Rotation is transmitted from shaft 1 of the carrier through studs a to bevel planet gears 2. Gears 2 mesh with bevel gears 3 which are rigidly attached (or integral with) bevel gears 4 and 5. Gears 4 and 5 mesh with bevel sun gears 7 and 6 which are keyed to shafts B and A. The ratio of the numbers of teeth of gears 4 and 7 is equal to that of gears 5 and 6. Consequently, when shafts A and B rotate in the same direction at the same speed, sun gears 6 and 7 rotate at the same speed and carrier shaft 1 is stationary. If the driving links, connected to shafts A and B, have different speeds, then the planet gears rotate on sluds a and shaft 1 rotates. Shafts A and B do not have to be coaxial. The speeds n₁, n₆ and n₇ of carrier shaft 1, and gears 6 and 7 (in rpm) are related by the equation n₁=(n₆+n₇)/2.
$2915$CxG,DR$