Patent ID: 8800204
Filing Date: 2014-08-12
Classification: E05F,E05Y,E06B,E21F

Abstract:
1. A mine door system comprising a mine door comprising at least one door leaf adapted to be hinged to a door frame defining an entry, and a door-moving mechanism, said door-moving mechanism, when moving said door leaf, is movable between a first configuration in which the mechanism applies a first door-moving force to the at least one door leaf and moves the at least one door leaf at a first speed and a second configuration in which the mechanism applies a second door-moving force larger than the first door-moving force to the at least one door leaf and moves the at least one door leaf at a second speed less than the first speed, said door-moving mechanism, when opening said door leaf, is configured to assume said second configuration to move the at least one door leaf through an initial-opening segment of movement against an initial load on the at least one door leaf and to assume said first configuration in response to a decrease in said initial load on the door leaf as the door leaf continues to open, said door-moving mechanism comprising: