Principles and characteristics of stepped direct-acting solenoid valve?
This kind of valve uses one-time valve and two-time valve to be connected together. The main valve and pilot valve make the electromagnetic force and pressure difference directly open the main valve. When the coil is energized, an electromagnetic force is generated to attract the moving iron core and the static iron core. The pilot valve port is opened and the pilot valve port is set on the main valve port, and the moving iron core is connected to the main valve core. The pressure in the cavity is unloaded through the pilot valve port, and the main valve core is moved upward under the simultaneous action of pressure difference and electromagnetic force, and the main valve medium is opened to flow. When the coil is de-energized, the electromagnetic force disappears. At this time, the moving iron core closes the pilot valve hole under the effect 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 to increase the pressure of the upper cavity. Under the action of spring return and pressure, the main valve is closed, and the medium is cut off. The structure is reasonable, the action is reliable, and the work is reliable at zero pressure difference.
Principle: It is a combination of direct-acting and pilot-operated principle. When there is no pressure difference between the inlet and the outlet, after the power is turned on, the electromagnetic force directly lifts the pilot small valve and the main valve closing part upwards, and the valve opens. When the inlet and outlet reach the starting pressure difference, after power is applied, the electromagnetic force pilots the small valve. The pressure in the lower chamber of the main valve rises, and the pressure in the upper chamber decreases, so that the main valve is pushed upward by the pressure difference. Force or media pressure pushes the closing piece and moves down to close the valve.
Features: It can operate under zero pressure difference or vacuum, and high pressure, but the power is attenuated, and it must be installed horizontally.