PURPOSE: To reduce the starting-up torque on starting and the abnormal rise of pressure in compressing liquid by urging an eccentric pin fixed on a slider in the direction to increase its radius of revolution by means of an elastic member and allowing a compression chamber and a pressurizing chamber to communicate through a pressure introducing hole.
CONSTITUTION: When a rotary shaft 7 revolves, a movable scroll member 16 is revolved by the eccentric pin 11 integrally fixed on a slider 9, and the radius of revolution of the movable scroll member 16 increases, as the centrifugal force of the scroll member overwhelms the elastic force of a pressing spring 12, and the sealing performance at the contact parts of both scroll parts 16c and 22b is improved, and the pressure in a compression chamber 28 increases gradually. Thus, the starting-up torque on starting can be reduced by applying the pressure in the compression chamber 28 to a pressurizing chamber 14 in the direction to increase the radius of revolution of the eccentric pin 11. As the pressure introducing holes 15 and 26 which allow the pressurizing chamber 14 and the compression chamber 28 to communicate with each other are formed narrow to a fixed length, the abnormal rise of the pressure in the compression chamber 28 is prevented by the throttle action, when liquid is compressed.
HATSUTORI MITSUHIRO
OONO HIROMITSU
