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:
Jul. 20, 2010
Filed:
Aug. 08, 2008
Kazuhiko Abe, Kawasaki, JP;
Youichi Oshimi, Machida, JP;
Kazuhiko Abe, Kawasaki, JP;
Youichi Oshimi, Machida, JP;
Nissan Motor Co., Ltd., Yokohama-shi, Kanagawa, JP;
Abstract
A variable valve controller for internal combustion engines and methods for operating the same. In the variable valve controller, and engine control unit (ECM) calculates a target value of a valve lift (VEL) for an intake valve and transmits it to a controller with a second control unit (VEL-C/U). The VEL-C/U controls the VEL on the basis of the VEL target value, detects a VEL actual value, and transmits it to the ECM. The ECM calculates a target value of a valve timing (VTC), and controls the VTC. Also, the ECM controls a limit value for the VTC target value in accordance with the VEL actual value. Fail-safe control is performed when an error occurs in a communication unit or a sensor. To reliably perform the control in a period from occurrence of an error to detection of the error, the limit value is set with calculation by offsetting a limit basic value set in accordance with the VEL actual value, by a displacement of the VEL within a time necessary for detecting the error.