An epicyclic gear train (also known as a planetary gearset) is a gear reduction assembly consisting of two gears mounted so that the center of one gear (the "planet") revolves … See more

From the above formulae, we can also derive the accelerations of the sun, ring and carrier, which are: See more

A convenient approach to determine the various speed ratios available in a planetary gear train begins by considering the speed ratio of the gear train when the carrier is held fixed. … See more

Around 500 BC, the Greeks invented the idea of epicycles, of circles travelling on the circular orbits. With this theory Claudius Ptolemy in the Almagest in 148 AD was able to … See more

In order that the planet gear teeth mesh properly with both the sun and ring gears, assuming $${\displaystyle n_{\text{p}}}$$ equally spaced … See more

The gear ratio of an epicyclic gearing system is somewhat non-intuitive, particularly because there are several ways in which an … See more

Some epicyclic gear trains employ two planetary gears which mesh with each other. One of these planets meshes with the sun gear, the other planet meshes with the ring gear. This … See more