• 한국가스학회지
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• 제19권3호
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• pp.49-53
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• 2015

이 논문의 목적은 자동차 클러치, 수동변속기와 타이어 시스템의 마찰에 관련된 화재에 대한 고장사례를 분석하고 연구하는 것이다. 첫 번째 사례는 반복적으로 클러칭하면서 자동차의 클러치 디스크가 플라이 휠의 접촉면과 접촉하면서 열에 의해 과열되어 이 열이 수동변속기의 외부로 흘러 고착된 오일 찌꺼기에 옮겨 붙어 화재가 발생된 것으로 확인되었다. 두 번째, 사례로 변속 장치는 기어와 기어의 접촉에 의해 동력을 전달한다. 변속기 오일이 변속기 케이스의 균열로 인해 오일 부족 현상이 일어나 변속기 케이스 상단의 퇴적물에 의해 화재가 발생된 것을 확인하였다. 세번째 사례는 건조한 구덩이에서 빠져나오려고 반복적으로 가속페달을 작동시키면서 타이어와 도로의 마찰이 반복되면서 내부의 축적된 열에 의해서 화재가 발생된 것으로 확인되었다. 따라서, 운전자는 운전 중 마찰부에 화재가 발생하지 않도록 세심하게 관리하여야 한다.

• 한국자동차공학회논문집
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• 제12권4호
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• pp.101-109
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• 2004

Three models with various degree-of-freedom for a manual transmission clutch full-size tester have been developed and the models' reliability and accuracy have been verified using the measured data. A simulation study has also been conducted to understand dynamic behavior of the tester. The model for this simulation study includes clutch disk friction and damper dynamics. The developed model is very accurate in terms of maximum torque exerted on the clutch, slip duration and the vibration response except a slight difference compared to the measured data. In a history graph of the clutch torque, the maximum torque response from simulation is flat but the measured is sunken with a noticeable curvature. This phenomenon is found to be irrelevant to the dynamics of the full-size tester but is originated from the characteristics of the clutch itself. Thus, the full-size tester has been proven to be a reliable tester for clutch's power and torque transmission capability. To obtain a better understanding of clutch's characteristics and relationship between full-size tester and other testing methodologies, future research directions have been suggested.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2008년도 추계학술대회논문집
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• pp.105-111
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• 2008

The clutch with torsional damper is installed on a passenger car with manual transmission, which not only transmits the power generated by engine to the transmission but also absorbs the shock and vibration from the engine. The torsional damper in the clutch dissipates the torsional vibration energy and eliminates the resonance in the driveline but high damping in the damper causes the increase of the vibration level which is against the comfort and durability. In this study, a dynamic model for the passenger car driveline with manual transmission was developed to investigate the vibration and the effects of characteristics of the driveline. With the dynamic model, the vibration characteristics of driveline were examined by the mode analysis and driving simulation, and the effects of hysteresis torque and spring constant were investigated. The vehicle tests with prototype torsional dampers were preformed and the test results showed good agreements with the simulation.

• 한국소음진동공학회논문집
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• 제19권3호
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• pp.243-250
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• 2009

The clutch with torsional damper is installed on a passenger car with manual transmission, which not only transmits the power generated by engine to the transmission but also absorbs the shock and vibration from the engine. The torsional damper in the clutch dissipates the torsional vibration energy and eliminates the resonance in the driveline but high damping in the damper causes the increase of the vibration level which is against the comfort and durability. In this study, a dynamic model for the passenger car driveline with manual transmission was developed to investigate the vibration and the effects of characteristics of the driveline. With the dynamic model, the vibration characteristics of driveline were examined by the mode analysis and driving simulation, and the effects of hysteresis torque and spring constant were investigated. The vehicle tests with prototype torsional dampers were preformed and the test results showed good agreements with the simulation.

• International Journal of Automotive Technology
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• 제8권5호
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• pp.599-603
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• 2007

An efficient optimum design process has been developed and applied to systematically design a lock-up clutch system for a torque converter used in an automatic transmission. A simulated annealing algorithm was applied to determine the parameters of the compressive helical damper springs in the clutch. The determination of the number, location, a number of turns, and deflection of damper springs plays an important role in reducing vibration and noise in the lock-up system. Next, FE-based shape optimization was coded to find the shape of the clutch disk that would satisfy the strength, noise and vibration requirements. Using the optimum code, parametric studies were performed to see how spring diameters and frequencies of clutch systems changed as the damper spring traveling angles and the torques were varied. Based on the optimum results, five different designs for clutches with different springs were fabricated and vibration analyses and tests were conducted to validate the accuracy of the proposed method. Results from the two methods show a good correlation.

• 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.

• 항공우주시스템공학회지
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• 제17권1호
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• pp.10-15
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• 2023

덕티드팬의 동력절환장치인 클러치의 마찰판 사양을 최적설계하고 그 결과를 분석하였다. 클러치는 기계적 잠금장치의 적용 여부에 따라 2가지 방식으로 구분하고 각자의 설계 조건 하에 최적화 되었다. 클러치를 최적 설계하기 위한 인자로 전달토크 용량, 마찰재 면압, 마찰면의 온도 및 드래그 토크 등을 계산하였고, 클러치 분리판의 부피와 드래그 토크의 최소화를 최적설계의 목적함수로 활용하였다. 기계적 잠금장치가 포함되지 않은 Type 1의 경우 덕티드팬의 피치각에 상관없이 클러치의 작동이 가능하지만, 기계적 잠금장치가 포함된 Type 2에 비해 마찰면의 외경이 약 2배정도 증가하였고, 부피는 약 5~7배, 드래그 토크는 약 7~12배 정도 증가하였다.

• 한국기계가공학회지
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• 제3권1호
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• pp.84-89
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• 2004

This study is a basic one for application of ER Fluid to fluid power systems. By mixing silicone oil with zeolite particles, four kinds of ER fluids were made, in which the weight ratio of zeolite particles are different. We examined how the Yield shear stress and Bingham characteristics of the ER fluids are effected by varying electric field intensity. We designed and constructed a disk type power transmission clutch in which ER fluid fills and this ER fluid transmits the power of drive shaft to the driven shaft. With this equipment, the revolution transmission ratio from the chive shaft to the driven shaft by varying electric field density of the ER fluid was examined.

• Journal of Biosystems Engineering
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• 제40권2호
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• pp.95-101
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• 2015

Purpose: During the start-up period, the response time of a hydraulic system increases in the winter because of the increased oil viscosity caused by the cold weather. The problems of delayed tractor starting and excessive wear of the clutch disk occur for these reasons. Therefore, this study develops an analysis model using the commercial hydraulic analysis program AMESim to examine the characteristics of delays in power shuttle starting at different oil temperatures. Methods: In the experiment, a tractor was stationary on a flat surface with the engine running at a constant speed of 1,080 rpm. The forward lever was then pressed to activate the power shuttle at three different oil temperatures, and the pressure changes were measured. The pressure on the forward clutch control valve was measured by a pressure gauge installed on the hydraulic line supplied to the transmission from the main valve. An analysis model was also developed and verified with actual tests. Results: The trend of the simulated pressures of the power shuttle is similar to that of the measured pressures, and a constant modulation period was observed in both the simulation and test results. However, the difference found between the simulation and test results was the initial pressure required to overcome the initial force of the clutch spring. Conclusions: This study also examines the characteristics of the delayed startup of the power shuttle at different oil temperatures through simulations.

• 드라이브 ㆍ 컨트롤
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• 제12권1호
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• pp.1-8
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• 2015

The stability of friction characteristics and thermal management for a dry type dual clutch transmission (DCT) are inferior to those of a wet clutch. Too high temperature resulting from frequent engagement of DCT speeds up degradation or serious wear of the pressure plate or burning of the clutch disk lining. Even though it is significantly important to estimate the temperature of a dry double clutch (DDC) in real-time, few meaningful study of the thermal model of DDC has been known yet. This study presented a thermal analytical model of lumped parameters for a DDC by analyzing its each component firstly. Then a series of experimental test was carried out on the test bench with a patented temperature telemetry system to validate the proposed thermal model. The thermal model, whose optimal parameter values were found by optimization algorithm, was also simulated on the experimental test conditions. The simulation results of DDC temperature show consistency with the experiment, which validates the proposed thermal model of DDC.