Patent ID: 6113331
Filing Date: 2000-09-05
Classification: F16B

Abstract:
Fastening screw (1), formed by cold rolling, with a self-tapping thread (2, 11) for screwing into thermoplastics, and materials which have properties similar to those of thermoplastics with an essentially continuously cylindrical thread bottom (8) and with thread teeth (10) which have a vertex of continuously equal height, the free spaces between adjacent thread teeth (10) being made the same along the thread (2, 11), characterized by the combination of the following features,1. the outside diameter Do and the core diameter Dk of the thread form a quotient Q1=Do/Dk of a magnitude of 1.2 to 1.4;2. the axial spacing P of adjacent thread teeth forms, with the height H of the thread teeth, a quotient Q2=P/H which is between 2.75 and 2.9; and3. the vertex angle of the thread teeth is about 30.degree..