Patent ID: 8206128
Filing Date: 2012-06-26
Classification: F01C,F04C

Abstract:
1. A refrigeration cycle system provided with a rotary compressor including a sealed case, an electric motor disposed in the sealed case and a compression mechanism disposed in the sealed case and connected to the electric motor, wherein the compression mechanism is provided with a first compression section and a second compression section, each compression section having a cylinder and a cylinder chamber in which rollers are held to be eccentrically rotatable, respectively, and also provided with blades disposed in the first and the second cylinders each blade having a leading end urged by a spring member so as to abut against a curved surface of the roller and serving to separate the cylinder chamber into two sections along a rotating direction of the roller, one of the first and the second compression sections is provided with a capacity regulating mechanism including a switching member which serves to switch and guide low-pressure refrigerant or high pressure refrigerant of the refrigeration cycle to a back-pressure chamber formed to a back surface side of the blade, to guide the high-pressure refrigerant into the cylinder chamber when the low-pressure refrigerant is guided into the back-pressure chamber and to guide the low-pressure refrigerant into the cylinder chamber when the high-pressure refrigerant is guided into the back-pressure chamber, and wherein the switching member is switched so as to guide the high-pressure refrigerant into the back-pressure chamber of one of the compression sections in a high load state and guide the low-pressure refrigerant into the cylinder chamber so as to perform a normal operation by pushing the blade against the roller by pressure difference between pressure of the high-pressure refrigerant guided into the back-pressure chamber and pressure of the low-pressure refrigerant guided into the cylinder chamber, and on the other hand, the switching member is switched so as to guide the low-pressure refrigerant into the back-pressure chamber of one of the compression sections in a low load state and guide the high-pressure refrigerant into the cylinder chamber so as to perform an uncompressed operation by separating the blade from the roller by pressure difference between pressure of the low-pressure refrigerant guided into the back-pressure chamber and pressure of the high-pressure refrigerant guided into the cylinder chamber; and wherein the one compression section with the capacity regulating mechanism includes the back-pressure chamber at the back surface side of the blade, which is opened and closed by a pressure difference between a pressure in the back-pressure chamber and a pressure in an inner space of the sealed case acting on a valve body, the valve body is closed to seal the back-pressure chamber upon introduction of the low pressure refrigerant to the back-pressure chamber through a pressure introduction hole communicated with the back-pressure chamber and formed for introducing the low pressure refrigerant, and the valve body is opened upon introduction of the high pressure refrigerant to establish a communication between the back-pressure chamber and the inner space of the sealed case through a communication hole formed in one of the compression sections, and the communication introduces a lubricating oil from the inner space of the sealed case into the back pressure chamber.