Electro-hydraulic servo-valve controlling actuator or motor

摘要

The electro-hydraulic servo-vavle (11) has a limited rotation electric motor (12) driving a hydraulic distributor (16) with a rotating head (18). An electronic controller drives the motor to position the valve. The valve head has transverse passages to allow passage of fluid when the head is rotated so it faces delivery conduits. The valve has a mechanism (31) to ensure the return of the head to its initial position after the drive signal is removed from the motor. A torsion bar (31) is fitted inside a tubular part of the head, coaxially with the head, with one end attached to the valve housing while the other end is linked to the valve head.