GB299958A - Improvements in and relating to locking fittings for windows, doors, fanlights and the like - Google Patents

Abstract

299,958. Elliott, R. Sept. 19, 1927. Latches, sliding, for securing windows, doors and like articles in one or more positions, are, when withdrawn, held back by a lever which is tripped to release the latch when a trigger engages an inclined surface on closing the window. The latch bolt a can engage either of the holes h, h<1> in a plate g in the frame. It is withdrawn by a lever c one arm c<1> of which is so shaped that it co-operates with a shoulder a<2> of the latch to hold it withdrawn against the spring e<2>. Arms c', c<5> protrude the trigger b. On moving the sashes, the trigger b rides over the incline j on the upper sash and trips the lever c, releasing the latch which is forced into the hole h or h<1> by the spring when it reaches alignment therewith. An arm c<3> prevents the trigger from protruding when the latch is withdrawn. The casing d containing the latch-mechanism may be mounted on a casement window, or hinged door, the plate g being then mounted on the frame. A lip g<1> on the plate g prevents the entry of a knife between the sashes for tampering with the latch bolt. In the form shown in Fig. 13, the latch a has a curved bifurcated end co-operating with the limb o<1> of a lever c, which is rocked out of position for retaining the latch in the withdrawn position by the trigger b. Instead of a bifurcated end, the bolt may have a stud engaging notches s.