摘要 |
PURPOSE:To obtain a material holding device that holds the end of a material surely without damaging it and facilitates drawing by connecting the material holding part to a wedge-shaped part of a slidable block and providing a stopping part that stops sliding of the block. CONSTITUTION:A material W to be worked is held between blocks 18, 28 that contact with stoppers 25, 35 of an upper die 10 and a lower die 37 respectively. When an inner ram 13 is lowered and a punch 14 pulls the material in the direction of a die 12, tensile force acts on the end of the material. The two blocks, 18, 28, while holding the material W, slide slanting faces 22, 32 to inside of the die until they come into contact with slanting faces 23, 34 of plates 17, 27 guided by slide planes 24, 33 of guide plates 17, 27 corresponding to slide planes 19, 29. Under this condition, the material W is drawn in the direction of the die 12. At this time, since wedge action operates between the slanting faces 22, 32 and corresponding slanting faces 23, 34, large holding force is applied to the material W, and the end of the material W is made to a nearly fixed state. Thus, it can be stretched by the punch 14 that continues to descend further. |