epicyclic train

American  

noun

Machinery.

1. a train of gears or pulleys in which one or more of the axes revolve about a central axis.

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epicyclic train British  

noun

1. a cluster of gears consisting of a central gearwheel with external teeth (the sun), a coaxial gearwheel of greater diameter with internal teeth (the annulus), and one or more planetary gears engaging with both of them to provide a large gear ratio in a compact space

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Etymology

Origin of epicyclic train

First recorded in 1885–90

Example Sentences

In both classes, the action involves the use of some sort of epicyclic train, since the motions to be explained are both orbital and axial.

From Scientific American Supplement, No. 447, July 26, 1884 by Various

All the variable speed gears at present made consist of toothed wheel mechanism either at the hub or crank-bracket, and nearly all are based on the same epicyclic train of toothed wheels.

From Encyclopaedia Britannica, 11th Edition, Volume 3, Slice 7 "Bible" to "Bisectrix" by Various