| 摘要 |
An apparatus and method includes a mold which defines a mold cavity with an inlet through which a molten, moldable material can pass into and/or through the mold cavity. A feeder for preparing the molten, moldable material, is spaced from the mold and expels the material to the mold cavity or to an accumulator connected to the mold cavity. A mechanism for controlling the temperature of the material in the feeder, accumulator, and the mold, as well as at least one gas injection unit with controls for the gas before, during and after its injection into the mold cavity and/or into gas channels located within and/or around the mold cavity are provided. A closed loop regulating system easily adjusts and regulates the gas flow and monitors the average gas pressure of the injected gas according to a programmed conditioning signal. The gas injection unit has relief valves and gas tanks. Also included in the gas injection unit is gas purging/venting equipment capable of producing a vacuum in the mold cavity and/or in the gas channels and/or inducing a differential of pressure creating flow of pressurized gas. Pressure, temperature and vibration probes are located in the mold assembly and in the gas injection unit(s) and are connected to transducers controlled by a computer. A controlled amount of volatile chemicals can be mixed with the inert gas of the gas injection unit. The apparatus includes one or more vibration devices to induce controlled high or low frequency low or high amplitude vibrations in the gas flowing. A mechanism controls the timing of activation of vibration during the filling, packing and cooling stages of the molding operation. |
