Patent ID: 7401394

Claim:
Method of joining a in the form of a bolt element, fastener element ( 10 ), having a head portion ( 12 ), a recess ( 20 ) under said head portion, a shaft portion ( 16 ) and at least one radial groove formed as a thread around the shaft portion, to a sheet metal component ( 52 ) by forming a hole in said sheet metal component in such a way that a collar ( 120 ) of material is formed at the side of the sheet metal component remote from the head portion of said fastener element, with the material of said collar ( 120 ) being subsequently deformed radially inwardly into said radial groove ( 28 ) by a die button, wherein a die button is used having a ring-shaped projection provided at its end face surrounding a tapered recess ( 112 ) and having sloping flanks ( 222 , 226 ) for pressing said sheet metal component upwardly into said recess ( 20 ) provided under said head portion ( 12 ) of said fastener element ( 10 ) and radially inwardly towards said shaft portion ( 16 ) into said radial groove ( 28 ) in the transition from said head portion ( 12 ) to said shaft portion ( 16 ).