Power mine door system

摘要

A power mine door system including a door frame to be installed in a mine passageway to define a generally rectangular doorway. A mine door is hinged on the door frame for swinging between open and closed positions. A power means for opening and closing the door comprises a fluid-actuated cylinder 124, a fluid circuit including electric fluid supply means 122 for supplying fluid to the cylinder, and accumulator means 120 for supplying fluid to the cylinder to operate the door in the event of an electric failure.