| 摘要 |
PROBLEM TO BE SOLVED: To simply, rapidly facilitate color change, resin replacement and to eliminate a linear generation of different colors or resins in a molding by shortening a resin route from an end of a screw to a resin outlet of a parison extruder for rotating longitudinal cone type screw through a reduction gear by a variable speed motor. SOLUTION: A conical type screw of a longitudinal extruder is rotatably brought into contact with a barrel contained in a cylinder, formed in a truncated conical shape to accelerate a flowing speed faster from a large diameter side toward a small-diameter side, thereby enhancing a kneading effect. A breaker plate 39 is provided on the midway of a resin route 38 from an end of the screw to a resin outlet to axially straighten a flow of the resin. The resin supplied by a hopper 43 is extruded to a parison 42 from a gap between a die 40 and a core 41, the resin adhered to a wall surface of the barrel is always scraped by a light of the screw, thereby shortening the route 38 from the end of the screw to the outlet. Thus, the route 38 is short to prevent thermal deterioration of the resin, and rapid resin replacement or color change can be executed without adverse influence to the molding. |
