Coal mine automatic ventilation air door device

The utility model discloses an automatic ventilation air door device for a coal mine. The air door device comprises an air door device body matched with a roadway. The air door device body comprises two air blocking doors and a pneumatic door opening mechanism. A driving cylinder is arranged on the pneumatic door opening mechanism; a first mounting block is fixedly mounted on one side of one of the two air blocking doors; a second mounting block is fixedly mounted on one side of the other windshield door, a first groove with an opening in one side is formed in the side, close to the second mounting block, of the first mounting block, a rectangular block is fixedly mounted on the side, close to the first mounting block, of the second mounting block, and a triangular clamping rod is fixedlymounted on the side, away from the second mounting block, of the rectangular block. The air blocking door is reasonable in design and convenient to operate, the air blocking door can be conveniently locked and fixed after bei