摘要 |
A shock absorber as being of a bumper supporting member and a shock absorber as being of a side member, which retain the sinking motion of a smaller-diameter tube portion into a larger-diameter tube portion even if an impact is applied at a larger angle obliquely of an axial direction, thereby to achieve the absorption of the impact energy by a plastic deformation. A plastically deformable straight tube is partially reduced or partially enlarged to form a smaller-diameter tube portion and a larger-diameter tube portion, which join to each other through a step portion. The step portion is formed by joining a folded-back portion of the smaller-diameter tube portion and a folded-back portion of the larger-diameter tube portion, which have circular arc-shaped sections having arcuate angles more than 90 degrees.
|