• Proceedings of the Korean Society of Precision Engineering Conference
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• 2001.10a
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• pp.46-50
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• 2001

Due to its ability in producing a net-shape product to high precision in a very shot cycle time, injection molding has become one of the most important polymer-processings in the industry today. Recently the CAE applications in the field of injection molding have provided significant contributions to the mold design and process optimization. As a part of such an application the packing process has been studied using C-PARK. The prediction of pressure variations during post-filling stage for amorphous material has been compared with an experimental observation for a simple rectangular geometry of uniform thickness. And the optimal packing processes were calculated using the cavity pressure curve near the gate. As a case study, a warpage simulation was carried out for a DY-HOLDER with the variable number of gates.

• Transactions of the Korean Society of Machine Tool Engineers
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• v.11 no.5
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• pp.81-87
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• 2002

The existing compressor steel seal used in automotive air-conditioner has the problem of oil leakage and deterioration in shielding performance, due to the abrasion and corrosion of the material. A new type of polymer resin seal studied in this research has the characteristics of high anti-abrasiveness and anti-corrosiveness, which can oversome the defects of the steel seal. In addition, the seal needs lower manufacturing cost and is appropriate to mass production, because it is made by the injection molding method requiring no mechanical processing. The profile generation program for seal mold has been developed using the gradient method, and the molding characteristics of the seal have analyzed through the flow analysis and the warpage analysis. The program has been verified by comparing the analysis results with the measured data of the test product. The research might be said to provide the basic method to produce the polymer resin seals with various types and dimensions.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2000.05a
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• pp.1043-1046
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• 2000

By combination of X-ray lithography, electroplating and molding process, various microstructures have been produced. Specially, the alignment grooves for multi-fibers with submicron accuracy have been produced. This paper described a fabrication process of LICA molds and micro molding technique by using LIGA molds. The accuracy of the fabricated LIGA molds was less than 0.4${\mu}{\textrm}{m}$. The injection molded alignment grooves were very precise and had me surface roughness so that they could be successfully applicable to optical systems.

• Transactions of the Korean Society of Machine Tool Engineers
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• v.18 no.2
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• pp.178-186
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• 2009

Most of automotive plastic parts are injection molding products. Inspection of total product is impossible, because number of product to inspect is too many and various. Condition-based Monitoring was proposed to decrease cost and time for inspecting. In this research, a system that predicts quality of part at fabrication point of time, and confirms informations through the internet was developed. Cavity sensors were installed inside of mold, and gathered signals as measuring, and through this process Sensor-based Monitoring system can be observed manufacturing of a part. Monitoring system transmits signals to client through the internet, and finally developed system provides manufacturing informations and predictions of quality as web-based monitoring.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.12 no.1
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• pp.28-34
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• 2013

For the senses of beauty and texture, internal components of small passenger cars are manufactured by texturing plastic with drawplate but those of deluxe passenger cars are manufactured by bonding pre-embossed skin to the surface of drawplate. As the pre-embossed skin is bonded at high temperature and pressure, the pattern of skin is distorted. The corner part is hardened and its dimension tolerance is changed by resulting in the increase with its defective rate. This study provides the method to design and manufacture the door trim track by vacuuming the non-patterned skin to upper-side drawplate which forms the pattern of descending skin. It is pressed to the plastic product with hot-press method and the damage of bossed-pattern is prevented. Valuation in this study has been done by analyzing, designing and experimenting method.

• Electrical & Electronic Materials
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• v.7 no.1
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• pp.64-72
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• 1994

본 고는 현재 전기적 응용을 위한 수지 절연물의 진공/가압 수지-주형처리 분야에서 가장 앞선 기술과 연구개발력을 보유하고 있는 스위스의 Ciba-Geigy사와 최신의 진공성형 시스템을 개발, 생산하고 있는 독일의 Hedrich사 및 진공주형/자동가압 성형장비를 생산하는 스위스의 Vogel사 등을 최근에 방문하여 Epoxy, Polyurethane, Polyester 및 Silicone 수지 등의 수지절연시스템을 가지고 구조적으로 기포가 없으며 전기적, 기계적, 열적특성이 매우 우수하고 매끄러운 표면이 요구되는 수지 mold제품을 생산하는데 적용되고 있는 진공 수지-주형처리기술의 현황과 아울러 경화시간을 크게 단축시켜 생산자동화가 가능한 최신의 자동가압겔화(Automatic pressure gelation)/주입몰드공정(Injection molding process)의 특징 및 기술개발현황에 대해 파악한 내용을 소개하고자 한다.

• Journal of Korean Society for Quality Management
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• v.30 no.2
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• pp.86-98
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• 2002

Defining the relationship between the quality of injection molded parts and the process condition is very complicate because of lots of factor are involved and each factor has a non-linearity. With the development of CAE(Computer Aided Engineering) technology, the estimation of volumetric shrinkage of injection mold parts is possible by computer simulation even though restricted application. In this research, Neural Network applied for finding optimal processing condition. The percent of volumetric shrinkage compared on each case and show neural network can be successfully applied selecting optimum condition not only within factor level but also between factor level.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2002.02a
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• pp.95-102
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• 2002

With recent trends leaning towards product miniaturization, the advent of new material and speedy delivery times, old style conventional trial-and-error methods have been only serving to weaken corporate competitiveness. Reliant on tiny increments of time-consuming experience, this antiquated approach begets a delayed delivery of product development, cost loss and quality depreciation. To solve such problems, the Dedicated Injection Molding CAPA (Computer Aided Plastics Application) performs a preliminary examination on problems rising from every stage of creation - from appropriate material selection and mold design to mass production - through a computer system. Thus, it determines the optimum design variables and process conditions while diagnosing and solving defective molds.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2006.05a
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• pp.533-534
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• 2006

Micro pyramid pattern and its array are designed to enhance the brightness and its uniformity of LGP which is one of key parts in LCD. The designed micro pyramid patterns are fabricated on a Si-wafer first through MEMS process and then a Ni-stamper is electro-plated from the Si pattern master. Adopting the fabricated Ni-stamper, LGPs are injection molded at different mold temperatures and the fidelity of the pattern replication is estimated for each molding conditions and pattern locations. The replicated patterns are found to have some defect such as local short shot or micro weld line which are believed to have negative effect on the performance of the LGP.

• Proceedings of the Korean Powder Metallurgy Institute Conference
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• 2006.09a
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• pp.205-206
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• 2006

A ball-shape alumina arc-tube for low-wattage lamp was developed by the PIM process. An ultra high purity translucentgrade alumina powder was used. In injection molding process, a hot-runner type mold was developed. The translucent-grade alumina powder was extremely sensitive to contamination so that the injection molding condition and atmosphere control in the furnace should be taken care of with extreme caution. Contamination sources were pinpointed with EPMA. The arc-tube was molded in half and two halves were bonded in the middle by a new bonding technique at room temperature developed in this study.