US Patent 9194480 Planetary gear alignment and indexing method and associated tool

A method is disclosed for assembly of a planetary gear drive, wherein the gear drive includes a ring gear, a sun gear, and a plurality of planet gears engaged with the ring gear and sun gear. The method includes mounting the planet gears within a carrier, with the planet gears freely rotatable relative to the carrier. A gear alignment tool is inserted through a bore in a front face of the carrier and is used to index the planet gears into an aligned rotational position for proper subsequent engagement with the ring gear and sun gear.