Patent ID: 9039397
Filing Date: 2015-05-26
Classification: F04C

Abstract:
1. A rotor for an oil pump, comprising: an inner rotor part having a plurality of inner rotor teeth, each of which has a plurality of ellipses or circles; and an outer rotor part that is disposed on an outside of the inner rotor part, the outer rotor part having a plurality of outer rotor teeth, and has one outer rotor tooth more than the inner rotor part, wherein, in an inner rotor tooth of the plurality of inner rotor teeth, a tooth top and a tooth root of a drive-side half-tooth region extending from the tooth top to the tooth root and a tooth top and a tooth root of a non-drive-side half-tooth region extending from the tooth top to the tooth root are each configured by a different ellipse or a circle, and a circumferential axis along a circumferential direction of the ellipse or circle configuring the tooth top is longer in the non-drive-side half-tooth region than in the drive-side half-tooth region, and wherein a top of the tooth of the inner rotor part is in a shape of an ellipse, a root of the tooth in the non-drive-side half-tooth region of the inner rotor part is in a shape of an ellipse, and the teeth of the outer rotor part are each formed of an envelope that is formed when the teeth of the inner rotor part rotate.