With the many industrial servo motor gear reducers gearboxes available today, it’s important to match the proper kind of gearbox with the drive, motor, and load. When a machine needs a servosystem (drive and electric motor), the gearbox type is crucial for accurate and repeatable movement. Planetary gearboxes fit the bill for servo applications.
High-precision helical planetary gearboxes are an excellent choice for applications that need accuracy and reliability. Planetary gearboxes have very low backlash ratings (typically ranging from one to nine arc-min), and when sized correctly provide a service existence of over 20,000 hours with practically no maintenance. Helical planetary gears provide very noiseless and better 
operation as compared to competitive products.
Precision gearboxes are carefully machined to high tolerances – think clockmaker, not blacksmith. They offer power densities that translates to small bundle size and efficiencies of 90% and greater.
Servomotors often drive loads directly with no need for a gearbox, however in many applications it’s advantageous to use a gearbox between the motor and load.
One main cause to employ a gearbox is torque multiplication. It lets designers make use of smaller sized servosystems that consumes less energy. Instead of buying relatively huge servodrives and motors, developer can use smaller elements, saving space and money.
Output torque improves in direct proportion to the apparatus ratio, and top rate of the output shaft decreases. If a credit card applicatoin can withstand the reduced speed, a relatively small servosystem can supply high torque.
Gearboxes may also address inertia mismatches. For powerful servosystems — those with high powerful responses or low overshoot, for example – the ratio between your reflected load inertia and motor inertia should be only practical, preferably under ten-to-one. A precision gearbox decreases the reflected inertia by the square of the decrease ratio. For instance, utilizing a 25:1 gearbox decreases the load’s reflected inertia by one factor of 625, a significant improvement.