Abstract: In order to reduce the amount of refrigerant circulating within a variable displacement compressor to thereby improve compression efficiency, a control valve is configured to comprise a ball valve for controlling the flow rate of refrigerant flowing from a discharge chamber to a crankcase, a spool valve for controlling the flow rate of refrigerant flowing from the crankcase to a suction chamber, a diaphragm for sensing suction pressure, and a solenoid for setting the suction pressure, wherein the spool valve starts flow rate control after the ball valve is fully closed or nearly fully closed, and the ball valve starts flow rate control after the valve lift of the spool valve is minimized or nearly minimized.

Abstract: A supercritical refrigeration cycle using CO2 for a refrigerant and having a pressure exceeding the critical point of the refrigerant on a high-pressure side, wherein: the supercritical refrigeration cycle allows the refrigerant and a part of a lubricating oil to circulate, and the lubricating oil used does not contain an epoxy-based oxygen scavenger or an additive which is thermally decomposed on the high-pressure side and its decomposed components make a chemical reaction to produce a compound having low solubility to the refrigerant so as to prevent a deposit from being produced at a portion where the refrigerant is decompressed.

Abstract: The outer diameter &PHgr;d1 of a top face-side end portion 35 of pistons 7 is made slightly smaller than the outer diameter &PHgr;d0 of a hollow cylindrical portion 36 of the pistons 7 other than the top face-side end portion 35. Thus, the tilt load of a top face-side portion of the piston 7 is divided and distributed, and at the same time, lubricating oil is held at the top face-side end portion 35 of the piston 7.

Abstract: An expansion device capable of preventing an abnormal increase in the high-pressure in a freezing cycle and having, as an integrated unit thereof, a mechanism capable of quickly responding to an abnormal increase in the high-pressure and the low-pressure is provided. A means for displacement (bellows) 28 which becomes displaced in correspondence to the high-pressure is linked to a valve element 24 of a restrictor valve mechanism 32 to displace a rod 34 provided with a safety valve mechanism 33.

Abstract: The freezing cycle according to the present invention is provided with a first means for safety that leaks the high pressure to the low-pressure side when the high pressure reaches a level equal to or higher than a first specific pressure, a second means for safety that releases the high pressure into the atmosphere when the high pressure reaches a level equal to or higher than a second specific pressure, a third means for safety that stops the operation of the compressor when the high pressure reaches a level equal to or lower than a third specific pressure and a fourth means for safety that releases the low-pressure into the atmosphere when the low-pressure reaches a level equal to or higher than a specific pressure. In addition, a splash-preventing film is formed over specific areas of devices constituting the freezing cycle.

Abstract: There is provided a vane compressor which prevents leakage of refrigerant gas by decreasing the number of airtight interfaces between component parts and prevents seizure from occurring between its rotor and its side block without surface treatment of the side block. The vane compressor has a cam ring. The rotor is rotatably received in the cam ring. A first head is secured to one end face of the cam ring. A second head is secured to another end face of the cam ring in a manner such that the second head closes an opening of the another end face of the cam ring and one end face of the rotor can be brought into contact with the second head. The side block is received in the first head in a manner such that it closes an opening of the one end face of the cam ring and another end face of the rotor can be brought into contact with the side block.

Abstract: A vane compressor has at least one of a front-side member and a rear-side member thereof formed with a suction chamber opening toward a cam ring, which has a substantially arcuate or annular shape and extends around a drive shaft. The cam ring has one end face formed with a refrigerant inlet port for supplying a low-pressure refrigerant into compression chambers formed between vanes. Alternatively, a front head is arranged on one end face of the cam ring. A shell encloses another end and an outer peripheral surface of the cam ring and holds a movable plate in a state opposed to the other end face of the cam ring such that the movable plate can be moved along a central axis of the drive shaft. An inside of the shell and the movable plate defines a high-pressure chamber therein. Each adjacent pair of the vanes, the front head, and the movable plate defines a compression chamber therein.

Abstract: A vane compressor has at least one of a front-side member and a rear-side member thereof formed with a suction chamber opening toward a cam ring, which has a substantially arcuate or annular shape and extends around a drive shaft. The cam ring has one end face formed with a refrigerant inlet port for supplying a low-pressure refrigerant into compression chambers formed between vanes. Alternatively, a front head is arranged on one end face of the cam ring. A shell encloses another end and an outer peripheral surface of the cam ring and holds a movable plate in a state opposed to the other end face of the cam ring such that the movable plate can be moved along a central axis of the drive shaft. An inside of the shell and the movable plate defines a high-pressure chamber therein. Each adjacent pair of the vanes, the front head, and the movable plate defines a compression chamber therein.

Abstract: A a cartridge type delivery valve assembly in which a valve seat surface and a valve are integrated in order to assure good seating characteristics in the delivery valve. The delivery valve assembly is formed by fixing together a valve holder provided with delivery holes, a roll valve that is mounted along the internal surface of the valve holder to freely open and close the delivery holes and a valve stopper that fixes the roll valve onto the valve holder and regulates the lift quantity of the roll valve, in an integrated manner using coupling members and the delivery valve assembly thus achieved is mounted in a valve insertion space.