| 摘要 |
PURPOSE:To remove easily, exactly and quickly burrs, by punching a work, returning a punched work to a punching hole of a blank material, removing the burrs, and thereafter, separating them from the blank material again. CONSTITUTION:A thin sheet blank material 1 is fed intermittently, and first of all, a shaft hole 4 of a washer 2 is punched by a small diameter punch of a press machine. Subsequently, by an intermittent feed of one or plural steps of the blank material, said shaft hole 4 is carried in between a large-diameter punch 6 of the press machine and a push-back knockout 7, and a washer 2 is punched by the punch 6. In that case, the punch 6, the washer 2 and the knockout 7 lower together, and burrs 8 are formed on the upper part of the outside circumferential edge of the washer 2. When the punch 6 lifts, the knockout 7 lifts as one body with the punch 6 by its elastic force, and fits the washer 2 into its punched hole 9. Subsequently, burrs 5, 8 are removed between buffs 10, 10, and thereafter, they are separated from the base material 1 by a detaching punch 11. |
