| 摘要 |
PURPOSE:To permit the detection of the step-out of a motor with a simple circuit constitution, by a method wherein a voltage, corresponding to the current value of an exciting coil for the motor, is generated. CONSTITUTION:A 4-phase stepping motor 3, equipped with coils 3-1-3-4, is driven by a power source 2 through a driving transistor 8 and a current detecting resistor 9. A step-out detecting circuit 10 detects a voltage generated in the resistor 9 and outputs a step-out detecting signal. When the motor 3 has stepped out, the inductances of the coils 3-1-3-4 becomes extremely small as compared with the same during a constant speed rotation. Accordingly, the value of exciting current becomes large and a voltage, generated in the resistor 9 becomes high while the increased voltage may be detected by the step-out detecting circuits 10. |
