• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2008년도 하계학술발표대회 논문집
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• pp.1167-1171
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• 2008

The flow and thermal performance of the skiving and louver fin type heat sinks for the cooling system of the small LED projector were experimentally evaluated. A small fan tester based on AMCA standards was used to control and measure the air flow rate into the heat sink. Three heat blocks were used to simulate the heat and light sources(red, green and blue) of the small LED projector. We measured the pressure drop, temperatures and input power at the specific air flow rate and discussed those results. As a result, it is found that the louver fin type heat sink has higher pressure drop and lower thermal resistance than the skiving type. From the comparison of the temperature of the heat block between skiving and louver fin type, the louver fin type heat sink was found to be more suitable for cooling the high power heat source than skiving type. The thermal performance of the fan-sink(louver fin type) system was discussed with the picture taken by a thermal video.

• 한국산학기술학회논문지
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• 제13권2호
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• pp.471-477
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• 2012

SCM420재질의 기어를 담금질을 실시한 후 초경호브(Hob)에 PACVD 코팅처리 후 표면경도가 높은 표면(HRC 60)을 절삭하였다. 코팅처리 없이 난삭재(難削材)로 분류되는 경도가 큰것, 경한 물질을 포함한 것, 강도가 높은 것에 공구수명과 생산성을 향상에는 한계성을 가지고 있다. 이를 개선하기 위해 초경호브에 TiCN코팅처리 전후에 대하여 Skiving 절삭으로 코팅처리 한 호브가 가공성이 좋고, 공구마멸이 적어, 공구수명이 2.5배 증가하는 결과를 얻었다. 실험은 CNC 스카이빙 호빙머신을 이용하여 습식절삭으로 절삭속도와 이송량으로 다양한 조건을 적용하여 공구마멸과 표면거칠기 데이터를 얻었다. 실험결과 조건 2에서(V=200m/min F=0.7mm/rev) Cutting speed가 절삭표면에 Feed Mark가 미세하고, 표면거칠기는 Rmax $4.7{\mu}m$(Ra $1.19{\mu}m$)의 데이터를 얻었다.

• 한국생산제조학회지
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• 제21권5호
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• pp.848-854
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• 2012

SCM420 steel cutting gear to improve the durability is quenched. When quenching, increases surface hardness, a change of the physical properties and machinability or fall. This study, using a solid carbide hobs skiving hobbing gear cutting finishing. And cutting tool solid carbide TiAlN coating hove when TiAlN coating on the surface of multi-con polishing hob conducted aero lap nano polishing for each cutting. Experimental results conducted aero lap nano coating on the surface polishing tool machinability was excellent. And aero lap nano polishing tool results were reduced 2.5 times the tool wear compared to TiAlN coated tools. Excellent results were 1.42 times longer tool life.