摘要 |
A stepper motor driving apparatus, includes a stepper motor; a driven member interlocked with a rotation of a rotor of the stepper motor, a stopper stopping the driven member in a zero position, a controller controlling the excitation state of an excitation coil of the stepper motor, an induced voltage waveform detector detecting an induced voltage waveform generated on the basis of change of magnetic flux in accordance with the rotation of the rotor, and a zero position detector detecting whether the driven member is stopped in the zero position. The zero position detector includes a comparator which compares a time T 2 in which each induced voltage waveform exceeds a predetermined threshold value with a predetermined contact determining reference time Tref, and a determinant which determines whether the driven member is stopped in the zero position by the stopper based on a result of the comparison by the comparator.
|