• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 1999.10a
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• pp.63-68
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• 1999

Because misaligned shafts have caused noise, vibration, bearing failures, and stress concentration of coupling part, which decrease the efficiency and life of a shaft system, the proper alignment of shaft system should be monitored continuously in dynamic condition. To solve these problems under dynamic condition, a telemetry system is this study is used to find the condition of the least bending moment, which is known by analyzing the structure and stress induced by misalignment is investigated. The moment derived from two shaft strain at the nearby coupling is measured. The bending strain is measured 5 times for average in static state as well as dynamic state with 100~700 rpm.

• Journal of the Korean Society for Precision Engineering
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• v.25 no.8
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• pp.72-79
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• 2008

To meet demand of big capacity and high speed rotation for washing machine, more stress from bending and twisting are complexly loaded onto the shaft supporting the horizontal drum, causing problems in fracture strength and fatigue life. Shafting system is mainly divided into flange and shaft. Shaft and flange connected by inserting shaft serration into flange on the process of die casting. When the system is operating, the gap is formed between serration and flange. But, Serration has various design factors and the optimal values can't be easily determined. Using a design of experiment (DOE) based on the FEM (Finite Element Method), this study was performed investigating the interaction effect between the various design factors as well as the main effect of the each design factor under bending, twist and vibration and proposed optimum design using box-behnken method among response surface derived from regression equation of simulation-based DOE.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.9 no.4
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• pp.859-864
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• 2008

The dynamic interaction between the moving mass and the rotating Timoshenko shaft is investigated. The moving speed of the mass is presented by a constraint equation related to the rotating speed of the shaft. The dimensionless equations of motion for the rotating shaft with a moving mass by using the Timoshenko's beam theory. The dynamic responses of this system are studied. influences of dimensionless parameters such as the rotating speed ratio. the Rayleigh coefficient and the dimensionless axial force are discussed on the transient response and the maximum deflection of the moving system.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.17 no.12
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• pp.1201-1207
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• 2007

The Timoshenko beam theories are used to model the rotating shaft. The nondimensional equations of motion for the rotating shaft subjected to moving mass and compressive axial forces are derived by using Hamilton's principle. Influence of system parameters such as the speed ratio. the mass ratio and the Rayleigh coefficient is discussed on the response of the moving system. The effects of compressive axial forces are also included in the analysis. The results are presented and compared with the available solutions of a rotating shaft subject to a moving mass and a moving load.

• Journal of the Korean Society for Precision Engineering
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• v.29 no.12
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• pp.1351-1359
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• 2012

Due to the development of electric and hybrid vehicles, the trend has changed from hydraulic power steering system to electric power steering system (EPS). In this paper, design parameters are deduced through the structural analysis based on the finite element analysis for the intermediate shaft of the EPS on the market. By analyzing the design parameters, the structure design is improved to support the required high torque on the EPS. The numerical analysis is performed to obtain the improved design of the intermediate shaft model and the analysis results are compared with the existing model. It is noted through this numerical approach that the improved design of the intermediate shaft can be acquired the structural safety and high stiffness than existing model.

• Smart Structures and Systems
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• v.2 no.1
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• pp.47-60
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• 2006

Bi-spectrum is a tool in the signal processing for identification of non-linear dynamic behvaiour in systems, and well-known for stationary system where components are non-linearly interacting. Breathing of a crack during shaft rotation is also exhibits a non-linear behaviour. The crack is known to generate 2X (twice the machine RPM) and higher harmonics in addition to 1X component in the shaft response during its rotation. Misaligned shaft also shows similar such feature as a crack in a shaft. The bi-spectrum method has now been applied on a small rotating rig to observe its features. The bi-spectrum results are found to be encouraging to distinguish these faults based on few experiments conducted on a small rig. The results are presented here.

• Proceedings of the KSME Conference
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• 2007.05a
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• pp.1031-1036
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• 2007

Torsional vibration analysis is necessary at design stage to ensure the reliability of a system particularly when the driven machine is a reciprocating compressor. This paper contains the results of torsional vibration analysis and fatigue strength evaluation for 540 kW compressor driving motor. Torsional vibration analysis showed that the $2^{nd}$ torsional mode of the entire shaft system has the possibility of resonance with the $14^{th}$ order excitation of compressor and twin line frequency of motor at operating speed. Therefore, the analyses were required to ensure the structural reliability of the motor. The fatigue strength was evaluated for the shaft and inner fans using the results of forced vibration analysis. It is concluded that the motor has sufficient fatigue strength under normal operating condition.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.9 no.4
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• pp.147-153
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• 2000

This paper presents a design method using CAE(Computer Aided Engineering ) with the consideration of reliability for optimal gear driving system. This method considered a configuration of the intermediate shaft. There are four mounting types, such as double straddle, double overhung, output gear overhung, and input ger overhung in the intermediate shaft. The reliability and life analysis are based on the two-parameter Weigbull distribution lives of the gears and bearing . The validity and feasibility of the proposed method are verified by the application to transmission of a industry machine.

• Proceedings of the Korean Society of Marine Engineers Conference
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• 2006.06a
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• pp.311-312
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• 2006

선박의 추진축은 선박의 기관실 최말단부에서 바깥의 프로펠러까지 선체를 관통하여 설치되고 회전하기 때문에 선외로부터의 해수유입을 쳐대한 차단하는 역할을 하는 독특한 메커니즘을 가진 축밀봉장치(Shaft Sealing System)를 필요로 하는데 이것을 스턴튜브 씰(Stem Tube Seal)이라고 한다. 본 연구는 국내 중소형 선사들이 저렴한 가격대비 우수 품질의 씰 및 하우징을 사용할 수 있고 3차원 형상화를 통하여 선박의 운용자가 쉽고 정확하게 스턴튜브 씰을 이해 및 신속 정비가능, 해외업체 생산 규격을 선박 축에 맞게 절단, 접합의 씰 성능저하 관행을 고쳐 선주가 원하는 사양과 규격대로 제작된 우수한 씰 제품을 공급할 수 있고, 선박용 기자재에 대한 기초지식, 씰링 메카니즘, 구조 및 유동 해석 결과를 제공하여 국내 최초의 무접착 원형 메인 씰 개발 및 씰 하우징 제작 및 독자설계 기술을 확립하고자 한다.

• Journal of KSNVE
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• v.10 no.4
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• pp.623-628
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• 2000

This paper presents the automatic plumbness measuring system form improving the accuracy and working time for plumbness measuring of semi-umbrella type hydraulic turbine generator. It is general practice that rotating shaft should run within acceptable vibration limit. In order to obtain more accurate measuring data for single stage shaft on the semi-umbrella type, plumbness approach must be established carefully and accurately. Generally, present plumbness procedure is required several calculation algorithm, laser sensor and data acquisition devices. As a result of application to actual new system it is confirmed that working time could be saved over 80% and accurate measurement data could be acquired.