| 摘要 |
PURPOSE:To obtain a lightweight inexpensive wheel and simplify a casting mold, by providing respective torque locks on a brake drum and a bearing boss which are welded to each other, and fastening the brake drum to a rim by screws. CONSTITUTION:A brake drum 2 is formed by pressing a steel plate and providing torque lock portions at plural position of the pressed steel plate. A steel pipe is treated by inside and outside diameter finishing to form a boss 1. The boss 1 is fitted in a central portion of the drum 2, and is fixed to the drum 2 at a welding portion. Then, the welded member is die-cast to produce a wheel. At this time, a rim 3 is fastened to the brake drum 2 by screws 11. Further, the rim 3 is formed with a rim torque lock 13. According to this mthod, it is possible to obtain a lightweight inexpensive wheel and simplify a casting mold. |
