In planetary gearbox assemblies, how are wave springs utilized to maintain bearing preload and prevent axial backlash?

Planetary gearboxes experience high radial and axial thrust loads under dynamic speed changes, leading to gear backlash and bearing wear.

Application of Wave Springs:
1. Constant Axial Preload: A Crest-to-Crest wave spring is installed behind the outer race of the taper roller bearing or deep groove ball bearing. It provides a constant, highly predictable axial force that offsets cumulative component manufacturing tolerances.
2. Backlash Elimination: By taking up the axial clearance ('play'), the wave spring keeps the gear assemblies locked tightly in-mesh, reducing noise, vibration, and harshness (NVH).
3. Shock Absorption: In high-speed reversing gearboxes, the spring acts as an axial shock absorber, damping high-frequency vibrations and shock loads that would otherwise fracture gear teeth.