| 摘要 |
PURPOSE:To obtain a molded product having no cracks, by employing a torpedo integrally formed with and frontwardly projected from a breaker plate, whereby torpedo-supporting spokes can be omitted. CONSTITUTION:An electric current is applied to a heater 3 for a cylinder 2 and heaters 8, 9, 10 for a die 6 to heat the cylinder 2, die 6 and a torpedo 17 and thermally melt a synthetic resin moving therebetween. A screw 20 is turned at the same time to extrude a cylindrical molded product from a die section 14 at the front end portion of an extrusion mold 22. Since the torpedo 17 is integrally formed with and frontwardly extended from a breaker plate 16, it is unnecessary to provide the die 6 with torpedo-supporting spokes. Therefore, a homogeneous synthetic resin is extruded from a space around the whole of the circumferential surface of the torpedo 17. Thus, an extrusion-molded product, which is superior in toughness and stiffness to a similar prior art product consisting of the same material, can be obtained. |
