Page 272 - Steam Turbines Design, Applications, and Rerating

(a)

(b)

(c)
Figure 13.8 Epicyclic gear types: (a) planetary gear, fixed annu-
lus system, input and output shafts rotate in same direction,
ratios from 3:1 to 12:1; (b) star gear, fixed carrier assembly, input
and output shafts rotate in opposite directions, ratios from 2:1 to
11:1; (c) solar gear, fixed sunwheel, input and output shafts
rotate in same direction, ratios from 1.1:1 to 1.7:1. (Philadelphia
Gear Corporation, King of Prussia, Pa.)
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