Verfahren und Vorrichtung zum Spritzpressen von faserverstärkten Kunststoffen

摘要

Fibers are added to the plastic and are mixed in by an extruder screw (9). Plasticized material then flows along a straight path on the central axis (13) of the plasticizing unit (2), the injection unit (3) and injection nozzle (50) into the tool. An Independent claim is included for a molding apparatus whose plasticizing extruder (2), injection unit (3) including injection cylinder (32), piston (38) and nozzle (50) lie behind each other on the common central axis and a central bore (42) through the injection unit enables material to be pumped to the tool cavity. Preferred Features: Plastic is compressed before adding cut fibers in a decompression zone of the plasticizing unit. The filled material is then recompressed. The conveying path for the fiber-filled material is free from obstruction or dead spots. Two plasticizing and injection units may be used, one on each side of the mold. Glass-filled material is injected through a slit die into the mold.