INTERNAL GEAR PUMP

PROBLEM TO BE SOLVED: To provide an internal gear pump wherein complexity is reduced on the control of the clearance of an outer rotor and an inner rotor being a rotary body against a housing being a fixed body. SOLUTION: This internal gear pump has a first port and a second port opening in a plurality of pump rooms, a side plate movably arranged in the shaft direction between the housing, the outer rotor and the inner rotor and having a first pressure introducing hole arranged so as to penetrate in the shaft direction through a position corresponding to the first port and a second pressure introducing hole arranged so as to penetrate in the shaft direction through a position corresponding to the second port, a first seal member arranged on the opposite side in the shaft direction to both rotors of the side plate and defining a first area including the first pressure introducing hole from the other area, and a second seal member arranged on the opposite side in the shaft direction to both rotors of the side plate and defining a second area including the second pressure introducing hole from the other area. COPYRIGHT: (C)2007,JPO&INPIT