GB734517A - Improvements in or relating to door locks - Google Patents

Abstract

734,517. Locks. HELFENSTEIN, M. July 4, 1952 [Dec. 15, 1951], No. 16796/52. Class 44. In a door lock of the type having an inner and an outer handle arranged on the same spindle axis, a latch bolt is provided as sole closure element, the shifting of which is exclusively effected by the door handles and control means are adapted to be operated by actuating the inner door handle to bar the outer door handle which may be released from the outside by means of a key, or to bar the outer door handle, by corresponding setting of the inner door handle by means of a control member, so that its release by means of the key is not possible. As shown, an inner door handle 4 is rotatably mounted on a spindle 2 to which is rigidly connected an outer handle 3. A control disc 6 is carried by the handle 4 and a main lever 5 is carried on a square portion of the spindle 2. A nose 5c on the lever 5, serves to move the latch bolt 9 against a spring 8. A locking lever 10 is journaled on a pin 18 on the lever 5 and cooperates with a member 11 rigid with a toothed wheel 13 journaled on a shaft 12. The toothed wheel 13 meshes with a pinion 17 attached to a key-operated lock cylinder. A sliding bolt 14 is movable into the path of the bolt 9 by the member 11. In operation, both handles may be operated from the position shown in Fig. 1, i.e. the door can be opened from the inside or the outside of the room. In order to lock the door from the outside, the pinion 17 is turned by the key through 360 degrees to the Fig. 4 position, to move the bolt 14 into the blocking position shown. In this position also, neither of the handles can be operated. To lock the door from inside the room, the inner handle 4 is turned anticlockwise through 120 degrees, thus moving the disc 6 which rotates a lever 21 to engage a lug 21b thereon with the tail of the bolt 9 to lock the latter in the shot position. If the handle 4 is turned through 90 degrees only, the lever 10 and member 11 engage each other to prevent movement of the lever 8 and the outer handle 3, but not the bolt 9, which is retractable by the outside handle only after the key has been turned through 180 degrees in the opening direction to release the lever 5. In this position the key can only be removed after the pinion 17 has been restored to the position shown in Fig. 1.