Patent ID: 7377021

Claim:
A method for joining at least a first component and a second component, comprising: arranging the first component to at least partially overlap the second component between an axially moveable upper tool and a lower tool with a flat surface, at least a portion of which is directly beneath the upper tool so that the portion of the flat surface of the lower tool which is directly beneath the upper tool abuts the second component; and after the first component and the second component are arranged between the upper tool and the lower tool with the portion of the flat surface of the lower tool which is directly beneath the upper tool abutting the second component, then maintaining said portion of the flat surface bearing against the second component while pressing an auxiliary joining element with the upper tool axially into the first component to a sufficient extent and with sufficient force to deform the first component, the second component, and the auxiliary joining element plastically between the upper tool and the flat surface enough to cause the first component to extend axially into the second component and then spread radially into a portion of the second component to form an undercut of the first component in the second component and thereby join the first component and the second component in inseparable relation to each other.