| 摘要 |
A self-drilling fastener for attaching wood substrates to metal substrate s comprises an elongate shank defining an axis, the shank having a first end a nd a second end. A drilling tip having a drill point and an axial length is formed at th e first end. A broad head is formed at the second end. The shank includes a threaded portio n and an unthreaded portion. The threaded portion axially extends from the drilling t ip towards the head and includes helical threads and has an axial length, a root diameter, and a thread diameter. The length of the threaded portion is greater than the leng th of the drilling tip. The unthreaded portion axially extends from the threaded porti on to the head and has an axial length and a diameter. The length of the unthreaded portion is substantially greater than the length of the threaded portion and the diamet er of the unthreaded portion is smaller than the thread diameter of the threaded portion. |
