| 摘要 |
Nail-type fastener comprising an elongated shank (1) having three symmetrically positioned, longitudinal grooves (4) separated by longitudinal ridges (8) with a cross-sectional arcuate outer side (9), the grooves having flat, concave or cross-sectional V-shaped bottom surfaces (27, 17, 7). The nail has a high-flexured rigidity and high pull grip with comparatively low weight. The fastener or nail is produced starting from a cross-sectional circular nail wire stock which is profiled in two cold-rolling steps. In the first step, the nail wire passes through a first roller trio, the section rollers producing grooves into the nail wire stock. In the second step, the nail wire passes through a second roller trio, whereby a deepening of these grooves into deep grooves is brought about. Thereupon the head and the point are produced at the ends of the shank, the finished nail thereby being separated. |
