Closing device with a lock cylinder for a locking function which can be executed particularly on motor vehicles

摘要

The lock proposed has a cylinder made up of a sleeve and a core. The core is locked to the sleeve by means of tumblers when the key is withdrawn and carries one of the elements of a longitudinal two-element coupling. When the inserted key is turned, the cylinder core is rotated and this movement is transmitted to the other element of the two-element coupling which is non-rotatably linked to an engaging lug. It is the engaging lug which carries out the vehicle-locking function. Although the cylinder sleeve is rotatably mounted in a fixed housing, it is normally prevented from rotating in the housing by means of a catch which acts as an overload protection mechanism. The catch consists of a male and a female snap-in element on the cylinder sleeve, which are spring-biased with respect to each other and normally engage in each other along a longitudinal section and can be disengaged. When turned by force, the male catch element is disengaged out of the female catch element and the cylinder is brought into a freely turning overload condition within the housing. At the same time, the two coupling elements are detached from each other. So that the cylinder does not move longitudinally in the event of an overload, the invention proposes that the cylinder sleeve is mounted in the housing so that it cannot move longitudinally. While the male catch element of the overload protection mechanism cannot be rotated, it can be displaced along the longitudinal axis of the housing. The longitudinally acting spring bias acts on the male catch element in the direction towards the female catch element which cannot move longitudinally in the housing. The coupling element mounted on the cylinder core also cannot move longitudinally, but the other coupling element can move longitudinally together with the male catch element against the bias of the spring.