Eccentric 1 rotates about fixed axis A and is encircled by the collar of gear 2 which meshes with internal gear 5. Gear 5 rotates about axis A. Gear 2 has yoke 3, secured to the gear by screws 4, which prevents rotation of the gear. When eccentric 1 rotates, gear 2 has a circular translational motion and drives gear 5. The speeds n₁ and n₅ of eccentric 1 and gear 5 (in rpm) are related by the equation n₅=n₁(z₅)/(z₅-z₂) where z₂ and z₅ are the numbers of teeth of gears 2 and 5. The transmission ratio becomes very high when there is only a small difference between the numbers of teeth of gears 2 and 5.
$2899$CxG,PR$