| 摘要 |
1276998 Pipe joints FORSHEDA GUMMIFABRIK AB 19 April 1971 [2 March 1970] 22700/71 Heading F2G A spigot-and-socket joint having a packing ring 16 of rubber is stiffened by means of a supporting ring 17 which comprises a pair of rings 18, 19 which mutually interact at generally tapered surfaces 20, 21 so that when the inner ring 19 is forced axially into the outer ring 18, the rings press radially against spigot and socket walls 14, 15. In the embodiment shown, the pipe socket and spigot are of cast iron. The outer ring 18 has a flange 24 which abuts the end of the socket 11 and the surfaces 20, 21 have annular ridges of a hook or barb shape (22, 23) (Fig. 2, not shown) to allow easy relative motion of the rings in the direction in which the joint is tightened but relative motion in the opposite direction is resisted. The rings, which are preferably of plastics material, may be split in at least one place to allow them to be opened out and snapped around the pipe spigot prior to insertion into the socket. A tendency for the supporting ring 17 to roll out of the annular space when the joint is simultaneously bent and rolled is inhibited by the frictional engagement of further annular ridges 25 on the outer ring 18 with the socket wall. |
