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:
Aug. 14, 2012
Filed:
Jul. 15, 2010
Minoru Wada, Obu, JP;
Minoru Wada, Obu, JP;
Denso Corporation, Kariya, JP;
Abstract
An engine valve control device is applied to an engine valve control mechanism having a VVT (valve timing adjusting device), an OCV (control valve) that controls a flow of hydraulic oil supplied to the VVT, and an electromagnetic solenoid that controls an operation of the OCV according to a control duty (control command value). The engine valve control device calculates the control duty based on a holding duty, which occurs when an actual phase does not change but is held, and feedback correction values. The engine valve control device corrects the value of the holding duty in accordance with a steady-state deviation between the actual phase and a target phase to perform learning for storing and updating the holding duty value. If temperature of the hydraulic oil is low, the learning is prohibited even when the steady-state deviation is occurring.