摘要 |
This disclosure relates to both a method and apparatus for forming injection molded articles in a molding assembly which includes a heated runner housing adjacent a cooled mold. In a first disclosed embodiment, a slidable gate valve having a supply passageway is interposed between and in contact with both the cooled mold and heated runner. A layer of insulation material is included on the slidable gate valve to thermally segregate the differential temperature zones of the mold and runner. In a second embodiment, an axially reciprocable pin valve selectively opens and closes a passageway between a heated runner housing and a cooled mold to regulate the flow of plastic material. An annular sleeve of insulation material is telescoped over a portion of the pin valve to likewise thermally segregate the runner and mold.
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