Material-displacing, thread-forming screw has cutting section formed from two truncated cone shaped sub-sections which widen in direction of head and which abut directly with each other and merge smoothly into each other

摘要

The material-displacing, thread-forming screw has a cutting section (4) formed from two truncated cone shaped sub-sections which widen in the direction of the head (1) and which abut directly with each other and merge smoothly into each other. The cone angle (alpha ) of the first section (6), which adjoins the cutting point (5), is larger than the cone angle of the second section (7), which adjoins the threaded section (3). The cone angle of the first sub-section is between 20 and 40 degrees, and the cone angle (beta ) of the second sub-section is 15 to 30 degrees.