Abstract
We present an experimental investigation of the pushing V-belt CVT dynamics with the aim of comparing the experimental data with the theoretical predictions of the Carbone, Mangialardi, Mantriota (CMM) model (1). A very good agreement between theory and experiments is found. In particular it is shown that, during creep-mode (slow) shifting, the rate of change of the speed of ratio depends linearly on the logarithm of the ratio between the axial clamping forces acting on the two movable pulleys. The shifting speed is also shown to be proportional to the angular velocity of the primary pulley. The results of this study are of utmost importance for the design of advanced CVT control systems and the improvement of the CVT efficiency, cars´ drivability and fuel economy.
Keywords: Continuously Variable Transmissions, Automatic Transmission, V-belt, Pushing-Belt, Metal-Chain, Shifting Dynamics.