| 摘要 |
A fixing arrangement comprises a retaining element (2) and a clamping sleeve (3) which receives a bone screw (1). The bone screw has a head (13) and a secondary thread (12) and is pivotally mounted in the clamping sleeve. The clamping sleeve has a radially protruding section (34) on the outer casing (30) of the clamping sleeve and at least one track of a clamping thread (32), which complements the secondary thread, in the interior (31) of the clamping sleeve. In the unclamped state, a free path is formed by a clearance on the clamping sleeve. A protruding section (34) is provided which engages into an opening (24) on the receiving seat (23) in a formfitting manner, and the thickened section (15) is shaped so as to expand towards the rear in the form of a cone. The cone angle (3) is selected such that the free path divided by the tangent of the half-cone angle (tan ß/2) corresponds to 0.5 to 2.5 times the thread pitch (h) of the secondary thread. By means of the cone angle selected in this manner, the clearance disappears after tightening by a specified tightening angle. |
