Patent GB-986401-A (GB)
Title: Convertible food storage cabinet
Inventor: FOSTER LAWRENCE HAROLD
IPC: F25D17/06
Filed: 1962-01-01
Abstract: 986,401. Refrigeration; hot closets. FOSTER REFRIGERATOR CORPORATION. Jan. 1, 1962, No. 64/62. Headings F4H and F4W. In a system for producing different temperatures in a food storage compartment in a range from below 0‹ F. to above 200‹ F. including an electric heating element and a refrigerant evaporator coil in the compartment, the evaporator coil forming part of a compressor refrigeration system including a refrigerant metering valve and a solenoid-operated control valve, the required temperature is selected by a switch associated with an electric control circuit having branches connected to the refrigerant compressor and valve-operating solenoid and to the heating element, each circuit branch including a thermostatic switch set to operate at a particular temperature. As shown, the cabinet 10, Fig. 1, has two storage compartments 11, 12 which may be set independently to different temperatures. Each compartment has recessed tracks 18, 19 to receive a food-carrying cart, e.g. as described in Specification 943,675 through the door 15 or 16. The separating partition 14 is offset, Fig. 2, to form recesses 20, 21 which contain the heat transfer units for compatments 11, 12 respectively. The recesses are covered by baffles 22, 23 so as to form flues having lower openings 24 and upper circular openings containing fans 26, 26<SP>1</SP>... Refrigerating system.-Each heat transfer unit 27, 27<SP>1</SP> comprises an evaporator coil 31, Fig. 3, and electric heating element 32 having fins 30 attached thereto. The two evaporator coils are connected in parallel in a refrigerating circuit which comprises a compressor 33, condenser 34, liquid receiver 35, normally closed solenoid-operated valves 42, 42<SP>1</SP> and thermostatically controlled metering valves 46, 46<SP>1</SP>. The evaporator coils are connected to superheating coils 41 which ensure complete evaporation of the refrigerant before it is returned to the compressor. Electric control circuit; defrosting.-The temperature in each compartment is selected by a switch such as 50<SP>1</SP>, Fig. 1, which, as described, has three positions corresponding to freezing, cooling and heating, the switch setting being indicated by a corresponding coloured lamp 55<SP>1</SP>, 56<SP>1</SP> and 57<SP>1</SP> on the front of the cabinet. For freezing and cooling the valve 42 or 42<SP>1</SP>, Fig. 3, corresponding to the compartment is opened and the compressor is switched on, the temperature being controlled by associated thermostatic switches 43 or 43<SP>1</SP> for freezing and 44 or 44<SP>1</SP> for cooling. If the compartment is set for freezing, a timing circuit is operative to cause defrosting say every 12 hours; during a defrosting period the compressor and fan are stopped and the associated electric heater is energized. If the compartment is set for heating, the electric heater is energized, the temperature being controlled by thermostatic switch 45 or 451 which may be manually adjusted by a screw such as 45g<SP>1</SP> on the inside of the cabinet. A detailed control circuit is described and illustrated (Figs. 4-7, not shown).