| 摘要 |
A plastics material expansion dowel has an axially extending dowel body with a central hole extending in its axial direction and with wave-form slots also extending in the axial direction and opening into the central hole. The wave-form slots have alternating crests and troughs. The width being greatest at the top of the crests and the bottom of the troughs and being least at the transition between the crests and the troughs. A spreading screw can be inserted into the central hole for effecting the expansion of the dowel body. The number of wave crests exceeds the number of wave troughs in the screw-in direction of the spreading screw by one. Further, the outside surface of the dowel body has axially spaced groove-like recesses extending in the circumferential direction for affording surface profiling. |
