Mine door system including an air pressure relief door

摘要

A mine door of the present invention is adapted for installation in a mine passageway and includes a leaf adapted for swinging between a closed position and an open position. The leaf may be mounted in a frame, and a stopping wall may surround the frame. When closed, the leaf is subject to a differential in air pressure involving higher pressure on one of the faces of the leaf than on the other of the faces of the leaf. The leaf, the frame, or the stopping has an opening therein for passage of air therethrough from adjacent the one of the faces of the leaf to adjacent the other of the faces to more nearly equalize the pressure on the faces and thereby facilitate opening the leaf.