Patent ID: 7752879

Claim:
System comprising an apparatus for the attachment of a fastener element ( 12 ; 12 ′) to a sheet metal part ( 13 ) having a pre-formed hole and a ring collar ( 35 ) surrounding said pre-formed hole, wherein the fastener element has an axis of symmetry ( 18 ), a head part ( 14 ) having a contact surface ( 22 ) which enters into contact with the sheet metal part ( 13 ), a fastening section having a thread ( 15 ; 15 ′) and also at least one undercut ( 24 ; 82 ) which receives the material of the sheet metal part, with the thread ( 15 ) being formed at a shaft part ( 16 ) of the fastener element and wherein the shaft part ( 16 ) can be guided through the pre-formed hole of the sheet metal part, wherein the material of the sheet metal part can he pressed against the contact surface and into the undercut by means of a first tool ( 26 ′) and a second tool ( 62 ), said first tool having a die button shape, a first aperture accommodating said shaft part with clearance and a central ring projection ( 36 ) with an at least substantially conical inner surface ( 38 ) adapted to press the material of said ring collar ( 35 ) radially inwardly into the undercut ( 24 ), said second tool ( 62 ) having a cut-out ( 60 ) receiving said head part ( 14 ) of said fastener element ( 12 ), an end face ( 64 ) which supports the sheet metal part ( 13 ) at least substantially at least at the level of said contact surface ( 22 ) wherein the apparatus has a device generating a force adapted to exert a local force (K) onto said first tool ( 26 ′) to the side of the axis of symmetry ( 18 ) and to move this local force circularly around the axis of symmetry (arrow 43 ) while simultaneously carrying out a relative feed movement (arrow 28 ) between said first tool ( 26 ′) and the fastener element ( 12 ; 12 ′) between which the sheet metal part ( 13 ) is arranged and wherein the local force (K) can be exerted onto the sheet metal part ( 13 ), with the first tool ( 26 ′) which is disposed at an inclined position ( 42 , 42 ′) relative to the axis of symmetry ( 18 ) and being rotatable about the axis of symmetry in order to press the material of the sheet metal part onto the contact surface and into the undercut ( 24 ; 82 ) while said fastener element ( 12 , 12 ′) is supported in said second tool ( 62 ).