| 摘要 |
PURPOSE:To enable stable casting even if lower end of brake ring is eroded by arranging lower end of a brake ring as recessing from inner face of upper part of a mold and forming lower end of a vertical hole of the mold fitting to a feed nozzle to a smooth shape broadening downward. CONSTITUTION:The lower end of the brake ring 10 is arranged as recessing from the upper face of inner part of the mold 8. Further, the lower end of the vertical hole 20 arranged at upper part of center of the mold 8 is formed to the smooth shape broadening downward. In the case of satisfying the prescribed conditions to inclining angle theta in the lower end face 22 of the vertical hole 20 of the mold 8 and radiuses R1 and R2 at intersections, even if the lower end of the brake ring 10 is damaged by a little, as the solidified shell developing at fitting part of the brake ring 10 with the mold 8 is smoothly drawn, the unstable casting and local erosion of the mold can be prevented. |
