改性ABS观察孔盖多板模设计

Design of multi-plate mold for observation hole cover of modified ABS

某机床机油观察孔盖塑件需要使用高刚性阻燃工程塑料丙烯腈-丁二烯-苯乙烯塑料针对其注塑成型中模腔浇注和脱模设计都比较困难的生产实际难题,设计了1副一模四腔多板注塑模具用于该塑件的成型。模具中,单腔模腔使用点浇口流道供料给2个内壁潜伏式浇口供料,对模腔进行浇注,既保证了塑件外壁不留浇注痕迹,同时也保证了模腔能获得均衡充填。脱模设计中,重点针对塑件内螺纹的脱模设计了液压马达驱动型内螺纹抽芯机构,保证了塑件内螺纹的无损脱模。为配合塑件的自动脱模,模具分4步开模打开,前3步打开用于流道废料和塑件部分脱模的顺序进行,第4步用于配合螺纹型芯的转动,辅助实现塑件内螺纹及内壁的脱模。塑件最终在顶针将潜伏式流道废料顶出后实现完全脱模。模具结构布置合理,机构选用可靠恰当,有较好的模具结构设计参考意义。

The observation hole cover of a machine tool oil tank is injection molded using the high-rigidity and flame-retardant acrylonitrile-butadiene-styrene engineering plastic for injection molding,and the mold cavity gating and demoulding design were relatively difficult.Aiming at the practical production problems,a set of one-mold four-cavity multi-plate injection mold is designed for the molding of the plastic part.In the mold,the single-cavity mold cavity used the point-gate runner to feed the two inner wall latent gates to pour the mold cavity,which not only ensured that there was no gating trace on the outer wall of the plastic part,but also ensured that the mold cavity can be filled evenly.In the demoulding design,the hydraulic motor-driven internal thread core-pulling mechanism was designed for the demoulding of plastic internal thread,which ensured the nondestructive demoulding of plastic internal thread.In order to cooperate with the automatic demoulding of plastic parts,the mold was opened in four steps,the first three steps were used for the sequence of partial demoulding of runner waste and plastic parts,and the fourth step was used to cooperate with the rotation of the threaded core to assist in the demoulding of the inner thread and inner wall of plastic parts.Finally,the plastic part will be completely demoulded after the ejector pin ejects the waste of the latent runner.The mold structure layout was reasonable,and the mechanism selection was reliable and appropriate,which had good reference significance for die structure design.