| 摘要 |
PURPOSE:To prevent hunting by attaching an impedance element containing a nonlinear element to a speed control circuit adapted to control the supply of power to a bridge circuit including a motor to be controlled with a transistor in one side thereof CONSTITUTION:A bridge circuit is made up of a equivalent internal resistance and resistances 2-4 of a D.C. motor 1 to be controlled while an impedance element 12 comprising a resistance 13 and a Zener diode 14 are connected in parallel to a resistance 3 forming a side on the high resistance side of the bridge circuit. A comparator 6 compares a voltage at a point b with the reference voltage 5 to control a power supply controlling transistor 8 thereby regulating the revolution of the motor at a constant level. Therefore, when a voltage at the point b exceeds a Zener voltage with an increase in the load torque, current flows to reduce the revolution thereby effectively hunting in a high load torque. |
