| 摘要 |
A method and apparatus are disclosed for forming blown thermoplastic articles in which an extrusion head extrudes an essentially tubular parison of thermoplastic material. Sections of a preform mold are then closed around the parison, the sections having a preform cavity with a configuration such that one end of the parison is open after closing and the other end is enclosed. A core pin is next inserted into the open end of the parison and is utilized to compression mold the parison to form a preform. Heat is transferred from the parison through the inner and outer walls of the preform between the mold cavity and core pin during the compression molding step in order to thermally condition the preform and bring the temperature within the desired range. The sections of the preform mold are then opened and the preform is enclosed within sections of blow molds within a blow mold cavity. The preform is next expanded to the shape of the blow mold cavity. This process may be continuously repeated by means of multifunction mold halves.
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