US2688234A - Heating device for refrigerator temperature controls - Google Patents

Description

Sept. 7, 1954 c. D. HARRIS 2,688,234

HEATING DEVICE FOR REFRIGERATOR TEMPERATURE CONTROLS FiledApril 12, 1952 Patented Sept. 7, 1954 HEATING DEVICE FOR REFRIGERATOR TEMPERATURE CONTROLS Charles D. Harris, Evansville, Ind., assignor to International Harvester Company, a corporation of New Jersey Application April 12, 1952, Serial No.- 281,985

Claims.

This invention relates generally to refrigeration apparatus and more particularly to a device for heating the temperature control unit of a refrigerator cabinet.

The majority of the refrigerator cabinets being manufactured today are provided with a temperature control unit which automatically regulates the operation of the refrigeration system so that the interior of the cabinet will be maintained within a desired temperature range. The temperature control unit is generally located between the inner liner and outer shell of the cabinet in such a position that it can be easily reached for manual adjustment. In many instances, the outer casing of the temperature control unit will be cooled by the transfer of heat to the cold surfaces of the inner liner which results in the formation of condensate or frost on the outer surfaces of the unit. This condition prevents proper operation of the temperature control unit whereby the food storage compartment will not be maintained at the required temperature. The present invention provides a means for overcoming this problem.

One object of the present invention is to provide means for preventing condensateor frost from collecting on a temperature control unit.

Another object of the present invention is to provide means for supplying heat to a temperature control unit from the refrigeration system of a refrigerated cabinet.

A further object of the invention is to position amember of a refrigeration system in close proximity to a temperature control unit whereby said unit will be heated by the high pressure refrigerant within said member.

A still further object of the invention is to provide a refrigerated cabinet with a refrigeration system having a condenser and an evaporator connected by a conduitwhich is disposed with a portion thereof in heat exchange relation to a temperature control unit.

The foregoing and numerous other objects will appear from the following detailed description of preferred embodiments of the invention when considered in connection with the accompanying drawings, in which:

Fig. 1 is a perspective view of a refrigerated cabinet in which the present invention is incorporated.

Fig. 2 is a diagrammatic view of thgrefrigeration system for the refrigerated cabinet shown in Fig. 1.

Fig. 3 is a front elevational view of the refrigerated cabinet showing a modified form of the invention.

Fig. 4 is an enlarged sectional view taken along line 4-4 of Fig. 1..

Fig. 5 is an enlarged sectional view taken along line 55 of Fig. 3.

Referring to the drawings for a detailed description of the invention, a refrigerated cabinet is designated by reference numeral I 0. Although the cabinet I0 is illustrated in the form of a vertical type household refrigerator, it is to be understood that this is for illustrative purposes only and that the invention as described hereinafter is not to be limited to such a cabinet. An inner liner II is spaced within an outer shell I2 with insulating material It therebetween. The inner liner I I forms a food storage compartment I4 and a door I5 is hinged to the cabinet Ii which closes and seals the food storage compartment when in a closed position. The compartment I4 may be provided with shelves I6 and drawers I! to facilitate the storage of food articles. An evaporator I8 is secured in the upper corner of the compartment I4 over which air within the compartment I Al will circulate and be cooled.

The outer edges of the inner liner II are provided with inturned flanges I9 which project toward the outer shell I2. The edges of the outer shell I2 are provided with flanges 20 which eX- tend inwardly toward the inner liner II. The space between the edges of the inner liner I i and outer shell I2 is covered by an upper breaker strip 2 I, a lower breaker strip 22 and side breaker strips 23 and 24. The breaker strips bridge across the flanges I9 and 20 and are secured thereto by clips or other suitable means. By constructing the breaker strips from a heat insulating material, the transfer of heat between the inner line I I and outer shell I2 will be reduced substantially. The upper breaker strip 2| is provided with a circular opening 25 therethrough to which a temperature control device 26 is secured.

Details of the temperature control device 26 are not shown since the device could be any one of the many types available on the market today. The temperature control 26 is positioned in a compartment 21 provided within the insulating material I 3' and is attached to a U-shaped bracket 28 having the ends 29 and 30 thereof secured to the breaker strip H by any suitable means such as the snap spring 3I. A control knob 32 fits within the circular opening 25 and is fixedly secured to a shaft 33 which projects from the temperature control 26. A small diametered tube 3 1 connects the temperature control 26 to a control bulb 35 which is disposed within the food storage compartment I4. Any change in temperature of the compartment I4 will be registered on "the 3 temperature control 28 by the bulb 35 and tube 34.

The refrigeration system for the cabinet ll] is diagrammatically represented in Fig. 2 of the drawings. It comprises a motor-compressor unit 36, a condenser 31 and the evaporator I8. After being compressed by the motor-compressor unit 36, the refrigerant is conveyed to the condenser 31 by a conduit 39. As the refrigerant flows through the condenser 31, it is cooled and condensed, then forwarded through tube 40 to a capillary tube 41. The refrigerant is metered into the evaporator [8 by the capillary tube 41 and then returned to the motor-compressor unit 36 by conduit 42. The motor-compressor unit 36 is energized by a suitable electric circuit (not shown). The temperature control device 26 is connected into the electric circuit by leads 43 and 44 in such a manner that the compressor unit 36 will be started and stopped whenever the bulb 35 is subjected to predetermined temperatures.

A preferred embodiment of the invention is illustrated in Figs. 2 and 4 of the drawings. The tube 40 extends from the condenser 31 adjacent the inturned flange 20 of the outer shell l2 into the compartment 21 within the insulating material l3. In the illustration the tube 40 is provided with a looped portion 45 which encircles the temperature control unit 26. The food storage compartment [4 will be maintained at a low temperature by the evaporator l8 and heat leakage will cause the casing of the temperature control unit 21 to be cooled to the dew point of the air. If this condition prevailed, moisture or frost would collect on the outer surfaces of the temperature control unit 26 and prevent the unit from functioning properly. The purpose of the tube 40 is to prevent the formation of condensate or frost on the temperature control unit 26. The refrigerant which flows through the tube 40 is maintained at a high temperature and pressure by the refrigeration system. Heat from the refrigerant will be emitted by the looped portion 45 of the tube 40. Since the temperature control unit 26 is surrounded by the looped portion 45, it will be heated thereby to a temperature above the dew point of the air within compartment 21 so that the problem of condensation thereon will be eliminated. In the drawings the tube 40 is illustrated as having one turn encircling the temperature control unit 26 but it is to be understood that a greater number of turns may be provided if required.

A second embodiment of the invention is shown in Figs. 3 and of the drawings. In this structure the tube 40 is provided with an offset portion 46 to which the temperature control unit 26 is secured by means of a, clip 41. As best seen in Fig. 5, the clip 41 comprises a curved portion 48 and end portions 49 and 50. The clip is positioned with the curved portion 48 over the tube 40 and the end portions 49 and 50 contacting said unit 26 and being secured thereto by appropriate means. The tube 40 and temperature control unit 26 are held in heat exchange relation whereby the temperature control 26 will be heated by the hot refrigerant being circulated through the tube 40. This will heat the outer surfaces of the temperature control unit 26 above the dew point temperature of the surrounding air so that there will be no moisture condensed thereon.

The invention illustrated and described provides an effective means for preventing the accumulation of condensate or frost on the temperature control device 26 of the refrigerator cabinet Ill. The tube 40 serves to heat the temperature control 26 as well as to convey refrigerant from the condenser 31 to the evaporator 3 so that a complicated structure is not required for proper operation of the refrigeration system.

While the forms of embodiments of the present invention as herein disclosed constitute preferred forms, it is to be understood that other forms might be adapted without departing from the spirit of the invention or from the scope of the appended claims.

What is claimed is:

1. In a refrigerated cabinet having an inner liner spaced within an outer shell with insulating material disposed therebetween, a refrigeration system comprising a compressor, condenser, evaporator and metering device, said evaporator being located within a storage chamber enclosed by said inner liner, a temperature control unit located in close proximity to said storage chamber for controlling the operation of said compressor, a tube connecting said condenser to said metering device, said tube having a portion located in heat exchange relation to said temperature control unit whereby the unit will be maintained at a temperature above the dew point of the surrounding air.

2. In a refrigerated cabinet having an inner liner spaced within an outer shell with insulating material disposed therebetween, a refrigeration system comprising a compressor, condenser, evaporator and metering device, said evaporator being located within a storage chamber enclosed by said inner liner, a compartment provided within said insulating material, a temperature control unit positioned in said compartment for controlling the operation of said compressor, a tube connecting said condenser to said metering device, said tube having a portion located in heat exchange relation to said temperature control unit whereby the unit will be maintained at a temperature above the dew point of the surrounding air.

3. In a refrigerated cabinet having an inner liner spaced within an outer shell with insulating material disposed therebetween, a breaker strip bridging between said outer shell and said inner liner, a refrigeration system comprising a compressor, condenser, evaporator and metering device, said evaporator being located within a storage chamber enclosed by said inner liner, 2. compartment provided within said insulating material proximate said breaker strip, a temperature control unit positioned in said compartment for controlling the operation of said compressor, a tube connecting said condenser to said metering device, said tube having a portion extending through said compartment in heat exchange relation to said temperature control unit so that the unit will be heated by the tube and maintained at a temperature above the dew point of the surrounding air.

4. In a refrigerated cabinet having an inner liner spaced within an outer shell with insulating material disposed therebetween, a refrigeration system for cooling a storage chamber enclosed by said inner liner, a temperature control unit located between said inner liner and said outer shell for controlling the operation of said refrigeration system, a tube connected into said refrigeration system so that compressed refrigerant flows therethrough, said tube having a curved portion which extends around a portion of said temperature control unit in close proximity thereto whereby the unit will be maintained at a temperature above the dew point of the surrounding air.

5. In a refrigerated cabinet having an inner liner spaced within an outer shell with insulating material disposed therebetween, a refrigeration system comprising a compressor, condenser and evaporator which is located within a storage chamber enclosed by said inner liner, a compartment provided within said insulating material, a temperature control unit positioned in said compartment for controlling the operation of said compressor, a tube connecting said condenser to said evaporator, said tube having a looped portion which encircles said temperature control unit whereby the unit will be heated and maintained at a temperature above the dew point of the air in said compartment.

6. In a refrigerated cabinet having an inner liner spaced within an outer shell with insulating material disposed therebetween, a refrigeration system comprising a compressor, condenser and evaporator which is located within a storage chamber enclosed by said inner liner, a compartment provided within said insulating material, a temperature control unit positioned in said compartrnent for controlling the operation of said compressor, a tube connecting said condenser to said evaporator, and clip means for securing said temperature control unit in thermal contact with said tube whereby the unit will be heated and maintained above the dew point temperature of the air in said compartment.

7. In a refrigerated cabinet, an outer shell and an inner liner spaced therein with insulating material therebetween, a refrigeration system for cooling a food compartment enclosed by said inner liner, said refrigeration system including a continuous length of tubing having a refrigerant flowing therethrough, said refrigerant flowing therethrough having a temperature relative to the temperature of said length of tubing to cause said length of tubing to be heated by said refrigerant, a thermostatically operated device secured to said cabinet for controlling the operation of said refrigeration system, a portion of said length of tubing positioned in a contiguous relationship to said thermostatically operated device, whereby said thermostatically operated device is in a heat exchange relationship with and is heated by said length of tubing, whereby said thermostatically operated device will be maintained at a higher temperature than said food compartment.

8. In a refrigerated cabinet having an inner liner spaced within an outer shell with insulating material disposed therebetween, a refrigeration system for cooling a storage compartment enclosed by said inner liner, a thermostatically operated temperature control unit located between a wall of said inner liner and a wall of said outer shell for controlling the operation of said refrigeration system, said refrigeration system including a continuous length of tubing having a refrigerant flowing therethrough, said refrigerant flowing through said length of tubing having a temperature relative to the temperature of said length of tubing to cause said length of tubing to be heated by said refrigerant, a portion of said length of tubing positioned in a contiguous relationship to said thermostatically operated temperature control unit, whereby said thermostatically operated temperature control unit is in a heat exchange relationship with and is heated by said length of tubing, whereby said thermostatically operated temperature control unit will be maintained at a higher temperature than said storage compartment.

9. In a refrigerated cabinet having an inner liner spaced Within an outer shell with insulating material disposed therebetween, a refrigeration system for cooling a storage chamber enclosed by said inner liner, a compartment provided in said insulating material, a thermostatically operated temperature control unit positioned in said compartment for controlling the operation of said refrigeration system, said refrigeration system including a continuous length of tubing having a refrigerant flowing therethrough, said continuous length of tubing positioned in a portion of said refrigeration system wherein a warm refrigerant is caused to flow through said length of tubing, whereby said length of tubing is heated by said refrigerant flowing therethrough, a portion of said length of tubing positioned in a contiguous relationship to said thermostatically operated temperature control unit, whereby said thermostatically operated temperature control unit is in a heat exchange relationship with and is heated by said length of tubing to a degree wherein the thermostatically operated temperature control unit will be maintained at a temperature above the dew point of the air within said compartment.

10. In a refrigerated cabinet having an inner liner spaced within an outer shell with insulating material disposed therebetween, a refrigeration system for cooling a storage chamber enclosed by said inner liner, a thermostatically operated temperature control unit positioned between said inner liner and said outer shell for controlling the operation of said refrigeration system, said refrigeration system including a continuous length of tubing having a refrigerant flowing therethrough, said refrigerant flowing through said continuous length of tubing having a temperature relative to the temperature of said length of tubing such as to cause said length of tubing to be heated by said refrigerant, a portion of said length of tubing positioned in a continguous relationship to said thermostatically operated temperature control unit, and means for securing said thermostatically operated temperature control unit to said contiguous portion of said tube wherey said thermostatically operated temperature control unit will be heated by said contiguous portion of said tube, and whereby said thermostatically operated temperature control unit is maintained at a temperature above the dew point of the surrounding air.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date Re 20,2 15 Hoffman June 12, 1937 1,852,707 Hoffman Apr. 5, 1932 2,060,774 Zurcher Nov. 10, 1936 2,135,091 Newill Nov. 1, 1938 2,163,698 Money June 27, 1939 2,207,125 Kuebler July 7, 1940 2,391,030 Morrison Dec. 18, 1945 2,471,448 Platon May 31, 1949 2,477,055 Gifford July 26, 1949 2,598,335 Alsing May 27, 1952 2,598,408 McCloy May 27, 1952

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