抄録
This study describes a prototype of a servo valve to control motion of water hydraulic actuators. The structure of the servo valve is not conventional spool valve, but rotary-type valve to downsize and reduce cost. The rotary valve plate has the conduit hole to switch the ports. The metering edge is composed by the conduit holes of the rotary valve plate and the valve bodies. The rotary valve plate is connected to a servo motor that determines the rotational angle of the valve plate. Even if the valve plate and the valve body are worn away, they can be ground and reused. For water hydraulics, the thrust force acting on the rotary valve plate should be reduced because the water has poor lubricity. Therefore, several holes were made through the valve plate, so that the pressure distributions in both clearance become equal.
