REACTION INJECTION MOLDING AND ITS DEVICE

摘要

PURPOSE:To manufacture RIM products without shrinkage and fins by injection of resin after providing a packing on the parting face of a mold to reduce pressure in the cavity of the mold. CONSTITUTION:After keeping a cavity C air-tight by providing a packing 11 in the parting face of a cope 2 and drag 3, a vacuum pump 8 is operated to reduce pressure in the cavity C and at the same time a reactive resin is injected from a mixing head 9 into the cavity C. Because it is injected into the cavity that has its pressure reduced. RIM (reaction injection molding) products are obtained that have no voids no fins. Pressure reduction and releasing of the reduced pressure are carried out with the plunger P of an air cylinder 6.