| 摘要 |
PROBLEM TO BE SOLVED: To provide a press-forming method of a metal sheet excellent in shape fixability and an apparatus therefor by means of which press-formed goods are obtained without generating a three-dimensional defective shape such as an angle change and the warp (surface warp) on a ridge line and twist due to springback. SOLUTION: In a press-forming method by which the metal sheet is formed by relative straight movement of a die and a punch, the intermediate of the metal sheet on which a plurality of embossments are arranged in the part to be a stretched flange forming region is formed. When press-forming the intermediate, by crushing these embossments with an embossment crushing punch before the bottom dead center of the last stage of the press, imparting compressive stress to the stretch flange forming region and forming a plurality of excess metal beads with an excess metal bead forming punch to the part to be the shrink flange forming region before the bottom dead center of the last stage of the press and imparting tensile stress to the shrink flange forming region, the residual stress of the press-formed goods is leveled. COPYRIGHT: (C)2010,JPO&INPIT |
