• 한국금형공학회:학술대회논문집
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• 한국금형공학회 2008년도 하계 학술대회
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• pp.111-114
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• 2008

The Injection molding is used more than 70% of total production in plastic products. The injection molding process has 4 processes such as filling, packing, cooling and ejecting. It spends most of times in the cooling process. Therefore, it is important to control the mold temperature in producing plastic products. The cooling system and time affect the product's quality and productivity. Especially, cooling time has about 60% of total injection cycle time. Therefore, we can improve a productivity by shortening cooling time. In this study, the rapid cooling system was developed and performed a efficiency test. This system could refrigerate coolant to $1^{\circ}C$ and had to need 10 minutes for normal operating. However, if response time of temperature controller and sensor will be increased, the performance of this system will increase.

• 한국금형공학회:학술대회논문집
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• 한국금형공학회 2008년도 하계 학술대회
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• pp.175-181
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• 2008

The technologies of mold design, manufacturing, injection molding process and computer aided engineering(CAE) are developed rapidly with the growth of plastic product market. Injection molding process optimum design can not be easily determined. This study was determined factors and levels which carried out to analyze an influence of narrow pitch BGA socket warpage and performed investigating the main effect and interaction effect between factors using design of experiment. The result of this paper is injection time and packing pressure are affect on narrow pitch BGA socket warpage at injection molding.

• 한국전기전자재료학회논문지
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• 제16권9호
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• pp.771-774
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• 2003

In this paper, the programming characteristics of the multi-bit devices based on SONOS structure are investigated. Our devices have been fabricated by 0.35 $\mu\textrm{m}$ complementary metal-oxide-semiconductor (CMOS) process with LOCOS isolation. In order to achieve the multi-bit operation per cell, charges must be locally frapped in the nitride layer above the channel near the source-drain junction. Programming method is selected by Channel Hot Electron (CUE) injection which is available for localized trap in nitride film. To demonstrate CHE injection, substrate current (Isub) and one-shot programming curve are investigated. The multi-bit operation which stores two-bit per cell is investigated. Also, Hot Hole(HH) injection for fast erasing is used. The fabricated SONOS devices have ultra-thinner gate dielectrics and then have lower programming voltage, simpler process and better scalability compared to any other multi-bit storage Flash memory. Our programming characteristics are shown to be the most promising for the multi-bit flash memory.

• 자원리싸이클링
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• 제1권1호
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• pp.37-43
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• 1992

The submerged injection smelting process was performed to recover Zn and Pb from steel dust throuth vaporization and to investigate the effect of temperature, slag composition, injection time, gas flow rate, etc. on the recoveries of valuable metals. The results show that vaporation rates of zinc and lead increased at higher temperture and higher moral ratio of ferrous to ferric oxides. In the initial stage of submerged injection of nitrogen gas, the molten slags of the dust have high value of molar ratio of $Fe^{2+}$/$Fe^{3+}$ and hence zinc and lead can be effectively recovered.

• 한국기계가공학회지
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• 제18권3호
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• pp.82-87
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• 2019

Recently, plastic materials have become more diversified, and the development of materials with excellent mechanical properties and plasticity has enabled wider application, miniaturization, and refinement of injection molded products. As a result, the utilization of these products in household goods, electronics, automotive parts, and aircraft parts is increasing in almost all industries. Injection molded parts are often used externally on finished commercial products. This means that the injection mold industry is very important to the value of these products. For this reason, the industry is performing research on the precision and efficiency of the injection molding process. In this study, we investigated the applicability of the core in core cooling method to the problem of product deformation due to temperature variation in existing injection mold designs. We also characterized the cooling performance of an injection mold when using this cooling method.

• 정보처리학회논문지:소프트웨어 및 데이터공학
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• 제5권12호
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• pp.635-640
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• 2016

생산 시스템의 신뢰도와 공정에서의 품질관리는 수익과 직결되는 중요한 요소이다. 이런 이유로 M2M 디바이스 레벨에서 데이터를 획득하는 방법 그리고 그것을 응용하여 신뢰도 및 품질 등과 연결하는 연구에서 최근 많은 성과를 보이고 있다. 본 논문은 이러한 연구 결과의 연장으로 획득한 데이터의 처리방법과 결과에 관한 것이다. 일반적으로, 센서 데이터와 같은 미세한 차이를 가지는 신호를 이용하여 제품의 품질을 식별하는 것은 기존의 통계적인 방법에서는 어렵다. 그러나 최근 기계 공정에서 정보를 실시간적이고 즉시적으로 처리를 해야 하는 요구가 증대되고 있다. 특히 사출성형 공정의 경우 프로세스가 짧은 Cycle 갖고 있어 프로세스의 진행과 동시에 제품의 양-불량을 판별할 수 있는 방법이 필요하다. 본 논문은 Kalman Filter를 적용하여 사출공정의 센서 데이터를 실시간적으로 처리하여 제품의 상태를 판단할 수 있는 방안을 제시한다.

• 동력기계공학회지
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• 제9권4호
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• pp.83-89
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• 2005

Molding shrinkage is one of the problems to be solved in conventional injection molding. Despite many trying-out has been to solve it, intrinsic cause of shrinkage such as orientation and thermal exchange between melt and mold has not been solved yet. For reducing shrinkage and residual stress on molding, injection compression molding process was invented. In this study, experiments about effects of injection compression molding's parameters on shrinkage of PMMA molding were conducted and compared with conventional injection molding's shrinkage. Before the injection compression molding experiment, molding shrinkage rate was predicted by analyzing pvT diagram and was compared with the results of experiment. The shrinkage rate of injection compression molding was lower than convention injection molding's one which was different from the predicted shrinkage. The reason was observed that the experimental mold was not a proper type for injection compression, flowing backward of melt into nozzle and unreasonable mechanism of injection molding machine.

• Design & Manufacturing
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• 제9권2호
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• pp.10-15
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• 2015

The water has been the suitable for the cooling medium until now. But the water as cooling medium seem to have the limit for high speed injection. The steam plastic molding injection use the steam as the medium when raise the mold temperature. The weld line has been the major quality problems in a plastic injection parts to be difficult to be solved. These problems in injection-molded plastic parts are difficult to find the reason because these issues are usually in tradeoff realtions with each other. The purpose of this paper is to obtain the optimum injection moulding condition for improving the quality of plastic injection parts and to inquire the productivity improvement with the measured cycle time by steam plastic moluding injection. Based on these numerical results, the guidelines of mould design and injection processing condition were established. As a result, the improvement of quality and the reduction of cycle time was achieved.

• 한국기계가공학회지
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• 제19권9호
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• pp.53-58
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• 2020

This study analyzed the surface roughness of the fine particle spraying process in the plane and the surface roughness by the factors in the fine particle spraying process on the helical surface is analyzed. Finally, the surface fine particle spraying process and the helical curved surface fine particle Analyze the difference in injection conditions of the injection process. Key process variables are particle type, nozzle diameter, and pressure. The remaining conditions are fixed values of. A total of 32 experiments were conducted, each with different process variables. Rectangular and cylindrical specimens were fabricated and a corresponding jig was prepared for use in the experiment. Analyses conducted by using ANOVA enabled comparisons of the effects of each process variable on the experiment.

• 한국기계가공학회지
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• 제17권6호
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• pp.98-104
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• 2018

Deflected 4-way panels of ceiling air conditioners produced by injection molding process have caused dew condensation at the edge of products. In order to prevent this drawback with reducing weight and deformation, this study proposed renovated process adopting microcellular foaming. According to results from 2-sample t-test and analysis of variance(ANOVA), the critical factors affecting weight were melt temperature and injection speed. In addition, the vital effects on deformation were structure at the edge, mold temperature and cooling time. Optimal conditions of these parameters were derived by regressive analysis with CAE and response surface method(RSM), and then applied to an actual design and process stage to analyze performance. As a results, it clearly showed that new process improved process capability as well as reduced both weight and deformation by 18.8% and 71.9% respectively compared to the conventional method.