Solenoid Valves are divided into three main categories: direct-acting, step-by-step direct-acting, and pilot-operated. The difference between the valve structure and the material and the principle are divided into six sub-categories: direct-acting diaphragm structure, step-by-step direct motion diaphragm structure, pilot diaphragm structure, direct-acting piston structure, step-by-step Direct acting piston structure, pilot piston structure.
1. Indirect pilot solenoid valve
The solenoid valve is formed by a combination of a pilot valve and a main spool to form a passage; the normally closed type is closed when not energized. When the coil is energized, the generated magnetic force causes the moving iron core and the static iron core to be sucked, the pilot valve port is opened, and the medium flows to the outlet. At this time, the pressure in the upper chamber of the main spool is reduced, lower than the pressure on the inlet side, forming a pressure difference against the spring. The resistance moves upwards to achieve the purpose of opening the main valve port and the medium is circulated. When the coil is de-energized, the magnetic force disappears, and the moving iron core is reset to close the pilot port under the action of the spring force. At this time, the medium flows in from the balance hole, the pressure in the upper chamber of the main spool increases, and moves downward under the action of the spring force. Close the main valve port. The normally open principle is just the opposite.
Principle: When energized, the electromagnetic force opens the pilot hole, the pressure in the upper chamber drops rapidly, and a pressure difference between the upper and lower parts is formed around the open member. The fluid pressure pushes the open member upward and the valve opens. When the power is off, the spring force leads the pilot. The hole is open, and the inlet pressure passes through the bypass hole to form a lower low and high pressure difference around the valve member, and the fluid pressure pushes the open member downward to open the valve. This is the case with Intelligent Toilet Solenoid Valve.
Intelligent Toilet Solenoid Valve
2, step-by-step direct-acting solenoid valve
The valve is integrated into one valve and the second valve is opened. The main valve and the pilot valve step by step to directly open the main valve port by electromagnetic force and pressure difference. When the coil is energized, an electromagnetic force is generated to cause the moving iron core and the static iron core to be sucked, the pilot valve port is opened and the pilot valve port is disposed on the main valve port, and the moving iron core is connected with the main valve core, and the main valve is connected at this time. The pressure of the chamber is unloaded through the pilot valve port, and the main spool is moved upwards under the action of the pressure difference and the electromagnetic force to open the main valve medium circulation. When the coil is de-energized, the electromagnetic force disappears. At this time, the moving iron core closes the pilot valve hole under the action of its own weight and spring force. At this time, the medium enters the upper cavity of the main valve core in the balance hole, so that the pressure of the upper chamber rises. The main valve is closed under the action of spring return and pressure, and the medium is interrupted. The structure is reasonable, the action is reliable, and the work is reliable when the pressure is zero.
Principle: It is a combination of direct motion and pilot type. When there is no pressure difference between the inlet and the outlet, after the power is applied, the electromagnetic force directly lifts the pilot small valve and the main valve closing member upward, and the valve opens. When the inlet and outlet reach the starting pressure difference, after the energization, the electromagnetic force leads the small valve, the pressure of the lower chamber of the main valve rises, and the pressure of the upper chamber drops, so that the main valve is pushed upward by the pressure difference; when the power is off, the pilot valve uses the spring The force or medium pressure pushes the closure and moves down to close the valve.
3, direct-acting solenoid valve
There are two types of normally closed and normally open. When the normally closed type is powered off, it is in a closed state. When the coil is energized, an electromagnetic force is generated, so that the moving iron core overcomes the spring force and directly opens the valve with the static iron core, and the medium is in a path; when the coil is de-energized, the electromagnetic force disappears, and the moving iron disappears. The core is reset under the action of the spring force, and the valve port is directly closed, and the medium is blocked. The structure is simple, the action is reliable, and it works normally under zero pressure difference and micro vacuum. The normally open type is just the opposite. Such as solenoid valves smaller than φ6 flow path.
Principle: When the normally closed type is energized, the electromagnetic coil generates electromagnetic force to lift the open member from the valve seat, and the valve is opened; when the power is off, the electromagnetic force disappears, and the spring presses the open member against the valve seat, and the valve is opened. (Normally open type is opposite)
The above is the description of the principle of the solenoid valve in the Water Inlet Solenoid Valve Factory, I hope to help everyone.