Hydroforming apparatus for metal plate, hydroforming method therefor, and molded product using them

摘要

PPROBLEM TO BE SOLVED: To provide a hydroform apparatus for a metallic sheet and a hydroform process therefor by which any crack or wrinkle is not caused even when forming a formed article having high strength and complicated shape. PSOLUTION: The hydroform apparatus has an upper die having a cavity shaped to the same inner shell with all the formed articles, and a blank holder surface disposed on its peripheral edge, a lower die provide with the blank holder surface and holding the metallic sheet by facing the cavity, a means for introducing a forming medium between the metallic plate and the lower die, and a draw bead comprising a seal ring groove mounting a seal ring over the entire circumference of the blank holder surface of the lower die, a bead groove disposed on the blank holder surface of the upper die or the lower die, and a bead peak disposed on blank holder surface of the upper die or the lower die so as to fit into the bead groove, in which a forming medium is introduced into the cavity of the upper die by driving the introducing means and the metallic sheet is bulged along the cavity. PCOPYRIGHT: (C)2007,JPO&INPIT