CN103552213A

CN103552213A - Method for solving jet lines at side gate on thick wall during injection molding

Info

Publication number: CN103552213A
Application number: CN201310548603.0A
Authority: CN
Inventors: 吴春
Original assignee: SHANGHAI YAHONG MOULDING CO Ltd
Current assignee: SHANGHAI YAHONG MOULDING CO Ltd
Priority date: 2013-11-07
Filing date: 2013-11-07
Publication date: 2014-02-05

Abstract

The invention provides a method for solving jet lines at a side gate on a thick wall during injection molding. The method is characterized in that an injection direction aims at a side wall surface of a product, so that an included angle is formed between the injection direction and the side wall surface of the product and is 25-60 degrees. According to the method provided in the invention, the defects of the prior art are overcome, an injection direction of the gate is changed according to the design, the jet line defects are completely overcome, the quality qualified ratio of the molded appearance of the product is improved, no cost is generated, and the method is not limited by molding materials and is suitable for various injection molding materials.

Description

A kind of method that solves injection mo(u)lding heavy wall side gate place spray pattern

Technical field

The present invention relates to a kind of method that solves injection mo(u)lding heavy wall side gate place spray pattern, belong to injection molding technology field.

Background technology

At present; for injection mo(u)lding; gate form has side gate, sub marine gate, point type cast gate and style big water gap etc. conventionally; and in actual injection molding process; near cast gate, usually there will be the defect problems such as cast gate swash, cast gate color spot; in view of the requirement of client to outward appearance, Design of Dies usually can be selected submarine to enter cast gate or place into cast gate in non-appearance.But, some product is in view of moulding material characteristic and product structure requirement, only have the side of selection to enter gate form, particularly at the thicker wall thickness place of product, as shown in Figure 1, wall thickness T is greater than 3mm, when (because general plastic product wall thickness is at 1～2.5mm) side is entered cast gate, unavoidably can run into cast gate spray pattern, this will directly cause product surface outward appearance to have spray pattern defect.

Summary of the invention

The technical problem to be solved in the present invention is to provide a kind of method that solves injection mo(u)lding heavy wall side gate place spray pattern, to improve formed product presentation quality qualification rate.

In order to solve the problems of the technologies described above, technical scheme of the present invention is to provide a kind of method that solves injection mo(u)lding heavy wall side gate place spray pattern, it is characterized in that: injection pointing needle, to product side wall surface, makes injection direction and product side wall surface form angle.

Preferably, described angle is 25 °～60 °.

The method of solution injection mo(u)lding heavy wall side gate provided by the invention place spray pattern is mainly the improvement for the spray pattern open defect of injection mo(u)lding heavy wall side gate region generation, the method of improving is to enter cast gate design by optimizing mould, change injection direction, while making moulding, plastic cement is avoided directive die cavity space freely, but direct directive cavity side wall enters cast gate spray pattern defect thereby thoroughly solve thick wall area side.

Method provided by the invention has overcome the deficiencies in the prior art, by change in design, enters cast gate injection direction, has thoroughly solved spray pattern defect, improved formed product presentation quality qualification rate, do not produce any cost, and be not subject to the restriction of moulding material, be applicable to all kinds of injection mo(u)lding materials.

Accompanying drawing explanation

Fig. 1 enters cast gate, the cast gate spray pattern schematic diagram of generation for be not less than the product side of 3mm for wall thickness;

Fig. 2 is that Design of Dies changes into cast gate injection angle schematic diagram;

Fig. 3 is transparent circular glass product schematic diagram in embodiment 1;

Fig. 4 is glue position directive schematic diagram in embodiment 1;

Fig. 5 is transparent square glass product schematic diagram in embodiment 2;

Fig. 6 is front mould side wall surface glue position directive schematic diagram in embodiment 2;

Fig. 7 is rear mold side wall surface glue position directive schematic diagram in embodiment 2.

The specific embodiment

For the present invention is become apparent, hereby with two preferred embodiments, and coordinate accompanying drawing to be described in detail below.

The principle that heavy wall side gate place produces cast gate spray pattern is because plastic material, when entering glue filling from heavy wall side gate, always has the free space region of directive heavy wall die cavity, has formed the spray pattern of similar snake shape.The design of entering cast gate injection angle by changing mould, make plastic cement filling directive cavity lateral as far as possible, and the die cavity of non-NULL can thoroughly solve the spray pattern defect at heavy wall side gate place.

Design of Dies changes into cast gate injection angle, as shown in Figure 2, avoids the free space region of glue position filling directive die cavity, makes the cavity lateral on directive top, glue position and side both direction, thereby solves spray pattern defect.

Embodiment 1

In conjunction with Fig. 3, product is transparent circular glass, and material is PMMA (polymethyl methacrylate), and mould one goes out two caves, and product size is diameter

, side gate region wall thickness H is 5.5mm.In conjunction with Fig. 4, because product is circular, therefore only have bottom surface A to be appropriate to elect as the side wall surface of side gate directive, P is die parting line.Design glue position directive angle, cast gate front mould part glue position directive angle [alpha] 1 is 35 °, and cast gate rear mold part glue position directive angle [alpha] 2 is 30 °, and actual moulding checking has thoroughly solved cast gate place spray pattern defect.

Embodiment 2

In conjunction with Fig. 5, product is transparent square glass, material PMMA, and mould one goes out a cave, and P is die parting line.In conjunction with Fig. 6, it is 5mm that product side is entered the wall thickness L of cast gate place, because the thickest region of product wall thickness is in the square corner of product, be that desirable setting side enters cast gate place, therefore select the sidewall on front mould side wall surface B and rear mold side wall surface C both direction, its front mould side wall surface glue position directive angle [alpha] 3 is 25 °, in conjunction with Fig. 7, rear mold side wall surface glue position directive angle [alpha] 4 is 60 °, and actual moulding checking has thoroughly solved cast gate place spray pattern defect, constant product quality.

The method of solution injection mo(u)lding heavy wall side gate provided by the invention place spray pattern changes injection direction by design, moulding material is had to universal applicability, implementation cost without, implementation result is very thorough, certainly, this type of cast gate design, not only for transparent PMMA material, also comprise other injection mo(u)lding plastic cement, as ABS (copolymer of acrylonitrile, styrene and butadiene), PP (polypropylene), PBT (poly-to stupid dioctyl phthalate fourth diester) etc.

Claims

1. a method that solves injection mo(u)lding heavy wall side gate place spray pattern, is characterized in that: injection pointing needle, to product side wall surface, makes injection direction and product side wall surface form angle (α).

2. a kind of method that solves injection mo(u)lding heavy wall side gate place spray pattern as claimed in claim 1, is characterized in that: described angle (α) is 25 °～60 °.