• 한국산학기술학회논문지
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• 제9권2호
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• pp.270-275
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• 2008

자동차용 직선 베벨기어는 대량으로 생산되고 있기 때문에 생산성 향상을 위해 기어가공용 전용기에서 직접 가공하던 것을 냉간 단조 제조방식으로 변경되어 생산되고 있다. 시행착오를 최소화하여 단조에 의한 정확한 최종 형상의 정밀 제품을 조기에 개발하고, 반복 재현성을 확보하는 방법으로 CAD/CAM 시스템의 도입이 필요하다. 본 연구에서는 CAD/CAM 시스템을 활용하여 크라운 치형을 갖는 직선 베벨기어를 모델링 한다. 이를 토대로 NC 데이터 생성과 검증을 통해 가공품을 사전에 예측을 한 후 물림시험의 결과를 통해 마스터 기어를 제작한다. 이러한 마스터기어를 통하여 금형제작이나 가공에 필요한 지그제작을 가능하게 한다.

• 한국공작기계학회:학술대회논문집
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• 한국공작기계학회 2000년도 추계학술대회논문집 - 한국공작기계학회
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• pp.169-174
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• 2000

This paper is about automatic design of measuring master gears. Master gears are usually thought of as gears of extreme accuracy level, but are better defined as gages to check the meshing action of production gears. This is usually not recognized because most mechanical gages are associated with static measurements rather than having the form of machine elements used in a functional check involving machine motion. In this paper the interface that allows beginners to design easily and quickly is provided. The addition and modification of data is easy and the reduced design lead time is feasible with the program even though users don't know much about program since it is developed with Visual Lisp and DCL.

• Tribology and Lubricants
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• 제23권4호
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• pp.149-155
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• 2007

The CAD model of a elliptical gear for wire cutting has been developed. The rolling contact of pitch ellipses whose rotation axes coincide with their focus has been analyzed, and the perimeter of the pitch ellipse has been divided into equal-length segments by the number of teeth. A master tooth profile, which is a composite curve of circular arcs that represents involute, has been introduced. The elliptical gear has been designed by imposing the master tooth on the divided points of the pitch ellipse, and a full fillet has been achieved between neighbour teeth. Thus, the whole profile of an elliptical gear is a composite curve of arcs only, and consequently NC codes for wire cutting can be easily generated. Furthermore, a computer simulation program is developed to verify the mesh of the elliptical gear.

• Tribology and Lubricants
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• 제24권5호
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• pp.221-227
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• 2008

This paper presents a step-by-step design of noncircular gears. From the diagram of angular velocity ratio of a noncircular gear pair, the pitch curves of the two mating gears are determined, and the perimeter of the pitch curve has been divided into equal-length segments by the number of teeth. A master tooth profile, which is a composite curve of circular arcs that represents involute, has been introduced. A noncircular gear pair has been designed by imposing the master tooth on the divided points of the pitch curve, and a full fillet has been achieved between neighbour teeth. Thus, the whole profile of the noncircular gear is a composite curve of arcs only, and consequently NC codes for wire EDM can be easily generated.

• 대한기계학회논문집A
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• 제34권2호
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• pp.237-243
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• 2010

본 논문은 자동차 변속기의 헬리컬기어 검사 장치에 대한 것이다. 기어 프로파일 전용 검사설비는 시간이 많이 소요되므로 생산라인용으로 적합하지 못하다. 본 논문에서 사용된 마스트기어를 이용하여 생산된 기어와 비교하여 방법은 보다 경제적이며 효율적이다. 본 논문에 사용된 3가지 기어검사 파라미터는 nick, 흔들림(run-out) 및 PCD (pitch circle diameter) 등이다. 기어검사장치의 측정정밀도에 영향을 미치는 요소들에 대해서도 또한 언급되었다. 이 장치는 현재 국내에서 전량 수입되는 기어 생산라인용 설비에 실제적으로 사용될 것이다.

• 대한기계학회논문집A
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• 제28권5호
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• pp.624-631
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• 2004

In this paper, new replication techniques fur a metal microcomponent having a real 3D shape were introduced. Helical gear was selected as one of a real 3D microcomponents for this study. The helical gear, which was made of photo-curable resin, was fabricated as a master pattern by microstereolithography technology. Then, a silicone rubber mold was fabricated from the master pattern. Lastly, a final bismuth alloy pattern was transferred from the silicone rubber mold by the microcasting process. In this paper, the replication technique is described in detail from the master pattern to the final pattern with some investigation on factors related to the technique.

• 대한기계학회논문집A
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• 제36권5호
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• pp.555-561
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• 2012

자동차 변속기 내부에서 동력을 전달하는 헬리컬 기어의 소음 및 진동을 억제하기 위한 하나의 방법으로 정밀하게 가공된 기어를 검사하기 위한 방법에 관한 것이다. 본 연구에서는 측정 기준이 되는 표준 기어와 측정 대상 기어인 워크 기어를 정밀하게 측정하는 알고리즘에 관한 것이다. 기존의 방법은 표준 기어와 모니터 기어를 1회전하여 주파수 방법으로 측정 표준을 위한 마스터링 작업을 수행하였다. 본 연구에서는 제시된 알고리즘을 사용하여 표준 기어와 모니터 기어를 측정하고, 표준 기어와 모니터 기어의 오차를 계산하는 방법을 제시함으로써 기어 측정에 대한 정밀도를 높이도록 하였다. 또한 본 알고리즘을 사용하면 빠른 속도로 측정의 표준이 되는 마스터링 공정을 빠르고 정확하게 측정할 수 있을 것으로 예상된다.

• 수산해양기술연구
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• 제47권1호
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• pp.37-45
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• 2011

Reduction of ship's rolling is the most important performance requirement for improving the safety of the crew on board and preventing damage to cargo as well as improving the comfort of the ride. It is a common experience for mariners, to see that steering with a rudder generally induces rolling of the ship, though the original aim of the rudder is to keep the ship's heading to the required course. At the first stage, when a rudder is steered, usually a ship heels in an inward direction, due to the roll moment acting on the rudder. At the next stage in steering, the main heel may change to an outward. This coupling between rudder and roll motion has become an attractive problem from the point of view of roll stabilization using the rudder, because it is a natural in sight that if the rudder action is skillfully related to the change of roll as well as to the course deviation, the roll can be reduced to a certain degree. The main aim of this paper is to discuss the results of the actual full-scale sea trials carried out on steer gear No.1 and No.1 2, the individual quartermaster and to make clear their statistical properties, using the actual data which included measurement of roll angle, roll rate and the comparative tests were carried out immediately after each other, in order to minimize any statistical variation in sea conditions. It can be concluded that the steer gear No. 1 2 reduced the roll motion on average by about 21% in comparison with the No.1 and confirmed the some difference as per a ability of quarter-master's maneuver.

• 한국생산제조학회지
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• 제9권1호
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• pp.30-37
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• 2000

In this paper rapid prototyping and precision casting technology have been developed for the manufacturing of inlet gear box of an airplane, Rapid prototyping is a new prototyping technology that produces complicated parts directly from three-dimensional CAD data with a high efficiency and has been extensively applied to various manufacturing processes. In the present work Selective Lase Sintering(SLS) system is utilized in order to manufacture prototype of the inlet gear box. Prototyping technology using SLS is also investigated from the viewpoint of accuracy. Using the SLS master the casting products are manufactured through several processes such as : vacuum casting lost wax shell casting and investment cast-ing. The shrinkage characteristics of wax and cast iron in the casting procedures are considered and then reflected to the design procedure so that the accuracy of the product is improved consequently.

• 열처리공학회지
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• 제27권4호
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• pp.191-201
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• 2014

The gear was made of SNC815 case-carburized, quench hardened and tempered steel. The gears were failed far earlier than the expected service life used in the industrial site. Causes of the failed gear were analyzed by microstructure observation. By the SEM and micro structure examinations, the damaged surfaces had been weared and failed by fatigue. Through microscope observation on the damaged surface, it was found that the cause of failure was determined by external overloading and the initial stage of the damage was closely related to complex contact fatigue failure. The overload and contact fatigue contributed to the early failure cause.