US Patent 10252317 Die button

A die button for the punching in and fastening of a fastener element having a piercing section to a planar workpiece, in particular a sheet metal part. The die button includes a jacket. Also included is a die plunger movably arranged in the jacket. Further included is a biasing device for pressing the plunger against the workpiece when the workpiece is supported on the jacket with a pressing force made available by the biasing device and selected such that the die plunger first moves when a slug has been detached from the workpiece by the piercing section of the fastener element.