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:
May. 20, 2008
Filed:
Jul. 21, 2005
Yasuhito Nakakuki, Kanagawa, JP;
Toshimitsu Sakaki, Kanagawa, JP;
Yasuhito Nakakuki, Kanagawa, JP;
Toshimitsu Sakaki, Kanagawa, JP;
Hitachi, Ltd., Tokyo, JP;
Abstract
An oil pump is provided which includes a cam ring made of a material having a first line expansion coefficient, a pump element rotatably disposed in the cam ring and smaller in an axial length than the cam ring, a first housing member disposed on one of axially opposite sides of the cam ring and made of a material having a second line expansion coefficient larger than the first line expansion coefficient, and a second housing member disposed on the other of the axially opposite sides of the cam ring and made of a material having a third line expansion coefficient than the first line expansion coefficient.