Mechanical Continuously Variable Transmissions
In contrast to the mechanical stepped transmissions so far used in motor vehicles, mechanical continuously variable transmissions, also called CVTs, have certain advantages based on their principle. The power characteristic is shown in Fig. 3-70. As a result of the continuously variable torque conversion the presented power curve (center) represents the converter characteristic curve. In order to produce a delivery map (right) which adjusts to the different driving conditions, the CVT only requires a demand characteristic line (left) from the engine. Except for the starting area, which requires an additional clutch, the (for a sufficient range of transmission ratios) the entire demand map can be covered in this way.