摘要 |
A blind rivet stem extending through a hollow rivet so that it may be pulled, thereby to expand the tail of the hollow rivet; a collar on the stem has a head fitting in a locking groove within the grip length of the stem so that when the tail of the collar abuts a pressure element bearing against the head of the hollow rivet, it is bulged outwardly into a recess in the rivet head, thereby to interlock the rivet stem and the hollow rivet; a weakened portion such as a break groove is provided on the stem adjacent the bulged end of the collar whereby upon further pulling the rivet breaks at said weakened portion. |