INJECTION MOLDING ALIGNMENT STEERING UTILIZING SEQUENTIAL THROTTLES IN A BASE-WALL-SECTION FLOW GUIDES

摘要

During injection molding of a plastic product having a base wall and a sidewall, alignment of the mold parts that shape the mold cavity is maintained by conducting injected plastic material through a sequence of variable-opening throttles i n a base-wall- section flow guide of the mold cavity. The openings of the throttles vary in response to variations in the thickness of a region of the sidewall section into which injected plastic material is conducted from the base-wall-section flow guide so that upon an increase in the thickness of such region the openings of the throttles in the base-wall- section flow guide decrease and so that upon a decrease in the thickness of such region t he openings of the throttles in the base-wall-section flow guide increase.