| 摘要 |
<p>CRASH BAR DOOR LOCKING DEVICE A crash bar door locking device is provided, suited for mounting on the inside of a swinging door. The crash bar is mounted horizontally across the door providing ready access by movement in the outside direction. The crash bar activates a pivotal lever which causes a latch bolt to rotate inwardly and disengage from a door strike. The pivotal lever provides a deadbolt feature by preventing the rotation of the latch bolt. A release is incorporated in the latch bolt and allows the latch bolt to rotate when the release engages the door strike as the door closes. An additional unlocking mechanism may be provided for retracting the latch bolt from the outside of the door independently of the crossbar. A firelocking mechanism may be incorporated in the latch bolt to secure the latch bolt when a fire occurs. Two pins with a spring between them are retained by fusible plugs at either end of a bore in the latch bolt, so that the latch bolt operates as normal lock on the door. When a fire occurs, the fusible plugs will melt and the pins will go to an extended position in which they interact with a bracket mounted on the door and prevent the latch bolt from disengaging the door strike so that the door will remain closed.</p> |
