GB397980A - Improvements in and relating to lock and latch mechanism - Google Patents

Abstract

397,980. " Engaged " indicators. KAYE, J. V. and COOPER, S., Lock Works, Hunslet, Leeds. May 24, 1932, No. 14667. [Class 118 (i).] In a door fastening provided with an " engaged " indicator a slidable member handoperable from inside the door has a stud which serves to lock the latch bolt against handoperation from outside and at the same time operates the indicator, the locking means and indicator being operable from outside by means of a key. The bolt B mounted in a mortise casing C, is shot by a spring S and is retracted by handles on a spindle A. A knob-operated slider D2 mounted in a separate casing Dx on the inner face of the door has a stud D passing through slots in casing C into engagement with an indicator plate G<2> vertically movable in a casing G on the outer face of the door and provided with a sight-opening G<1>. Plate G<2> falls under gravity and is raised by stud D co-operating with a cam edge G<3> on the plate. Stud D fits an aperture in a member L slidable in casing C and passes freely through a slot B<3> in bolt B. Member L is gated at its lower edge L<3> to co-operate with a key inserted through registering key-holes K<1>, K in cases G, C respectively. When member L is moved to the left, Fig. 1, by hand from inside or by key from outside its projecting corner L<4> tilts a cranked spring-biased lever F causing the end of its lower limb to engage a recess B<7> in the bolt, locking it against hand-operation, plate G being simultaneously raised to " engaged" position.