| 摘要 |
PURPOSE:To improve a freezing capability of an evaporator and make a small-sized evaporator by a method wherein refrigerant at an outlet port of the evaporator shows a humidified condition in a freezer device comprising the evaporator having many refrigerant paths and further a liquid-gas heat exchanger having a specific double pipe structure is arranged in it. CONSTITUTION:A compressor 1, a four-way changing-over valve 2, a heat source side heat exchanger 3 acting as a condensor/evaporator during a cooling/heating operation, a heating expansion mechanism 4, a cooling expansion mechanism 6 and a utilization side heat exchanger 8 acting as an evaporator/condensor during a cooling/ heating operation are connected in sequence to constitute a refrigerant cycle. In the case that each of the heat exchangers 3 and 8 is acted as the evaporator, an amount of reduced pressure of each of the expansion mechanisms 4 and 6 is set in such a manner that refrigerant at an outlet port of the heat exchanger shows a humidified condition. In addition, a liquid-gas heat exchanger 13 of a double pipe structure comprising a suction pipe 14 (its inner diameter is Di) and a high temperature liquid refrigerant pipe 15 (its outer diameter is Do) is arranged and its size is set to have a relation of 1.1 (G/Di)<0.58>.L<0.33=Do-Di<=0.33Di, where G is a flow rate of refrigerant and L is a length of the double pipe.
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