The gearbox is a mechanism which transmits and converts torque to one or more mechanical transmissions. The gearbox that converts high angular velocity of the input shaft into a lower angular velocity of the output shaft while increasing the torque, is usually called demultiplier, and the gearbox, which converts a low angular velocity to the higher is usually called the multiplier.

Selection of the type and operating parameters of the gearbox is the most critical task in the development of anelectric drive system. Therefore, the qualification and experience in develoment of similar systems is the basic requirement to ensure process reliability.