| 摘要 |
<p>This invention relates to an improved valve-gated injection molding system. The hot runner passage through which the melt flows to the cavity is divided into three spiral-shaped channels which converge again immediately before the gate, thereby imparting a curving motion to the melt as it flows outward from the gate in the cavity. This avoids unidirectional molecular orientation of the melt, thereby providing a stronger molded product. In a preferred embodiment of the invention, the melt channels reduce in helical diameter and cross sectional area as they approach the gate, thereby accelerating the swirling motion of the melt.</p> |
