| 摘要 |
<p>An inner die of a molding die includes a core shaft, split dies radially arranged along an outer peripheral surface of the core shaft around an axis of the core shaft, which serves as a center, and a cylindrical set ring arranged below the split dies, the core shaft being inserted through the set ring. An annular engaging surface, which is a tapered surface whose diameter is gradually reduced downward, is formed in an inner peripheral side of an upper end portion of the set ring, and lower end portions of the respective split dies are introduced into, and engaged with the engaging surface. The molding die includes a pressing portion that presses downward upper end portions of the respective split dies introduced into the set ring, so as to move the lower end portions of the respective split dies toward the axis along the engaging surface.</p> |
