| 摘要 |
A fastener mandrel (20) has formed on one end a shoulder (42) and a twisted, generally rectangular shaped head (40) adjoining the shoulder. In setting the fastener in a workpiece, the shoulder enlarges the end of a tubular rivet (22) and clamps workpieces together in combination with a preformed head (26) on the other end of the rivet (22). The mandrel head (40) deforms the rivet tail (28) into a twisted appearing shape with a somewhat elliptical cross section that partially encloses the mandrel head (40) to provide good stem retention and prevent axial looseness. A plurality of axial ribs (48) on the mandrel stem (38) are drawn into a reduced diameter section of the rivet head end when the rivet is set, thereby providing additional stem retention and torsional interference. |
