| 摘要 |
PROBLEM TO BE SOLVED: To provide a press forming technology capable of realizing the excellent shape accuracy of a product. SOLUTION: The holding force in the initial forming stage is set to be FF1 of a medium value, the holding force in the middle forming stage is set to be FF2 of a small value, and the holding force in the final forming stage is set to be FF3 of a large value, respectively, preventing a product from being in a wrinkle area or a crack area. In the final forming stage, the elongation of a blank is very small, and any crack is not formed even when the holding force is increased. The shape accuracy of the formed product can be enhanced by weakening the holding force of a movable bead in the middle forming stage. COPYRIGHT: (C)2008,JPO&INPIT
|
