| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a binary refrigerating device capable of operating while maintaining a pressure ratio of a low order-side refrigerating cycle and a pressure ratio of a high order-side refrigerating cycle in an appropriate range with a simple configuration which does not need switching to a single-stage cycle operation even under an operating condition of the low pressure ratio. <P>SOLUTION: The binary refrigerating device is configured by thermally connecting the low order-side refrigerating cycle having a low order-side compressor 2, a cascade heat exchanger 9, a low order-side expansion valve 5, and a low order-side heat exchanger 6 with the high order-side refrigerating cycle having a high order-side compressor 11, a high order-side heat exchanger 13, a high order-side expansion valve 14, and the cascade heat exchanger, through the cascade heat exchanger. In addition, the binary refrigerating device includes a control means 50 which sets a target intermediate temperature in the cascade heat exchanger based on a set value of an exit temperature of a medium subjected to thermal exchange by the high order-side heat exchanger and further controls the low order-side compressor to be the target intermediate temperature. <P>COPYRIGHT: (C)2013,JPO&INPIT |
