Ventilation device for coal mine gas prevention and control

The ventilation device comprises a box body, a ventilation pipe is arranged in the box body, the two ends of the ventilation pipe are detachably connected with dust removal bags respectively, the two ends of the ventilation pipe are sleeved and fixedly connected with separation assemblies respectively, and the outer side face of the ventilation pipe is fixedly connected and communicated with an external air inlet pipeline. The air inlet pipeline penetrates through the side wall of the box body, one side of the box body is fixedly connected and communicated with an air outlet pipeline, and the air outlet pipeline is arranged between the two separation assemblies; two switching assemblies are arranged in the ventilation pipe, a crankshaft is rotationally connected between the two switching assemblies, one end of the crankshaft penetrates through the ventilation pipe and is rotationally connected with the ventilation pipe, one end of the crankshaft is in transmission connection with the separation assembly, the