| 摘要 |
<p>PROBLEM TO BE SOLVED: To avoid capacity expansion of a fuel tank main body and stress concentration to a welded part at the time of bending processing of a polymerized part of front and rear flanges. SOLUTION: As a bead part 4 is recessively provided on a part corresponding to a belt 7 of a lower shell 3, at the time of forming a run off part 5 of the belt by bending and forming a flange polymerized part 1a at a large bending angle, it is bent with a molding base part of a marginal flange of the lower shell 3 as its base point by recessive provision of the bead part 4, and consequently, it is possible to avoid stress concentration to a welded part by seam welding of the flange piolymerized part 1a. Additionally, it is possible to enlarge capacity of a fuel tank main body 1 as a general surface 6 except for the bead part 4 of the lower shell 3 is formed in conformity with front and rear wall surfaces 2b, 2c of an upper shell 2 at the same level.</p> |
