Bevel gear 1 rotates about fixed axis C and meshes with bevel gear 2 which rotates about fixed axis D. Gear 2 is rigidly attached to spur gear 3 which meshes with gear 4, rigidly attached to the carrier designed as housing 5. Mounted freely on studs of housing 5 are bevel planet gears 6 which mesh with bevel sun gears 8 and 7 of equal diameter. Gears 7 and 8 are keyed to shafts A and B which are connected to driving links of the mechanism. When the driving links rotate in the same direction at the same speed, sun gears 7 and 8 rotate at the same speed as housing 5. If the driving links have different speeds, then, when gears 7 and 8 rotate, planet gears 6 rotate about their axes. The speeds n₁, n₇ and n₈ of gears 1, 7 and 8 are related by the equation n₁=((z₂z₄)/(z₁z₃))((n₇+n₈)/2)where z₁, z₂, z₃ and z₄ are the numbers of teeth of gears 1, 2, 3 and 4.
$2916$CxG,DR$