| 摘要 |
<p>A dowel for securing an anchoring bolt in stone etc. has a casing (1) made of sintered metal. It has four slots (2) along one end, about half its length, forming four fingers (1b) which are spread apart by a steel expanding member (4) which can be barrel or cone shaped. The inside surface of each finger is sloping, so that when the expander is forced down, the fingers are expanded outwards against the inside of the hole in the stone. The inside face of each finger can be curved. In one design, the expander has a rounded ridge around the front end, this being forced against the curved inside surfaces (1c). In further designs, each finger carries a groove across its tips into which the ridge locates when pushed forwards.</p> |
