device for the ventilation of tunnels and the like, in particular for mines

摘要

The supply of fresh ventilation air to a tunnel is improved by blowing, by means of a fan or air mover, air along one wall of the tunnel, or along the ceiling of the tunnel, and by moving said fan or air mover forward and backward in the tunnel. The air in the tunnel is stratified, and therefore the ventilation is effective also in tunnels of a considerable length.