Second, the earth gear bearings have to play an active function in torque transfer. Planetary systems split the torque input from the sun gear amongst the planet gears, which transfer torque to a world carrier connected to the gearbox output. The bearings that support the planets on the carrier have to bear the entire brunt of this torque transfer.

Or, in acute cases, they may select angular get in touch with or tapered roller bearings, both of which are made to withstand axial loads.
In planetary gearboxes, however, it’s much more difficult to design around these axial forces for just two Helical Gearbox 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 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 excess axial forces amount to little more than an inconvenience. Gearbox designers will often upsize the bearings to support the additional forces.

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

Helical Gears Place Greater Demand on Bearings