Rotary bearings are mechanical components that bear a load — such as an electric motor’s output shaft — while minimizing friction to allow for the free turning of that axis in one (most common) or two planes. In most cases, they’re the support interface between rotating and stationary portions of the assembly. Loads borne by rotary bearings are either:
Radial — loads applied perpendicular to the bearing’s rotational axis
Axial — loads applied parallel to the bearing’s rotational axis
As we'll explore, components classified as radial bearings support the first load type; components classified as thrust bearings support the second load type. Many rotary-bearing designs (called combination bearings) simultaneously resolve both load types. Still others even allow concurrent linear and rotary motion.
In this Design Guide, we detail rotary bearings that take the form of plain (sleeve) style bearings as well as rolling-element rotary bearings for the support of radial as well as axial loads.