| 摘要 |
The invention relates to a screw (1) comprising a threaded shank (2) with a force application point (4) for transmitting torque and a screw tip (6). The threaded shank (2) is composed of a shank core (10) and an automatically thread-forming thread (12). Said thread (12) is embodied as an elevation tha t has a radial height (H), extends across the shank core (10) in the shape of a helical line, and is delimited by two flanks (15, 16) which intersect in an outer thread edge (14). At least in one subarea of the thread (12), said out er thread edge (14) extends in a radial direction at an amplitude (U) like a wa ve between peaks (20) having a height (H) and valleys having a height (h) that is reduced by said amplitude (U). The thread (12) is provided with indentations (24) at least in the area of one of the flanks (15/16) thereof, said indentations (24) interrupting the surface of the flank (15/16) in the regio n of the valleys (22) of the thread edge (14). The outer limit of the indentations (24) is embodied by the thread edge (14). The thread (12) is provided with a specific first acute angle (a) in the peak (20) regions of t he thread edge (14) which are not interrupted by the indentations (24), said acute angle (a) being formed between the flanks (15/16), while being provide d with a second acute angle (a') in the lowest regions of the valleys (22) of the thread edge (14). The first acute angle (a) between the flanks (15, 16) ranges approximately between 30~ and 35~ while the second acute angle (a') ranges between 30~ and a maximum of 58~. |
