| 摘要 |
PURPOSE:To prevent the seizing trouble of a variable capacity type compressor by a method wherein the full-load operation of the variable capacity type compressor is continued until the temperature of the delivery cavity thereof becomes lower than a predetermined value and other compressors are stopped when at least one set of the variable capacity type compressor is employed among a plurality of compressors and the temperature of the delivery cavity of the variable capacity type compressor has become higher than the predetermined value during the simultaneous operation of the compressors. CONSTITUTION:When a refrigerating load is reduced during the simultaneous operation of a variable capacity type compressor 30A and a constant capacity type compressor 30B, the capacity of the variable capacity type compressor 30A is reduced and the temperature of the delivery cavity thereof is increased. When a temperature detected by a sensor 38 exceeds a set value, the command of a controller 40 is outputted to driving motors 39A, 39B and the compressor 30A is operated with full load but the compressor 30B is stopped. According to this operation, the speed of refrigerant gas in the delivery cavity of the compressor 30A is increased and the temperature of the delivery cavity of the same is reduced gradually. When the temperature of the same cavity has become lower than the set value, operation in accordance with a refrigerating load is effected by the compressors 30A, 30B. According to this method, seizing and the like, which are accompanied by the overheating of the delivery cavity of the variable capacity type compressor, can be prevented. |
