Kinematic Analysis and Modeling of Traction Drive CVT

This paper presents a systematic model for the design and analysis of toroidal traction drive continuously variable transmissions (CVT). The contacts between the input disk, the roller and the output disk of the traction drive are formulated using classical Hertzian contact theory. The traction force and side slip force occurring in CVT operation are modeled based on elasto-hydrodynamic theory and are correlated to the traction drive geometric and kinematic parameters. The model allows for the quantitative analysis of traction drive operation under specified torque inputs and over the desired ratio range.