| 摘要 |
PROBLEM TO BE SOLVED: To prevent shortage of an oil returning amount in a high stage-side compressor in a refrigerating device performing two-stage compression refrigerating cycle. SOLUTION: This refrigerating device has a refrigerant circuit 15 having a compressing mechanism 1A comprising a low stage-side compressor 21 and the high stage-side compressor 31, and performing the two-stage compression refrigerating cycle. An equal capacity control portion 101 is disposed to control an operation capacity of the compressing mechanism 1A to make a low stage-side pressure ratio and a high stage-side pressure ratio equal to each other. Further a different capacity control portion 102 is disposed for the equal capacity control portion 101 to control the operation capacity of the compressing mechanism 1A to make the low stage-side pressure ratio higher than the high stage-side pressure ratio under a prescribed operation condition. As a result, a refrigerant discharge amount from the low state-side compressor 11 is increased by the different capacity control portion 102, and simultaneously, an oil rising ratio of refrigerating machine oil stored in the low stage-side compressor 21 is increased, and the refrigerating machine oil of the low stage-side compressor 21 is supplied to the high stage-side compressor 31. COPYRIGHT: (C)2007,JPO&INPIT
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