Overspeed protecting device of air compressor

The utility model relates to an overspeed protecting device of an air compressor, belonging to the overspeed protecting device which runs under a safe working speed in protection equipment. Three magnetoelectric probes of the overspeed protecting device of the air compressor are evenly arranged on a speed detecting disk of the air compressor, the three magnetoelectric probes respectively enter into three passageways of an electric overspeed protector, the three passageways of the electric overspeed protector are respectively connected with a relay, each relay is connected with an electromagnetic valve, three electromagnetic valves are evenly arranged on the outer wall of a two-in-three redundancy speed gate, the two-in-three redundancy speed gate is internally provided with three oil ways, and three outlets of the three electromagnetic valves are respectively connected with the three oil ways of the two-in-three redundancy speed gate. The overspeed protecting device can timely and exactly perform the vehicle