Development of a Novel Dual-Belt Van Doorne's Continuously Variable Transmission for Automobiles — A Preliminary Study

The continuously variable transmission (CVT) is one of the prevailing automotive transmissions. Nowadays, the most popular design is Van Doorne's CVT with single metal pushing V-belt. However, it is only applicable to low-power passenger cars because of its low torque capacity. To overcome this limitation of traditional single-belt Van Doorne's CVT, this research proposes a novel parallel Van Doorne's dual-belt CVT system which can be applied to heavy-duty vehicles. As the first attempt, an analytical model for both torque capacity and power efficiency based on effective radii instead of traditional working radii for the single-belt CVT is developed for this novel CVT system, and this newly developed model is experimentally validated. Evaluation result reveals that the new analytical model based on effective radii is more accurate than that based on working radii. Experimental and simulation results show that the proposed dual-belt CVT system can greatly improve the torque capacity as compared with the single-belt CVT. Moreover, the newly proposed analytical model can provide a foundation for further study of multi-belt CVTs.