1. Action methods can be divided into three categories: Direct-acting. Pilot-operating. Step-by-step direct-acting 1. Direct acting principle: When the normally open and normally closed direct acting solenoid valve is energized, the magnetic coil generates electromagnetic suction, lifts the valve core, and keeps the closing part away from the valve seat sealing pair; when the power is off, the magnetic field force subsides, and the closing part is pressed by the spring force The gate valve on the seat is closed. (normally open, ie) Features: It can work normally in vacuum, negative pressure and zero differential pressure, but the solenoid head is bulky, and its power consumption is greater than that of the pilot solenoid valve, and the coil is easily burned when energized at high frequency. But the structure is simple and widely used. 2. Principle of pilot-operated solenoid valve: When the power is turned on, the solenoid-operated hydraulic control valve opens the pilot valve, the pressure in the upper chamber of the main valve decreases rapidly, and a pressure difference is formed in the upper and lower chambers. , the spring force closes the pilot valve, and the inlet medium pressure quickly enters the upper chamber of the main valve through the pilot hole to form a pressure difference in the upper chamber to close the distribution valve. Features: Small size, low power, but the medium pressure difference range is limited, must meet the pressure difference standard. The electromagnetic head is small, the power consumption is small, it can be energized frequently, and it can be energized for a long time without burning and saving energy. The liquid pressure range is limited, but it must meet the liquid pressure differential standard, but liquid impurities are easy to block the liquid pilot valve hole, which is not suitable for liquid applications. 3. The principle of step-by-step direct-acting solenoid valve: its principle is a combination of direct-acting and piloting. When the power is turned on, the solenoid valve first opens the auxiliary valve, the pressure in the lower chamber of the main distribution valve exceeds the pressure in the upper chamber, and the valve is opened by the pressure difference and the solenoid valve at the same time; when the power is off, the auxiliary valve uses the spring force or material pressure to push the closing part and move down. close the valve. Features: It also works reliably at zero pressure difference or high pressure, but the power and volume are large, and vertical installation is required. 2. According to the work position and work port Two-way two-way, two-way three-way, two-part five-way, three-way five-way, etc. 1. The two-position two-way spool has two positions and two ports. Generally, the air inlet is (P), and one is the exhaust port A. 2. The two-position three-way spool has two positions and three ports. Generally, the air inlet is (P), and the other two are the exhaust ports (A/B). 3. The two-position five-way valve core has two positions and five connection ports. Generally, the air inlet is (P), the A and B ports are the two air outlets connecting the cylinder, and the R and S are the exhaust ports. 4. Three-position five-way three-position five-way means that there are three working positions, generally controlled by double electricity. When the two electromagnets cannot be energized, the valve core is in the middle position under the promotion of the balance of the torsion springs on both sides. . 3. According to the control method Single electric control, double electric control. Mechanical control. Pneumatic control.
Post time: Jul-13-2022