Image Number 6 for United States Patent #6536936.
A mix head assembly for a rapid discharge multiple material delivery molding system includes an output chamber assembly having a plurality of impellers, a main body assembly, and a drive assembly. The main body assembly preferably includes a plurality of input ports which correspond to the number of fluid material supplies. In one disclosed embodiment, the mix head assembly include a flush assembly to communicate a flushing fluid from a supply through the gates and into the feed chambers to minimize residual fluid material after each molding cycle. In operation, the fluid materials are directed by their respective input ports to a first impeller. The first impeller is driven by the drive shaft such that the impeller drives the fluid materials back toward the input ports. The pressure in the material builds up and it eventually is driven back past the first impeller. Highly effective mixing of the fluid materials is provided as the fluid materials are driven back into the streams of fluid materials from the input ports. The next impeller which the fluid material flow encounters preferably has an opposite pitch such that the second impeller drives the fluid material toward a third impeller. Sequentially alternating between this "with stream" and "against stream" impeller drive orientation preferably continues until the final impeller drives the fluid materials out through a first chamber portion where dividers provide a final fluid material flow disturbance as the fluid material is directed to the mold assembly.