Functional element, a component assembly consisting of a functional element and a sheet metal part and also a method for the attachment of the functional element to a sheet metal part

A functional element (10′;

• 10″) having a functional portion (16;
• 17;
• 17′), a generally tubular rivet portion with a free end (59) and an annular sheet metal contact surface (22;
• 22′;
• 22″;
• 22″, 22′″, 22″″), wherein the tubular rivet portion has a cylindrical surface and is adapted to be turned over radially outwardly to form an annular rivet bead having a U-shape in cross section, the tubular rivet portion having features of shape (70;
• 70, 70′;
• 80;
• 80, 70;
• 90;
• 90, 70) provided at the tubular rivet portion (20) and adapted to generate co-movement of a sheet metal part (14) during the formation of the rivet bead, the features of shape being provided at least one of the free end (59) of the rivet portion and at the radially outer side of the cylindrical surface of the rivet portion (20) adjacent to and extending up to at least shortly before the free end of the rivet portion.