| 摘要 |
PURPOSE:To take out a green compact having chamfering part without any damages of the green compact and a punch by promoting expansion of the green compact while descending a lower die after compacting, taking out the green compact from the die and next, ascending the lower die again. CONSTITUTION:After forming the green compact W1 under compressing, an upper punch 3 is ascended and the lower die 1 is descended to the standard position. In the green compact W1, the chamfering part W2 is formed at outer circumference of lower face by edge part 5 of recessed part 4 in the lower punch 3. Further, the lower die 1 is descended to relax the restriction caused by the die to the chamfering part W2 of the green compact W1. The green compact W1 is expanded toward diameter direction, and lifted upward and removed from the recessed part 4. Next, the lower die 1 is ascended, so that a lower punch 3 is inserted into a cavity 2 and after laying the green compact W1 on the upper face of the lower die 1, the take-out operation is executed. By this method, the yield of the green compact having chamfering part is improved and the service life and durability of the lower punch 3 are improved.
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