| 摘要 |
PURPOSE:To form a cylindrical product with high precision, by punch-forming a blank cylindrical material by using a rotary core shaft, and continuing the punch-forming again when the tip of the formed cylinder reaches the coaxial fixed jig, after resetting the tip of a formed cylinder to a fixed jig. CONSTITUTION:A rotary core shaft 1, having a length shorter than that of a product, is fixed to a main body of working machine 2, and a fixed jig 3 is installed coaxially at a distance apart from the shaft 1. The sum of the length of shaft 1 and the length from the tip of shaft 1 to the jig 3 is made equal to the length of a product. A cylindrical blank material 4 is attached to the tip of the shaft 1 and is punch-formed into a cylindrical product 4a by a forming roller 5 and; the tip of the product 4a reaches the jig 3. At this time, the blank material 4 is replaced to be attached to the jig 3 so as to be punch-formed again by the rollers 5. By this way, the final product is formed for the length from the jig 3 to the root of the shaft 1. |
