The purpose of a reduction gear is to modify the output speed and/or the torque between the inlet shaft and the outlet shaft of a particular mechanism. Motor shaft in the outlet shaft: epicycloidal train. Motor shaft perdendicular to the outlet shaft: wheel and auger for industrial installations, automobile differential shafts, etc.
For low and medium power output uses (up to a few kilowatts), the standard single phase network suffices. For high power output uses, alternating current motors are generally supplied by a polyphase electrical power source. The most frequently used system is the three-phase system (120° between phases) used by electricity distributors.
A speed regulator is a mechanical device allowing for continual variation of a motor's gear ratio. It is used instead of a gearbox. The angle transmission allows for the power of a mechanism to be transmitted at a 1:1 ratio for an angle.