Stopper servo hydraulic cylinder

The present invention discloses a stopper servo hydraulic cylinder. One end of a protective cover is fixed on a front cylinder cover, and the other end is fixed on a front fork to extend and retract with a piston rod to prevent dust and iron powder from damaging the piston rod. A ball valve is connected with a cylinder body. The ball valve opens to release pressure for two chambers and closes to realize pressure isolation between two chambers. The cylinder body is fixed with the front end cover and a rear end cover through a stud and a nut. A rear cylinder cover sheath is fixed on the rear cylinder cover through a screw to protect the piston cylinder from being damaged and to facilitate manually detaching the cylinder. A transmission sheath is fixed to the rear end of the rear cylinder cover sheath through the screw to protect a built-in displacement sensor from being damaged. A wire jacket is welded on the transmission sheath to allow a transmission cable to pass through and to wear afireproof covering outsi