| 摘要 |
1,218,373. Fasteners. HILTI A.G. 15 Oct., 1968 [2 Nov., 1967], No. 48730/68. Heading F2H. In a fastener, such as a bolt or nail, having a head 2, shank 3 and tip 5 and provided with a collar 4 on the shank 3 for driving by means of a plunger of a power operated tool 22 into iron or concrete 25, the collar 4 is disposed on the shank 3 adjacent the tip 5 and at least part of the shank 3 between the collar 4 and the head 2 is resiliently flexible. |
