Patent ID: 7396341

Claim:
Blocking device for an apparatus which comprises a locking-stressing-mechanism with an operating spring and a spring transfer member in which is accommodated a piston which is mounted to be moveable in a cylinder, and these components are housed in a two part housing which comprises an upper housing part and a lower housing part, said upper housing part having an inner wall and said lower housing part having an outer wall, and the two parts are mounted to be rotatable relative to each other, and said operating spring is tensioned by means of a screw thrust gear by manually rotating said two housing parts relative to each other, and at the same time as said housing parts are rotated relative to each other a mechanical counter is actuated which comprises a threaded spindle and a slider, and said threaded spindle is mounted in said wall of the lower housing part, and said slider is moved along said spindle by an amount which depends on the number of rotations of said two housing parts relative to each other, wherein a recess is provided in said outer wall of said lower housing part and in said inner wall of said upper housing part, and the two recesses are opposite each other when said two housing parts are in a given rotary position, and a moveable blocking element is provided which is located initially only in the recess in said lower housing part and a push rod for moving said blocking element partially into the recess in said upper housing part to prevent the upper and lower housing parts from rotating relative to each other is provided which cooperates with said slider on said spindle of said counter.