2023 Volume 64 Issue 744 Pages 7-12
The appearance of an automobile is one of the appealing points to customers. Character lines in outer panels such as hood and door panels play an important role in making automobiles attractive, and a sharp character line with a ridge of small curvature radius is much more preferred to a blunt character line. However, a skid line, a type of cosmetic defect, is apt to be generated along the character line during the press forming of a sharp character line. The authors revealed the mechanism of skid line generation by finite element analysis, and reported the results in a previous paper. In this study, a method is developed to continuously measure the panel shape during press forming. The results of the shape measurement suggest that a convex shape formed on the die ridge should move to a flat area of the die that a wavy shape should generate there immediately before the convex shape is flattened at the bottom dead center and that the wavy shape should grow to a skid line through springback.
