摘要 |
A window system comprises a frame having a top, a bottom and two sides, at least one slidable and tiltable sash disposed within the frame, and a locking device attached to each side of the sash. The locking device is pivotable between an unlocked position to permit tilting of the sash, and a locked position which locks the sash to the frame. In the locked position, the locking device prevents any air from infiltrating between the sides of the sash and the frame. |