| 摘要 |
PROBLEM TO BE SOLVED: To stably cool while sufficiently drawing cooling power by controlling a suction side superheat degree and an outlet side supercooling degree in response to refrigerant amounts in a condenser and an evaporator judged based on an outlet side refrigerant supercooling degree of the condenser and a suction side refrigerant superheat degree of a compressor. SOLUTION: Refrigerant amounts in a condenser 2 and an evaporator 4 are judged based on an outlet side refrigerant supercooling degree of the condenser 2 and a suction side refrigerant superheat degree of a compressor 1. As a result, when it is judged that the refrigerant amount in any of the condenser 2 and the evaporator 4 is less than a reference refrigerant amount, a valve travel of an expansion valve 3 is controlled so that the suction side superheat degree becomes a target superheat degree. When it is judged that the amount in the condenser 2 or the evaporator 4 is more than the reference amount, the travel of the valve 3 is controlled so that the outlet side supercooling degree becomes a target supercooling degree. The judging operation is executed by a controller 29. Thus, the cooling operation can be stably conducted while sufficiently putting a sealed refrigerant amount into practical use. |
