Second, the earth gear bearings need to play an active part in torque transfer. Planetary systems split the torque insight from sunlight gear amongst the earth gears, which transfer torque to a world carrier connected to the gearbox result. The bearings that support the planets on the carrier need to bear the entire brunt of that torque transfer.
Or, in extreme cases, they could select angular get in touch with or Helical Gearbox tapered roller bearings, both which are designed to withstand axial loads.
In planetary gearboxes, however, it’s much more difficult to design around these axial forces for two related reasons. 1st, there is typically hardly any area in a planetary gearbox to incorporate the type of bulky bearings that may tolerate high axial forces.
The existence of axial forces makes things very different for the bearings that support helical gears. But it is critical 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 often upsize the bearings to accommodate 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 should just support the rotating equipment shafts, but they do not play an active part in torque transfer.
Helical Gears Place Better Demand on Bearings