Perhaps the most obvious is to increase precision, which really is a function of manufacturing and assembly tolerances, gear tooth surface finish, and the center distance of the tooth mesh. Sound can be affected by gear and housing components in addition to lubricants. In general, expect to spend more for quieter, smoother gears.
Don’t make the mistake of over-specifying the electric motor. Remember, the insight pinion on the planetary must be able manage the motor’s result torque. What’s more, if you’re utilizing a multi-stage gearhead, the output stage should be strong enough to absorb the developed torque. Certainly, using a more powerful motor than required will require a larger and more costly gearhead.
Consider current limiting to safely impose limits on gearbox size. With servomotors, output torque can be a linear function of current. Therefore besides safeguarding the gearbox, current limiting also defends the electric motor and drive by clipping peak torque, which can be from 2.5 to 3.5 times continuous torque.

In each planetary stage, five gears are concurrently in mesh. Although it’s impossible to totally eliminate noise from this assembly, there are several ways to reduce it.

As an ancillary benefit, the geometry of planetaries matches the shape of electric motors. Therefore the gearhead can be close in diameter to the servomotor, with the output shaft in-line.
Highly rigid (servo grade) gearheads are generally more costly than lighter duty types. However, for quick acceleration and deceleration, a servo-grade gearhead could be the only sensible choice. In such applications, the gearhead could be viewed as a mechanical springtime. The torsional deflection resulting from the spring action increases backlash, compounding the effects of free shaft movement.
Servo-grade gearheads incorporate several construction features to reduce torsional stress and deflection. Among the more common are large diameter result shafts and beefed up support for satellite-gear shafts. Stiff or “rigid” gearheads have a tendency to be the costliest of planetaries.
The kind of bearings supporting the output shaft depends on the load. High radial or axial loads usually necessitate rolling component bearings. Small planetaries could get by with low-cost sleeve bearings or other economical types with fairly low axial and radial load capacity. For larger and servo-grade gearheads, durable output shaft bearings are often required.
Like the majority of gears, planetaries make noise. And the quicker they operate, the louder they obtain.

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