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:
Jun. 06, 2017
Filed:
Feb. 23, 2015
Hitachi Automotive Systems, Ltd., Hitachinaka-shi, Ibaraki, JP;
Hideaki Ohnishi, Atsugi, JP;
Yasushi Watanabe, Kanagawa, JP;
HITACHI AUTOMATIVE SYSTEMS, LTD., Hitachinaka-Shi, JP;
Abstract
A variable displacement pump includes a variable mechanism configured to change a volume-variation rate of each pump chamber by movement of a movable member; a biasing mechanism provided to bias the movable member in a direction that increases the volume-variation rate; at least one reduction-side control oil chamber to which oil is supplied from a discharge portion such that the reduction-side control oil chamber applies force to the movable member in a direction that reduces the volume-variation rate; at least one increase-side control oil chamber to which oil is supplied from the discharge portion such that the increase-side control oil chamber applies force to the movable member in the direction that increases the volume-variation rate; and a control mechanism configured to control a oil quantity which is supplied to each control oil chamber. The total number of the control oil chambers is three or more.