Second, the earth gear bearings need to play an active function in 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 output. The bearings that support the planets on the carrier need to bear the entire brunt of this torque transfer.
Or, in acute cases, they could select angular get in touch with or tapered roller bearings, both which are created to withstand axial loads.
In planetary gearboxes, however, it’s a lot more difficult to design around these axial Helical Gearbox forces for just two related reasons. First, there is typically hardly any space in a planetary gearbox to include the type of bulky bearings that may 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 excess 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 enjoy just a supporting function in the functioning of the gearbox. The bearings simply need to support the rotating gear shafts, but they do not play an active part in torque transfer.
Helical Gears Place Better Demand on Bearings