• 한국산학기술학회논문지
• /
• 제4권3호
• /
• pp.172-176
• /
• 2003

본 논문은 금형의 온도 변화가 사출성형품의 미시구조에 미치는 영향에 관해 연구했다. 웰드라인의 폭과 길이는 금형온도가 증가함에 따라 모두 감소되었다 그리고 금형의 온도에 따른 결정성수지인 PP(Polypropylene)와 비결정성수지인 PS(Polystyrene)의 치수안정성에 관해 연구했다. PS성형품은 금형온도가 높을수록 수축률이 줄어들고, 두께 편차가 적어졌고, PP성형품의 경우에는 결정의 생성으로 인해 상반된 경향이 나타났다. 캐비티의 충전성과 전사성은 금형온도가 높을수록 향상되었다.

• 정보저장시스템학회:학술대회논문집
• /
• 정보저장시스템학회 2005년도 추계학술대회 논문집
• /
• pp.26-30
• /
• 2005

Stamper surface temperature is very critical in replicating the high density optical disc substrates using injection molding as the pit or land/groove patterns on the optical disc substrate have decreased due to the rapid increase of areal density. During the filling stage, the polymer melt in the vicinity of the stamper surfaces rapidly solidifies and the solidified layer generated during polymer filling greatly deteriorates transcribability and fluidity of polymer melt. To improve transcribability and fluidity of polymer melt, stamper surface temperature should be controlled such that the growth of the solidified layer is delayed during the filling stage. In this study, the effect of heating on replication process was simulated numerically. Then, an injection mold equipped with instant active heating system was designed and constructed to raise the stamper surface temperature over the glass transition temperature during filling stage of the injection molding. Also, the closed loop controller using the Kalman filter and the linear quadratic Gaussian regulator was designed. As a result, the stamper surface temperature was controlled according to the desired reference stamper surface temperature.

• 정보저장시스템학회논문집
• /
• 제2권2호
• /
• pp.100-104
• /
• 2006

Stamper surface temperature is very critical in replicating the high density optical disc substrates using injection molding as the pit or land/groove patterns on the optical disc substrate have decreased due to the rapid increase of areal density. During the filling stage, the polymer melt in the vicinity of the stamper surfaces rapidly solidifies and the solidified layer generated during polymer filling greatly deteriorates transcribability and fluidity of polymer melt. To improve transcribability and fluidity of polymer melt, stamper surface temperature should be controlled such that the growth of the solidified layer is delayed during the filling stage. In this study, the effect of heating on replication process was simulated numerically. Then, an injection mold equipped with instant active heating system was designed and constructed to raise the stamper surface temperature over the glass transition temperature during filling stage of the injection molding. Also, the closed loop controller using the Kalman filter and the linear quadratic Gaussian regulator was designed. As a result. the stamper surface temperature was controlled according to the desired reference stamper surface temperature.

• 한국정밀공학회:학술대회논문집
• /
• 한국정밀공학회 2006년도 춘계학술대회 논문집
• /
• pp.407-408
• /
• 2006

Almost all injection molds have multi-cavity, which are designed with geometrically balanced runner system in order to made filling balance between cavity to cavity during injection molding. However, filling imbalance has been existed in the geometrically balanced runner system. In this study, we made an experiment and surveyed that are filling balanced variation according to molding condition with thermoplastic vulcanizate (TPV). Also, we conducted experiments in order to know the influence of filling balance for runner core pin (RC pin).

• 대한기계학회논문집A
• /
• 제23권7호
• /
• pp.1075-1084
• /
• 1999

The family of unidirectional continuous fiber reinforced polymeric composites are currently used in automotive bumper beams and load floors. The material properties and mechanical characteristics of the compression molded parts are determined by the curing behavior, fiber orientation and formation of knit lines, which are in turn determined by the mold filling parameters. In this paper, a new model is presented which can be used to predict the 3-dimensional flow under consideration of the slip of mold-composites and anisotropic viscosity of composites during compression molding of unidirectional fiber reinforced thermoplastics for isothermal state. The composites is treated as an incompressible Newtonian fluid. The effects of longitudinal/transverse viscosity ratio A and slip parameter $\alpha$ on the buldging phenomenon and mold filling patterns are also discussed.

• 동력기계공학회지
• /
• 제18권3호
• /
• pp.51-58
• /
• 2014

Injection molding simulation provided optimized design results by analyzing quality problems while the product is in assembly or in the process of manufacturing with make automobile plastics. Frequent change of design, change of injection molding, repetition of test injection which was held in the old way can now be stopped. And quality upgrade is expected instead. This report deals with the effect which the position of injection molding automobile console gate and number has on product quality including pressure at end of fill, bulk temperature at end of fill, shear stress of end of fill, residual stress at post filling end, product weld lines and warpage results. Simpoe-Mold simulates the complete manufacturing process of plastic injected parts, from filling to warpage. Simpoe-Mold users, whether they are product designers, mold makers or part manufacturers, can identify early into the design stage potential manufacturing problems, study alternative solutions and directly assess the impact of such part modification, whatever the complexity and geometry of such parts, shell part as plain solid parts.

• 산업경영시스템학회지
• /
• 제38권1호
• /
• pp.44-51
• /
• 2015

When manufacturing die casting mold, generally, the casting layout design should be considered based on the relations of injection system, casting condition, gate system, and cooling system. According to the various relations of the conditions, the location of product defects was differentiated. High-qualified products can be manufactured as those defects are controlled by the proper modifications of die casting mold with keeping the same conditions. In this research, Computer Aided Engineering (CAE) simulation was performed with the several layout designs in order to optimize the casting layout design of an automotive part (Housing). In order to apply them into the production die-casting mold, the simulation results were analyzed and compared carefully. With the filling process, internal porosities caused by air entrapments were predicted and also compared with the modification of the gate system and overflow. With the solidification analysis, internal porosities occurring during the solidification process were predicted and also compared with the modified gate system. The simulation results were also applied into the production die-casting mold in order to compare the results and verify them with the real casting samples.

• 실천공학교육논문지
• /
• 제9권2호
• /
• pp.119-124
• /
• 2017

사출성형 시 유압실린더의 힘으로 스크류가 앞으로 전진하는 동안, 금형의 러너시스템은 성형품 형상의 캐비티 내를 충진시키는 유로로 용융된 수지의 충진, 패킹과정에 관계되며, 이는 스프루(sprue), 러너(runner), 게이트(gate)에 의해서 성형품의 외관, 수지의 물성, 치수 정밀도 및 성형 사이클 등에 큰 영향을 준다. 러너, 게이트 설계가 잘못된 피드시스템은 다양한 성형불량을 일으키므로 이를 방지할 수 있는 최적의 러너밸런스를 유지하는 것이 중요하다. 사출금형을 제작하는 업체에서 응용할 수 있는 실무적인 금형기술 지식을 향상시키기 위해서 기술적인 애로분야에 대한 기술지도를 바탕으로 금형기술 과정의 훈련모델을 제시한다.

• Design & Manufacturing
• /
• 제8권1호
• /
• pp.40-44
• /
• 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.

• 한국정밀공학회:학술대회논문집
• /
• 한국정밀공학회 1993년도 춘계학술대회 논문집
• /
• pp.323-327
• /
• 1993

Mold-making industry demands currently to reduce the tooling costs and time in mold making, and to improve the productivity and quality in injection molding process. These problems can be easily removed by laminated injection mold which is made with metal sheets prepared by laser cutting and bonded by brazing. Comparing withthe conventional mold making technology which mainly depends on the machining, this new technologyenables an arbitary design of cooling circuit without anyrestrictions of geometry. So it brings about high production rates of the injection molding processes. This paper estimate the conventional and laminated injection mold making process with a simple molding, and also the cooling efficiencyof thoes two kinds of mold with the filling and cooling analysis. The results show that the laminated injectionmold has much shorter tooling time, uniform mold temperature, and shorter cooling time in injection molding process.