A cycloidal reducer is a kind of gear reducer. The essential operation is that an insight shaft connects to and drives an eccentric bearing. This bearing additional drives a cycloidal disk (sometimes referred to as a cam) that connects to an output shaft.

cycloidal reducer
Typical cycloidal speed reducers, such as these Dojen series reducers from Onvio, offer zero backlash by combining a substance reduction cam with preloaded, complete compliment needle bearing cam followers.

The cycloidal disk (or cam) has lobes or teeth that engage with some form of cam follower, typically a pin or needle bearings. The eccentric rotation of the cam is transformed into rotation of an result shaft at a reduced speed and an increase in torque.

The main advantage of cycloidal reducers is their house of zero or near-zero backlash, which translates into high precision and high accuracy. That is especially popular where highly precise and accurate positioning is Oil-free Air Compressor required, for example in robotic applications, machine tools, and comparable applications. Cycloidal reducers also feature rolling as opposed to sliding contact, therefore experiencing less overall use.