Punch rivet and method for the attachment of individual components to one another of which at least one component is formed by a workpiece of composite material
View Patent ↗A punch rivet for fastening individual components to one another of which at least one component is formed by a workpiece, with the punch rivet having a flange of larger diameter, a rivet section of smaller diameter and a ring-like component contact surface at the side of the flange adjacent the rivet section and surrounding the rivet section, with the rivet section having at its free end a ring surface for the piercing of the two workpieces which stands at least substantially perpendicular to the central longitudinal axis of the punch rivet and an inner concave ring surface which forms the transition from the end of the punch rivet into the hollow internal space of the rivet section. Ribs extending parallel to the longitudinal axis are provided at the generally cylindrical outer surface of the rivet section and extend up to the free end face of the rivet section.
1. A method of attaching individual components ( 40 , 42 ) to one another using a punching rivet ( 10 ) wherein at least one of the components ( 40 ) is formed by a workpiece of composite material, with the punch rivet having a flange ( 12 ) of larger diameter (D 1 ), a rivet section ( 14 ) of smaller diameter (D 2 ) and a ring-like component contact surface ( 18 ) at the side ( 16 ) of the flange adjacent the rivet section and surrounding the rivet section, with the rivet section ( 14 ) being designed at its free end ( 22 ) for the piercing of the two workpieces and ribs ( 30 ) extending parallel to the longitudinal axis are provided at the generally right cylindrical outer surface of the rivet section ( 14 ), all of the ribs extending completely to the free end ( 22 ) of the rivet section, with the method including the following steps:
a) arrangement of a first die button against one ( 42 ) of the components ( 40 , 42 ) which are to be secured to one another and which are placed on one another, with the first die button having a bore ( 52 ) which is dimensioned to receive the rivet section ( 14 ) but not however the ribs ( 30 ),
b) carrying out a relative movement of the punch rivet ( 10 ) with the free end ( 22 ) of the rivet section to the fore against the components ( 40 , 42 ) arranged on one another and in the direction of the first die button ( 50 ),
c) piercing of the components ( 40 , 42 ) with the free end ( 22 ) of the rivet section ( 14 ) and introduction of the rivet section into the bore ( 52 ) of the first die button with simultaneous shaving of the material of the ribs ( 30 ) until the component contact surface ( 18 ) comes into contact with the component ( 40 ) adjacent the flange ( 12 ) and the shaved material forms material accumulations ( 36 ) which clamp the components ( 40 , 42 ) between the flange ( 12 ) and the material accumulations.
2. A method in accordance with claim 1 , with further method step
d) that by using a second die button ( 70 ) with a central post ( 72 ) and a concavely rounded ring surface ( 74 ) surrounding the central post, the end ( 37 ) of the rivet section ( 14 ) remote from the flange ( 12 ) projecting out of the components is beaded over to form a rivet bead ( 38 ).
3. A method in accordance with claim 2 , wherein a further pre-pierced component is positioned onto the end ( 37 ) of the rivet section ( 14 ) remote from the flange ( 12 ) and projecting out of the components before the end of the rivet section is beaded over to form a rivet bead ( 38 ).
4. A method in accordance with claim 1 , wherein the piercing slugs ( 54 ) which arise in the steps b) and c) are either disposed of through the diverging bore ( 52 ) of the first die button ( 50 ) or are moved by a central part of the first die button formed as a displaceable plunger into the hollow rivet section ( 14 ).