Patent ID: 6887056
Filing Date: 2005-05-03
Classification: F04C

Abstract:
1. An oil pump rotor assembly comprising: an inner rotor having “n” external teeth; and an outer rotor having (n+1) internal teeth which are engageable with the external teeth, wherein the inner rotor and the outer rotor are formed such that the following equations are satisfied:  where øDi is the diameter of the base circle of the inner rotor, øAi is the diameter of the first circumscribed-rolling circle, øBi is the diameter of the first inscribed-rolling circle, øDo is the diameter of the base circle of the outer rotor, øAo is the diameter of the second circumscribed-rolling circle, øBo is the diameter of the second inscribed-rolling circle, and t (≠0) is gap between the tooth tip of the inner rotor and the tooth tip of the outer rotor.