| 摘要 |
The present invention relates to locks which use shoot bolts to secure a window or door in its closed position, and more particularly, but not exclusively, to a two point lock for use in bi-fold windows and doors. There are unique challenges to meeting the demands of bi-fold doors, such as having a thin housing to fit with the frame. The present invention also has improved security. The present invention uses a two point lock for securing bi-folding windows and doors in which upper and lower shoot bolt arms 32, 34 move in opposite directions from a central lock body 30 upon rotation of a handle 14. When the arms are in their mutually extended positions, a sliding detent locking member 50 can be engaged through an elongate slot of the upper shoot bolt arm 32 to secure the upper shoot bolt arm and hence the window or door in the closed position. This configuration has the effect of reducing the size of the locking member and as such the lock housing, and the shoot bolts can be locked in their extended position in more secure manner so as to be more resistant to being overcome by force. |
