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. 15, 2016
Filed:
Nov. 06, 2013
Hitachi Automotive Systems, Ltd., Hitachinaka-shi, Ibaraki, JP;
HITACHI AUTOMOTIVE SYSTEMS, LTD., Hitachinaka-Shi, JP;
Abstract
A variable displacement oil pump includes: a switching mechanism arranged to switch a state in which the hydraulic fluid is introduced to the second control hydraulic chamber through a connection passage, and a state in which the hydraulic fluid is discharged from the second control hydraulic chamber through the connection passage; and a control mechanism arranged to be actuated before the eccentric amount of the cam ring becomes minimum, and arranged to vary an opening area of the connection passage as the discharge pressure is increased, and to vary an opening area of a discharge passage arranged to discharge the hydraulic fluid within the second control hydraulic chamber, in a direction opposite to a direction of a variation of the opening area of the introduction passage.