Patent ID: 8096795
Filing Date: 2012-01-17
Classification: F04C

Abstract:
1. An oil pump rotor for use in an oil pump including an inner rotor having n external teeth wherein n is a natural number, an outer rotor having n+1 internal teeth meshing with the external teeth, and a casing forming a suction port for drawing a fluid and a discharge port for discharging the fluid, such that in association with meshing and co-rotation of the inner and outer rotors, the fluid is drawn/discharged to be conveyed according to volume changes of cells formed between teeth faces of the two rotors; said oil pump rotor having a modified tooth profile compared to an unmodified tooth profile, wherein, for said unmodified tooth profile formed of a mathematical curve and having an unmodified tooth addendum circle A wherein the unmodified tooth profile of the external teeth of the inner rotor is modified, in radially outer and inner directions, to establish a modified tooth profile of the external teeth of the inner rotor by being applied with correction factors outside the circle D wherein said mathematical curve comprises a cycloid curve represented by Formulas (4) through (8); and a modified external tooth profile of the inner rotor, in the case of said modified tooth profile on the outer side of the circle D where X axis: the straight line extending through the center of the inner rotor, Y axis: the straight line perpendicular to the X axis and extending through the center of the inner rotor, R R R θ θ (X (X where, R θ (X β where, R θ (X β