A cycloidal reducer is a type of gear reducer. The basic operation is that an input shaft connects to and drives an eccentric bearing. This bearing further drives a cycloidal disk (sometimes called a cam) that connects to an output shaft.
The cycloidal cam has lobes or teeth that engage with a cam follower, typically with pin or needle bearings. The eccentric rotation of the cam is transformed into rotation of an output shaft at a reduced speed and an increase in torque.
The main advantage of cycloidal reducers is their property of zero or near-zero backlash — for high precision and high accuracy. This is especially in demand where highly precise and accurate positioning is required, for instance in robotic applications, machine tools, and similar applications.
Cycloidal reducers also feature rolling as opposed to sliding contact, thus experiencing less overall wear.