Sprueless injection moulding of thermoplastics - by using the injection nozzle end surface as part of the mould cavity with a restricted diameter inlet

摘要

Sprue-less injection of thermoplastic parts, by solidifying a closure plug permitting tearing away at the surface of the moulding in one or more injection nozzles extending to a moulding, after carrying out the injection process, by corresp. cooling of the nozzle tip. After the tearing away process, the plug is again melted and a new injection cycle carried out. Permits mouldings of the highest quality to be produced from high grade raw material, without waste, the cycle time can be reduced and the costs associated with the sepn of the sprue from the moulding are eliminated.