GB1487567A - Lock - Google Patents

Abstract

1487567 Lock GKN-STENMAN AB 12 Dec 1974 53867/74 Heading E2A A lock of the type requiring a complete revolution of an appropriate. key to bring the lock to a fully locked conditionhas a bolt 2, at least one lock cylinder, at least one operating means which is rotatable by said lock cylinder or cylinders and is arranged to displace an operating member 7 between two limit positions during at least part of. a rotation of the operating means, the arrangement being such that the operating means can enter into or move out of engagement with the operating member 7 when said operating member is in either of the limit positions, a toothed rack 7a on the operating member 7, a pivotally mounted arm member 8 associated with the bolt 2, the arm member being pivotable at 9 to displace the bolt, via linkage, between a locking position and a release position, the arm member 8 having a toothed segment 8a engaging with the toothed rack 7a so that displacement of the operating member 7 causes pivoting of the arm member 8, a link 16, 17 co-operating with the arm member 8 and defining therewith a toggle linkage arranged to move overcentre during displacement of the bolt between the locking and release positions, and a spring arranged to bias said toggle linkage towards the mutually oppositely cranked conditions thereof on either side of the straight or centre condition. In an embodiment lock cylinders 5, 5' are actuated by operating means comprising followers 6, 6' in bearings 4, 4' respectively. Projections 6a, 6'a of the followers 6, 6' can be received in a recess 7b in the operating member 7 when the latter is in either of its limit positions. Thus either lock cylinder 5 or 5' can displace the member 7 by a partrotation of a key (not shown) so as to move the bolt 2 to its locked position as shown in Fig. 1 or to its released position as shown in Fig. 3. The followers 6, 6' are each provided with a recess for engagement by a spring 20 which is supported at 21 and ensures that the followers are positioned so as to allow the insertion or removal of the key (not shown).