| 摘要 |
PURPOSE:To obtain a punching device at a low cost by discontinuing the use of a collar which is used for preventing a punch from falling out. CONSTITUTION:When a plate material 10 is placed on a die 8, and an upper die substrate 1 is made to descend, a lower face 5b of a holding plate 5 fixes the plate material 10 onto the die 8, a pressure plate 6 pushes an upper end face of a punch 7 and the punch 7 descends. A pressure receiving surface 7c of the punch 7 depresses a bearing surface 3c of a punch supporting plate 3 against a spring 4 and punches the plate material 10. When the upper die substrate 1 ascends, the spring 4 pushes up the punch supporting plate 3, and simultaneously, and the punch 7 is also pushed up the bearing surface 3c of the punch supporting plate 3 and the punch 7 is drawn out of the plate material 10. A force of the time when the punch 7 is drawn out of the plate material 10 is mainly applied to the bearing surface 3c and the pressure receiving surface 7c, therefore, it does not occur that the punch 7 falls out downward. In this way, a collar formed in a conventional punch becomes unnecessary, the more the punch 7 is, the less expensive it becomes. |
