Patent ID: 7225635
Filing Date: 2007-06-05
Classification: F25B

Abstract:
1. A transition critical refrigerant cycle apparatus constituted by connecting a compressor, a gas cooler, a pressure reducing device, an evaporator and the like in an annular shape, using carbon dioxide as a refrigerant, and capable of having a supercritical pressure on a high-pressure side, the apparatus comprising: an internal heat exchanger for exchanging heat between a refrigerant which has flown out of the gas cooler and a refrigerant which has flown out of the evaporator; the internal heat exchanger having a double tube having inner and outer tubes, the high-pressure-side channel being disposed in the inner tube, and the low-pressure-side channel being disposed between the inner tube and the outer tube; wherein the internal heat exchanger comprises a high-pressure-side channel through which the refrigerant from the gas cooler flows, and a low-pressure-side channel which is disposed in a heat exchanging manner with the high-pressure-side channel and through which the refrigerant from the evaporator flows, the refrigerant being passed upwards from below in the high-pressure-side channel, and the refrigerant being passed downwards from above in the low-pressure-side channel.