R901096044 Rotary cylinder balance spool solenoid valve

        It consists of a control cover plate 1, a cartridge unit (consisting of a valve sleeve 2, a spring 3, a valve core 4 and a seal), an cartridge block 5 and a pilot element (placed on the control cover plate, not shown in the figure). Because the cartridge unit of this valve mainly plays the role of controlling on and off in the loop, it is also called two-way cartridge valve. The control cover plate encapsulates the cartridge unit in the cartridge block and communicates the pilot valve and the cartridge unit (also known as the main valve). Through the opening and closing of the main valve spool, the main oil circuit can be controlled. The use of different pilot valves can constitute pressure control, direction control or flow control, and can be composed of composite control. A hydraulic circuit is formed by assembling a number of two-way cartridge valves with different control functions in one or more cartridge blocks.
 

       In terms of the working principle of the cartridge valve, the two-way cartridge valve is equivalent to a hydraulic control check valve. A and B are the only two operating oil ports of the main oil circuit (called two-way valves), and X is the control oil port. Changing the pressure of the control oil port can control the opening and closing of the A and B oil ports. When the control port has no hydraulic action, the liquid pressure under the valve core exceeds the spring force, the valve core is pushed open, A and B are connected, and the direction of the liquid flow depends on the pressure of the A and B ports. On the contrary, the control port has A hydraulic effect, and when px≥pA and px≥pB, it can ensure the closure between port A and port B. In this way, it plays the role of the "not" gate of the logic element, so it is also called the logic valve.

       Cartridge valves can be divided into two categories according to the source of the control oil: the first type is the external control cartridge valve, the control oil is supplied by A separate power source, its pressure is unrelated to the pressure change of A and B ports, and it is mostly used for the direction control of the oil circuit; The second type is the internal control cartridge valve, which controls the A or B port of the oil inlet white valve, and is divided into two kinds of spool with damping hole and without damping hole, which is widely used.