Patent ID: 6904831

Claim:
A rivet setting device for setting a self-tapping rivet of the type having a hollow rivet body and a mandrel disposed longitudinally within the hollow rivet body, the mandrel including a self-tapping head for forming a hole in a work piece and radially compressing and spreading the rivet body as the mandrel is retracted rearward relative to the rivet body and a shank having an area of reduced diameter for allowing the head to detach from the shank upon application of predetermined tensile force applied to the shank, the rivet setting device comprising: a clutch for gripping and turning the shank, the clutch including a body having an aperture for receiving the shank, for rotating self-tapping head to form a hole in a workpiece; and a shank retracting assembly for retracting the shank rearward relative to the rivet body for compressing and spreading the rivet body and thereafter separating the shank at the area of reduced diameter, wherein the body includes a tapered channel for urging the bearing into engagement with the shank upon rotation of the clutch, the tapered channel narrows from a region of large cross-sectional area to a region of small cross-sectional area counter to a direction of rotation of the self-tapping head.