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:
Sep. 13, 2011
Filed:
Nov. 28, 2008
Minoru Wada, Obu, JP;
Yasuhiro Shikata, Kariya, JP;
Minoru Wada, Obu, JP;
Yasuhiro Shikata, Kariya, JP;
Denso Corporation, Kariya, Aichi-Pref., JP;
Abstract
A variable valve device modulates movement of a valve for an internal combustion engine by using hydraulic fluid pressure. The variable valve device is controlled by a control device via a control valve that modulates hydraulic fluid pressure supply to and discharge from the variable valve device. The control device offsets an operating amount of the control valve by an offset component that shifts the operating amount outside a dead band. The control device sets the offset component smaller as the hydraulic fluid temperature increases. The control device sets the offset component smaller when a controlling direction coincides with a biasing direction of a biasing member than that when the controlling direction opposes the biasing direction. Further, the control device cancels the offset component when actual valve movement is sufficiently close to target valve movement.