IN PROCESS MATERIAL PROPERTY CONTROL TECHNIQUE

摘要

A process and apparatus for applying an oscillating force to a molten material. The apparatus includes a barrel in communication with a hopper for receiving a flow of moldable material. A screw conveyor is rotatable and axially reciprocatable within the barrel. At least one conveyor flight is formed on the screw conveyor for conveying and compressing the moldable material. Rotation and reciprocation of the screw conveyor forces the material to flow out of the barrel and along a conduit in a mold assembly. The conduit communicates with a mold cavity. A controller controls the rotation and reciprocation of the screw conveyor. The controller reciprocates the screw conveyor toward and away from the mold during filling of the mold cavity inducing a shearing of the material. Each reciprocation of the screw conveyor translates the screw conveyor closer toward the mold cavity. A method is also disclosed which includes dispensing a moldable material into an barrel. Rotating a screw conveyor about its longitudinal axis for conveying the moldable material. Accumulating a predetermined amount of material. Translating the screw conveyor along its longitudinal axis toward a mold to a first location, thereby forcing a portion of the accumulated material to flow into a mold cavity. Translating the screw conveyor away from the mold. Then translating the screw conveyor again toward the mold to a second location, thereby forcing additional accumulated material to flow into the mold cavity, the second location being closer to the mold than the first location.