Patent ID: 7153110

Claim:
A rotational pump having variable volume flow, the pump comprising: a pump housing having a suction connection and a pressure connection; an outer rotor having inner toothing, said outer rotor rotatably disposed inside said housing; an inner rotor having outer toothing, said inner rotor eccentrically disposed in said outer rotor; a drive shaft disposed in said pump housing, said drive shaft extending parallel to an axis of said outer rotor, said drive shaft cooperating with said inner rotor; a rotatable adjusting ring, within which said outer rotor is eccentrically and rotatably disposed, said adjusting ring disposed coaxially to said drive shaft; and a slider disposed, as viewed in a turning direction, between said pressure connection and said suction connection, said slider communicating with said adjusting ring to vary a size of at least one of said pressure connection and said suction connection for changing the volume flow in said pump housing, wherein said pressure connection and said suction connection define at least one groove having a shape of a partial circle, with said slider being displaceably disposed in said groove.