摘要 |
A novel valve gated injection molding system and valve gate reduces the formation of gate vestiges on parts molded therewith and enhances cooling of the tip of the valve stem during the cooling portion of an injection molding cycle. Channels are provided and extend from an area adjacent the contact area of the sealing portions of the stem tip and gate to the melt channel of the injection nozzle. These channels allow material, which would otherwise form a thin film layer in the contact area of the sealing portions of the stem tip and gate, to be expressed through the channels and back to the injection nozzle. As the formation of thin films is inhibited, an increased contact area, in addition to the contact area of the tip and gate sealing portions, can be provided to improve the transfer of heat energy from the tip to the gate when the gate is cooled.
|