| 摘要 |
<p>PURPOSE:To reduce the rate of voltage change in a normal operation range and to reduce the size of a driver power source by downwardly shifting the voltage level of a smoothing circuit for smoothing the voltage of a rectifier when the voltage of a rectifier for rectifying the output voltage of a detecting winding is the set value or lower. CONSTITUTION:The output voltage of a generator detected by a detecting winding 4 is smoothed by a smoothing circuit after rectified by a rectifier 5. A transistor Q3 is turned ON during the zone that the retified voltage VS is the Zener voltage or lower of a Zener diode 10, and a pulsating voltage VC is shifted downwardly. A resistor Q1 is turned OFF and Q2 is turned ON during the zone that the shifted voltage VCL is the Zener voltage Vz or lower, and a field current if is supplied to the winding 3. In this manner, the rate of voltage change in the normal operation range can be reduced, and a drive power source can be reduced in size.</p> |
