| 摘要 |
PURPOSE:To improve the flow of a blank material toward a cylinder wall, and to reduce a drawing force, by providing plural cylinder devices acting horizontally and radially toward the center from the outside of a die, and pressing the flange part of a blank material by the pushing plates fixed to piston rods. CONSTITUTION:A circular blank material 5 is put on a punch 2, and an upper die is lowered to hold the material 5 by a desired pressure with the aids of a die 6 together with a blank holder 3. Next, pushing plates 11 are intruded into the space between the die 6 and the holder 3 through pistons 10 to press the outer peripheral part of the material 5 by a desired pressure by actuating cylinders 9. At the same time, the die 6 descends continuingly to deep-draw the material 5 in corporation with the punch 2, thereby the cylinder wall part 7 is formed continuingly. At this time, as the flange part of the material 5 is pressed by the plates 11, the flow of material from the flange part 8 toward the cylinder wall part 7 is improved. Moreover, the drawing force can be reduced by the aid of the force energized by the plates 11. |
