Second, the planet gear bearings have to play an active function in torque transfer. Planetary systems split the torque insight from the sun gear amongst the earth gears, which in turn transfer torque to a planet carrier connected to the gearbox result. The bearings that support the planets on the carrier have to bear the full brunt of this torque transfer.
Or, in extreme cases, they may select angular contact or tapered roller bearings, both which are made to withstand axial loads.
In planetary gearboxes, however, it’s a lot more difficult to create around these axial forces for just two related reasons. First, there is typically very little space in a planetary gearbox to include the type 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 Helical Gearbox between fixed-axis and planetary gearboxes. In fixed-axis gearboxes, the additional axial forces total little more than a hassle. Gearbox designers will often upsize the bearings to accommodate the additional forces.
Since they won’t need to withstand any axial forces, spur gear bearings enjoy just a supporting role in the functioning of the gearbox. The bearings should just support the rotating equipment shafts, however they do not really play an active function in torque transfer.
Helical Gears Place Better Demand on Bearings