| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a crime prevention lens provided with an inner cylinder impossible of rotation and removal from the exterior side and used for a single door and for a double door in common. SOLUTION: An inner cylinder 1 is inserted into a mounting hole 30 in an exterior side door plate 3 of a double door from the exterior side, and a seat part 13 of an exterior side flange part 10 is inserted and fitted in the mounting hole 30, while an outer cylinder 2 is inserted into a mounting hole 40 in an interior side door plate 4 from the interior side. When female and male screw parts 21, 11 are screwed for clamping the door plates 3, 4 by means of the exterior side flange part 10 and the interior flange part 20, a rotation stopping mechanism restricting rotation of the inner cylinder 1 is actuated. For example, the rotation stopping mechanism is constructed of an engaged part 130 formed by cutting out a part of the flange seat part 13 in the exterior flange part 10 in a moon shape and an engaging part 31 arranged in the mounting hole 30 in the exterior side door plate 3.</p> |
