摘要 |
A stepping motor control unit is capable of driving a stepping motor fast through feedback control. Slits bored in a disk fixed to a rotor of a stepping motor are located at positions that precede magnetically stable positions of the rotor in a direction of rotation of the rotor. Light passing through the slits is detected by an optical sensor, and a signal t is output thereby. The signal t is delayed by a predetermined time according to the rotating speed of the rotor and then transmitted to a control unit. The control unit receives a position detection signal earlier according to the rotating speed of the rotor. Therefore, the wait time required for switching phases can be shortened. Moreover, when the signal t is generated twice or more during a signal t detection time during which a signal t indicating a certain phase is detected, the second and subsequent signals t are ignored. Thus, incorrect detection can be avoided.
|