| 摘要 |
PURPOSE:To prevent the occurrence of vibration consistant with the generation of counter electromotive current, by providing a circuit to get the counter electromotive current generated in turning OFF switching elements to be consumed. CONSTITUTION:In stepping drive, e.g. after transistors T1 and T4 are turned OFF while transistors T2 and T3 come to be turned ON, the counter electromotive current generated in a phase winding phi1 flows: a diode D3 a Zener diode ZD1 a capacitor Co a Zener diode ZD2 a diode D2 a phase winding phi1 as shown in dotted line in the figure. In this way, the counter electromotive current is consumed by resistance elements of Zener diodes ZD1 and ZD2, a part of which is accumulated in a capacitor Co. The electric charge stored in the capacitor Co is discharged when transistors T2 and T3 are turned ON by the next pulse and becomes a part of exciting current. |
