International Journal of Precision Engineering and Manufacturing

Korean Society for Precision Engineering (한국정밀공학회)
권호 표지

An Inner-spherical Continuously Variable Transmission for Electric Bicycles

  • Park, Moon-Woo (Department of Mechanical Design Engineering, Graduate School, Pusan National University) ;
  • Lee, Hyoung-Woo (School of Mechanical Engineering, Pusan National University) ;
  • Park, No-Gill (School of Mechanical Engineering, Pusan National University)
  • Published : 2008.01.01
Download PDF
⟨ Previous Next ⟩

Abstract

A new continuously variable transmission (CVT) for electric bicycles was developed using a traction drive mechanism with inner and outer spherical rotors. This electric bicycle CVT permits three propulsion modes: human-power only, motor-power only, or a combination of motor power and human power. In addition, the electric bicycle CVT has high power efficiency, large torque capacity, improved drivability, and good packageability. A prototype was manufactured based on a conceptual design, a performance analysis, and a detailed design. This prototype has a rated power of 250 W and input motor speed of 20 rad/s for an overall speed ratio in the range 0.3-1.2. A bench test was conducted to measure the power transmission performance of the prototype.

Keywords

References

  1. Lomonova, E. A., Vandenput, A. J. A., Rubacek, J., d'Herripon, B. and Roovers, G., 'Development of an Improved Electrically Assisted Bicycle,' Industry Applications Conference, Vol. 1, pp. 384-389, 2002
  2. Andreassi, L., Cordiner, S. and Romanelli, F., 'Conceptual Design and Modeling of a Fuel Cell Pedal Assisted Bicycle,' SAE, Technical Paper No. 2004-32-0049, 2004
  3. Seong, S. H., Ryu, J. H. and Park, N. G., 'Conceptual Design of Inner-Spherical Continuously Variable Transmission for Bicycle Usage,' International Journal of Automotive Technology, Vol. 6, No. 5, pp. 467-473, 2005
  4. Ryu, J. H., Kim, J. H. and Park, N. G., 'Development of the Inner Spherical Traction CVT for Scooters,' Fall Conf. Proc. of KSAE, pp. 577−581, 2004
  5. Ku, I. K. and Park, N. G., 'An Introduction of a New Traction Drive Pairing with the Inner and the Outer Surface of the Spherical Rotors for Automobile Usage,' International Continuously Variable and Hybrid Transmission Congress, 2004
  6. Park, M. W., Lee, H. W., Park, N. G. and Sang H. S., 'Development of Inner-Spherical Continuously Variable Transmission for Bicycles,' International Journal of Automotive Technology, Vol.8, No.5, pp. 593-598. 2007
  7. Heilich, F. W. and Shube, E. E., 'Traction Drives: Selection and Application,' Marcel Dekker, pp. 234-320, 1983
  8. Pillkey, W. D., 'Formulas for Stress, Strain and Structural Matrices,' John Wiley, pp. 514-550, 1994
  9. Rohn, D. A., Loewenthal, S. H. and Coy, J. J., 'Simplified Fatigue Life Analysis for Traction Drive Contacts,' ASME Journal of Mechanical Design, Vol. 103, No. 1, pp. 430-439, 1981 https://doi.org/10.1115/1.3254931
  10. Harvey, P. D., 'Engineering Properties of Steel,' American Society for Metals 2nd edn. Metals Park, pp. 134-150, 1999