Rotate Vector (RV) Reducer

A precision two-stage reducer combining planetary gears with a cycloidal drive, stiff and high-capacity.

An RV reducer is a two-stage precision reducer: the first stage is a planetary gear set, and the second is a cycloidal drive (a cycloidal disc rolling eccentrically inside a ring of pins, producing a large reduction ratio). It was brought to the industrial robot market by Japan's Nabtesco. Compared with a harmonic drive, an RV reducer is larger and heavier, but stiffer, more shock-resistant, and able to carry heavier loads, so traditional six-axis industrial robots typically use RV reducers in heavily loaded joints like the waist, shoulder, and elbow, while using harmonic drives in the lighter forearm and wrist. Humanoid robots prioritize low weight and use RV reducers less often; understanding it is mainly useful for making sense of the industrial-robot and reducer supply chain.

ExampleThe rotating base axis of an industrial robot commonly uses an RV reducer to bear the weight and tipping moment of the entire arm.

Also called

RV Gearbox

Related

Speed Reducer / Gearbox · Cycloidal Reducer · Strain Wave Gear (Harmonic Drive) · Planetary Gearbox · Nabtesco · Industrial Robot

Sources

Cycloidal drive - Wikipedia
Nabtesco Precision Reduction Gears