The role of an electro-hydraulic servo valve
The electro-hydraulic servo valve is both an electro-hydraulic conversion component and a power amplifier component, which can convert a low-power electrical signal into a high-power hydraulic signal. Electro-hydraulic servo valve has the advantages of small size, compact structure, high amplification factor and good control performance, and has been widely used in electro-hydraulic servo system.
Two-moment motor
The torque motor converts the input electrical signal into the torque output. It is mainly composed of a pair of permanent magnets l, upper and lower magnetic conductors 2 and 4, armature 3, coil 5 and spring tube 6. A permanent magnet magnetizes the upper and lower two magnetic conductors into the N and S poles. When there is no control current, the armature is supported by a spring tube in the middle position of the upper and lower magnetic conductor, and the torque motor has no output. When there is a control current, the armature is magnetized. If the left end of the armature is the N pole and the right end is the S pole, the armature deflects in the counterclockwise direction due to the principle of same-sex repulsion and opposites attraction. At the same time, the spring tube bends and deforms, resulting in an inverse moment until the electromagnetic moment is balanced with the reverse moment of the spring tube. The larger the current, the larger the electromagnetic torque generated, and the larger the Angle θ of the armature deflection.
Hydraulic amplifier
The torque generated by the torque motor is very small, and it is impossible to directly manipulate the slide valve to produce sufficient hydraulic power. Therefore, hydraulic amplifiers generally use two-stage amplification.
