• Proceedings of the Korean Society of Precision Engineering Conference
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• 1993.04b
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• pp.86-91
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• 1993

연삭숫돌은 드레싱에 의해 초기숫돌면의 상태가조정되며, 가공과 더불어 공작물과 연삭숫돌의 연속적인 간섭으로 공작물의 치수변화와함께 연삭숫돌도 작업면이 변화하게 된다. 공작물의 표면은 연삭조건 및 공작물과 숫돌의 접촉특성에 따라 Rubbging, Ploughing, Cutting 작용이 이루어져 가공면이 형성되며 이때의 공작물의 표면 품위( Surface Integrity)는 연삭숫돌의 상태변화에따라 매우 민감하게 영향을 받는다. 본 연구에서는 원통연삭작업 에서의 감시 및 진단기술개발을 위하여 AE 센서의 적용가능성을 살펴보기위하여, 센서의 설치위치에 따른 영향 및 연삭가공 특성을 잘나타내는 AE Parameter의 선정을 위한 실험을 수행하며, 가공시간에 따른 연삭숫돌작업면 의 상태변화에 의한 AE Parameter의 변화를 조사하며, 이와더불어 연삭중의 법선저항을 측정분석하고 통계적인 수법으로 ARMA (Autoregressive Moving Average)을 이용하여 가공특성변화를 분석한다.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2004.05a
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• pp.318-318
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• 2004

원통 연삭기(cylindrical grinding machine)는 원통형 공작물을 센터나 척으로 지지하면서 연삭 공정을 수행하기 때문에 연속적인 작업이 어렵지만, 무심 연삭기(centerless grinding machine)는 원통형 공작물을 받침판으로 지지하면서 연삭 숫돌(grinding wheel)과 조정 숫돌(regulating wheel)로 연삭 공정과 축방향 이송을 동시에 수행하기 때문에 연속적인 작업이 가능하다. 특히 고정밀 부품을 작업자의 숙련도와 무관하게 고능률적으로 가공할 수 있는 무심 연삭기는 구름 베어링, 축, 피스톤 핀 등과 같은 고정밀 기계류 부품들을 대량 연삭하기 위한 용도로 많이 사용되어 왔다.(중략)

• Journal of the Korean Society for Precision Engineering
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• v.23 no.1 s.178
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• pp.193-200
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• 2006

To perform the finish grinding process of ferrules which are widely used as fiber optic connectors, a high-precision centerless grinding machine is necessary. The high-precision centerless grinding machine is consisted of the hydrostatic GW and RW spindle systems, hydrostatic RW feeding mechanism, RW swivel mechanism, on-machine GW and RW dressers, and concrete-filled steel bed. In this study, the thermal characteristics of the high-precision centerless grinding machine such as the temperature distribution, temperature rise and thermal deformation, are estimated based on the virtual prototype of the grinding machine and the heat generation rates of heat sources related to the machine operation conditions. The reliability of the predicted results is demonstrated by the temperature characteristics measured from the physical prototype. Especially, the predicted and measured results show the fact that the high-precision centerless grinding machine has very stable thermal characteristics.

• Journal of the Korean Society for Precision Engineering
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• v.22 no.2
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• pp.172-179
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• 2005

A high-precision centerless grinding machine has been recognized as a core equipment performing the finish outer-diameter grinding process of ferrules which are widely used as fiber optic connectors. In this study, in order to realize the high-precision centerless grinding machine, the structural characteristic analysis and evaluation are carried out on the virtual prototype consisted of the steel bed, hydrostatic GW and RW spindle systems, hydrostatic RW feed mechanism, RW swivel mechanism, and on-machine GW and RW dressers. The loop stiffnesses of centerless grinding machine are estimated based on the relative deformations between GW and RW caused by the grinding forces. And the simulated results illustrate that the concrete-filled bed has the considerable effect on the improvement of the structural stiffness of centerless grinding machine.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2005.06a
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• pp.90-95
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• 2005

To perform the finish outside-diameter grinding process of ferrules which are widely used as fiber optic connectors, a high-precision centerless grinding machine is necessary. In this study, the thermal characteristics of the high-precision centerless grinding machine such as the temperature distribution, temperature rise and thermal deformation, are estimated based on the virtual prototype of the grinding machine and the heat generation rates of heat sources related to the machine operation conditions. The reliability of the predicted results is demonstrated by the temperature characteristics measured from the physical prototype. Especially, the predicted and measured results show the fact that the high-precision centerless grinding machine consisted of the hydrostatic GW and RW spindle systems, hydrostatic RW feeding mechanism, RW swivel mechanism, on-machine GW and RW dressers, and concrete-filled steel bed, has very stable thermal characteristics.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.30 no.12 s.255
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• pp.1634-1641
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• 2006

High-precision centerless grinding machines are emerging as a means of finishing the outer diameter grinding process required for ferrules, which are widely used as fiber optic connectors. In this study, a sensitivity analysis for structural and thermal characteristics was carried out using a virtual prototype of a centerless grinding machine to realize systematic design technology and performance improvements required to manufacture ferrules. The prototype consisted of a concrete-filled bed, hydrostatic grinding wheel (GW) and regulating wheel (RW) spindle systems, a hydrostatic RW table feed mechanism, a RW swivel mechanism, and on-machine GW and RW dressers. The results of the structural sensitivity analysis illustrated that the vertical stiffness of hydrostatic guideway for the RW table feed system greatly influenced the horizontal loop stiffness, and the results of the thermal sensitivity analysis illustrated that the heat generation rates at hydrostatic bearings and belt pulley greatly influenced the temperature rise of hydrostatic bearings and the deviation of thermal displacement between GW and RW.