Cycloidal gearboxes
Cycloidal gearboxes or reducers contain four Cycloidal gearbox simple components: a high-speed input shaft, an individual or compound cycloidal cam, cam followers or rollers, and a slow-speed output shaft. The input shaft attaches to an eccentric drive member that induces eccentric rotation of the cycloidal cam. In compound reducers, the first an eye on the cycloidal cam lobes engages cam fans in the casing. Cylindrical cam followers become teeth on the inner gear, and the amount of cam supporters exceeds the number of cam lobes. The second track of substance cam lobes engages with cam fans on the output shaft and transforms the cam’s eccentric rotation into concentric rotation of the result shaft, thus increasing torque and reducing velocity.

Compound cycloidal gearboxes provide ratios ranging from only 10:1 to 300:1 without stacking levels, as in standard planetary gearboxes. The gearbox’s compound reduction and may be calculated using:

where nhsg = the number of followers or rollers in the fixed housing and nops = the quantity for followers or rollers in the slower speed output shaft (flange).

There are several commercial variations of cycloidal reducers. And unlike planetary gearboxes where variations derive from gear geometry, heat treatment, and finishing procedures, cycloidal variations share fundamental design principles but generate cycloidal motion in different ways.
Planetary gearboxes
Planetary gearboxes are made of three fundamental force-transmitting elements: a sun gear, three or more satellite or world gears, and an interior ring gear. In a typical gearbox, the sun gear attaches to the input shaft, which is linked to the servomotor. The sun gear transmits electric motor rotation to the satellites which, in turn, rotate within the stationary ring gear. The ring gear is part of the gearbox housing. Satellite gears rotate on rigid shafts linked to the planet carrier and cause the planet carrier to rotate and, thus, turn the result shaft. The gearbox provides output shaft higher torque and lower rpm.