US2317709A - Refrigeration apparatus - Google Patents

Description

Ap '27, 1943. c. F. ALslNG REF'nLurJKATLON APPARATUS Filed Dec. 10, 1941 INVENTOR (7424 ALS/NG ATTOR Y Patented A r. 27, 1943 UNlTED STATES PATENT OFFICE REFRIGERATION APPARATUS Carl'F. Alsing, Wilbraham, Mass, assignor -to Westinghouse Electric 8; Manufacturing Company, East Pittsburgh, Pa, a. corporation of Pennsylvania Application December 10, 1941, Serial No. 422,342

Claims.

This invention relates to refrigerating apparatus and more especially to apparatus adapted to maintain a food-storage compartment at a high-humidity.

One object of' the invention is to provide a thermal storage capacity for an intermittentlyoperating refrigerating system.

Another object of the invention is. to decrease the fluctuation in the temperature of the foodstorage compartment caused by an intermittently-operating refrigerating apparatus.

Theseandother objects are effected by my innism 25 interposed in one of two leads 33 which supply the electric motor 42 in the casing 21 with vention as will be apparent from the following description and claims taken in accordance with the accompanying drawing, forming a part of this application, in which:

Fig. l is an elevation of a domestic refrigerator with parts broken away to show the refrigerating system of this invention; and

Fig. 2 is an enlarged sectional view of the thermal storage tank of this invention.

Referring to the drawing for a detailed description of the invention, the reference numeral ill designates a refrigerating cabinet comprising an outer metal 'shell' Ii. The shell is divided by a horizontal partition i2 into an upper foodstorage compartment l3 and a machine compartment l4 below the food-storage compartment l3.

1 The food-storage compartment I3 is provided with an inner metal liner l6. Heat-insulating material I1 is packed between the inner liner i6 and the upperportion of the metal shell II and the partition l2. The food-storage compartment [3 is further divided by a horizontal partition l8 into an upper low-temperature, lowhumidity compartment l9 and a high-humidity compartment 2| below the low-humidity compartment l9.

electric power. The switch mechanism 25 is of the snap-acting type and preferably'has a temperature differential of 10 Fahrenheit in order to prevent an excessive number of starts of the nects through tubes and 36 with a secondary refrigerant condenser comprising a horizontally coiled tube 31 located in the thermal storage tank 3! and spaced from the coil 29. The top area of the high-humidity compartment 2| is also refrigerated by conduction through the partition l8.

The thermal storage tank 3| contains a liquid 39, the upper level of which is indicated by the A primary refrigerant evaporator 22 is located in the low-humidity compartment and is provided with primary refrigerant liquid through a capillary tube 23 and a coil 29 from a primary refrigerant condenser 24. The condenser 24 receives compressed refrigerant vapor through a tube 26 from a compressor driven by an electric motor 42, both the compressor 4|! and the electric motor 42 being housed in a sealed casing 21. The compressor 40 withdraws refrigerant vapor through a suction tube 29 from the primary evaporator 22. The coil 29 is located in a thermal storage tank 3| and forms a second evaporator in series with the primary evaporator 22.

The refrigerating apparatus 22, 24, and 40 is operated intermittently to maintain the temperaturelof the primary evaporator 22 between, for example, 0 and 30 Fahrenheit. To this end a bulb l5 containing a volatile liquid is aiiixed in heat transfer relationship with the primary evaporator 22. The bulb l5 communicates through a tube 29 with an electric switch mechadotted'line 4|. The liquid comprises a solution of, for example, alcohol or glycerin and water, the solution preferably having a freezing point of from 15 to 25? Fahrenheit depending on the quantity of the liquid which is frozen.

Operation The coil 29 forms an evaporative cooling unit fluctuating in temperature between 0 and 30 Fahrenheit with the active and inactive periods of the primary refrigerating apparatus 22, 24, and 40. When the primary refrigerating apparatus 22, 24, and 40 is active, and the temperature of the coil 29 is below 15 Fahrenheit, portions of'the liquid 39 will freeze. During the freezing of the liquid 39, the latent heat of the frozen portion thereof is transmitted to the coil 29, so that the refrigerating efiect of'the coil 29 is not directed entirely to lowering the tem-'- perature of the secondary condenser coil 31. This keeps the unit running at higher suction pressure with better eillciency.

In like manner, when the refrigerating apparatus 22, 24, and 40 is inactive between operating The absorption of heat-from the coil 31 tends to continue its action as a condenser for the secondary refrigerant to cool the coil 34.

The full cooling efiect of the primary refriger- 'ant coil 28 is thus not transmitted toward the cooling of the secondary refrigerant coil 31 -andthe secondary refrigerant evaporator 34 during the active cycle of the refrigerating apparatus 22, 24, and I because a portion of the cooling effect surfaces, and means "for conveying heat from said secondary cooling unit to said thermal storage liquid, said thermal storage liquid having a congealing point of such temperature thata substantial portion of the liquid congeals when said means supplies said second primary cooling unit with refrigerant and melts when said means does of the coil 29 is stored by the formation of' a 1 frozen solution in the thermal storage tank 3|. During the inactive period of the refrigerating apparatus 22, 24, and 40, the frozen solution melts and absorbs heat from the. secondary refrigerant condenser 31, therebyto maintain the temperature in the high-humidity compartment 2| more uniform to overcome the effect of cycling of the refrigerating apparatus 22, 24, and 40.

The more uniform temperature of the high humidity storage compartment 2| permits of a higher humidity therein, because less of the moisture in the air of the compartment 2| is condensed on the portion of the inner liner iii of the compartment 2| during the active cycle of the refrigerating apparatus 22,24, and 40, because of the higher temperature of the inner liner during the active cycle.

It will be apparent from the above that this invention provides thermal storage for an intermittently operating refrigerating system which storage decreases the fluctuations in the tem- V perature of the high-humidity food-storage compartment and makes possible the maintenance of a higher humidity therein.

While I have shown my invention in but one form, it will be obvious to those skilled in the art that it is not so limited, but is susceptible of various changes and modifications without departing from the spirit thereof, and I desire, therefore, that only such limitations shall be placed there upon as are specifically set forth in the appended .claims.

What r claim is: 1. In refrigerating apparatus, the combination of'an insulated cabinet defining a low-humidity and a high-humidity compartment, a thermal storage liquid, a primary cooling unit for cooling the low-humidity compartment and the thermal storage liquid, means for intermittently supplying the primary cooling unit with refrigerant to maintain the temperature of said primary cooling unit between predetermined limits, a secondary evaporative cooling unit for cooling the highhumidity compartment, said secondary evaporative cooling unit having extended heat-absorbing and a condenser for said secondaryv evaporative cooling lmit, said condenser being in heat-transfer relationship with said thermal storage liquid, saldther'mai storage liquid having a congealing point of suchtemperature that a substantial portion of the liquid congeals when said means supplies the rimary cooling unit with refrigerant and melts when said means does not supply the primary cooling unit with refrigerant.

not supply the second primary cooling unit with refrigerant. o

3. In refrigerating apparatus, the combination of an insulated cabinet defining a low-humidity and a high-humidity compartment, a primary cooling unit for cooling the low-humidity compartment, a second primary cooling unit for cooling a thermal storage liquid, means for intermittently supplying said cooling units with reand primary cooling unit with refrigerant and melts when said means does not supply'the sec ond primary cooling unit with refrigerant.

4. In refrigerating apparatus, the combination of a cabinet, a metal liner therein, said cabinet defining a low-humidity and a high-humidity compartment, a primary cooling unit for cooling the low-humidity compartment, a second primary cooling unit for cooling a thermal-storage liquid, meansfor intermittently supplying said cooling units with refrigerant, a. secondary cooling unit in heat-transfer relationship with a large portion of the-metal linear of the high-humidity compartment, and means for conveying heat from said secondary cooling unit to said thermal-storage liquid; said thermal-storage liq-- uid having a congealing point of such temperature that a substantial portion of theliquid congeals when said means supplies said second pri- 2. In refrigerating apparatus, the combination of an insulated cabinet defining a low-humidity and a high-humidity compartment, 8. primary cooling lmit for cooling the low-humidity compartment, a second primary cooling unit for cooling a thermal storage liquid, means for intermittently supplying said cooling units with refrig'erant, a secondarycooling unit for cooling the high-humidity compartment, said secondary cooling unit having extended heat-absorbing mary cooling unit with refrigerant andmelts when said means does not supply the second primary cooling unitwith refrigerant.

5.\ In refrigerating apparatus, the combination of a cabinet, heat-insulating material surrounding said cabinet, a chamber located in said heatinsulating material, a thermal-storage liquidin said chamber, a partition in said'cabinetto divide,

the same into two food-storage compartments, a primary cooling zmit for cooling one of said compartments, a second primary cooling unit for cooling said thermal-storage liquid,-means for intermittently supplying said primary cooling units with refrigerant, a secondary cooling .unit for cooling the other of said compartments, said secondary cooling unit having extended heatabsorbing surfaces, and means for conveying heat from said secondary cooling unit tosa'id thermalstorage liquid, said thermal-storage liquid having a congealing point of such temperature that a substantial portion of the liquid congeals when said means supplies said second primary cooling unit with refrigerant and melts when said means does not supply said second primary cooling unit with refrigerant.

' CARL F. ALSING.

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