Transactions of the Korean Society of Automotive Engineers (한국자동차공학회논문집)

The Korean Society of Automotive Engineers (한국자동차공학회)
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Analysis on the Shift Characteristics of Semi-Spherical CVT using 2-dimensional Friction Model

2차원 마찰모델을 이용한 구면무단변속기의 변속특성해석

  • Kong, Jin-Hyung (Technical Center, Hyundai-Kia Motors) ;
  • Lim, Won-Sik (Department of Automotive Engineering, Seoul National University of Technology) ;
  • Park, Yeon-Gil (School of Mechanical Design and Automation Engineering, Seoul National University of Technology) ;
  • Kim, Jung-Yun (School of Mechanical and Automotive Engineering, Catholic University of Daegu)
  • 공진형 (현대기아자동차 기술연구소) ;
  • 임원식 (서울산업대학교 자동차공학과) ;
  • 박영일 (서울산업대학교 기계설계자동화공학부) ;
  • 김정윤 (대구가톨릭대학교 기계자동차공학부)
  • Published : 2008.07.01
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Abstract

Semi-spherical CVT(SS-CVT) is one of friction drives, which transmits power via the friction force between a spherical shaped variator and output disks. The variator varies the speed ratio of SS-CVT continuously as well as transmits input power into the output shaft. Therefore two friction forces are normally applied on the variator; one is the longitudinal friction force for power transmission and the other is the lateral for shifting. In order to investigate the dynamic behavior of SS-CVT, we introduced a numerical model of 2-dimensional friction force using a function of slip ratio and slip angle. And a dynamic model, which describes the shifting mechanism of SS-CVT, is developed through 3-dimensional vector analysis. Finally we presented numerical results of the shift characteristics focused on the transient behavior of the variator's slip ratio and slip angle. The numerical results also show the typical CVT shifting characteristics of SS-CVT and stable shifting behaviors of the variator.

Keywords

References

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