| 摘要 |
A personnel access door assembly of an opposing wing of a mine ventilation door. The personnel access door includes a frame including a top portion, a bottom portion, a first post portion and a second post portion, the top frame portion and the bottom frame portion coupled to respective top and bottom ends of the first post and second post portions. The personnel access door further includes sets of trolley wheels affixed to the top or bottom of the frame to engage a top rail or bottom rail affixed on the opposing wing. |
