Development of 3D Dynamic and 1D Numerical Model for Computing Pulley Ratio of Chain CVT Transmission

The pulley ratio of continuously variable transmission (CVT) is one of the most important factors in the quality evaluation for shift smoothness and response. The numerical model with pulley ratio map has been widely used for shift control. It has been obtained with the experimental method but its cost is very expensive. This paper proposes a way to make the pulley ratio map of the chain CVT via virtual simulation to decrease the cost. The 3D dynamic analysis model of it has been developed by using the general purpose dynamic analysis software, DAFUL. The dynamic analysis is carried out to get the pulley ratio map. It has been obtained by varying the ratio of torque, ratio of clamping forces, and changing rate of clamping force. The interpolation function of pulley ratio map is developed using MATLAB Simulink. This method has been verified as compared simulation with experiment result.