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:
Oct. 09, 2012
Filed:
Jun. 20, 2008
Makoto Tomimatsu, Susono, JP;
Nobuhiko Koga, Aichi-gun, JP;
Makoto Tomimatsu, Susono, JP;
Nobuhiko Koga, Aichi-gun, JP;
Toyota Jidosha Kabushiki Kaisha, Toyota-shi, JP;
Abstract
The oil pressure for a hydraulic actuator () of a variable valve train () is controlled in accordance with a duty value of a control signal for a hydraulic control valve (). When predetermined inching control execution conditions are established, inching control in which the duty value is varied in a pulsed manner between a retention duty value, which retains an operation of the hydraulic actuator, and a forced drive duty value, which forcibly drives the hydraulic actuator, is exercised instead of duty value feedback control in which the duty value is calculated in accordance with the deviation between an actual valve opening characteristic and a target valve opening characteristic. If the oil temperature is lower than a predetermined temperature, inching control is exercised to ensure that the first pulse width generated after the start of inching control is wider than normal.