and enclosing both of said compartments, the lower portion of said door adjacent said lower compartment being insulated, and the upper portion of the inner surface of said door adjacent said upper compartment having a recess providing an air space between said door and said closure member, said recess reducing the spacing between the inner and outer surfaces of said door in the upper portion thereof thereby to cause said upper portion of said inner surface to be kept relatively warm by heat leakage from said outer surface, the lower edge of said recessed portion of said door being somewhat below the lower edge of said horizontal wall, said air space being in communication with said lower compartment whereby air within aid lower compartment is caused to rise along the relatively warm recessed'portion of said door and descend along the relatively cool surface of said closure member, thus transferring moisture from said closure member to said lower compartment.

2. A refrigerator comprising a cabinet having insulated outer walls and an intermediate horizontal wall dividing the cabinet into'an upper low-temperature compartment and a lower fresh food storage compartment, a closure member in the front opening of said upper compartment, dehumidifying means in said lower compartment, and an insulated door forming the front wall of said cabinet and enclosing both of said compartments, the upper portion of the inner surface of said door adjacent said upper compartment closure member having a recess providing an air space between said door and said closure member, said recess reducing the spacing between the inner and outer surfaces of saiddoor in the upper'portion thereof thereby to cause said upper portion of said inner surface to be kept relatively warm by heat leakage from said outer surface, thelower edge of said recessed portion of said door being somewhat below the lower edge of said horizontal Wall, said airspace being in communication with said lower compartment whereby air within said lower compartment is caused to risealong the relatively warm reoessedportion of saiddoor and descend along the relatively cool surface of. said closure member thus trans- 4 ferring moisture from said closure member to said lower compartment.

3. A refrigerator comprising an insulated cabinet including top, bottom, side and rear walls and an intermediate horizontal wall dividing the cabinet into an upper lowtemperature compartment and a lower fresh food storage compartment, an insulated closure member in the front opening of said compartment, cooling means for both compartments including an evaporator mounted in the upper portion of said lower compartment, and an insulated door forming the front wall of said cabinet and enclosing both of said compartments, the upper portion of the inner surface of said door adjacent said upper compartment closure member having a recess providing an air space between said door and said closure member, said recess reducing the spacing between the inner and outer surfaces of said door in the upper portion thereof thereby to cause said upper portion of said innersurface to be kept relatively warm by'heat leakage from said outer surface, the lower edge of said recessed portion of said door being somewhat below the lower edge of said horizontal wall, said air space being in communication with said lower compartment whereby air within said compartment is caused to rise along the relatively warm recessed portion of. said door and descend along the relatively cool outer surface of said closure member to said lower compartment thus transferring any moisture condensed on said closure member to said evaporator.

4. A refrigerator comprising an insulated cabinet ineluding top, bottom, side and rear walls and an intermediate horizontal wall dividing the cabinet into an upper low temperature compartment and a lower fresh food storage compartment, an insulated closure member in the front opening of said compartment, cooling means for both compartments including an evaporator mounted in the upper portion of said lower compartment, and an insulated door forming the front wall of said cabinet and enclosing both of said compartmentmsaid door comprising an outer shell and an inner liner with insulating material therebetween, the upper portion of said inner liner adjacent said closure member being bulged outwardly to lie closer to said outer shell than does the lower portion of said inner liner so as to provide an air space between said door and said closure member, the reduced spacing between said upper portions of said inner liner and said outer shell causing said upper portion of said inner liner to be kept relatively warm by heat leakage from said outer shell, the lower edge of said recessed portion of said door being somewhat below the lower edge of said horizontal wall, said air space being in communication with said lower compartment whereby air Within said compartment is caused to rise along the relatively warm upper portion of said door and descend along the relatively cool outer surface of said closure member to said lower compartment,

thus transferring any moisture condensed on said closure member to saidevaporator.

S. A refrigerator comprising a cabinet having insulated outer walls and an intermediate horizontal wall dividing the cabinet into an upper low-temperature compartment and a lower fresh food storage compartment, a closure member in the front opening of said upper compartment, cooling means for both compartments including an evaporator in said lower compartment, and an insulated door forming thefront wall of said cabinet and enclosing both of said compartments, the upper portion of the inner surface'of said door adjacent said upper compartment closure member having a recess providing an air space between said door and said closure member, said recess reducing the spacing between the inner and outer surfaces of said door in the upper portion thereof thereby to cause said upper portion of said inner surface to be kept relatively warm by heat leakage from said outer surface, the lower edgeof said-recessed portion of said door being somewhat below the lower edge of said horizontalwall, said air' space being in communication with said lower compart ment whereby air within said lower compartment is caused to rise along the relatively warm recessed portion of said door and descend along the relatively cool outer surface of said closure member thus transferring moisture from said closure member to said lower compartment.

2,301,313 Money et a1 Nov. 10, 1942 6 Philipp Jan. 26, 1943 Tobey Oct. 16, 1945 Kruck et a1 Dec. 7, 1948 Ryan Mar. 21, 1950 Richard Apr. 24, 1951 Alsing Dec. 29, 1953

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