Patent ID: 7485070

Claim:
A anti-backlash planetary gear system for a multi-channel fiber optic rotary joint comprising: a sun gear; three, or more planet gear assemblies; an internal gear; a carrier; an elastic annular ring symmetrically arranged encircling said sun gear and said planet gear assemblies; a steel holder with an annular slot on one side face to hold said elastic annular; each said planet gear assembly includes a first planet gear, a second planet gear, a pair of planet gear housings, a pair of bearings; each said first planet gear meshing with said sun gear; each said second planet gear meshing with said internal gear; each said first planet gear fixed with each said second planet gear coaxially; each said first planet gear and second planet gear being rotational coaxially relative to said planet gear housings; said internal gear being stationary; said sun gear being rotational coaxially relative to said internal gear through a pair of bearings; and said carrier being rotational coaxially relative to said internal gear through a pair of bearings.