Patent ID: 8870556
Filing Date: 2014-10-28
Classification: F04C

Abstract:
1. An oil pump comprising: a pump body; an inner rotor having outer teeth; and an outer rotor having inner teeth, wherein a maximum partition portion is formed between a trailing end side of an intake port and a leading end side of a discharge port in a rotor chamber of the pump body, a minimum partition portion is formed between a trailing end side of the discharge port and a leading end side of the intake port, in a cell constituted by the outer teeth of the inner rotor and the inner teeth of the outer rotor, an inner tooth of the outer rotor meshes so as to penetrate between the outer teeth of the inner rotor at the minimum partition portion, a total of three cells including a central cell positioned at a location of the maximum partition portion and two adjacent cells positioned in front of the central cell and behind the central cell in a rotation direction, are sealed by mutual contact of the outer teeth and the inner teeth, and on a minimum partition portion side, the outer teeth and the inner teeth are not brought close to a degree such that the outer teeth and the inner teeth can seal cells, and the cells communicate with each other.