| 摘要 |
An expansion dowel includes an axially extending expansion sleeve and an expansion member rolled from a section of sheet metal. The sleeve has a leading end and a trailing end and the inside surface of the sleeve is threaded for an axially extending section from the trailing end. The thread is formed before the sheet metal is rolled. To assure there is no misalignment of the thread along the butt joint, tangs and recesses are formed along the edges of the butt joint so that the edges interengage one another when the sheet metal section is rolled. By interengaging the butt joint edges, the sleeve does not expand circumferentially when a bolt is threaded into the trailing end of the sleeve. |
