Patent ID: 6941778
Filing Date: 2005-09-13
Classification: E05B,Y10T

Abstract:
1. A lock for a wing movable between respective open and closed positions relative to a frame comprising a casing a bolt operable to extend from or to retract into said casing, an operating member arranged to be operable at one side of the wing, in use, to effect retraction of the bolt, first lock means arranged, in use, for operation at the other side of the wing, and blocking means operable from said one side of the wing, in use, to prevent operation of the operating member to retract the bolt, the arrangement being such that, in use, in a locked, closed position of the wing said bolt is extended and said blocking means, if operated, prevents retraction of the bolt by said operating member, operation of said first lock means both de-actuating said blocking means, if operated, and retracting the bolt, wherein the blocking means can be actuated from said one side only of the wing to prevent operation of the operating member to retract the bolt, wherein the blocking means are operable to prevent operation of the operating member to retract the bolt by second lock means at said one side of the wing; wherein said second lock means are operable at said one side of the wing to de-actuate the blocking means, and wherein the blocking means is an angularly moveable cam.