Internal gear 1 rotates about fixed axis A and meshes with planet gear 2 which is rigidly attached to planet gear 3. Gear 3 meshes with fixed internal gear 5. Carrier 4 rotates about axis A and is connected by a turning pair to planet gears 2 and 3. For links 1 and 4 to be coaxial, the numbers of teeth of gears 1, 2, 3 and 5 should satisfy the condition (if they have the same module): z₁+z₃=z₂+z₅. The speeds n₁ and n₄ of gear 1 and carrier 4 (in rpm) satisfy the condition n₄=-n₁(z₁z₃)/(z₂z₅-z₁z₃). For the relative sizes of the links shown, gear 1 and carrier 4 rotate in opposite directions.
$2875$CxG,PR$