GB223119A - Improvements in and relating to safety locks - Google Patents

Abstract

223,119. Dorneth, J. Feb. 19, 1924. Locks, revolving-barrel; night latches and like spring locks; bolts; multiple-bolt fastenings.-A revolving-barrel lock with radially-arranged notched sliding tumblers operates two or more spring-shot bolts which are normally held retracted by a catch till the door is closed, when their springs shoot them and effect turning of the barrel to a position in which the tumblers engage fixed studs to lock the barrel. The revolving-barrel is composed of the key-barrel 5 journaled in the front and back plates of the lock and having rigidly secured to it the member 4 with slots p for guiding the tumblers 11. The tumblers 11 have notches l co-operating with fixed studs 2 arranged circularly on the baseplate 1. The part of these studs engaging the tumblers is semicircular. Each tumbler has two projections h entering holes in the key-barrel 5 to project into the bore to co-operate, with the key. The projections h fall one on each side of the partition k, so that if the outside projections are destroyed by tampering the inside ones remain intact. To operate the lock, the key is inserted into the key-barrel to align the notches L of the tumblers with the studs 2, when the barrel can be turned to cause the follower a to withdraw the bolts 7 from the staples 9 against their springs c. When the bolts are withdrawn a catch b pivoted to a bracket on the bolt is turned by the spring c to engage under the staple 9, as shown in Fig. 3, to hold the bolt withdrawn. When the door is opened, the shoulder d on the catch engages the plate 8, still holding the bolt withdrawn, ae shown in Fig. 4. When the door is slammed, the catch b is knocked out of engagement with the plate 8 by the staple 9, allowing the spring c to shoot the bolt. The necessary turning of the follower a and barrel to allow this shooting of the bolt is possible owing to the rounded backs of the pins 2 engaging the bevelled edges m of the tumblers 11 which are forced into releasing position against their spring 14 to allow the barrel to turn as the bolt shoots, after which they snap back into locking position. The bolts 7 have a tubular outer part with a revoluble inner core to prevent release by drilling.