Stepping motor control method including varying the number of split

Abstract

A device for controlling the power supplied to windings of a stepping motor includes a pulse generator for splitting one step drive period of the motor into a plurality of sections, the number of sections and increasing or decreasing depending upon the drive frequency. The pulse generator, also sets the duty cycle of a pulse applied to the motor. The device also includes a stepping motor drive circuit for exciting each phase of the motor with a current determined by the duty cycle of pulse, and a duty changing device for changing the duty cycle for each of plural sections in one excitation phase of the stepping motor, wherein a current wave input into the motor can be maintained as a sinusoidal wave from low-speed rotation to high-speed rotation of the motor by changing the number of sections in excitation depending upon serial drive operations, thereby achieving motor control with less rotation inconsistencies and less noise.