Reciprocating compressing and injection molding method of plastic jetting-molding machine

Abstract

Provided is a reciprocating compression molding method of injection molding machines, the steps of which includes: (1) stopping the mold-closing to perform injection when the mold-closing reaches the initial mold-shutting position; (2) movable die plates backing to the position of suction opening mold to stop when an injection screw reaches the screw position of starting compression; (3) performing the mold-locking when the maintaining time of the suction opening mold is over and continuing injecting without stopping during the time when coming to the end of mold-locking position. The invention has the advantages that thin-wall foaming can be effectively realized and the vivid surface treatment is achieved, simultaneously the radial shunt trace of the products with large flow length ratio is avoided, the problem that the product property is twisted resulting from the unable filling and the residual stress of finished products is resolved, not only are the dimensional accuracy and the surface accuracy increased, but also the volume can be continuously changed according to the need of molding space of mold cavity, and as the compression molding method belongs to the category of low-pressure injection, the method is particularly adaptable to the thin-wall foaming technique, thereby largely extending the usage of the injection molding machines.

Description

technical field [0001] The invention relates to a molding method of an injection molding machine. Background technique [0002] Existing ordinary hydraulic injection molding machines only have the injection method of locking the mold and then injecting. This molding method is difficult to control precisely. In the actual work of the injection molding machine, it is necessary to produce various products, especially those with high quality requirements. Products, therefore, this single injection method is difficult to adapt to actual needs, and it is also difficult to meet the needs of high-quality products. [0003] The compression methods that have appeared in the all-electric injection molding machine are: non-linked mold clamping compression injection, linked mold clamping compression injection, cooling room ejection, etc., but these methods are still not effective for foaming during the molding process. The countermeasures cannot meet the production needs well, and there...

AI Technical Summary

Problems solved by technology

[0002] Existing ordinary hydraulic injection molding machines only have the injection method of locking the mold and then injecting. This molding method is difficult to control precisely. In the actual work of the injection molding machine, it is necessary to produce various products, especially those with high quality requirements. Products, therefore, this single injection method is difficult to adapt to actual needs, and it is also difficult to meet the needs of high-quality products

[0003] The compression methods that have appeared in the all-electric injection molding machine are: non-linked mold clamping compression injection, linked mold clamping compression injection, cooling room ejection, etc., but these methods are still not effective for foaming during the molding process. The countermeasures cannot meet the production needs very well, and there will be radial shunt marks in the product with a large flow-to-length ratio, failure to fill, and product property distortion caused by residual stress of the finished product.

[0004] In order to improve the quality of foamed products, the existing technology must use specially manufactured special equipment to realize the low-pressure injection function