When the engine throttle control knob is rotated, the output voltage changes according to the position of the knob, and this signal is input to the engine throttle controller. The engine throttle controller connects the voltage of the knob with the motor position installed in the engine throttle control motor.
After comparing the voltage of the monitoring potentiometer, press the position specified by the knob to drive the motor. When the voltage of the knob is consistent with the voltage of the potentiometer, the throttle controller cuts off the current of the motor and stops it from rotating.
The engine control motor is equipped with a steel cable, and the end of this cable is connected to the adjusting rod of the engine fuel injection pump, so as the motor rotates, the adjusting rod always moves to achieve the purpose of controlling the engine speed.
1, engine control motor
Using a DC motor, a potentiometer for position monitoring is installed inside. When the engine throttle control motor has an abnormal load (when the control cable is aging or bent), the engine throttle controller limits the current of the throttle control motor to protect the system. Therefore, even if the engine throttle control knob is turned, the engine throttle control motor does not move. When the abnormal load is removed, turn off the start switch and restart, and turn the control knob of the engine throttle, everything can return to normal. When replacing or adjusting the engine control motor, it must be carried out in accordance with the adjustment method of the engine control device. If the adjustment is wrong, the performance of the equipment will not be able to play normally
2, Hitachi Excavator Engine Throttle Control Knob
A potentiometer is installed inside the engine throttle control knob. When the knob is turned, the resistance value of the potentiometer changes, and the output voltage (between 2/3 terminals) supplied to the throttle controller also changes accordingly.
