A Continuously Variable Transmission Controlled by an Electric Motor

A new continuously variable transmission has been developed. The new transmission could convert step transmissions to continuously variable transmissions with an electric motor and two planetary gear sets connected with a worm gear. The output speed of the transmission is determined by the speed of the electric motor instead of the input speed. On the other hand, the output torque comes from the input torque and does not depend on the torque of the electric motor. The output speed could be easily changed by controlling the speed of the electric motor of a small power. The overall structure of the transmission with a step transmission is simple and efficient since a torque converter is not needed for the transmission.