ABSTRACT
The friction drive is one of the most widespread types of power transmission. For example, all wheeled vehicles, including bicycles, motorcycles, cars, trucks, and railroad locomotives, are representative of this type of drive, where one wheel has a very large diameter (in- nitely large at at portions of the road). In machinery, however, friction drives, because of low load-carrying capacity, are used mainly for stepless speed variators (see Chapter 11) and in cases where slippage in the drive is required to prevent overload of the mechanism.
