Abstract: A refrigeration system including a two-stage type compressor having independent low-pressure and high-pressure compressing portions, a heat-releasing device having independent primary and secondary heat-releasing paths, an expansion valve and a cooler. The refrigerant primarily compressed by the low-pressure compressing portion is primarily released in heat by the primary heat-releasing path. The primarily heat-released refrigerant is secondarily compressed by the high-pressure compressing portion. The secondarily compressed refrigerant is secondarily released in heat by the secondary heat-releasing path to thereby obtain a low-temperature and high-pressure refrigerant. The low-temperature and high-pressure refrigerant is decompressed and expanded by an expansion valve and passes through the cooler to absorb the heat in a room air, and then returns to the low-pressure compressing portion of the compressor. In this system, the refrigerant temperature during the heat-releasing procedure can be kept low.

Abstract: A vehicle air-conditioning apparatus in which supercritical refrigerant passing through a refrigerant heat releasing passage of a heat releasing device exchanges heat with refrigerant cooling air introduced from an air introduction surface of a heat releasing device to be cooled, and the cooled refrigerant exchanges heat with air to be introduced into a passenger compartment by an evaporator. Since at least a part of discharge air discharged from an inside of a passenger compartment is introduced from an air introduction surface of the heat releasing device as a ventilation loss utilizing air, ventilation loss utilizing air can be used as a part of refrigerant cooling air. The ventilation loss utilizing air is introduced to the downstream side area of the refrigerant heat releasing passage in an air introduction surface of the heat releasing device.

Abstract: An evaporator using a CO2 refrigeration that prevents a raise in vapor quality of refrigeration in an evaporator passage to obtain heat exchanging efficiency. The evaporator for use in a refrigeration system includes a refrigerant inlet for introducing a refrigerant, a refrigerant outlet for discharging the refrigerant, and an evaporator passage for causing the refrigerant introduced via the refrigerant inlet to evaporate and leading the refrigerant to the refrigerant outlet. An intermediate outlet is provided at an intermediate portion of the evaporator passage. A refrigerant high in vapor quality among the refrigerant passing through the intermediate portion from the refrigerant inlet flows out of the intermediate outlet to prevent a raise in vapor quality of refrigerant.

Abstract: A refrigeration system including a two-stage type compressor having independent low-pressure and high-pressure compressing portions, a heat-releasing device having independent primary and secondary heat-releasing paths, an expansion valve and a cooler. The refrigerant primarily compressed by the low-pressure compressing portion is primarily released in heat by the primary heat-releasing path. The primarily heat-released refrigerant is secondarily compressed by the high-pressure compressing portion. The secondarily compressed refrigerant is secondarily released in heat by the secondary heat-releasing path to thereby obtain a low-temperature and high-pressure refrigerant. The low-temperature and high-pressure refrigerant is decompressed and expanded by an expansion valve and passes through the cooler to absorb the heat in a room air, and then returns to the low-pressure compressing portion of the compressor. In this system, the refrigerant temperature during the heat-releasing procedure can be kept low.

Abstract: A heat exchanger according to the present invention includes a pair of header tanks 10a and 10b and a plurality of heat exchanging tubes 30 disposed between the header tanks and arranged in parallel. The header tank 10 and 10b is provided with partitioning walls 15 integrally formed to the header tank along the longitudinal direction. The inside space of the header tank is divided by the partitioning walls 15 into tank partions 11 to 014. Refrigerant turning communication apertures 17 are formed in the predetermined partitioning wall 15. The refrigerant passages 35 of the heat exchanging tube 30 are grouped so as to correspond to each tank portion of the header tank 10a and 10b to thereby form a plurality of passes P1 to P4. The refrigerant introduced into the first tank portion 11 of one of the header tanks 10a passes through each passes P1 to P4 in this order from the rear side toward the front side, and then introduced into the fourth tank portion 14 of the other of the header tanks 10b.

Abstract: In the present invention, a header tank 10 includes a header tank main body 11 and a cover plate 20. The header tank main body 11 is provided with a refrigerant inlet passage 12a and a refrigerant outlet passage 12b arranged in parallel, connecting apertures 14a and 14b formed on a tube connecting side 13 and communicating with the passages 12a and 12b, and a communicating aperture communicating with the passages 12a and 12b. The cover plate 20 has insertion apertures 24a and 24b corresponding to the connecting apertures 14a and 14b. The tubes 1a and 1b, the cover plate 20 and the header tank main body 11 are integrally joined in a state in which each end of the tube 1a and 1b is inserted into the insertion aperture 24a and 24b of the cover plate 20 disposed on the tube connecting side 13a of the header tank main body 11 and connected to the connecting apertures 14a and 14b of the header tank main body 11.