Patent ID: 7076968

Claim:
A refrigerant cycling device, wherein a compressor, a gas cooler, a throttling means and an evaporator are connected in serial in which a hyper critical pressure is generated at a high pressure side, and the compressor comprises an electric motor element, a first and a second rotary compression elements in a sealed container wherein the first and the second rotary compression elements are driven by the electric motor element, and wherein a refrigerant compressed and discharged by the first rotary compression element is compressed by absorbing into the second rotary compression element, and is discharged to the gas cooler, the refrigerant cycling device comprising: an intermediate cooling loop for radiating heat of the refrigerant discharged from the first rotary compression element by using the gas cooler; a first internal heat exchanger, for exchanging heat between the refrigerant coming out of the gas cooler from the second rotary compression element and the refrigerant coming out of the evaporator; an oil separating means for separating oil from the refrigerant compressed by the second rotary compression element; an oil return loop, for depressurizing the oil separated by the oil separating means and then returning the oil back to the compressor; and a second internal heat exchanger, for exchanging heat between the oil flowing in the oil return loop and the refrigerant coming out of the first internal heat exchanger form the evaporator.