AIRTAC solenoid valves are divided into three categories in principle:

AIRTAC solenoid valves are divided into three categories in principle

1) Direct-acting solenoid valve: Principle: When energized, the solenoid coil generates electromagnetic force to lift the closing member from the valve seat, and the valve opens;when the power is turned off, the electromagnetic force disappears, and the spring presses the closing member against the valve seat. , the valve is closed. Features: It can work normally under vacuum, negative pressure and zero pressure, but the diameter generally does not exceed 25mm.
2) Step-by-step direct-acting solenoid valve: Principle: It is a principle that combines direct-acting and pilot-operated. When there is no pressure difference between the inlet and outlet, after power is turned on, the electromagnetic force directly connects the pilot small valve and the main valve. The valve closing parts are lifted upward in turn, and the valve opens. When the inlet and outlet reach the starting pressure difference, after power is turned on, the electromagnetic force pilots the small valve. The pressure in the lower chamber of the main valve increases and the pressure in the upper chamber decreases, thereby using the pressure difference to push the main valve upward;when the power is turned off, the pilot valve uses the spring Force or medium pressure pushes the closing member to move downward to close the valve. Features: It can operate safely under zero pressure difference or vacuum or high pressure, but the power is large and it must be installed horizontally. 3) Pilot solenoid valve: Principle: When energized, the electromagnetic force opens the pilot hole, and the pressure in the upper chamber drops rapidly, forming an upper, lower, and higher pressure difference around the closing member. The fluid pressure pushes the closing member to move upward, and the valve opens;When the valve is powered on, the spring force closes the pilot hole, and the inlet pressure quickly passes through the bypass hole and forms a pressure difference between the lower and upper parts around the valve closing part. The fluid pressure pushes the closing part downward to close the valve. Features: The upper limit of the fluid pressure range is relatively high and can be installed arbitrarily (customization is required) but the fluid pressure difference condition must be met. 2. Solenoid valves are divided into six subcategories based on differences in valve structure, materials and principles: direct-acting diaphragm structure, step-by-step direct-acting diaphragm structure, pilot diaphragm structure, direct-acting piston structure, Step-by-step direct-acting piston structure and pilot piston structure.