What is the reason for the "strange noise" emitted by the planetary gearbox? How can it be solved?
The selection of planetary gearbox should comprehensively consider economy, accuracy, noise, and temperature rise, and choose according to the actual situation. This article shares knowledge on selecting planetary gearboxes and how to avoid making "strange noises" from planetary gearboxes

The operating principle of planetary gearbox

As a common transmission mechanism, planetary gearbox has the characteristics of small size, good sealing, high transmission accuracy, large transmission torque, and easy installation. The planetary gear reducer is internally meshed with a sun gear and a planetary gear. The sun gear drives the planetary gear, which in turn rotates the planetary carrier and output shaft, thereby achieving deceleration and torque amplification.

Sun gear rotation and planetary gear revolution: When the sun gear rotates under external power, it meshes with the planetary gears, forcing them to rotate on their own. At the same time, due to the meshing of the other side of the planetary gear with the ring gear, the ring gear is fixed, forcing the planetary gear to revolve around the sun gear along the trajectory of the ring gear while self propagating.

What is the reason for this phenomenon?
Resonance has occurred between the gearbox and the installation mechanism! Under what circumstances is resonance prone to occur?
Firstly, during the gear transmission process of the gearbox, there will definitely be vibration because its own weight density is relatively heavy, with small amplitude and frequency, making it difficult to detect.

But the following reasons can cause the resonance frequency to increase, leading to abnormal noise:

1. The installation center of gravity of the reducer is too high, and the structural rigidity of the installation platform is insufficient. The overall equipment density is light, which is prone to resonance.
2. The installation error of the output shaft is too large. For example, in screw drive structures, vertical loads are often used, and there is a certain inclination angle between the load and the screw. The more severe the inclination, the louder the noise.
3. If the load inertia does not match the motor inertia and exceeds the adjustment range of the motor, it is necessary to increase the speed ratio of the reducer or further reduce the speed to control resonance.
In general, the selection of planetary gearboxes should be based on balancing economy, accuracy, noise, and temperature rise, as well as considering the installation method and motor compatibility. Choose according to the actual situation.