GB1435620A - Refrigerating method and apparatus - Google Patents

Abstract

1435620 Refrigerators F KNOPSMEIER 30 Oct 1973 [30 Oct 1972] 50410/73 Heading F4H A refrigeration system for use with a transport container comprises a compression system and an absorption system having separate closed cooling circuits, the coolant of the compression system being used for cooling the coolant of the absorption system. The compression system operates when there is power available to drive the compressor and, in the absence of such power, the absorption system takes over by drawing coolant from a reservoir, passing it through an evaporator and into an absorber where it remains until it is returned to the reservoir during the next operation of the compression system. As shown, the compression system comprises a compressor 7, a condenser 9, a receiver 13, a throttle 15, an evaporator 5, a heat exchanger 17, and a cooling coil 19 in the insulated reservoir 20 of the absorption system. The absorption system comprises an absorber 21, having a heater 22, a condenser 10, the heat exchanger 17 and the reservoir 20, and employs lithium chloride as the absorbent and methyl amine as the coolant. When the power is on, the compression system operates and the cooling coil 19 maintains the condensate in the reservoir 20 at a desired low temperature. During this time, the heater 22 operates and drives off gaseous coolant from the absorber 21 to the condenser 10 and heat exchanger 17, the resulting condensate passing to the reservoir 20. If the power supply fails or is disconnected, liquid coolant passes from the reservoir 20 to the throttle 28 and evaporator 4 and thence to the absorber 21 where it is absorbed. For rapid storage of coolant in the reservoir 20, or when coolant passing through the heat exchanger 17 from the evaporator 5 has insufficient cooling capacity, condensate is drawn from the line 12 between the condenser 9 and receiver 13 and passed through a throttle 31, controlled by a thermostat 32, to the heat exchanger 17 where it evaporates and cools the coolant of the absorption system and then passes through the coil 19 back to the compressor. The compressor may be switched on and off by a thermostat in the chamber 2 which thermostat may also control valves upstream of the throttles 15 and 28. The compressor may be switched off by level switches in the receiver 13 or reservoir 20. A magnetic valve may be provided in the riser pipe 27 from the reservoir and arranged to be closed when the compressor is operating. In a second embodiment, Fig. 2 (not shown), the absorber is heated by hot coolant passing from the compressor to the condenser. Constructional details of two absorbers are described and illustrated, Figs. 3, 4 (not shown).