| 摘要 |
A fastener comprises a pin having a head 14 and swaging grooves 16 on its shank, together with a collar 12 which is swaged into the groove 16 to lock the collar to the pin and thereby secure together two metal sheets 23, 24. The underhead face of the pin head is formed with a projecting annular rib 28. When the pin head is urged towards the adjacent sheet 24 during the fastener installation process, the rib 28 enters the sheet 24 and engages therewith. This enhances resistance to relative slipping of the sheet 24 with respect to the pin and the other sheet 23, thereby enabling the use of an oversize hole 26 in the sheet 24. The collar 12 may alternatively or additionally be provided with a similar rib 29 for a similar purpose (Figure 1). <IMAGE> |
