One-time injection molding method for totally-cladded plastic product

Abstract

The invention discloses a one-time injection molding method for a totally-cladded plastic product. The one-time injection molding method for the totally-cladded plastic product comprises the following steps that (1) before injection, a mold core (1) to be cladded is fixed in the middle of a mold cavity (11) to be formed after mold assembly by means of a plurality of supporting rods (12) which are symmetrically arranged; (2) mold assembly is conducted, molten resin (14) is injected from a nozzle (13), and the amount of the injected resin meets the condition that the mold cavity is gradually filled with the resin but not completely filled with the resin; and (3) in the later injection state during which the injection amount reaches a certain value or the pressure maintaining stage, the supporting rods (12) are made to retreat from a mold to positions (121) flush with the edge of the mold cavity by means of a core-feeding and core-retreating device, residual resin (14) continues to be injected into the nozzle (13), and the core-feeding and core-retreating device is controlled through a second hydraulic system which is additionally arranged in an injection molding machine, namely the injection molding machine comprises a first hydraulic system used for controlling injection molding and the second hydraulic system used for controlling the core-feeding and core-retreating device; and (4) injection is ended, the mold is opened after being cooled, and the product (2) is taken out.

Description

technical field [0001] The invention relates to the injection molding technology of plastic products, in particular to a one-time injection molding method of fully covered plastic products. Background technique [0002] Due to their good mechanical strength and corrosion resistance, plastic products are widely used in various fields such as electronic appliances, semiconductors, solar energy, LEDs, chemical anticorrosion, machinery manufacturing, and building materials. However, because the rigidity of plastic products is insufficient compared with metal, or the thickness of the product to be used is too large to be injection molded (the thickness is too large to cause collapse), etc., it is necessary to use a fully covered plastic product with a core. Meet the requirements of the product. For example, high-strength, corrosion-resistant plastic products formed by metal cores coated with anti-corrosion resin; thick-walled products with hollow metal rods (or rods or plates, e...

AI Technical Summary

Problems solved by technology

It can be seen that the injection molding machine of the prior art does not have a hydraulic system that can be used to control the advance and retreat of the support rod during the injection process, so it is impossible to achieve a one-time injection to obtain a fully coated product

[0011] CN103395162A discloses a method for manufacturing a fully-coated corrosion-resistant magnetic pump shaft. A hollow cylindrical support rod is used to position the mandrel in a hollow metal core, and injection molding is performed in three stages to obtain products. However, the injection molding process of this method It is relatively complicated, and the inner rod of the mandrel needs to be pulled out after the injection is completed, which increases the operation steps and is not conducive to the improvement of production efficiency

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