Construction machinery excavator parts TM61602 TM68602 electric proportional pressure reducing valve solenoid valve 12V

The working principle of the pneumatic solenoid valve is mainly through the electromagnetic force generated by the electromagnetic coil to promote the spool switching, so as to achieve the commutation of the air flow ‌. According to the different ways of driving the reversing valve in the electromagnetic control part, the pneumatic solenoid valve can be divided into direct-acting solenoid valve and pilot-operated solenoid valve. The direct-acting solenoid valve directly uses the electromagnetic force to drive the spool reversal, while the pilot-operated solenoid valve uses the pilot pressure output of the solenoid pilot valve to drive the spool reversal. ‌

A detailed description of how it works
‌ direct-acting solenoid valve ‌ : when the coil is energized, the static iron core generates electromagnetic force, the spool is moved upward by the electromagnetic force, the gasket is lifted, so that 1 and 2 are connected, 2 and 3 are disconnected, the valve is in the intake state, and the cylinder action can be controlled. When the power is off, the spool restores to its original state by the action of the spring force, that is, 1 and 2 are disconnected, 2 and 3 are connected, and the valve is in the exhaust state.

‌ pilot solenoid valve ‌ : When the power is on, the static iron core generates electromagnetic force to make the pilot valve operate, compressed air enters the valve pilot piston through the air path to make the piston start and open the channel. When the power is off, the pilot valve is reset under the action of the spring and returns to the original state.

The difference between different types of solenoid valves
‌ direct-acting solenoid valve ‌ : simple structure, the electromagnetic force directly acts on the spool, suitable for low pressure and high frequency operation scenarios. However, the disadvantage is that the electromagnetic force must be large, resulting in a large coil volume and high energy consumption.
‌ pilot operated solenoid valve ‌ : with air pressure auxiliary operation, suitable for high pressure and large diameter scenes. Its advantage is that it can work normally under high pressure, but the structure is complex and the price is high.
By understanding these working principles and characteristics, it is possible to better select the pneumatic solenoid valve suitable for specific application scenarios.