| 摘要 |
PURPOSE:To prevent generation of a defective, by pressing so that the surface of a dome part is not flawed. CONSTITUTION:A spherical projecting part of an upper metallic mold is pressed against a material from the tip side, and a dome part is formed on the material. In this case, it is formed so that the dome part does not contact with the inside of the hollowed part of a lower metallic mold. Even in case when there is a vapor-deposited film on one surface of the material, damage of the surface of the dome part is prevented by directing said film to the lower metallic mold side. Also, distortion of the dome part is prevented by placing and supporting the material by the circumferential edge between the upper and lower metallic molds. |
