摘要 |
A receptacle includes a hollow cylinder and a flange. A plug includes a barrel having a cylindrical body, a semicylindrical section extending from the body, and an engaging section provided at an end of the semicylindrical section and a coupling nut. A boom-like retaining piece is cut out and formed in the semicylindrical section and a retaining hook is formed at an idle end of the retaining piece located in the engaging section. The coupling nut is screwed onto threads of the hollow cylinder so that the plug is connected to the receptacle. Before the connection, the engaging section is engaged with and inserted into the hollow cylinder and the retaining piece is caught in the receptacle, so that the plug is temporarily retained to the receptacle securely. |