Two-temperature refrigerating plant for independent freezer and cooler - has a compressor, a condenser, two self-contained evaporators for different temperature compartments and a switch over valve structure

摘要

The switch-over valve structure (5) consists of two magnetic valves. One is a two-way switch valve (6) and the other a three-way (7). Its admission is linked to the outlet (4) of the condenser (3) and its two outlets are linked via respective expansion devices (, 13) (e.g. capillary tubes) to the admissions of the evaporators (10, 14). The outlets (16, 16a) of the evaporators are linked via check valves (19, 21) in the opening suction direction to the suction pipe (17) of the compressor (1). This enables not only supply of cooling agent to each self-contained evaporator (10, 14) but also to defrost them individually by isolating each one or both of them as necessary. Each compartment (11, 15) is equipped with its own thermostat (22, 23) and its own controlled defrost device (30, 31). A main control device (26) controls the individual thermostats of both lower and higher temp. compartments, the two magnetic valves, the compressor and the defrost devices. ADVANTAGE - Each evaporator can be optimised for its own purpose. Total efficiency of refrigerator is improved and defrosting power can be lower.