Patent ID: 8452519
Filing Date: 2013-05-28
Classification: F01L

Abstract:
1. A valve timing control apparatus for an internal combustion engine which is configured to control an opening timing or a closing timing of an intake valve or an exhaust valve, the valve timing control apparatus comprising: 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 a 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, wherein, during operation, the control mechanism repeats 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 at least a predetermined angle, and does not repeat increasing and decreasing of the current applied to the driving mechanism when the phase varying mechanism does not continuously vary the relative rotational phase of the cam shaft with respect to the crank shaft by at least the predetermined angle.