Patent ID: 7384251

Claim:
A trochoidal oil pump comprising: a rotor chamber which has an intake port and a discharge port; an outer rotor; and an inner rotor, wherein a tooth shape of the inner rotor is formed according to a trochoidal curve, a top part contact region and a root part contact region, which make contact in an engagement with the tooth shape of the inner rotor, are formed in a tooth top part and a tooth root part of the tooth shape of the outer rotor, a non-contact region, which is always in a state of non-contact region, which is always in a state of non-contact with the tooth shape of the inner rotor, is formed on a side edge of the tooth shape between the top part contact region and root part contact region of the tooth shape, and a region equivalent to the non-contact region is not formed on a side of the inner rotor side, wherein a plurality of inter-tooth spaces formed by the tooth shapes of the inner rotor and outer rotor comprise a maximum sealed space that is positioned in a region of a partition part between the intake port and discharge port, a plurality of inter-tooth spaces within a region of intake port, and a plurality of inter-tooth spaces within a region of the discharge port, and the plurality of inter-tooth spaces in said intake port and discharge port respectively communicate with each other via communicating parts formed by the non-contact region in the outer rotor.