An electromagnetic valve, also known as a gas solenoid valve, air valve, or pneumatic solenoid valve, is a device that controls the opening or closing of a gas path by electromagnetic force.
How it works:
When the electromagnetic coil is energized, the electromagnetic force is generated, which makes the spool move, thus opening or closing the gas path.
When the electromagnetic coil is powered off, the electromagnetic force disappears, the spool returns to its original position, and the gas path is closed or opened.