Patent ID: 7121240
Filing Date: 2006-10-17
Classification: F01L

Abstract:
1. An apparatus comprising: a valve controller for adjusting a valve characteristic of an internal combustion engine utilizing rotational torque of a motor, the valve controller comprising: a control circuit generating a control signal; a plurality of rotational position sensors detecting rotational position of the motor and generating respective rotational position signals; and a driving circuit for driving the motor based on the control signal and the rotational position signals, the driving circuit generating a rotation number signal which represents actual rotation of the motor based on the rotational position signals, the driving circuit transmitting the rotation number signal to the control circuit; wherein the driving circuit receives the rotational position signals which have a voltage that is varied according to rotational position of the motor, and wherein the driving circuit changes voltage of the rotation number signal between high voltage and low voltage at the time of every edge of the rotational position signals.