STEP MOTOR FOR ELECTRONIC WATCH

摘要

PURPOSE:To eliminate the effect of variations in the time for saturating the minimum width part of a stator and stably run the motor backward by applying the control signal for magnetic erasing then starting backward running operation at the time of switching from forward running to backward operation and normally keeping applying the control signal during the backward running. CONSTITUTION:The output of an oscillation circuit 50 using crystal is frequency divided with a frequency dividing circuit 51 and the signals thereof are suitably inputted to a synthesizing circuit 52 they are waveform synthesized. The forward-backward running signals from a forward-backward running control circuit 55 are inputted to the synthesizing circuit 52 and the output thereof is inputted to a driving circuit 53. The motor is driven by the output of the driving circuit 53. At the reverse running of the rotor, the control signal being small to the extent of not causing the rotor to start moving is applied in the same polarity direction as that of the pulses being applied to the motor at its forward running, whereby the effect of the variations of the time for saturating the stator minimum width part of the integral stator is eliminated and the motor running backward stably is obtained voluminously.