• 한국분말야금학회:학술대회논문집
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• 한국분말야금학회 2006년도 Extended Abstracts of 2006 POWDER METALLURGY World Congress Part2
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• pp.752-753
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• 2006

Oil Pump rotor is essential parts for automobile and, it is consisted of drive rotor and driven rotor in general. These parts are requested different properties according to environment. There are 2 types of Oil Pump rotor according to its usage. One is used for electric system, and the other is used for shaft-driven system. Especially, high precision and functionality is required in electric pump, and cost reduction is required in shaft-drive pump without slowing down its performance. This paper is mainly describing about the non-machine treated shaft-drive pump, based on the trial sample producing process.

• 한국기계가공학회지
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• 제17권4호
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• pp.32-38
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• 2018

In this study, the one-piece propeller shaft composed of carbon/epoxy was designed and manufactured for 4 wheel drive automobiles that can bear the target torsional torque performance of 3.5kN.m. For the CFRP tube, braiding machine was used to weaving carbon fiber and it was formed the braided yarns with the braid angle ${\pm}45^{\circ}$ and axial yarns to improve strength of the lengthwise direction. The final CFRP tube of propeller shaft was evaluated through the torsional torque test. The CFRP propeller shaft satisfied requirement of the target torsional maximum torque of 3.5kN.m. Also, it was found that the one-piece composite propeller shaft with CFRP tube had 30% weight saving effect compared with a two-piece steel propeller shaft.

• 한국소음진동공학회논문집
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• 제25권6호
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• pp.377-383
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• 2015

Torsion mode or bending mode of drive-line for rear-wheel drive vehicle exists in low frequency band. If resonance exists there between natural mode of driveline and powertrain excitation force, drive-line will manifest excessive vibration response. Also, the vibration response can be transmitted to vehicle body and can induce booming noise. A vehicle in this study exhibits a booming noise problem under specific transmission gear condition. To draw performance improvement plan, finite element analysis technique was used. Modification was evaluated qualitatively and priorities were derived. Finally, effectiveness of best modification was verified through test and full vehicle FE analysis.

• 한국생산제조학회지
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• 제24권3호
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• pp.278-286
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• 2015

The effects of the main bearing stiffness combined with vertical non-torque force on the input load and shaft deflection of a gearbox were investigated for the three-point suspension drive train of a wind turbine. A finite element analysis model for the drive train was studied experimentally, and its applicability to the present study was verified. The results show that, as the main bearing stiffness is increased, the input load of the gearbox decreases, whereas the input shaft deflection increases. The stiffness component for the pitch moment has the largest influence on the gearbox input load. Although the gearbox life increases at a higher main bearing stiffness, the economic efficiency and durability of the entire drive train system should also be considered in the selection of the main bearing stiffness.

• 한국기계가공학회지
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• 제18권6호
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• pp.45-54
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• 2019

In this study, we analyze the rattle noise of a power takeoff (PTO) driveline and develop a PTO driveline resonance model. We measured the rattle noise of the PTO driveline on the output shaft and, by analyzing the rattle noise in the time domain, we determine that the engine expansion stroke period matches the sound pressure of rattle noise. This finding helped us demonstrate that the rattle noise is caused by the collision between the PTO driving gear and the gear driven by the engine expansion stroke; the torsional vibration caused by this collision is affected by the angular velocity fluctuation of the PTO drive shaft. By measuring the angular velocity of the PTO drive shaft, we confirm that the angular velocity fluctuation of the engine flywheel tends to excessively amplify the PTO drive shaft angular velocity fluctuation. We conclude that the resonance, which occurs when the operating frequency of the engine is close to the natural frequency of the tractor power transmission system, causes the excessive angular velocity fluctuation of the PTO drive shaft. We performed a modal analysis of the PTO driveline resonance and, using the characteristic equation, we show that the resonance occurs when the engine rotation speed is close to 850 rpm, which matches the natural frequency of the PTO driveline.

• 한국복합재료학회:학술대회논문집
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• 한국복합재료학회 1999년도 추계학술발표대회 논문집
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• pp.49-52
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• 1999

Substituting composite structures for conventional metallic structures has many advantages because of higher specific stiffness and specific strength of composite materials. In this work, one-piece propeller shafts composed of carbon/epoxy composite and glass/epoxy one were designed and manufactured for a rear wheel drive automobile, which uses generally a steel two-piece propeller shaft. From the tests of the composite propeller shafts, it was found that the propeller shafts satisfied requirements of static torque transmission capability, torsional buckling capability and the first natural bending frequency and had 40% weight saving effect compared with steel propeller shaft.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2001년도 춘계학술대회논문집B
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• pp.361-365
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• 2001

Laboratory tests are conducted to validate the mechanical model of a filament-wound composite shaft. Also, design charts are produced by validated analytical calculations based on the Timoshenko beam model of a layered steel/composite structure. The major results found are that steel/composite hybrid shafts can lead to better dynamic and static performances over steel or pure composite shafts of the same volume, and the most effective composite structures contain some steel in the form of a tubular core. These results can be used in the design process of composite boring bars and automotive drive shafts.

• 드라이브 ㆍ 컨트롤
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• 제15권1호
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• pp.16-27
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• 2018

Hydraulic torque load simulator is essential to test and qualify the performance of various angle control systems. Typically a flapper-type second stage servovalve is applied to the load simulator, but here the direct drive servovalve, which is a kind of one-stage valve and affected by the large flow force, is applied. Since the torque load is applied not to the stationary shaft but to the rotating shaft of the angle control system, the controlled torque of load simulator is not accurate due to the rotating speed of the angle control system. A feedforward compensator is designed and applied to minimize the disturbance-like effect. A mathematical model is derived and linearized to analyze the stability, accuracy and responsiveness of the torque load simulator. The parameter effects of a controller, servovalve, hydraulic motor, rotating spring shaft are analyzed and summarized. The goodness of the linear analysis is verified by the digital computer simulations using both the linear and nonlinear mathematical models.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2012년도 춘계학술대회 논문집
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• pp.292-293
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• 2012

• 대한기계학회논문집A
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• 제40권8호
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• pp.759-765
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• 2016

항공기 등에 사용되는 Flexible PTO(Power Take-Off) 샤프트는 스프링 특성을 좋게 하기 위해 여러장의 얇은 멤브레인을 용접한 형태로 1950년대에 이미 개발됐으며, AMAD(Aircraft Mounted Accessory Drive) 기어박스와 EMAD(Engine Mounted Accessary Drive) 기어박스 사이에서 회전동력을 전달한다. 이런 종류의 샤프트는 가볍고 특히 스프링 특성이 좋기 때문에 축 정렬이 틀어진 고속회전 상태에서도 안정적으로 회전동력을 전달할 수 있어 대부분의 전투기에 사용된다. 이번 연구에서 티타늄 합금으로 개발된 Flexible PTO 샤프트의 구조해석을 통해 제품의 안전성을 확인하였고, 실제 실험실에서 진행된 고속회전 시험에서 굽힘과 비틀림 부하를 동시에 인가하여 샤프트의 고주기 피로에 대한 내성을 실증하였다. 또한, 고주기 피로 시험 조건에서 항공기용 볼 조인트의 마모 특성 분석을 통해 수명을 예측하였다.