Injector for molding hardenable liquid precursors

摘要

An injector is provided for injecting hardenable liquid polymer precursors from an accumulator into a mold in a reaction injection molding process. A specially adapted plunger is employed to eject the liquid precursor from an accumulator barrel. The plunger provides a constant fluid-flow relationship between the liquid precursor inlet and the accumulator barrel during its full stroke. The plunger structure prevents the introduction of air and substantially empties the accumulator on each molding cycle.