| 摘要 |
PURPOSE:To provide a high-precise tie bar punch by a method wherein processing of one side end part of a cemented carbide chip, processing of the other side end part effected in succession after a final cutting edge part is formed, and processing of the groove of a comb-teeth-form cutting edge are executed by means of one and the same rotary blade. CONSTITUTION:One side end part 1' of a cemented carbide chip 1 being a material is cut by a rotary blade 5. Consecutively, cutting edge parts 3 are formed at a given pitch on a basis of a cut surface 1a. After a final cutting edge part 3' is formed by the rotary blade 5, the other side end part 1', consecutively, is cut to produce a desired tie bar punch. As noted above, by effecting various kinds of processing by means of the same rotary blade, machining strains are all uniformized and the fall down of the cutting edge part is prevented from occurring. Further, there is no need for registration of the rotary blade with a positioning reference surface, and a high-precise tie bar punch can be produced. |
