After reading this second, understand the working principle of the solenoid valve!
There are many types of solenoid valves. Different solenoid valves play a role in different positions of the control system. The most commonly used ones are check valves, safety valves, directional control valves, speed control valves, etc.
So first of all talk about the working principle of the solenoid valve:
There is a closed cavity in the solenoid valve with through holes at different positions. Each hole is connected to a different oil pipe. In the middle of the cavity is a piston. There are two electromagnets on both sides. Which side of the magnet coil will be attracted to the valve body when it is energized. On the other hand, by controlling the movement of the valve body to open or close the different oil discharge holes, and the oil inlet is normally open, the hydraulic oil will enter the different oil discharge pipes, and then the piston of the cylinder is pushed by the oil pressure. Drive the piston rod, and the piston rod drives the mechanical device. In this way, the mechanical movement is controlled by controlling the current on and off of the electromagnet.