| 摘要 |
<p>PURPOSE:To prevent an electric motor vehicle from sliding down at its climbing time by increasing a current value to the prescribed current flow rate when a plugging occurs without switching a forward/reverse contactor. CONSTITUTION:The output from an accelerator 12 is supplied through a resistor R, a primary delay circuit of a capacitor C and a transistor TR1 to a current flow rate controlling circuit 13 of a chopper circuit 8. When a forward switch FSW is shifted to a reverse switch SW or vice versa, clock pulses are outputted from a flip-flop FF1 and an exclusive-OR circuit EX.OR and the voltage of a capacitor C3 is high level at this time. Accordingly, the output Q of a flip-flop FF2 becomes high level. A proportional controlling circuit C supplies the deviation between the output Q of the flip-flop FF2 and the output of a current flow rate detector A to a transistor TR2, thereby increasing the motor current.</p> |
