A new standard of epicyclic efficiency – a practical comparison of planetary and orbitless gear-heads

Ein neuer Standard der Planeteneffizienz – Ein praxisnaher Vergleich von Planeten,- und Orbitlosen Getrieben


An Orbitlesspat.pend. gear-head is a novel fixed-ratio Epicyclic gear-head with crank-shaft planet pinions and two carriers but no ring gear. It provides half the reduction ratio of a Planetary gear-head with similar pinions and shares many characteristics such as torque splitting and co-axial drive shafts that spin in a common direction. Three prototype Orbitless gear-heads are constructed, each with a different planet support mechanism. It is shown that load capacity is marginally improved by using ball instead of plain bearings, and greatly improved by mounting the bearings to the planets rather than the carriers. In comparison to an off-the-shelf Planetary gear-head, friction losses are reduced by up to 59% and total input power is reduced by up to 33% over the operating range of the motor and gear-head.

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Correspondence to L. J. Stocco.

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Stocco, L.J., Gloeckner, R. A new standard of epicyclic efficiency – a practical comparison of planetary and orbitless gear-heads. Forsch Ingenieurwes 81, 153–161 (2017). https://doi.org/10.1007/s10010-017-0235-z

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