• Journal of the Korean Society of Manufacturing Process Engineers
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• v.10 no.5
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• pp.85-90
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• 2011

In this paper a design procedure via computer-aided molding simulation is presented to optimize the air-trap locations in a speaker encloser of mobile phone. The molding flow simulation reveals that the race-tracking phenomenon is the dominant feature in the current mold design. In obtaining an optimal filling pattern, the local modifications of the wall thickness such as in a flow leader attachment are considered as the primary control factor, and both the gate position and the filling time become the secondary control factor. In the one-at-a-time approach, the last location to be filled in the mold cavity could be successfully moved to the extremities of the part, allowing a natural ventilation of entrapped air through the mold parting plane.

• The Journal of the Acoustical Society of Korea
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• v.28 no.8
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• pp.796-805
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• 2009

In this paper, a fabrication process for PZT preform of 1-3 type piezo-composite were studied using powder injection molding (PIM). The viscosity and the Pressure-Volume-Temperature (PVT) characteristics of the fabricated PZT feedstock were analyzed. The filling patterns, pressure, temperature distributions, and forming defects of the preform were analyzed with 3D TIMON commercial packages during PIM process. Also the fabrication conditions and the delivery system of the preform were optimized during the entire PIM process. Based on the simulated results, the preform having uniform distributions of the PZT rod was fabricated with the PIM process.

• Proceedings of the KAIS Fall Conference
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• 2003.06a
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• pp.125-128
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• 2003

본 연구는 현재 시판되고 있는 Papst사의 4100 mod디을 대상으로 축방향 송풍기의 사출성형에 대해 MoldFlow 프로그램을 사용하여 제품에 대한 최적의 게이트 위치를 조사하였고 이를 바탕으로 2매 구성금형과 3매 구성금형에 따른 게이트를 설정하여 사출압력, 온도의 변화, 충전 시간 둥을 비교하여 경제성을 고려한 최적의 게이트 위치를 결정하였다. 다수 뽑기 금형에서의 제품 성형에 있어 중요한 변수가 되는 유동주입시스템에서 러너의 크기 변화에 따른 유동선단의 흐름 및 압력과 온도의 변화를 살펴보았고 이러한 시뮬레이션을 통해 시행오차를 최소화 하여 생산비 절감과 품질 향상을 위한 설계를 구현하고자 시도하였다.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.7 no.3
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• pp.271-277
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• 2006

Injection molding process is the manufacturing process that can obtain a high quality products in large quantity to a low cost. Since there are many input factors in every situation that can influence part's quality, the method is difficult to save the exact simulation data. Latest, it deals with the CAE method that supports the experiment, it is applied to the Design of Experiment for the optimum injection molding process. If there are many factors, the interaction among those factors must be considered by applying Design of Experiment which is taken from the technique of minimizing the number of experiment. Without a real test, it is taken the simulation data using $Moldflow^(R)$ software. $Moldflow^(R)$ is used for the analysis of injection molding process, it is analyzed the factors that affect a warpage using the Taguchi method and then the optimal injection molding process is obtained.

• Proceedings of the KAIS Fall Conference
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• 2004.11a
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• pp.83-86
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• 2004

본 연구의 목적은, CAE(Computer Aided Engineering) 기술과 동시설계(Concurrent Design) 방식을 활용하여 0.3mm 정밀박판금형을 설계, 제작하는 것이다. 박판 성형은 기존의 사출성형제품에 비하여 훨씬 얇은 제품을 성형하는 것이기 때문에 수지의 충전 불량 제품의 변형, 과다 내부응력 등 많은 문제점들이 발생한다. 이런 문제점들을 해결하기 위하여 본 연구에서는 컴퓨터 시뮬레이션을 통한 최적성형조건을 찾아내고자 시도하였으며 도출된 조건을 금형설계 및 성형에 적용시킴으로써 최소한의 시행오차를 통한 고부가가치 제품을 성형하였다.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.9 no.6
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• pp.21-28
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• 2010

This study shows an optimization procedure for an automatic determination on the gate position to ensure the fill-uniformity within a part cavity by using the injection molding simulation. For an optimization, the maximum pressure-difference within a part cavity induced at the stage of filling is used to evaluate degree of fill-uniformity. In addition, a direct search scheme based on the reduction of design space is developed and applied in the optimization problem. This corresponding proposed methodology was applied in the optimization on the gate location for a CD-tray molding, as a result, showed the improvement of the fill-uniformity within the cavity.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.9 no.6
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• pp.1494-1499
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• 2008

Plastic materials are utilized to the most important material of automobile interior-parts due to special characteristics that it is light, good strength and do not transmute quality even if pass long time. This study presented a preliminary analysis of fill time, weld line, air trap etc. for the plastic injection molding process of automobile gearbox cover through simulation using Moldflow.

• Journal of the Korea Society for Simulation
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• v.22 no.4
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• pp.83-92
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• 2013

The demand of a camera-lens-module which is installed in mobile phone has been increased explosively as the increase of mobile phone market. Recently, two missions are given to the parts manufacturer of lens module, and they are how to keep the quality of injection moulding process as the increase of resolution, and how to decrease manufacturing cost. In this paper, a simulation study is introduced which is used for developing barrel and shield considering the double-cassette type of mould. At first, the simulation for injection process using Mold Flow$^{TM}$ is applied in the phase of mould design, and mechanical simulation using DPM Assembly$^{TM}$ is applied for collision detection between picking robot and mould. As a result, the productivity increased more than 300%.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.3 no.1
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• pp.1-4
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• 2002

A short shot is a molded part that is incomplete because insufficient material was injected into the mold. Any factors that increase the resistance of polymer melt to flow or prohibit delivery of sufficient material into the cavity can cause a short shot. Inappropriate injection pressure is one of the most common factors which cause a short shot. Conventionally, domain experts in injection molding decide and modify the pressure based on their experience. It is difficult for a non-expert to decide the pressure properly with the considerations such as a part dimension, shape, and other processing variables. In this study, fuzzy algorithm is proposed to standardize the empirical determination of the pressure so that not only the experts but also non-experts can find the appropriate injection pressure easily. To acquire the more accurate results. domain experts should be interviewed and then technical documents which are collected from the experts should be restored in the fuzzy rule base. But in this study, simulations have been done by using C-MOLD to settle the rule base because it takes much time and also it's difficult to meet and interview the experts.

• Proceedings of the KAIS Fall Conference
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• 2001.05a
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• pp.99-102
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• 2001

사출성형에서 제품의 최종 품질에 영향을 미치는 중요한 인자들 중의 하나는 사출압력이다. 전통적으로 현장의 사출전문가는 오래된 현장 경험을 바탕으로 사출압력을 결정한다. 그러나 비전문가에게는 제품의 크기, 형상 그리고 사출공정의 전반적인 과정을 고려하여 적절한 사출압을 찾아내기가 쉽지 않다 본 연구에서는 퍼지 논리(fuzzy logic)를 이용하여 제품도면에 나와 있는 제품두께와 유동길이를 알면 쉽게 초기 사출압을 결정할 수 있도록 전문가의 경험을 규칙베이스화 하였다. 규칙베이스를 구성하기 위해서 현장 전문가들을 인터뷰하고 설문조사를 한 후 기술적인 문서를 작성하여야 하지만 본 연구에서는 C-Mold와 Mold FLOW와 같은 사출해석 프로그램을 이용하여 수 차례의 시뮬레이션을 반복 수행하여 규칙베이스를 구성하였다.