| 摘要 |
1495645 Screw sockets P TOPHOLM 5 Feb 1975 [6 Feb 1974] 4842/75 Heading F2H An expansible screw socket 1 is a one-piece plastics moulding comprising a tubular body with an internally threaded portion 4 at one end and a head flange 6 at the other end, with sharp-edged longitudinal ribs 7 under the head flange 6, a respective longitudinal slot 2 aligned with each rib 7 extending from the rib to the screw-threaded portion 4 to divide the main body of the socket into a set of flexible longitudinal strips 3. The ribs 7 stiffen the socket portion next to the head 6 to prevent it from being axially compressed and radially expanded when the slotted portion is axially compressed and radially expanded by tightening of a screw (5) (Figs. 4-7, not shown) engaging the threaded portion 4, to prevent damage to the wall surface about a hole in which the socket is being secured. Each strip 3 has at least one longitudinal rib 8 on its radially outer surface, and is of generally triangular cross-section. The slots 2 are tapered off at the end adjacent the threaded portion 4. |
