| 摘要 |
<p>PURPOSE:To obtain a transistor chopper apparatus with a limited loss by supplying current to the base of a transistor for controlling the rotation of a DC motor from an excitation coil of a solenoid switch. CONSTITUTION:When a forward/backward changeover switch 2 is closed at the forward position thereof and an acceleration pedal is depressed, a transistor T7 conducts and current flows through an exitation coil 3 of a forward solenoid switch by way of a transistor 8 to close a contact 3'. With further depressing of the acceleration pedal, the transistor TR8 is on or off controlled with the output from a signal generator circuit 6 according to the depressing level. When the transistor TR8 is off, current of an excitation coil 3 is fed to a base of the transistor TR9 for controlling the revolution of a DC motor 5. In the backward operation, likewise, the revolution of the motor 5 can be controlled. This eliminates the need for separator power for driving the base of the transistor TR9 thereby providing a transistor chopper appa ratus with a limited power loss.</p> |
