Dry CVT(Continuously variable transmission) consists of a driving pulley and a driven pulley joined by rubber V-belt. Each pulley consists of a fixed flange and a movable flange. The movable flange of the driving pulley has the centrifugal roller and a ramp plate in the flange. The movable flange moves toward a fixed flange under the actuation of a centrifugal roller, as the driving pulley speed increases. The main advantages of the Dry CVT with V-belt, which has been popular in Asia, are a simple mechanism, less maintenance and low cost. The important claim which have an influence on the performance of the Dry CVT is the wear of the centrifugal roller. In this study proposed an improved design of driving pulley reducing the wear of the centrifugal roller in order to provide some design guidelines.

Dry CVT(Continuously variable transmission) consists of a driving pulley and a driven pulley joined by rubber V-belt. Each pulley consists of a fixed flange and a movable flange. The movable flange of the driving pulley has centrifugal rollers and a ramp plate in it. The movable flange moves toward a fixed flange under the actuation of a centrifugal roller, as the driving pulley speed increases. In this study, computer simulation for a driving pulley was carried out for the purpose of analysis a Dry CVT. Based on the simulation we investigated relations between each omponent of driving pulley that consists of roller, movable flange and ramp plate

The scooter CVT is consisted of driving pulley, rubber V-belt and driven pulley. A driving pulley of CVT plays a vital role. In this study, contact forces of movable flange, roller and ramp plate are analyzed for wear of roller. As the results, 1) when incline angle of ramp plate become decreased, reaction difference of ramp plate and movable flange become increased, so roller wear can be decreased, 2) when radius of movable flange profile is increased, reaction difference become increased also. Roller wear had been caused serious claim. Based on the analysis, advanced model of driving pulley is presented.