摘要 |
The sheet metal blank to be press molded comprises a product section (W1) and a grip section (W2) disposed on the periphery of the product section (W1). The press molding device performs press molding on the product section (W1) while gripping the grip section (W2) with the upper die (11) and the lower die (12). A bead (W3) comprising alternately disposed indented sections (A, C) and protruding sections (B, D) is press molded beforehand on the grip section (W2) by meshing the indented corners (6, 8) and protruding corners (3, 5) formed on the lower die (12) with corresponding indented corners (7, 9) and protruding corners (2, 4) formed on the upper die (11). Consequently a preferable constraining force without reducing the radius of the indented sections (A, C) and protruding sections (B, D), thereby protecting the galvanized surface of the sheet blank from chipping. |