Safety protection door locking device

The utility model discloses a locking device of a safety protection door. The device comprises a rack and a safety door, wherein a locking mechanism for locking the safety door is arranged on the rack, the locking mechanism comprises a push-pull cylinder, a push-pull rod, a rotating shaft and a baffle, the push-pull cylinder is fixedly arranged on the rack, the rotating shaft is rotatably arrangedon a bearing seat through a bearing, the bearing seat is fixedly arranged on the rack, one end of the push-pull rod is fixed with the outer wall of the rotating shaft, and the other end is connectedwith a piston rod; one end of the baffle is fixed with the outer wall of the rotating shaft; when the safety door is pulled to an upper limit, the push-pull air cylinder pushes or pulls the push-pullrod to rotate around the rotating shaft, and the blocking portion of the baffle rotates synchronously and blocks the lower portion of the safety door or keeps away from the safety door. According to the locking device of the sa