A belt drive is the drive to which the belt is fastened as a means of load transfer. The belt drive is used to start two engines or generators by the internal combustion engine. The first device that was used in such a way was the alternator. This generator supplies electricity for the lighting of the vehicle. It is driven by the V-belt, so no additional power is required.

Depending on the vehicle model V-belt also controls other devices. The water pump, which is required for cooling, is supplied with energy in this way. In addition, the air conditioning compressor can also be powered by the belt drive. Its great advantage is that the energy transfer is carried out simply and efficiently. This is the reason the system is used almost in all cars. In cars primarily are used timing belts, V- and poly-V belts.