Patent ID: 7155798

Claim:
In a method for the attachment of a functional element to a sheet metal part to form a final assembly component, wherein the functional element has an at least substantially non-deformable body section of a larger diameter which merges via a ring-like contact surface into a deformable tubular rivet section of a smaller diameter and also has rib-like features providing security against rotation which are present in raised form in the region of the contact surface and/or at the outer side of the rivet section, a method comprising: pre-holing the sheet metal part to form a right cylindrical hole to receive the rivet section; introducing the rivet section in the hole; reshaping the rivet section radially outwardly to form a rivet bead by means of a riveting die button having a raised portion at its end face confronting the sheet metal; wherein the hole in the sheet metal part is so formed that the sheet metal part lies in one plane in the region confronting the end face of the riveting die button and at least substantially does not project beyond this plane, wherein the hole in the sheet metal part is formed with an inner diameter which is larger by an amount in the range from 0.8 mm to 1.2 mm than an outer diameter of the rivet section, ignoring features present thereon providing security against rotation, whereby a marginal region of the hole is deformed by the action of the riveting die button out of the sheet metal plane and in the direction of the body section of the functional element before the marginal region of the hole enters into contact with the riveting section as a result of the formation of the rivet bead and does not prevent either a bending of the marginal region of the hole out of the sheet metal plane or the formation of the rivet bead and wherein the functional element is placed, for the carrying out of the method, in a recess of a setting head having a free end face so that said contact surface of the functional element does not project at least substantially beyond the free end face of the setting head confronting the sheet metal part and is as a rule set back from this end face.