Shut off nozzle system and methods for making and using the same

摘要

In one embodiment, a tool, comprising: a tool stationary portion comprising a nozzle and a film gate; and a tool movable portion comprising a shut off pin opposite the nozzle and the film gate; wherein the shut off pin prevents polymer melt in the nozzle from leaking into a cavity of the tool after injection of polymer into the tool.

主权项

1. A method of making a shaped part, comprising:
closing a tool comprising a first portion comprising a nozzle and a second portion comprising a shut off pin opposite the nozzle, and a film gate and a mold cavity formed between the first portion and the second portion; injecting polymer melt into the mold cavity of the tool, wherein the polymer melt flows through the nozzle and through the film gate; blocking the nozzle by direct contact with the shut off pin; completing a compression stroke wherein the mold cavity is compressed, a thickness of the film gate is decreased, and the shut off pin moves; releasing the shut off pin; pushing the shut off pin in the opposite direction of the nozzle; opening the tool; ejecting the shaped part; and pulling leftover material from the nozzle with the shut off pin.