Abstract
Authors describe technologies to improve the efficiency of toroidal CVT. Firstly, technologies to improve the efficiency of toroidal variator are discussed. Improvements of Power Roller design and loading force optimization show higher efficiency than conventional toroidal variator. One of the important points in the traction drive system is to use high traction coefficient as much as possible. The influences of new technologies which can make traction coefficient higher are discussed. The toroidal variator efficiency of 97% at the maximum input torque will come true with this research. Secondly authors describe efficiency of power recirculation system which is composed of toroidal variator and planetary gear mechanism. The influence of the efficiency of variator and planetary gear mechanism upon the whole transmission efficiency is discussed. Comparison between belt variator and toroidal variator is also discussed. These variator have different characteristic of efficiency on rotation speed and transmitting torque each other.
