Patent ID: 6417642
Filing Date: 2002-07-09
Classification: B60Q

Abstract:
A motor-controlling circuit, for an optical-axis-adjusting unit of a vehicle illuminating device, having a direct current motor as a drive source for adjusting the optical axis and a position detecting portion thereof, which carries out feedback control so that an error value between the present position information of the motor, which is obtained by the position detecting portion, and a target value of position control becomes zero, comprising:a proportional calculation portion for calculating said error; an integration calculation portion for integrating the errors calculated by said proportional calculation portion; a differential calculation portion for calculating a first-order derivative per time with respect to the position information from said position detecting portion; a PID calculation processing portion for calculating an amount of control by adding respective outputs of said proportional calculation portion, said integration calculation portion, and said differential calculation portion, after said respective outputs have been multiplied by respective weighting coefficients; and a pulse width modulating control portion for generating a control signal having a duty cycle that is varied in response to the amount of control from said PID calculation processing portion, and for carrying out drive control of the direct current motor on the basis of said control signal.