Influence of Pulley Actuation Force on the Transient Dynamics of a Metal V-belt CVT

A Continuously variable transmission (CVT) enables a continuous band of gear ratios between the driver and driven shaft. As compared to conventional automatic transmissions with a fixed number of speed ratios, CVTs offer the advantages of better acceleration performance and higher fuel economy. In this paper, the torque transmitting mechanism of a metal pushing V-belt CVT is examined. A detailed continuous one-dimensional transient-dynamic model which captures the CVT behavior during transient shift ratio condition and constant driven pulley sheave actuation force is presented. Inertial dynamics of the belt during transient state and the slip between the metal belt and pulley sheave is accounted for. The driver and driven sides of the CVT system were subject to constant input torque and constant load torque respectively. The results discuss the influence of driven side pulley actuation force on the on the dynamic performance of metal V-belt CVT. CVT response during constant high driven pulley sheave actuation force and low driven pulley sheave actuation force axial force is compared. The results also seem to suggest that with respect to the initial operating condition of CVT, there exists a union of disjoint regimes of the input torque, load torque and driven pulley actuation force parameter values that result in successful torque transmission.