• 한국추진공학회지
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• 제12권4호
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• pp.7-15
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• 2008

항공기 제작 시 중요한 요소는 항공기 구조의 안전성과 경량화라 할 수 있다. 자긴가공 공정을 통하여 고압의 항공기 부품을 신뢰성 증대와 함께 재료의 경량화도 같이 얻을 수 있다. 이 방법은 주로 단일 실린더에 적용되었다. 그러나 바우싱거 효과에 의하여 자긴가공의 유용함이 줄어든다. 바우싱거 효과를 줄이기 위한 억지 끼워맞춤과 자긴가공을 이용한 복합실린더에 대한 관심이 증대하고 있다. 본 연구에서 동일한 치수를 가진 단일 및 복합실린더를 고려하였다. 복합실린더에서 억지 끼워맞춤에 의하여 경계면에서 낮은 압축 잔류응력이 유도되며, 내경에서 보다 낮은 소성 변형률이 유도된다. 이는 바우싱거 효과를 줄여, 내경에서 더욱 유용한 잔류응력을 얻을 수 있음을 의미한다.

• 한국정밀공학회지
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• 제27권9호
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• pp.94-102
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• 2010

The spindle is the main component in machine tools. To develop high speed machine tools, a lot of studies have been carried out for high speed spindle. Bearing is very important part in spindle. The bearing clearance is influenced by shrink fit and thermal expansion during operation. The designer must take into account the reduction of shrink fits. The aims of this study are to grasp the shrink fits and behavior of a bearing which is a deeply connected with fatigue life of bearing and performance of spindle through FEM(Finite Element Method). This paper proposed optimum value of shrink fit considering deformation of spindle and stress of fitting area using design of experiments. Thus, the proposed formula can be used to obtain bearing internal clearance.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2010년도 춘계학술대회 논문집
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• pp.449-450
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• 2010

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2010년도 추계학술대회 논문집
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• pp.349-350
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• 2010

• 한국소음진동공학회논문집
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• 제16권5호
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• pp.441-451
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• 2006

It is known that ball bearings mounted in housing or on shaft are playing a key role to keep it running smoothly. The roundness of a housing bore on which bearing outer ring is mounted with interference has directly affected the running accuracy of bearing. The running accuracy of bearing, therefore, can extend the significant influence to the rotating machinery as well. In this paper, bearing's vibration and fatigue life considering raceway roundness of ball bearing before and after mounted in housing bore are theoretically estimated. To perform analysis, a simple three degrees of freedom model was proposed and then Newton-Raphson iterative method was introduced to be utilized in the analysis. The results show that the vibration magnitude of ball bearing fitted into housing unit is appeared considerably larger than the one of its pre-assembling. And theoretical $L_{10}$ life which ninety percent of the bearing population will endure decreased in about fifty percent.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2008년도 춘계학술대회 논문집
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• pp.238-241
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• 2008

A brake system in automobile is one of the important parts that directly affect the safety of passengers. Particularly, disk brake module is applied to almost all kinds of automobile brake system due to its remarkable braking power and braking distance. In the disk brake module of an automobile, the bolt for tire wheel is assembled to the disk brake hub by interference fit (bolt pressing process). The process induces small deformation whose range is within tens of ${\mu}m$ and this deformation may cause the runout badness of the whole disk brake module, and even braking problems such as judder or squeal phenomena which makes the loss of braking efficiency. In this study, bolt pressing fit into hub was simulated by $ANSYS^{TM}$, a commercial structure analysis program. Also, the aspect and the cause of hub displacement were analyzed and the solution for decreasing runout of hub was proposed.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2005년도 추계학술대회논문집
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• pp.112-118
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• 2005

Ball bearings which were fitted between housing and shaft play an important role in rotating shaft system smoothly, Therefore bearing's running accuracy has significant influence on that of rotating machinery. Manufacturing accuracy of bearings as well as that of shaft and housing is main factor to affect bearing running accuracy In this paper, bearing's vibration and fatigue life considering raceway roundness of ball bearing before and after being fitted into housing are theoretically estimated. To perform analysis, a simple three degrees of freedom model was proposed and then these analysis was conducted utilizing the Newton-Raphson iterative method. The results show that vibration magnitude of ball bearing fitted into housing is considerably larger than before assembly, and bearing's theoretical L$_{10}$ fatigue life that ninety percent of the bearing population will endure decreased in about fifty percent.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2006년도 추계학술대회 논문집
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• pp.241-242
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• 2006

• 항공우주기술
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• 제13권2호
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• pp.167-176
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• 2014

유로의 개폐를 위해 사용되는 파이로밸브는 가볍고 신뢰성이 높은 장점을 가진다. 미국에서는 하이드라진 추진제를 사용하는 일부 위성 유실의 원인을 착화기 연소 가스의 누설로 판단하였고, 블로우바이라 불리는 이러한 누설 문제를 방지하기 위하여 억지끼워맞춤을 하는 피스톤을 개발하고 추가적인 설계변경을 통하여 신뢰성을 향상하였다. 여기서는 미국에서 수행된 파이로밸브 연구에 대한 문헌조사를 AIAA Paper 위주로 수행하였다. 또한 파이로밸브의 일반적인 문제점과 개선방향, 성능비교평가 사례 등을 다루었다.

• 대한기계학회논문집A
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• 제26권8호
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• pp.1615-1622
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• 2002

The purpose of this study is comparing cold expansion method with interference fit. Cold expansion method and interference fit of fastener hole is using in the aerospace industry. These treatment lead to an improvement of fatigue life to the compressive residual stresses developed on the hole surface. But Research is nothing to about difference effect of between cold expansion method and interference fit. So, this paper, it is shown that Comparing cold expansion method with interference fit using the finite element method. It is further shown that residual stress distribution according to plate thickness and clamping force.