| 摘要 |
An expansion dowel assembly is made up of an anchor bolt and an expansion sleeve laterally enclosing the bolt. The sleeve is expanded by driving it in the axial direction relative to the bolt so that the end of the sleeve widens as it moves axially over a conically shaped expanding member on the bolt. The axially extending surface of the expanding member is formed as a concave surface affording an increasing conicity in the driving direction. Cutting teeth are formed on the outer surface of the sleeve and provide a saw-tooth section. When the sleeve is driven relative to the bolt, the teeth cut into the surface of a borehole in a receiving material and form an undercut in the borehole surface. To facilitate expansion, an annular groove is located in the outside surface of the sleeve adjacent the cutting teeth. The annular groove is located on the opposite side of the cutting teeth from the leading end of the expansion sleeve. |
