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. 14, 2008
Filed:
May. 03, 2007
Wataru Nagashima, Kariya, JP;
Wataru Nagashima, Kariya, JP;
DENSO CORPORATION, , JP;
Abstract
In a vane-type variable valve timing adjusting mechanism (VCT), an OCV target current is set to the holding current to hold an actual advance amount in close proximity to the target advance amount during the execution of the holding control. In the holding control, when the deviation between the actual and target advance amounts reaches beyond the holding control region (determination threshold value) and enters into the micro displacement control region, the micro displacement control (pulse-current application control) is started, and the pulse current is applied to the hydraulic control valve to use advantages of pulse current to drive the VCT in the direction of the target advance amount. Thus, when the actual advance amount comes back into close proximity to the target advance amount, the holding control is restarted, and the OCV target current is set to the holding current to hold the actual advance amount at the target advance amount.