Pilot operated solenoid directional valve

Pilot-operated electromagnetic reversing valve

The pilot-operated electromagnetic reversing valve first controls the air path by an electromagnet, generates pilot pressure, and then uses the pilot pressure to Push the main valve spool to change direction. Suitable for occasions with larger diameter. Pilot-operated dual-electrically controlled two-position four-way electromagnetic directional valve. It consists of pilot valve (Dl, D2) and main valve. The main valve includes a valve body 1 and a piston assembly 2. What is shown in the figure is that Dl and D2 are both in a power-off state. The moving iron cores 5 and 6 of the solenoid valve are in a closed state. When Dl is powered on and D2 is powered off, the moving iron core 5 is sucked up, and the compressed air from port P enters the f cavity of the valve through hole a (dashed line). And enter the hole 'from the surrounding lips of the sealing plug 4 (one-way valve), and enter. Wide cavity, push the piston assembly 2 downward, so that P and A can communicate, and B can communicate with T through the center hole h of the valve core (exhaust). When compressed air is output from port A, a part of the compressed air flows into hole g. One of the compressed air flows into the cavity c through the throttle hole d, causing the sealing plug 4 to move down to seal the exhaust hole b. The other compressed air enters the cavity f, acting on The upper end of piston assembly 2. At this time, even if D1 is powered off, the piston assembly 2 will not be in position, that is, the valve has a memory function. Pilot-operated double-electronically controlled two-position four-way electromagnetic reversing valve When the pilot valve D2 is powered on and Dl is powered off, the moving iron core 6 is sucked up, and the compressed air in the c cavity is discharged through the T1 port. At this time, the compressed air from P to A acts on the large and small pistons. Due to the area difference between the large and small pistons, an upward force is generated, causing the piston assembly 2 to move upward. At the same time, the sealing plug 4 also moves upward and opens the valve port 3, so that the compressed air at the upper end of the piston assembly 2 is discharged through the hole 6. After the piston assembly 2 moves upward, P

communicates with B, and A communicates with T (exhaust). At this time, even if D2 is powered off, the upward force due to the area difference between the large and small piston still exists, so the output state will not change, that is, it has a memory function. Pneumatic solenoid directional valves are the same as hydraulic solenoid directional valves. There are many types, and their working principles are similar, so I won’t go into details.