ADJUSTABLE STAIRWAY FOR USE WITH AN OVERCAST IN A MINE

摘要

An overcast system for a mine is disclosed. The system includes and overca st positioned at an intersection of mine passageways and operable to direct airflow through the passageways in a desired flow pattern at the intersection. Stairways are positioned adjacent opposite sides of the overcast providing a means for people to traverse between the opposite sides of the overcast. The stairways are self adjusting to accommodate overcasts of different heights while providing generally horizontal steps. T he stairways are constructed with knockdown assembly means to provide for easy assembly a nd disassembly in the mine.