Compound Planetary

By Spencer Connor

Fairly rare but occasionally of use, the compound planetary splits the planet gears into two (one meshing to the sun gear and the other meshing to the ring gear). This gives an additional degree of freedom to either increase or decrease the gear ratio further, or simply to tune it more precisely. Just like a normal planetary, it can be used in three configurations with one rotation fixed for three different gear ratios or be used as an unequal summer.