| 摘要 |
PURPOSE:To enable the installation of a base to an extrusion machine even when the cross section of the molding is large as no projection exists on the back surface of the base and to avoid any trouble even in case of double extrusion molding by supporting an inner part of the die for molding a hollow part of the molding against an outer part of the die through a number of connecting parts radially formed between them. CONSTITUTION:The first base 1 has a circular gap 8 for extruding a material of the inner circumference. An inner die part 9 for forming a hollow part of a molding and an outer die part 10 are thereby separated and the former 9 is supported against the latter 10 by connecting parts 11 radially formed in the circular gap 8. The connecting parts have a rhombic cross section and are set at the position close to the back surface of the base not to disturb the flow of the material. A thin cylindrical wall 12 exists on the outer circumference of the circular gap 8. A circular gap 13 for extruding a material of the outer circumference is formed by the surface of the outer circumference of the thin cylindrical wall and the surface of the inner circumference of the circular opening 3 of the second base 2. |
