Patent ID: 7290995
Filing Date: 2007-11-06
Classification: F04C,Y10T

Abstract:
1. A tandem type trochoid pump comprising: a housing body of a cylindrical shape comprising an opening end portion and a bottom end portion; a pump cover sealing the opening end portion; a first trochoid pump disposed adjacent to the bottom end portion, the first trochoid pump comprising a first inner rotor and a first outer rotor; a second trochoid pump disposed adjacent to the opening end portion in tandem with the first trochoid pump, a phase of the second trochoid pump being different from a phase of the first trochoid pump, the second trochoid pump comprising a second inner rotor and a second outer rotor; a drive shaft comprising a non-circular end portion, the drive shaft receiving a rotational force at the other end portion thereof; a spacer disposed between the first and second trochoid pumps in the housing body, the drive shaft rotatably penetrating the spacer; a first fixing portion for fixing the first inner rotor to the drive shaft in a rotational direction of the drive shaft, the first fixing portion being constructed by the non-circular end portion and a non-circular hole which is formed at an inner circumference of the first inner rotor and engageable with the non-circular portion; and a second fixing portion for fixing the second inner rotor to the drive shaft in the rotational direction of the drive shaft, the second fixing portion being constructed by a through hole which is formed at a second-inner-rotor position of the drive shaft and which extends in a diametrical direction of the drive shaft, a pin which is inserted in the through hole, and a pin groove which is formed on the second inner rotor and which is engaged with the pin.