• 제목/요약/키워드: 볼베어링 수명

검색결과 27건 처리시간 0.021초

승용차 자동변속기용 트랜스퍼 드라이브 기어 베어링의 효율개선 방법에 관한 연구 (Efficiency Improvement of Transfer Drive Gear Bearings for an Automotive Automatic Transmission)

  • 이인욱;한성길;곽범섭;이호성;송철기
    • 한국기계가공학회지
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    • 제20권3호
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    • pp.40-46
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    • 2021
  • An automatic transmission of automobiles enables comfortable driving experience with lower transmission shifting jerks. However, the assembly structure is more complicated and requires additional components with lower efficiency than the manual transmission system. Extensive research has been conducted to improve the overall transmission efficiency by optimizing each component of the automatic transmission assembly. This study focuses on enhancing the friction torque of double angular contact ball bearings used in automatic transmission. The friction torque of the bearing varies with the operating conditions such as the operational load and rotating speed. Since reducing the friction torque of the bearing tends to deteriorate the durability of the bearing, it is necessary to design the bearing having a minimum required friction torque by determining the durability life of an automatic transmission assembly, In this study, the theoretical life and friction torque of conventional and newly-developed bearings are calculated. The difference in the friction torque between the new and existing bearings are also evaluated.

자동차 변속기용 깊은 홈 볼 베어링의 내구수명 향상 (Improving the Endurance Life of Deep Groove Ball Bearings for Automotive Transmission)

  • 백혜연;편정민;이대용;박태조
    • Tribology and Lubricants
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    • 제31권6호
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    • pp.281-286
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    • 2015
  • Automotive transmission systems are assembled with a large number of gears and shafts, and rolling bearings are used to ensure their smooth operation. Gear oil in the gear box contains solid particles such as wear debris from contacting gears and metallic chips. This particle-enriched lubricating oil can cause premature failure of the rolling bearings. Research aimed at improving the service life of these rolling bearings has been confined mainly to design and lubrication of the inner/outer rings and the rolling elements. In this paper, we redesigned the shape of the cage pocket of a deep groove ball bearing to reduce the premature failure due to particle contamination. Test bearings are assembled with this new cage design containing a hole punched in the cage pocket. Endurance tests are carried out using the contaminated lubricating oil with miracle grid as hard particle. The duration and damaged bearing component shapes are compared for two different cages. The B10 life of bearing with new cage is increased by about 66% compared to the conventional cage. This is because the hard particles can be easily discharged through the pocket hole without staying for a long time in the lubrication regions. This greatly decreases abrasive wear and dents on the highly stressed ball bearing surfaces. Therefore, the cage design of this study, containing a pocket hole, can significantly delay the premature failure of rolling bearings and improve the endurance life.

밀봉형 볼베어링용 그리이스의 노화와 잔류수명 (Deterioration and Residual Life of Grease for Sealed Ball Bearing)

  • 최인혁;김정길;김지현;손성구
    • Tribology and Lubricants
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    • 제18권4호
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    • pp.273-278
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    • 2002
  • Grease deterioration of mineral oil type grease was investigated using sealed deep groove ball bearings (6203) and bearing life test rig. The bearing test was performed under 3,000 rpm and 245 N radial load at 120。C. Grease taken ken tested bearings was checked in using certain evaluation methods, for example, oxidation induction time (OIT), FT-IR peak intensity, leakage .ate, bleeding .ate, total acid number. (TAN) and bearing noise increase. Within these test conditions, OIT, TAN, bleeding rate were changed gradually in accordance with bearing operating time and showed useful indices for deterioration of grease.

박판 궤도륜 볼베어링의 특성해석 및 피로수명 평가 (Analysis and Fatigue Life Evaluation of the Ball Bearing with Thin-Section Raceways)

  • 김완두
    • Tribology and Lubricants
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    • 제13권3호
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    • pp.48-55
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    • 1997
  • The ball bearing with thin-section raceways which is much lighter than other conventional bearings used in most modem passenger cars and small tracks. The important design parameters of this bearing is the groove radius of raceways, the diametral clearance, the free contact angle and so on. The optimal value of these parameters were determined by considering the dynamic load capacity, the contact angle and the calculated fatigue life. The contact angle between a ball and raceways was calculated by considering the local contact deformation and the structural deformation of thin-section raceways which was estimated by FEM. The raceways were made by means of the press-forming process. The fatigue life tester was designed and manufactured. The fatigue life test was executed and the reliability of this bearing was confirmed.

TiN 박막 처리될 베어링 볼의 마모 수명 및 메커니즘에 관한 연구 (A Study on Wear Life and Mechanisms of TiN Coated Bearing Balls against Steel Disks)

  • 한지훈;조정우;이영제
    • 한국윤활학회:학술대회논문집
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    • 한국윤활학회 2000년도 제32회 추계학술대회 정기총회
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    • pp.378-384
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    • 2000
  • This paper presents the results of the repeated sliding tests to determine the wear-life of TiN coated AISI 52100 bearing balls deposited by PVD method and to show the wear mechanisms of those. The sliding tests were carried out using a ball-on-disk tribometer under ambient conditions. The coefficient of friction, wear volume and the cycles to failures of TiN coated bearing balls were measured with different normal loads and roughness of lower specimens. On the wear-life diagram, the normal loads and the cycles to failure showed the good linear relation on log-log coordinate. With a decreasing normal load, the diagram showed that the wear-limits, at which the coated bearing balls survived more than 4000cycles were under 0.1N of the normal load.

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응력 기반 볼 베어링의 접촉피로수명 예측 (Stress based Fatigue Life Prediction for Ball Bearing)

  • 김태완;이상돈;조용주
    • 한국윤활학회:학술대회논문집
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    • 한국윤활학회 2004년도 학술대회지
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    • pp.339-349
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    • 2004
  • The method for fatigue life prediction of ball bearing is proposed applying the algorithm of contact fatigue prediction based on stress analysis. In order to do this, a series of simulation such as initial surface stress analysis, EHL analysis, subsurface stress analysis and fatigue analysis are conducted from the loading at each ball location calculated for a bearing subjected to external bearing load and contact shape function. And uniaxial fatigue tests are performed to obtain fatigue parameter of AISI 52100 steel. It was found that since stress is usually higher at the inner raceway contact than at the outer raceway contact, fatigue failure occurs on the inner raceway first. When the fatigue life calculated in the stress-based method are compared with $L_{50}$ life of L-P model, Crossland criterion for the radial load increment is similar to $L_{50}$ life and Dang Van criterion for the axial load increment is similar. In the case of EHL contact. there is no difference of fatigue life between dry contact and EHL contact, when maximum Hertz pressure exceeds 2.5GPa.

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군용차량 클러치 내구수명 향상에 대한 연구 (Design Technique for Durability Improvement of Military Vehicle Clutch System)

  • 신철호;강태우;김성곤;김선진
    • 한국산학기술학회논문지
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    • 제20권10호
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    • pp.117-124
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    • 2019
  • 국군이 운용중인 대부분의 군 전용차량은 개발이 완료된지 15년이 넘었으며, 개발 당시의 기술력과 정비성을 고려하여 수동변속기를 채택하고 있다. 수동변속기는 엔진과 변속기 사이에 동력을 조절/차단하는 클러치를 포함한다. 본 연구의 대상이 되는 2.5톤 군용차량은 수동변속기와 클러치 시스템을 적용하고, 클러치 커버와 릴리스 베어링 간극을 수동으로 조절해야 했다. 이러한 특성으로 인하여 클러치 디스크 조기마모, 클러치 커버 파손 등의 품질문제가 발생하였다. 본 연구는 발생된 품질문제를 해결하기 위하여, 클러치 커버와 릴리스 베어링의 간극을 자동으로 설정하도록 하고 클러치 디스크 자체의 성능도 향상시키는 과정을 거쳤다. 개선된 시스템을 평가하기 위해서, 단시간에 기어변속을 하는 가속내구시험을 수행하였으며 추가적으로 군인이 직접 운전을 하여 차량에 적용하였을 때 이상이 없음을 증명하였다. 본 연구활동을 통해, 클러치 간극을 조정할 필요가 없도록 하여 차량 정비 인력의 정비시간을 단축하였다. 또한, 클러치 간극을 조정해 주지 못함으로써 발생되는 품질문제를 해소하여, 근본적인 개선책을 제시하였다고 볼 수 있다.