Mining ventilation air door

The utility model relates to the technical field of mine ventilation air doors, and discloses a mine ventilation air door which comprises an air pipe, an annular groove is formed in the inner wall of one end of the air pipe, a gear ring is rotatably arranged in the annular groove, a second sieve plate, a third sieve plate and a second baffle are fixedly connected to the inner wall of the gear ring, a notch is formed in the outer surface of the air pipe, and the second baffle is fixedly connected to the inner wall of the gear ring. The air outlet amount of the air pipe on one side of the gear ring is controlled by starting the motor and adjusting the rotating positions of the second sieve plate, the third sieve plate and the second baffle, so that the overall air outlet efficiency of the air pipe is adjusted, and when the second baffle rotates to coincide with the first baffle, the device does not discharge air, and the device does not discharge air. The whole device is easy to operate, manual repeated adjustm