Bushing/Bearing

A bushing (also called plain bearing or sleeve bearing) and bearing are mechanical components designed to constrain relative motion to only the desired motion and reduce friction between moving parts. In hinge assemblies, they specifically facilitate rotational movement between connected parts while minimizing wear, vibration, and energy loss. Bushings typically provide sliding contact surfaces, while bearings (such as ball or roller bearings) use rolling elements for even lower friction.

Bushings operate on the principle of sliding friction, where a lubricated surface allows one part to slide against another with minimal resistance. Bearings use rolling elements (balls, rollers) that rotate between inner and outer races, converting sliding friction into rolling friction which significantly reduces torque requirements and wear. Both create precise clearances that maintain alignment while accommodating thermal expansion and load variations.