| 摘要 |
PURPOSE:To execute cold forming to hollow and cylindrical high-accuracy product slag, by squeezing the outside circumference by a hollow die, a pressure punch and a counter punch with respect to semifinished slag whose outside circumference is like a barrel, and simultaneously, compressing the upper and lower end faces. CONSTITUTION:Slag semifinished goods 12 are placed on a counter punch 18 floated by a spring of a forming device 15. Subsequently, by a pressure punch 17 fitted to a hollow die 16, the slag semifinished goods 12 are pushed into the hollow die 16. As a result, the slag semifinished goods 12 are guided and centered by an inlet 23 of a tapered part, a barrellike outside circumferential part 11 is squeezed by a circlar arc part 24 whose inside diameter is smaller than said part, and it is formed to a prescribed exact outside diameter size. When the pressure punch 17 is further pushed in, both its end faces are compressed by the pressure punch 17 and the counter punch 18. In this way, it is possible to obtain a product slag having high accuracy, which has high outside diameter size, and is formed with high accuracy with respect to a parallel degree and flatness of both end faces 1, 3, and perpendicularity of each end face and the outside circumference. |
