ABSTRACT
The function of any form of transmission is to match a power source, also called a prime mover, to a driven device. Transmissions serve several purposes, but the major purposes are to allow physical separation between the motor and the driven device, to scale torque, and to scale speed. Obviously, the transmission torque and speed cannot be scaled independently. Transmissions may also be characterized in terms of the steps of speed ratio between the motor and the driven device. The speed ratio for drives using sheaves or gears is usually fixed by geometry and will consist of one or more fixed ratios. In some applications, it is important that the speed ratio can be varied continuously over some desired range during operation. This can be achieved by a stepless transmission.
