| 摘要 |
The present invention relates to an electric hydraulic actuator capable of discharging air. The electric hydraulic actuator includes: a cylinder unit having a first port to which a hydraulic oil is supplied, a second port from which the air is discharged, and a third port in which the air is circulated, wherein a space in which a piston is inserted and driven is formed inside the cylinder unit; a servo valve unit mounted and guided by a bracket unit installed on the outer side of the cylinder unit and controlling operation of the actuator by supplying the hydraulic oil to the inside of the cylinder unit to pressurize a piston unit; the piston unit having a piston head and a piston rod and driven by the hydraulic oil supplied from the servo valve unit by being inserted into the cylinder unit; an output unit outputting a driving force by being connected to the piston unit; and an air vent valve installed in a first rod end cap of the cylinder unit and discharging the air in the cylinder to the outside through the second port installed in the first rod end cap. The air vent valve includes: a valve body having a body unit and a discharge flow path and discharging the air in the cylinder to the outside since the discharge flow path is connected to the second port; a valve spool accommodated in the valve body and reciprocating in the valve body by the hydraulic oil; a valve elastic member arranged between the valve body and the valve spool and elastically biasing the valve spool; and multiple throttle units formed at fixed intervals on one among the valve body and the valve spool in a moving direction of the valve spool, with a gap wider than a gap between the valve body and the valve spool and throttling the hydraulic oil flowing into the gap. |
