| 摘要 |
<p>@ This invention relates to an injection molding system in which melt flows in channels in the outer surface of a heated probe seated in the cavity plate on its way to the gate leading to the cavity. The probe has a tip end in alignment with the gate and the probe is reciprocated between open and closed positions to valve gate the flow of melt to the cavity. According to a preferred embodiment, in a multi-cavity system a number of probes are fixed to a manifold which is actuated to valve gate all of the cavities simultaneously. Hydraulic cylinders are provided to drive the manifold to the closed position, and injection melt pressure acting on the tip ends of the probes is utilized to return them to the open position. Valve gating the heated probes provides the advantage of improved temperature control of the melt in the immediate gate area.</p> |
