| 摘要 |
<p>A theft proof device for pictures and other valuable objects, consists of a base plate (1) with ribs (16), towards the wall and fixed to the wall by screws (5). The surface of the base plate has two sets of slots in a labyrinth combination. Each set starts off with a hole (7) large enough to pass the heads of a bolt (13) projecting from the back of the picture frame. The picture then has to be moved along the labyrinth slots with the aid of a plan of the shape of the labyrinth slots, until resting spots (15) are reached. These spots have recesses into which washers on the bolt heads come to rest. The labyrinth pattern has also a system of "dead ends" to make the removal of the picture to unauthorised persons impossible.</p> |
