| 摘要 |
<p>An object is to make it possible to manufacture, with high dimensional precision, a press-formed curved closed-structure part that has a curved surface in a bottom portion thereof while reducing the manufacturing cost by reducing the number of forming steps and the number of dies. Provided is a method for manufacturing a closed-structure part by forming a flat plate-shaped workpiece B into a closed structure including a bottom portion B1 that is curved along a longitudinal direction. The method includes a first forming step of forming a plurality of first out-of-plane deformed portions 10 and a bent portion B4, the first out-of-plane deformed portions 10 being formed at least in a region of the workpiece B corresponding to the bottom portion B1 and arranged along the longitudinal direction, each of the out-of-plane deformed portions having a recessed shape or a protruding shape; and a second forming step of squashing the first out-of-plane deformed portions 10 between a pad 4 and a punch 3 and bending bent portions B4 by pressing the punch 3 into a space between dies 5 while the region of the workpiece B corresponding to the bottom portion B1 is clamped between the pad 4 and the punch 3.</p> |
