Securing screws against unauthorised access and theft

摘要

The sleeve (2) has one end open and the other closed (3) with a hole (4). The wall of the sleeve, at the open end, is made with the recess (5), shaped as those for bayonet fittings. The screw fits into the sleeve so that its shaft projects from the hole (4), as shown in the second figure, and so that it can then be screwed into some other part. To secure it, a key, consisting of a key (7) and locking cylinder (6) are inserted into the sleeve, and the locking cylinder is locked by turning in the bayonet fitting and then withdrawing.