ELECTROHYDRAULIC SERVO UNIT AT MECHANICAL LIMIT OF ACTUATING ROD TRAVEL Russian patent published in 2006 - IPC B64C13/36 

FIELD: aeronautical engineering.

SUBSTANCE: proposed servo unit has body with electrohydraulic booster, actuating mechanism piston with rod, electrically-operated change-over valve with pressure chamber connected with return line and command cavity. Bush fitted on rod is movable relative to body and rod and is provided with circular projection at end face inside body. Provision is also made for circular groove for receiving balls of mechanical lock made in form of spring-loaded piston located concentrically relative to rod and provided with circular groove for balls on its internal surface. Mechanical lock cavity where spring is located is connected with return line and other cavity is connected with command cavity of electrically-operated change-over valve.

EFFECT: deliberate limitation of actuating mechanism rod travel.

1 dwg