GB190312517A - Improvements in Locks or Fastenings for Doors. - Google Patents

Abstract

12,517. M÷ller, C. B. S. June 2. Locks, key; latches; sliding bolts. - A latch bolt for a door is so arranged that it can be locked in the shot position. A spring-controlled bolt a is provided with an extension c, the inclined surface of which is engaged by a pivoted spring-controlled tumbler d. The tumbler has a projection h extending through a slot in the casing, and has an arm i for the engagement of a key. The projection h is engaged by an arm m of a pivoted handle or door knocker. Upon depressing the tumbler d, the bolt a is retracted, the arm m coming against a stop q to prevent the tumbler from being moved too far. Upon releasing the handle, the bolt is shot by the spring. In order to lock the bolt in the shot position, a key is inserted and brought into engagement with the arm i. Upon turning the key, the tumbler is pressed downwards out of engagement with the bolt, which is then shot by the spring. Upon returning the key, a catch r on the tumbler takes behind the nose s on the extension c. To unlock the door, the key is turned to withdraw the catch r and nose s from engagement and is then further turned to engage a projection v on the bolt. Knobs t, u may be provided on the bolt and tumbler for operating the lock parts. In a modification, handles and keyholes are provided on both sides of the door.