Considering the cost savings involved in building transmissions with only three moving parts, you’ll understand why car companies have become very interested in CVTs lately.
All this may audio complicated, nonetheless it isn’t. In theory, a CVT is much less complex than a normal automated transmission. A planetary gear automatic transmission – marketed in the tens of millions last year – has a huge selection of finely machined shifting parts. It provides wearable friction bands and elaborate digital and hydraulic handles. A CVT like the one explained above has three simple shifting parts: the belt and both pulleys.
There’s another advantage: The cheapest and maximum ratios are also further apart than they would be in a typical step-gear transmission, giving the transmission a larger “ratio spread” This means it is even more Variable Speed Transmission flexible.
The engine can always run at the optimum speed for power or for fuel economy, whatever the wheel speed, this means no revving up or down with each gear change, and the ideal rpm for the right speed all the time.
As a result, instead of five or six ratios, you get an infinite number of ratios between your lowest (smallest-diameter pulley environment) and highest (largest-diameter pulley setting).
Here’s 
an example: When you start from an end, the control computer de-clamps the insight pulley therefore the belt turns the smallest diameter while the result pulley (which goes to the tires) clamps tighter to make the belt switch its largest diameter. This produces the lowest gear ratio (say, 3.0-to-1) for the quickest acceleration. As speed builds, the computer varies the pulley diameters, as conditions dictate, to get the best balance of fuel economic climate and power.