Excavator solenoid valve TM66001 24V 20Bar hydraulic pump proportional solenoid valve

The working principle of excavator solenoid valve
 

  The excavator mainly uses direct-acting solenoid valve, which has the advantages of convenient control, fast action, easy to achieve remote control, and can work normally under vacuum, negative pressure and zero pressure. The excavator solenoid valve has a closed chamber inside, the valve body is in the middle of the chamber, and the two ends of the valve body are configured with electromagnets according to the needs, or only one end is configured with electromagnets. Using the magnetic force generated by the principle of inductance, the control spool moves to achieve the oil circuit reversal, when the electromagnet coil is energized, the electromagnet will pull in the opposite direction, and push the spool to move in the direction of suction, thereby blocking or exposing different oil holes, and the oil will enter different pipelines according to the instructions. If the solenoid coil of the solenoid valve is burned out or cut off, it cannot generate magnetic force, and the valve core cannot be moved, and the excavator cannot perform related operations.

The solenoid valve on the hydraulic pump generally has two, one is the TVC solenoid valve, the other is the LS-EPC solenoid valve, the former is responsible for sensing the signal from the engine speed sensor, adjusting the engine power and the hydraulic pump power match, if damaged, either the engine is full of car, insufficient power, or the engine is difficult to start.
The latter is responsible for sensing the driver's operation and changes in the size of the external load, if damaged, it will cause weakness in digging, slow operation of the whole machine, poor micro-operation ability, and no high-speed gear. It should be noted that there is one TVC solenoid valve before and after the pump, and only one LS-EPC solenoid valve.
Hydraulic pump drive shaft can not withstand radial force and axial force, so it is not allowed to install belt wheels, gears, sprockets directly on the shaft end, usually with a coupling to connect the drive shaft and pump drive shaft.
If due to manufacturing reasons, the coaxial degree of the pump and the coupling exceeds the standard, and there is a deviation during assembly, the centrifugal force increases the deformation of the coupling with the increase of the pump speed, and the centrifugal force increases. Resulting in a vicious cycle, the result of vibration and noise, thus affecting the service life of the pump. In addition, there are other influencing factors such as coupling pin loosening and not timely tightening, rubber ring wear and not timely replacement.