Gear 2 is keyed to shaft 1, rotates about fixed axis A and meshes with planet gears 3. Each gear 3 is rigidly attached to (or integral with) a planet gear 6. Gears 3 and 6 have an annular projection a which enters grooves b in internal gear 5 and in ring 7 which is keyed to shaft 1. Annular projection a rolls and slides in grooves b and thereby takes the place of the carrier in the planetary mechanism. Planet gears 3 mesh with fixed internal gear 4, and planet gears 6 with internal gear 5 which rotates about axis A. The numbers of teeth of gears 3, 4, 5 and 6 are related by the conditions z₃=z₆-1 and z₅=z₄+1. Besides, for links 2 and 5 to be coaxial, the numbers of teeth of gears 2, 3, 4, 5 and 6 should satisfy the conditions (if the gears have the same module): z₂+2z₃=z₄ and z₅-z₆=z₄-z₃. The speeds n₂ and n₅ of gears 2 and 5 satisfy the condition n₅=n₂(z₂z₃z₅-z₂z₄z₆)/(z₂z₃z₅+z₃z₄z₅) where z₂, z₃, z₄, z₅ and z₆ are the numbers of teeth of gears 2, 3, 4, 5 and 6. Gears 2 and 5 rotate in the same direction.
$2878$CxG,PR$