Improvements in or relating to means for preventing movement of catches for casementwindows, french windows, turn buttons and the like

摘要

405,109. Window &c. fastenings. CRITTALL MANUFACTURING CO., Ltd., and CRITTALL, W. F., Manor Works, Braintree, Essex. Jan. 17, 1933, No. 1582. [Class 44.] A casement window fastener 21 is secured by a sliding bolt 6 moved by hand to engage under the fastening arm 18 and retained by a spring- pressed detent 13 which can be disengaged from the bolt by a key 25 arranged at about 45‹ to the plane of the window and pointing inwards towards the window 20. The bolt 6 of triangular crosssection slides in a triangular casing consisting of a back plate 1 and a cover plate 2 secured thereto by screws, and has a triangular recess 29, the V-sectional portion thus formed sliding in a correspondingly shaped channel in the casing, between a triangular rib 5 and the cover plate 2. The bolt is pressed to its inoperative position by a spring 10 housed in the recess 29. The rib 5 receives the screws 8 whereby the casing is secured to the fixed frame 9 so that the side face 16 of the back plate is flush with the side face of the flange of the fixed frame and no plaster has to be cut away. The spring-pressed detent 13, housed in a recess 11 in the casing, engages with an aperture 15 in the bolt and can be withdrawn by a key 25 which engages with a notch 23. Projections may be provided on the casing so that a special key is required to operate the detent. The casing may be formed with another recess 12 for the detent so that it may be inverted for an oppositely opening window, the plunger being suitably modified. The fastener 21 abuts against a fixed stop 22 on the window when fastened. The surface of the striking plate 28 which is inclined as usual lies flush with the surface of the back plate. When the window is closed, the back plate 1 and the bolt 6 lie close against the window 20 to prevent the entrance of a tool for forcing the window.