Lock mechanism for a window

摘要

A locking mechanism includes: a rack member (10), for attachment to a window frame (1), which has an engagement surface (14) including a number of parallel ribs (12) extending along the surface in a first direction and a lock member (50), for attachment to a window sash (2), including an engagement surface (51) having a number of corresponding ribs (52) adapted to engage with at least some of the ribs (12) on said first engagement surface (14). The mechanism includes means (30,80) for maintaining said engagement surfaces (14,51) of said rack member (10) and lock member (50) in overlying relationship and means (15,70) for disengaging said rack member (10) and said lock member (50) by providing relative movement of said rack member and lock member in a direction substantially parallel to said ribs until said first (12) and second (52) plurality of ribs disengage, so as to open and close the window.