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, 1993
Filed:
Feb. 18, 1992
Hidetoshi Fujiwara, Aichi, JP;
Mitsunori Naruse, Okazaki, JP;
Toyoda Koki Kabushiki Kaisha, Kariya, JP;
Abstract
An improved tandem pump operates satisfactorily even at low temperatures. The pump has a pump housing, a first rotor, plural first vanes held by the first rotor, a second rotor, and plural second vanes held by the second rotor. A first cam ring, an intermediate side plate, and a second cam ring are disposed side by side to constitute first and second pump chambers in the housing. The side plate is split into plural parts. Oil delivered by rotation of the first rotor is forced into a pressure chamber formed between the plural parts of the intermediate side plate. The portion of the inner end surface of each first vane which receives pressure is made smaller in area than the portion of the inner end surface of each second vane which receives pressure.