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:
Feb. 28, 2006
Filed:
Jun. 17, 2002
Yoshihiro Majima, Inuyama, JP;
Jun Hasegawa, Kariya, JP;
Hisashi Iida, Kariya, JP;
Masaomi Inoue, Kariya, JP;
Hideyuki Maeji, Okazaki, JP;
Haruyuki Urushihata, Chiryu, JP;
Noriaki Iwase, Chiryu, JP;
Yoshihiro Majima, Inuyama, JP;
Jun Hasegawa, Kariya, JP;
Hisashi Iida, Kariya, JP;
Masaomi Inoue, Kariya, JP;
Hideyuki Maeji, Okazaki, JP;
Haruyuki Urushihata, Chiryu, JP;
Noriaki Iwase, Chiryu, JP;
DENSO Corporation, Kariya, JP;
Abstract
A control unit employed in a variable valve timing apparatus vibrates a control signal for controlling an oil-pressure control valve. If the vibration center of the duty value of the control signal for driving the oil-pressure control valve lies in a dead band, the vibration takes the duty value to the outside of the dead center temporarily. Thus, even if the center value of the control signal lies in the dead band, the valve timing of the oil-pressure control valve changes with variations in control signal. As a result, the width of the dead band appears small or to have a value of zero. Accordingly, the response characteristic of variations in valve timing to the variations in control signal is improved. The vibration of the control signal is also effective for detection of a width of the dead band.