1. Functions of Kobelco excavator controller
① Setting of engine speed. The device sends a voltage output signal corresponding to the position of the throttle control knob to make the governor motor rotate a certain angle. The potentiometer feeds back the rotation angle signal to the engine throttle controller, and has been monitoring the operation of the governor motor.
② Use the No. 2 throttle signal from the hydraulic pump controller for control. The engine throttle controller uses the No. 2 throttle control signal from the hydraulic pump controller to control the engine speed.
③ Use hydraulic pump controller automatic deceleration signal to automatically decelerate. When the hydraulic pump controller detects that all the joysticks are in the neutral position, it will send an automatic deceleration signal to the engine door controller. When the engine door controller receives this signal, it will reduce the engine speed.
④ Automatic heating. After the engine is started, if the engine water temperature is low, the monitor will send a warm-up signal to the engine throttle controller, and the controller will output a signal to the governor motor to rotate the motor and fuel injection pump control lever, and the engine speed
High, make the engine water temperature rise.
⑤ Use the start switch signal to stop the engine. When the start switch is turned to the off position, the engine throttle controller drives the speed regulating motor to turn the fuel injection pump control lever to the non-injection position, and the engine stops.
⑥ Automatic diagnosis. The 3 LED displays (red, green, red) are on or off, indicating whether the excavator is working normally, or indicating the fault location when an abnormal situation occurs.
Second, the internal structure of the controller
1. Input circuit
The controller receives the throttle control knob (throttle signal), monitoring (warm-up signal), speed-regulating motor potentiometer (potentiometer signal), start switch (start or stop signal), hydraulic pump controller (throttle signal No. 2 or After the signal from the automatic deceleration signal), input it into the microcomputer. Here, the noise in the signal is removed and the waveform of the signal is corrected. At the same time, it also provides close to 5V power supply for the governor motor potentiometer and the throttle control button.
2. Microcomputer
The rotation angle of the governor motor is determined by the magnitude of the input signal current. After the input signal current is processed by the computer, it drives the speed regulating motor.
3. Throttle control knob
The device is installed under the monitor panel, and the potentiometer is installed under the knob. When the knob is turned, the shaft of the potentiometer is rotated. This rotation changes the resistance of the variable resistor in the potentiometer and sends the desired signal to the engine controller. There are 10 operating positions on the throttle control knob.
4. Speed governor motor
The governor motor is composed of potentiometers, gears, and motors. The drive signal sent by the engine throttle controller controls the rotation of the electric motor, which is driven by the connecting rod of the speed regulating motor. The adjustment dimensions of the governor control rod of the engine fuel injection pump and the governor motor connecting rod are shown in Figure 5.4. A stepping motor is used as a motor. The rotation of the motor is transmitted to the potentiometer through a gear, and the potentiometer supervises the operation of the motor through a feedback signal.
Home position angle (stop bolt position)
1—lock nut; 2—fork; 3—regulator actuator; 4—spring assembly; 5—engine governor; 6—potentiometer Figure 54: governor motor connection
