A tube coupling

摘要

A tube coupling, including a tubular housing (131), a seal (137) within the housing (131) for sealing against the outside of a tube which is inserted into the coupling, a substantially annular and resilient grab ring (132) located within the housing (131) for gripping the outside of a tube which is inserted into the coupling to retain the tube against release from the coupling. The grab ring (132) is mounted within housing between a first pair of radially inwardly extending abutments which are spaced apart axially in the direction of insertion of a tube into the coupling. A demount member (133) for releasing the grab ring (132) from a condition of gripping the outside of a tube which is inserted into the coupling. The demount member (133) is at least partially within the housing (131) the demount member (133) including a grab ring engaging section and a drive section. The drive section is drivable to shift the engaging section into engagement with the grab ring (132) one or more cams (154) being provided projecting from the housing (131) for engagement by a tool. Cooperation between the tool and the one or more cams (154) is such that rotation of the tool relative to the coupling causes the tool to shift axially to drive the drive section of the demount member to shift the engaging section into engagement with the grab ring (132).