Worm 6 rotates about fixed axis A, perpendicular to the plane of the drawing, and meshes with worm wheel 1 which is keyed to shaft C. Also keyed to shaft C is gear 2 which meshes with planet gears 3. Gears 3 mesh with fixed internal gear 4 and are connected by turning pairs to carrier 5 which is keyed to shaft B. The speeds n₆ and n₅ of worm 6 and carrier 5 (in rpm) are related by the equation n₅=n₆(z₆/z₁)(z₂/(z₃+z₄)) where z₁ is the number of teeth of worm wheel 1, z₆ is the number of threads (starts) of worm 6, and z₂ and z₄ are the numbers of teeth of gears 2 and 4.
$2887$CxG,PR$