Model: G04 Double Planet and Ring Gear Train
This model consists of two ring and planet gears coupled together. One set has 40 teeth on the planet and 120 teeth in the ring gear. The other set has 36 teeth and 116 teeth in the ring gear. The two smaller gears are ganged together. Since the two sets have different tooth ratios of 3 and 3.22 the outer ring gears move in a differential motion relative to one another. The rod in the back is used to ground one of the ring gears using the pedestal model H-1. See models G-2 and G-3 for further discussion of planetary gear trains.

Francis Moon 2003-07-01

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