| 摘要 |
A resin transfer molding apparatus includes a single-shot metering pump which feeds a predetermined amount of resin material to the mold with a single stroke of the pump via an injector assembly which is mounted on the mold. A closed-loop hydraulic control of the metering pump enables the injection rate and pressure of the resin to be varied during the injection cycle to produce a more consistent fill of the mold and eliminate part waviness caused by pressure rise and fall. The mold-mounted injector assembly and placement of a plurality of valves in the apparatus enables recirculation of unused resin material back to the supply tank at a temperature sufficiently cool to prevent curing, so that solvent flushing of the apparatus can be eliminated in most cases. The apparatus is automatically controlled by a computer resulting in an integrated automatic apparatus. The attached injector assembly and valves also permit automatic switching between different resins by resin or solvent flushing of the lines of the apparatus, which eliminates draining and refilling the apparatus.
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