GB647601A - Improvements in and relating to refrigerating systems - Google Patents

Abstract

647,601. Refrigerating. BRITISH THOMSON-HOUSTON CO., Ltd. April 21, 1948, No. 11011. Convention date, April 22, 1947. [Class 29] [Also in Group XXIX] In a compression refrigerating system comprising a low temperature evaporator 3 and a higher temperature evaporator 4, refrigerant is supplied either to the evaporators in series or to the evaporator 3 only in accordance with the temperature of the evaporator 4. Liquid refrigerant from a condenser 2 flows through a capillary tube 5 to a solenoid-operated valve 8 comprising a valve member 13 the tapered ends of which' co-operate with valve seats 11, 12 feeding lines 9, 10 respectively which lead to the evaporators 3, 4 respectively. A coil 15 around the valve 8 is supplied with current when a switch 18 is closed by a bulb 19 on the evaporator 4 due to a rise in the temperature thereof. The member 13 rises and refrigerant flows to the evaporator 4 and thence through a valve 21 to the evaporator 3. The valve 21 contains a valve seat 23 co-operating with a valve member 24 actuated by a bellows 25 so as to maintain a constant pressure in the evaporator 4. The control point of the valve 21 is varied by a screw 28 acting on a bellows 27 communicating through a port 30 with the bellows 25. When the evaporator 4 is cold enough the switch 18 opens and the member 13 drops by gravity to direct refrigerant by way of pipe 9 to the evaporator 3 only. The compressor 1 is controlled in accordance with the temperature of the evaporator 3 by a bulb 34. The valve member 13 has longitudinal grooves 14 to allow passage of refrigerant therealong.