• 한국기계가공학회지
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• 제7권3호
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• pp.55-60
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• 2008

Until a recent date, the surface finish generated in turning by the conventional cutting tool is directly related to the feed rate and the size of the tool nose radius. With this tool a large feed rate will give poorer surface finish and a large nose radius will generate a better surface finish. Recently a new concept in the tool design is introduced to achieve a better surface finish at a higher feed rate. This is the wiper tool, which has the portion of nose with infinite radius. This can remove the ridges left when the conventional tool is used. In this study two series of cutting tests with the wiper tool and the conventional tool are carried out under the various cutting conditions of cutting depth, feed rate and cutting speed. The effects of the wiper design and the cutting conditions on the surface roughness resulted are carefully examined and compared.

• The Korean Journal of Ceramics
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• 제2권4호
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• pp.203-211
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• 1996

CVD diamond tools are becoming more widely used in industry as an economic alternative to polycrystalline diamond (PCD) for machining non-ferrous and non-metallic materials. Although CVD diamond-sheet tools have been on the market for several years, diamond-coated carbide inserts have become available only recently, with the successful resolution of long-standing adhesion problems. Diamond coating morphology on the rake surface of the tool affects chip formation favorably, whereas a microscopically rough, faceted morphology on the flank surface of the tool produces a rough workpiece finish. Workpiece finish can be improved by using a coated tool with a larger nose radius. The tool life provided by diamond-coated tools(~30 $\mu\textrm{m}$ thick) can meet or exceed that of PCD tools, depending on the characteristics of the workpiece material. When using diamond-coated carbide tools in milling, a sharp-edged PCD tool should be used in the wiper position of the cutter to minimize workpiece roughness and burr formation.

• 한국음향학회지
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• 제37권5호
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• pp.292-299
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• 2018

자동차 외장 디자인은 차량의 첫인상을 만들지만, 엔지니어링 입장에서는 공력 및 바람소리 성능에 중요한 요소이다. 외장 디자인은 차량의 프로토 타입 시점에 변경하기는 불가능하기 때문에 차량 초기 디자인 단계에서 외장 디자인을 점검하고, 바람소리 수준을 예측하는 것이 중요하게 된다. 외장 디자인 요소 중 차량 바람소리에 중요한 A필라와 와이퍼에 대한 바람소리 해석 기법은 개발되어 적용되고 있으나, 해석 및 모델링 과정이 복잡하고 시간이 많이 소모되기 때문에 엔지니어입장에서 디자이너 및 설계자와 함께 A필라 및 와이퍼 형상별 기여도를 검토하기엔 시간적인 여유가 부족하게 된다. 본 논문에서는 최적화를 위하여 A필라 형상 및 와이퍼 형상에 따라 바람소리 해석 S/W인 PowerFLOW(PowerClay 모델링 S/W, SEA-Baced(Statistical Energy Analysis-Based) 실내소음 해석툴, Turbulent Acoustic Power 해석툴)를 이용하여 실내소음을 해석적으로 예측하고, 예측한 결과를 이용하여 반응 표면법을 이용하는 최적화 S/W인 modeFRONTIER를 이용하여 디자인 요소에 대한 반응면을 구축하여, 디자인 요소와 실내 소음간의 상관성을 구성하여, 디자인 단계에서 A필라와 와이퍼에 의한 바람소리 수준을 예측하였다. 최적화 결과 및 반응면 구축 예측 결과에 대하여 실제 시험을 통하여 예측 경향성을 판단하고, 해석 및 예측에 대한 신뢰성을 확인하였다. 최종적으로 해석 및 반응면 구축 과정을 통하여 A필라 및 와이퍼에 대한 차종별 CAT(Computer Aided Test) 분석툴을 개발하고, 실제 차량 개발 과정에 적용하여 효용성을 확인하였다.

• 소음진동
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• 제9권4호
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• pp.841-848
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• 1999

직류 모터의 생산 공정품질 확인 작업에 있어서 전체 소음레벨이 합격점에 이른다 할지라도 관능 평가시의 이음으로 인해 불량판정을 받게되는 경우가 있다. 이런 종류의 문제는 가공 또는 조립 공정상에서 발생될수 있는데 본 눈문에서는 과도기적 스펙트럴 분석 혹은 시간-주파수 분석 기법을 소음품질 문제에 적용해 보았다.Case Study로써 윈드쉴드 와이퍼 모터의 이음 발생원이 상세 분석되었으며, 결과적으로 정상적인 주파수 분석에서 발견되지 않았던 아마추어 축의 불량이 충격소음을 일으킨것으로 밝혀졌다. 이를 통해 회전체-기어 시스템의 이음 원인규명을 위한 시간-주파수 분석 기법의 효과적 활용이 잘 나타났다.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2016년도 춘계 학술논문 발표대회
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• pp.255-256
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• 2016

In order to overcome the limitation of conventional cleaning method by workers, variety attempts to develop a window cleaning apparatus has been tried. However, the existing cleaning devices were lack of consideration for avoiding projection parts of the window such as frames or profiles. In this study, operating mechanism of cleaning tool for avoiding the projections parts using a two-axis robot is proposed. Proposed mechanism is that a wiper are reposed in a relatively stationary in the vicinity of the projection and avoided the projection in this state. It is expected that the mechanism is the base of driving cleaning tool part in the new window cleaning apparatus.

• 한국자기학회:학술대회 개요집
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• 한국자기학회 2013년도 자성 및 자성재료 국제학술대회
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• pp.95-95
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• 2013

The NdFeB magnet can be classified into the sintered magnet and bonded magnet. The former has superior magnet characteristics but the degree of freedom in shape is highly restricted, whereas the latter has a high degree of freedom, but its magnet characteristics are inferior to the former. When a NdFeB magnet is used at the elevated temperature, part of Nd must be replaced with a high priced Dy to increase its coercive force. For these reasons, a Dy free and high performance NdFeB bonded magnet is desired strongly. The author successfully developed a Dy free NdFeB anisotropic bonded magnet based on discovery of new phenomena called as d-HDDR reaction and its mass production process such as a thermally balanced hydrogen reaction furnace, micro capsuled powder, compression molding / injection molding under magnetic field, magnetic die and so on. Applied to DC brush seat motor for automotive use, the motor has become 50% small in size and weight. The commercialization of a half sized motor for automotive use has been realized up to the market share of 30%. At present, its commercialization is extending to various types of motors such as power tool, ABS motor, wiper motor, window motor, electric bike power motor, and compressor motor. It is expected that the applications will be increasingly enlarged to EV motor, wind generator, EPS motor, washing machine, and glass cutting machine. This innovative technology has realized Dy free high performance magnet and mudt make big contribution to not only rare element strategies but also energy conservation.