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. 25, 2004
Filed:
Mar. 08, 2002
Toshihiro Takahara, Kariya, JP;
Yoshihiko Doi, Kariya, JP;
Other;
Abstract
An oil pump for an internal combustion engine is provided with an intake port and a discharge port, each formed in a pump housing. The oil pump has a power pump serving as a first main pump and an electric pump serving as a second auxiliary pump, both of which may be contained in a same pump housing. The power pump is rotated by a driving force of a crankshaft, and the electric pump is rotated by the driving force of an electric motor. This makes it possible to reduce the maximum capacity of the power pump serving as the main pump. In a vehicle operating range where the oil discharging pressure generated by the power pump becomes insufficient, the electric pump serving as the auxiliary pump is operated together with the power pump such that appropriate oil discharging pressure or appropriate oil discharging quantity can be achieved. The electric pump may also be allowed to operate for a period of time after shutting off of the engine.