Composition of electro-hydraulic servo valve

     There are many types and structural forms of electro-hydraulic servo valves, but they all consist of two parts: electro-mechanical converters, and hydraulic amplifiers. The electro-mechanical converter transforms the small power electrical signal into the motion of the valve, and then controls the flow and pressure of the hydraulic fluid by the motion of the valve. The output force or torque of the electro-mechanical converter is very small, and in the case of relatively large flow rate, it cannot be used to drive the power valve directly. At this time, a hydraulic pre-amplifier stage is added to amplify the output power of the electro-mechanical converter and then control the valve, which constitutes a multi-stage electro-hydraulic servo valve. The pre-amplification stage can usually use a slide valve, nozzle baffle valve or jet pipe valve. Compared with the ordinary solenoid valve or point this proportional valve, the electro-hydraulic servo valve has a very small input signal power, and is able to control the output flow and pressure continuously in both directions, and has a very fast response speed and high control accuracy. Therefore, it can be used to form a high-precision closed-loop control system.