| 摘要 |
A thread-cutting tool comprises a shank 10 for attachment to the spindle of a milling machine, the forward end portion of which shank is formed with a flat 12 recessed to provide a pocket for a flat cutting insert 11. The insert, which is triangular in this instance, has one edge formed with a line of threadform teeth of identical profile. The teeth project laterally for cutting engagement with a work-piece. The surface of the work-piece which is to be formed with a thread is mounted on a fixed work-table of the machine. The tool is rotated about the spindle axis and is simultaneously moved by the spindle in a path centered on the axis of the surface of the work-piece to bring the teeth of the insert into engagement with the surface and the spindle and tool are moved axially continuously by a distance equal to one thread pitch for each revolution of the tool in the circular path, so in one revolution of the tool in the path a number of complete turns of the screw-thread are formed equal to the number of teeth of the insert in engagement with the work-piece. |
