The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Nov. 12, 2013
Filed:
Jan. 03, 2012
Hisashi Ono, Okazaki, JP;
Koji Nunami, Anjo, JP;
Hisashi Ono, Okazaki, JP;
Koji Nunami, Anjo, JP;
Aisin Seiki Kabushiki Kaisha, Kariya-shi, Aichi, JP;
Abstract
An oil pump rotor includes an inner rotor having (n) external teeth, an outer rotor having (n+1) internal teeth, and a casing forming a suction port and a discharge port for drawing/discharging fluid. In operation, fluid is drawn/discharged according to volume changes of cells formed between tooth faces. A tooth profile based on a mathematical curve has a tooth addendum circle Awith a radius Rand a tooth root curve Awith a radius R, a circle Dhas a radius Rsatisfying Formula (1), and a circle Dhas a radius Rsatisfying both Formulas (2) and (3):R>R>R  Formula (1)R>R>R  Formula (2)R≧R  Formula (3)A tooth profile of the external teeth includes a modification either, in a radially outer direction, on the outer side of the circle Dor, in a radially inner direction, on the inner side of the circle D