With the many industrial gearboxes available today, it’s vital that you match the proper type of gearbox with the drive, motor, and load. Whenever a machine requires a servosystem (drive and engine), 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 precision and reliability. Planetary gearboxes have very low backlash rankings (typically ranging from someone to nine arc-min), and when sized correctly offer a service lifestyle of over 20,000 hours with virtually no maintenance. Helical planetary gears also provide very calm 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 means small package size and efficiencies of 90% and greater.
Servomotors often drive loads directly with no need for a gearbox, however in many applications it’s servo motor gear reducers beneficial to use a gearbox between the motor and load.
One main reason to use a gearbox is torque multiplication. It lets designers use smaller sized servosystems that consumes less energy. Instead of buying relatively large servodrives and motors, developer can use smaller components, saving space and cash.
Output torque improves in direct proportion to the apparatus ratio, and top acceleration of the output shaft decreases. If an application can withstand the reduced speed, a relatively small servosystem can supply 
high torque.
Gearboxes can also address inertia mismatches. For high performance servosystems — those with high powerful responses or low overshoot, for instance – the ratio between the reflected load inertia and engine inertia should be only practical, ideally under ten-to-one. A precision gearbox decreases the reflected inertia by the square of the decrease ratio. For instance, using a 25:1 gearbox reduces the load’s reflected inertia by a factor of 625, a significant improvement.