International Journal of Automotive Technology

The Korean Society of Automotive Engineers (한국자동차공학회)
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DEVELOPMENT OF INNER-SPHERICAL CONTINUOUSLY VARIABLE TRANSMISSION FOR BICYCLES

  • Park, M.W. (Department of Mechanical Design Engineering, Graduate School, Pusan National University) ;
  • Lee, H.W. (School of Mechanical Engineering, Pusan National University) ;
  • Park, N.G. (School of Mechanical Engineering, Pusan National University) ;
  • Sang, H.S. (School of Fire & Disaster Prevention, Kyungil University)
  • Published : 2007.10.01
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Abstract

A new continuously variable transmission for bicycles(B-CVT) is developed by using a traction drive mechanism having inner and outer spherical rotors. The B-CVT has high power efficiency, large torque capacity, improved drivability and good packageability. The ratio change mechanism for the B-CVT is very simple, in contrast with other traction drive CVTs. After completing a conceptual design, a performance analysis and a detail design, a prototype of the B-CVT has been manufactured. The prototype has rated power of 100 watts, pedal speed of 6 rad/s and an overall speed ratio of 1.0-4.0. A bench test and an actual bicycle test have been performed to verify the practicability of the B-CVT.

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References

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