Patent ID: 8763233

Claim:
A punch rivet for connecting two workpieces, the rivet comprising a head and a hollow shank open at a first end, the shank defining a shank internal diameter (D 3 ), a shank external diameter (D 1 ) and including at the first end an annular cutting edge defining a cutting edge diameter (D 4 ) smaller than the shank external diameter (D 1 ), and the shank internal diameter (D 3 ) merges with the annular cutting edge via a cutting edge radius (R 2 ), and the ratio of the cutting edge radius (R 2 ) to the shank external diameter (D 1 ) is greater than 0.5 and less than 0.7; and the annular cutting edge merges with the shank external diameter (D 1 ) via a shank outer chamfer which is oriented at a chamfer angle (α 1 ) of less than 42° in relation to a radial plane.