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:
May. 28, 2013
Filed:
Feb. 17, 2009
Naoki Kokubo, Hiratsuka, JP;
Yoshiyuki Kobayashi, Atsugi, JP;
Masahiko Watanabe, Yokohama, JP;
Takahumi Oowada, Hitachinaka, JP;
Naoki Kokubo, Hiratsuka, JP;
Yoshiyuki Kobayashi, Atsugi, JP;
Masahiko Watanabe, Yokohama, JP;
Takahumi Oowada, Hitachinaka, JP;
Hitachi, Ltd., Tokyo, JP;
Abstract
A valve timing control apparatus includes a phase varying mechanism arranged to vary a relative rotational phase of a cam shaft with respect to a crank shaft; a driving mechanism arranged to provide a driving force to the phase varying mechanism by energization; a control mechanism configured to control a current applied to the driving mechanism; and a phase angle sensing mechanism arranged to sense the relative rotational phase of the cam shaft with respect to the crank shaft, and to have a detection period longer than a control period of the control mechanism in accordance with an engine operating state. The control mechanism is configured to repeat increasing and decreasing of the current applied to the driving mechanism when the phase varying mechanism continuously varies the relative rotational phase of the cam shaft with respect to the crank shaft by a predetermined angle or more.