| 摘要 |
A screw having a polygonal cross section exhibits a threaded section and a forming section adjoining the threaded section and extending as far as a front rounded end of the screw and, if necessary, being free of threads. The lateral line of the forming section, if necessary free of threads, runs smoothly and without interruption from the threaded section as far as the tip at a constant curvature. The screw serves for the attachment of an element to a sheet metal component, whereby said screw engages in an existing hole in the sheet metal component and forms the thread itself. Said screw is thereby also capable of enlarging the hole and forming a raised rim hole. |
