Self-piercing rivet fastening device

A rivet fastening system used to feed and fasten a cylindrical rivet fed from a source, the rivet fastening system comprising:

• a receiver defining an axial an axial through passage and operable for accepting the rivet fed radially onto the through passage from the source;
• a punch holder connected to a first axal side of the receiver;
• a punch supported and axially aligned by the punch holder and operable for axial movement within the through passage;
• a nosepiece connected to a second axal side of the receiver;
• a collet located within the nosepiece and coaxially aligned with the through passage and the nosepiece, the collet including a wall having a first end proximal to the receiver and a second end distal from the receiver, the wall partially defining an axial through bore open at the first end and the second end, and the wall including:
• an inlet portion axially proximal to the receiver;
• a first feeding portion connected to the inlet unit axially opposite to the receiver;
• a second feeding potion connected to the first feeding portion axially opposite to the inlet portion;
• an outlet potion connected to the second feeding portion axially opposite to the first feeding portion;
• at least two of a first slot partially defined by the wall, the first slots radially opposite to each other and axially extending through the inlet portion and into first feeding portion from a first open end at the first end of the collet to a first closed end at a first length;
• a number of a second slot greater than the number of the first slots, the second slots partially defined by the wall, the second slots axially extending through the outlet portion and into the second feeding portion from a second open end at the second end of the collet to a second closed end at a second length;
• and
• when the rivet is fed from the inlet portion and enters the first feeding portion the second slots are closed by the opening of the first slots.