Ferguson’s paradox of gear drive 1

Input: blue carrier.
Output: green gear.
Zf: tooth number of stationary grey gear. Here Zf = 40.
Zg: tooth number of the green gear. Here Zg = 39.
Transmission ratio i = (Zf – Zg)/Zg. Here i = 1/39
The center distances between yellow gear and other large gears are the same despite the slightly different pitch diameters of each large gear. The “paradox” results from that.
The grey and yellow gears are standard ones.
The green gear are of corrected tooth profile. When cutting it, the tool moves from the gear center a little in comparison with standard gears.
The mechanism helps reduce velocity effectively.
Disadvantage: impossible to arrange more planet gears for force balancing the carrier.
See a prototype:
   • シンプルな高減速比の歯車機構 (Gear Mechanism with H...  

Inventor files of this video:
http://www.mediafire.com/file/38jpx44...