| 摘要 |
A pierce nut (1) for attachment to a plastically deformable metal sheet (4) has an abutment surface (14) adapted to abut against the metal sheet (4), an undercut pilot (11) protruding relatively to the abutment surface (14), and a countersunk groove (16a, 16b) which is formed in the abutment surface (14) and at least partly surrounds the pilot (11). The groove (16a, 16b) is without active undercuts facing the pilot (11). The groove comprises an inner groove (16a) and an outer groove (16b) and a ridge (17) located therebetween. |
