Second, the planet gear bearings need to play an active part in Helical Gearbox torque transfer. Planetary systems split the torque input from the sun gear amongst the planet gears, which in turn transfer torque to a planet carrier connected to the gearbox result. The bearings that support the planets on the carrier need to bear the full brunt of that torque transfer.

Or, in acute cases, they may select angular contact or tapered roller bearings, both which are created to withstand axial loads.
In planetary gearboxes, however, it’s much more difficult to design around these axial forces for two related reasons. Initial, there is typically very little area in a planetary gearbox to include the kind of bulky bearings that can tolerate high axial forces.

The presence of axial forces makes things very different for the bearings that support helical gears. But it is important to make a distinction between fixed-axis and planetary gearboxes. In fixed-axis gearboxes, the additional axial forces total little more than a hassle. Gearbox designers will most likely upsize the bearings to support the additional forces.

Since they won’t need to withstand any axial forces, spur gear bearings play just a supporting part in the functioning of the gearbox. The bearings simply need to support the rotating equipment shafts, however they do not really play an active function in torque transfer.

Helical Gears Place Greater Demand on Bearings