• Design & Manufacturing
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• v.14 no.2
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• pp.42-48
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• 2020

This study is on the injection molding analysis for the LED outdoor lighting top cover of one heat sink body type structure. Thermoplastic and thermosetting resins were applied to compare the thermal properties during the injection molding process. The thermoplastic resin is used in this study due to special characteristics that it is light, good strength and dose long not transmute quality even if pass long time. The thermosetting resin is applied to this study due to good in strength, lightweight and excellent etc, thermal conductivity. This study presented a preliminary analysis of fill time, weld line, air trap etc. for the injection molding process of LED lamp cover and body through simulation using Moldflow. As a result of the study, it was selected HTM-102 material because the thermosetting resin has excellent strength and heat conductivity.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2010.11a
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• pp.593-594
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• 2010

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.20 no.1
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• pp.81-85
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• 2011

Recently, the electronic parts are to be thinner plate, smaller size, light weight material and CPU, HDD and DRAM in all the parts have been produced on the basis of the high speed and greater capacity. Also, conventional goods have replaced a LED (Light-Emitting Diode) in lighting products so; such industry devices need to have cooling. To maximize all the performance on the heat-radiated products, the area of heat-radiated parts is required to be cooled for keeping the life time extension and performance of product up. Existing cooling systems are using radiant heat plate of aluminum, brass by extrusion molding, heat pipe or hydro-cooling system for cooling. There is a limitation for bringing the light weight of product, cost reduction, molding of the cooling system. So it is proposed that an alternative way was made for bringing to the cooling system. EP (Engineering Plastic) of low-cost ABS (Acrylonitrile butadiene styrene Resin) and PC (Polycarbonate) was coated with brass and the coating made the radiated heat go up. The performance of radiant heat plate is the similar to the existing part. We have studied experimentally on the radiated heat plate for the light-weight, molding improvement and low-cost. From now on, we are going to develop the way to replace the exiting plate with exterior surface of product as a cooling system.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2009.11a
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• pp.165-165
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• 2009

긴 수명, 높은 효율, 색 재현성 및 친화경등의 많은 장점을 가진 발광다이오드는 높은 접합온도로 인하여 광 효율이 저하되고 이는 신뢰성 저하 및 방열부 장착으로 인한 비용 상승 등의 문제로 발전에 악영향을 받고 있다. 본 논문에서는 방열부인 HeatSink의 구조적 변화가 방열성능에 어떠한 영향을 끼치는지 알아보기 위해 열화상 적외선 카메라와 적분구를 이용하여 서로 다른 HeatSink를 가지고 각각의 열적 광학적 특성을 파악하였다. HeatSink의 Fin 길이를 길게 하여 방열면적을 상승시키는 것보다 Fin 두께를 작게 함으로써 Fin 개수를 늘리는 것이 방열성능을 크게 개선시킬 수 있었고 이는 광 출력으로 이어졌다.

• Journal of the Korean institute of surface engineering
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• v.51 no.6
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• pp.415-420
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• 2018

The possibility of an improvement in heat dissipation performance of aluminum alloy heat sink for shipboard LED luminaries through plasma electrolytic oxidation (PEO) was investigated. Four different PEO coatings were produced on aluminum alloy 5052 in silicate based alkaline solution by varying current density ($50{\sim}200mA/cm^2$). On voltage-time response curves, three stages were clearly distinguished at all current densities, namely an initial linear increase, slowdown of increase rate, and steady state(constant voltage). It was found that the increase in current density caused the breakdown voltage to increase. Two different surface morphologies - coralline porous structure and pancake structure - were confirmed by SEM examination. The coralline porous structure was predominant in the coatings produced at lower current densities (50 and $100mA/cm^2$) while under high current densities(150 and $200mA/cm^2$) the pancake structure became dominant. The coating thickness was measured and found to be in a range between about $13{\mu}m$ and $44{\mu}m$, showing increasing thickness with increasing current density. As a result, $100mA/cm^2$ was proposed as an effective process parameter to improve the heat dissipation performance of aluminum alloy heat sink, which could lower the LED operating temperature by about 30%.

• Design & Manufacturing
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• v.10 no.3
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• pp.14-19
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• 2016

Thermally or electrically conductive filler reinforced polymer composites are extensively being developed as the demand for light weight material increases rapidly in industiral applications need good conductivity such as heat sink of the electronics or light. Carbon or ceramic materials like graphite, carbon nanotube or boron nitride are typical conductive fillers with good thermal or electical conductivity. Using these conductive fillers, the polymer composites in the market show wide range of thermal conductivity from approximately 1 W/mK to 20 W/mK, which is quite enhanced considering the thermal conductivity lower than 0.5 W/mK for most polymeric materials. The practical use of these composites, however, is yet limited to specific applications because most composites are still not conductive enough or too difficult to process, too brittle, too expensive for higher conductivity. For practical use of conductive composite, the thermal conductivity required depending on the heat releasing mode are studied first for simplified unit cooling geometry to propose thermal conductivities of the composites for reasonable cooling performance comparing with the metal heat sink as a reference. Also, as a practical design for heat sink based on polymer composite, composite and metal sheet hybrid structures are investigated for LED lamp heat sink and audio amplication module housing to find that this hybrid structure can be a good solution considering all of the cooling performance, manufacturing, mechanical performance, cost and weight.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2012.05a
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• pp.691-692
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• 2012

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2012.05a
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• pp.799-800
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• 2012

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2011.06a
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• pp.1017-1018
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• 2011

• Journal of Satellite, Information and Communications
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• v.10 no.1
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• pp.77-82
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• 2015

In this paper, we perform a study on LED Fluorescent Lamp applying Circuit Driven Method to Tubular LED Lamp Converter. The energy efficiency of LED fluorescent lamp converter requires exceptional protection circuit design, circuit design and structure, because it can not take advantage of Heat-sink structure of the heightened degree Reflector for Fluorescent Lamp. In this paper, we performed a study on LED fluorescent lamp applying circuit driven method to tubular LED lamp converter, Also, we designs LED lamp and converter which can supply DC power common commercial power source.