| 摘要 |
PURPOSE:To obtain easily a punched forging having high precision and high quality in a coiling stage wherein a hot striken forging is subjected to setting of the shape while cold by subjecting said forging to punching simultaneously with coining. CONSTITUTION:A forging 19 in a cooled state after it is subjected to striking, a heat treatment, etc. is set in the impression part of a die 11. When the descending of a ram 20 is started by a hydraulic pressure or the like, a punch 10 descends as well and the forging 19 is sandwiched between the punch 10 and the die 11, and the punch 10 and die 11 descend integrally against the repulsive force of a compression spring 16. At the same time, a punching pin 13 projects from the impression part 11a and punches the forging 19 while the punch moves until the rear of the die 11 contacts with a bolster 14. The coining of the forging 19 is accomplished as the ram descends further down to the bottom dead point after the rear of the die 11 contacts with the bolster 14. |
