With the many commercial gearboxes available today, it’s vital that you match the proper type of gearbox with the drive, motor, and load. When a machine needs a servosystem (drive and motor), the gearbox type is crucial for accurate and repeatable motion. 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 servo motor gear reducers ratings (typically ranging from one to nine arc-min), so when sized correctly provide a service lifestyle of over 20,000 hours with practically no maintenance. Helical planetary gears also provide very peaceful 
and more efficient operation in comparison with competitive products.
Precision gearboxes are carefully machined to high tolerances – think clockmaker, not blacksmith. They provide power densities that translates to small package size and efficiencies of 90% and greater.
Servomotors often drive loads directly without the need for a gearbox, but in many applications it’s beneficial to make use of a gearbox between the motor and load.
One main cause to use a gearbox is torque multiplication. It lets designers use smaller sized servosystems that consumes less energy. Instead of buying relatively huge servodrives and motors, designer can use smaller components, saving space and money.
Output torque raises in direct proportion to the apparatus ratio, and top quickness of the output shaft decreases. If an application can withstand the reduced speed, a relatively little servosystem can supply high torque.
Gearboxes can also address inertia mismatches. For high performance servosystems — those with high powerful responses or low overshoot, for example – the ratio between the reflected load inertia and electric motor inertia should be as low as practical, ideally under ten-to-one. A precision gearbox decreases the reflected inertia by the sq . of the decrease ratio. For instance, utilizing a 25:1 gearbox reduces the load’s reflected inertia by a factor of 625, a substantial improvement.