Structural principle of pilot operated solenoid valve（1）

The main valve part is usually composed of a main valve body, a main valve core, springs, seals, etc. The main valve body is the outer shell of the entire main valve, which contains control holes and fluid channels inside; The main valve core is the main control component, which moves according to external signals to change the state of the control hole; The spring is used to balance the force of the main valve core, ensuring that it is in a closed state when not subjected to external forces; Seals are used to ensure the sealing performance of the main valve.

The pilot valve part is usually composed of a pilot valve body, a pilot valve core, an electromagnetic coil, etc. The pilot valve body is the outer shell of the entire pilot valve, which contains control holes and fluid channels inside; The pilot valve core is the main control component, which moves according to external signals to change the state of the control hole; Electromagnetic coils are used to provide control signals, allowing the pilot spool to move according to the magnitude of the signal.

Pilot operated solenoid valve, when powered on, relies on electromagnetic force to lift the valve stem and open the pilot valve port. At this time, the upper chamber of the solenoid valve releases pressure through the pilot hole, forming a high and low pressure difference around the main valve core. Under the action of the pressure difference, the fluid pressure drives the main valve core to move upwards and open the main valve port; When power is cut off, under the action of spring force and main valve core gravity, the valve stem resets, the pilot hole closes, the main valve core moves downward, and the main valve port closes; The pressure in the upper chamber of the solenoid valve increases, and the fluid pressure is pressurized towards the main valve core, resulting in better sealing.