Injection molding apparatus and a method therefor

摘要

There is provided an infection molding apparatus capable of preventing an occurrence of over-packing which is comprised of: a pair of dies for forming a plurality of cavities therebetween; die closing devices for closing the pair of dies under a prescribed pressure; an injection device for Injecting a molten resin into respective cavities under a prescribed pressure; and a control device for controlling the die closing devices and the Injection device, and further the apparatus comprises a plurality of pressure sensors for detecting respective pressures in respective cavities, wherein the control device controls the injection device and/or the die closing devices to reduce a rate of injection of the molten resin and/or a force of closing of the dies, otherwise to stop the injection and/or the die closing operation when a pressure difference between cavities is found to be greater than a prescribed value on the basis of sensed values from the respective pressure sensors.