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The Influence of Spin and Lifetime in Design of Traction Drive Continuously Variable Transmissions
Technical Paper
2001-01-3841
ISSN: 0148-7191, e-ISSN: 2688-3627
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English
Abstract
Fundamental issues on the TD-CVT (Traction Drive Continuously Variable Transmission) are efficiency, lifetime and variable speed ratio control. One reason of decreasing efficiency on the TD-CVT is the spin motion. Spin causes power loss, reduces available traction forces, and generates traction forces perpendicular to the rolling direction. Thus, spin has an ill effect on traction drives and should be kept as small as possible to have best performance. For optimal performance, it is necessary to find a traction drive configuration that results in a minimum amount of spin. TD-CVTs operate in the high contact-stress. The achievement of a given number of stress repetitions without failures can only be assigned a probability. Most drives are rated against the 90% probability of surviving the number of stress repetitions associated with the rated number of hours of operation at the rated speed and load. A contact fatigue life analysis for TD-CVTs based on modified Lundberg-Palmgren fatigue theory is used to predict lifetime for a compact ball variator TD-CVT for bicycle. The effects of power, size and transmission ratio on TD-CVT lifetime are shown.
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Citation
Forti, A. and Dedini, F., "The Influence of Spin and Lifetime in Design of Traction Drive Continuously Variable Transmissions," SAE Technical Paper 2001-01-3841, 2001, https://doi.org/10.4271/2001-01-3841.Also In
References
- Heilich, F. W. Shube, E. E. Traction Drives - Selection and Application Pleassey Dynamics Corporation Hillside, New Jersey 1983
- Lim, K.H. Ullman, D.G. Optimal Design of Traction Drive Continuously Variable Transmissions Journal of Mechanisms, Transmissions and Automation in Design 111 264 269 June 1989
- Forti, A. W. Design and optimization of a CVT for bicycles UNICAMP Campinas, SP, Brazil 1997
- Seabury, J.J. Adams, W.C. Ramey, M.R. Influence of Pedalling Rate and Power Output on Energy Expenditure During Bicycle Ergometry Ergonomics 50 5 491 498 1977
- Forti, A. W. Dedini F. G. Development of Bicycle-suitable transmissions through performance simulation and ergometric factors VI International Mobility Technology Conference and Exhibit São Paulo, Brazil October 27-29 1997 SAE Paper 973082
- Soden, P.D. Adeyefa, B.A. Forces Applied to a Bicycle During Normal Cycling Journal of Biomechanics 12 527 541 1979
- Coy, J. J. Loewenthal, S. H. Zaretsky, E. V. Fatigue Life Analysis for Traction Drives With Application to a Toroidal Type Geometry Nasa Technical Note D-8362 December 1976
- ROHN, D. A. LOEWENTHAL, S. H. COY, J. J. Simplified Fatigue Life Analysis for Traction Drive Contacts Journal of Mechanical Design 103 430 439 April 1981
- TEVAARWERK, J. L. Johnson, K. L. The influence of Fluid Rheology on the performance of Traction Drives Journal of Lubrication Technology 101 266 274 July 1979