Mine ventilation air increasing device

The utility model discloses a mine ventilation air increasing device, and particularly relates to the technical field of mine ventilation, the mine ventilation air increasing device comprises an air duct, one end of the air duct is provided with an air collecting hopper, the other end of the air duct is provided with an air outlet cover, the end part of the air outlet cover is detachably connected with an air conveying pipe, and a fan is arranged in the air duct; and the two supporting seats are symmetrically arranged on the bottom side of the air duct, storage cavities are formed in the bottom ends of the interiors of the supporting seats, and bidirectional screw rods are rotationally installed at the top ends of the interiors of the storage cavities. The bottom end of the supporting base is provided with the containing cavity, the two-way screw, the movable blocks, the connecting rods, the fixing plates and other structures, under the cooperation of the driving mechanism, the two fixing plates can drive the