Design of Shaft Drive CVT: Calculation of Transmitted Torque and Efficiency Available to Purchase

The novel mechanism of CVT (Shaft Drive CVT, S-CVT) was developed by the authors. To improve the efficiency and the torque capacity of the S-CVT, the theoretical efficiency is calculated in this paper. The efficiency is calculated from the component of torque and the component of velocity. The component of torque is calculated from the loss torque of the bearings. The component of velocity is calculated from the shear model of the traction oil in the EHL contact area. To improve the efficiency and the torque capacity, an optimum design of the two disks/rollers was done by using this calculation. In case of conical disk/roller, 9.4 Nm of the torque capacity and 2.5 point of the efficiency were improved by comparison to the present conical disk/roller. In case of concave disk/roller, though 2.1 point of the efficiency decreased, 58.8 Nm of the torque capacity was improved by comparison with the present.