• Journal of the Korea Academia-Industrial cooperation Society
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• v.4 no.3
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• pp.172-176
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• 2003

In this paper, we studied the effects of mold temperature on the microstructure of injection molded parts. The weld line decreases in length and width as mold temperature increases. We investigated the dimensional stability of the parts made of two kinds of resin(polypropylene and polystyrene) by varying the mold temperature. As the mold temperature is high, both the shrinkage ratio and the thickness difference for the PS parts decreases. But the observation of PP parts shows a tendency to increase. The easiness of cavity filling and transcription of the mold texture is improved as the mold temperature is high.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2017.05a
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• pp.835-837
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• 2017

In this paper, manufacturing processes of cylindrical composite lattice structures using filament winding method was described. Cylindrical composite lattice structures were manufactured in accordance with four major steps. Silicon mold of lattice shape was installed on mandrel and then continuous fiber was wound on silicon mold. After winding process, in order to ensure the same thickness for all regions, compression process was done for its intersection parts. Finally, the composite lattice structure was demoulded after curing in oven. It was found that the manufactured cylindrical composites lattice structure had 2.4% of dimensional error compared to the design requirements.

• Design & Manufacturing
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• v.8 no.1
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• pp.40-44
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• 2014

As a rotating machine element, plastic gears are more and more widely used in such as industrial machine element, since plastic gear is lighter, higher wear-resistance, and higher vibration absorbing ability than metal gears. When operating plastic parts, tooth breakage and fatigue life shortened due to increasing number of applying load and tooth flank temperature rising, such that accuracy of plastic gears is divided from allowable range to cause vibration and noise. On this study, a internal plastic gears are developed which improved the filling balance molding process by a new injection mold structure. The new mold structure called HR3P(hot runner type 3plate mold). As the result from this studies, we obtained a very accurate roundness internal gears by using design of experiment.

• Design & Manufacturing
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• v.7 no.1
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• pp.40-44
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• 2013

My company develops, manufactures injection mold and produces thin-walled cosmetics and food containers. Without high quality and low production cost, it is hard to compete in the market. To be competitive, a company has to utilize mold with as many cavities as possible to lower manufacturing cost. Eject plate abrasion and deformation cut down mold lifespan, troubles during injection lower productivity and foreign substances in molds cause abrasion. This study focuses on how to improve mold life and productivity, and to slow down mold abrasion.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 1992.04b
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• pp.545-554
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• 1992

본 논문에서는 복합형상의 금형을 가공하기 위하여 필요한 공구와 가공경로를 자동으로 생성해 주는 자동공정계획(CAPP)방법을 제시한다. 금형곡면은 일반적으로 복잡한 형상의 자유곡면들의 조합으로 이루어 지는데 육면체 형상의 소재로부터 원하는 금형곡면을 가공하는데는 수십시간의 기계가공 시간이 소요되며 또한 NC Code를 준비하는데도 같은정도의 시간이 소요된다. 금형곡면의 NC가공에 있어서 또다른 어려움은 공구의 과부하와 공구간섭이 빈번하게 발생할 수 있다는 점이다. 제안하는 자동공정계획방법은 전처리, 공정계획, 공구경로 생성의 3단계로 구성된다. 자동공정계획시스템의 입력정보는 1) 생성될 곡면형상 2) 가공할 소재형상 3) 가공공구 셀(드릴, 볼 엔드밀, 플렛 엔드밀), 절삭성 데이타등이다. 전처리 단계에서는 곡면모델러로부터 생성된 입력 형상을 Z-map이라 부르는 자료구조로 변환한다. 두번째 단계에서는 절삭 가공작업의 순서가 사용되는 공구와 함께 후방순환법에 의하여 결정된다. 그리고 실제 가공될 NC공구경로가 마지막 세번째 단계에서 생성된다.

• 한국금형공학회:학술대회논문집
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• 2008.06a
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• pp.129-133
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• 2008

As a rotating machine element, plastic gears are more and more widely used in such as industrial machine element, since plastic gear is lighter, higher wear-resistance, and higher vibration absorbing ability than metal gears. When operating plastic parts, tooth breakage and fatigue life shortened due to increasing number of applying load and tooth flank temperature rising, such that accuracy of plastic gears is divided from allowable range to cause vibration and noise. On this study, a internal plastic gears are developed which improved the filling balance molding process by a new injection mold structure. The new mold structure called HR3P(hot runner type 3plate mold). As the result from this studies, we obtained a very accurate roundness internal gears by using design of experiment.

• Transactions of the Korean Society of Mechanical Engineers
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• v.16 no.12
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• pp.2252-2260
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• 1992

This paper deals with development of expert process planning system which automatically generates process plan for manufacturing parts of injection mold. The specific domain of study is two-plate injection mold without support plate. Decision making rules for selection of machining processes machine tools, cutting tools and for determination of sequence of machining operations are acquired by interview of skilled process planner. The developed expert process planning system is programmed by using expert system shell CLIPS on the IBM PC/AT. The proposed system works well to real problems.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.8 no.4
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• pp.708-712
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• 2007

Restriking is a shaping method added to the processed products to get higher precision and accuracy in the press die process. This method is frequently used in bending works and drawing works. The purpose of this research is to develop a design for rectangular drawing die punch and die block form which enables drawing formation and restriking in one set.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1991.11a
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• pp.223-227
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• 1991

생산자동화가 필요한 분야 중에서도 대량생산을 유발하고 제품생산의 단납기화, 고품질화를 좌우하는 금형기술은 설계, 가공, 검사공정에 이르기까지 취급해야 할 생산정보의 양이 방대하고 많은 기술축적과 경험을 필요로 한다. 생산정보의 효율적인 처리를 위해 설계와 가공공정에 오래 전부터 컴퓨터가 도입되었으나 단일수량 제품이라는 금형의 특수성 때문에 각 공정에서의 생산정보가 상호 유기적으로 연계되지 않은 곳에서는 전체 생산공정의 총화된 효율향상을 성취하기가 어려웠다.(중략)

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1991.11a
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• pp.194-201
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• 1991

일반적으로 금형공업은 전형적인 중소기업형 공업으로 계획생산보다는 주문 생산방식으로 운영되고 있으며 부가 가치가 높은 산업이다. 또한 업태가 다양하고 산업구조의 선진화에 비례하여 기업체 수가 증가하는 추세이며 고정밀도, 고숙련도를 요하는 고도의 기술 집약적 산업이다. 정밀도의 향상, 인력절감, 자동화와 함께 금형 공장내의 제한된 자원을 효율적으로 이용하고 공장자동화를 촉진하기 위한 각 부문별 자동화 시스템, 컴퓨터 시스템을 정보 Network 로 접속해 공장내 제반관련자료를 유효하게 활용할 수 있는 Total System으로서의 공장운영 시스템의 도입ㆍ필요성이 대두되고 있다.(중략)