| 摘要 |
PURPOSE:To secure a proper strength and reduce the whole weight of the captioned apparatus by forming two arm members by bending each plate material and forming an A-figure-shaped suspension lower arm through mutual superposition and welding, in a double wishbone-type suspension apparatus. CONSTITUTION:The first arm member 21 which is equipped with an upper wall part 21a having a concaved part 21i at a part, side wall parts 21b and 21c, horizontal flange parts 21d and 21e, tilt sidewall part 21f, and a flat-plate-shaped extension part 21g is formed by bending a plate material. Similarly, the second arm member 22 which is equipped with an upper wall part 22a, side wall parts 22b and 22c, horizontal flanges 22d and 22e, and a reinforcing wall part 22h is formed by bending a plate material. The second arm member 22 is superposed onto the first arm member 21 at a ball-joint installation part 23 and joined through welding. With such constitution, the joint part is formed into double structure, and the rigidity of the rear side part where strength is necessary is improved because of closed sectional structure, and the front side part where strength is unnecessary is formed into a simple structure and made lightweight. |
