| 摘要 |
A fastener has a shaft, a head at a first end of the shaft, and a point at the other end of the shaft. A first portion of the shaft adjacent the point is threaded. The first portion typically extends about one-half the total length of the shaft. A second portion of the shaft (adjacent the head) is not threaded, but has a plurality of spaced rings. A knurled portion can be provided between the first and second portions, if desired. Conventional symmetrical or asymmetrical thread can be used in the threaded portion, or a three lobe thread can be used.
|
