2008 Volume 16 Issue 2 Pages 50-57
This study concems optimization of multicavity injection molding, in which melted resin is filled into each cavity through multiple flow runners that ramify in the mold. Over-filling and under-filling tend to occur due to differences in filling conditions caused by differences in runner length for each cavity, leading to such problems as defective appearance and failure to achieve the intended dimensions. To establish this difficult multicavity injection molding technology,one-by-one problem solving was considered to be limited and inefficient, so this time we utilized quality engineering, which provides more efficient evaluation. Experiments were performed by simulation to analyze the resin flow, and the flow runners were optimized so as to stabilize the filling of each cavity. The improvement achieved in simulation was confirmed by actual injection molding. In the end we succeeded in improving filling conditions and reducing the amount of discarded resin at the same time.
