Cycloidal gearboxes
Cycloidal gearboxes or reducers contain four simple components: a high-speed input shaft, a single 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 substance reducers, the first an eye on the cycloidal cam lobes engages cam supporters in the casing. Cylindrical cam followers become teeth on the inner gear, and the number of cam fans exceeds the number of cam lobes. The second track of compound cam lobes engages with cam supporters on the result shaft and transforms the cam’s eccentric rotation into concentric rotation of the result shaft, thus raising torque and reducing velocity.
Compound cycloidal gearboxes offer ratios ranging from as low as 10:1 to 300:1 without stacking stages, as in regular cycloidal gearbox planetary gearboxes. The gearbox’s compound decrease and can be calculated using:
where nhsg = the amount of followers or rollers in the fixed housing and nops = the quantity for followers or rollers in the slow velocity output shaft (flange).
There are many commercial variations of cycloidal reducers. And unlike planetary gearboxes where variations derive from gear geometry, heat therapy, and finishing processes, cycloidal variations share simple 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 even more satellite or world gears, and an interior ring gear. In a typical gearbox, the sun equipment attaches to the insight shaft, which is linked to the servomotor. The sun gear transmits motor rotation to the satellites which, in turn, rotate in the stationary ring gear. The ring gear is part of the gearbox housing. Satellite gears rotate on rigid shafts linked to the earth carrier and cause the planet carrier to rotate and, thus, turn the output shaft. The gearbox provides result shaft higher torque and lower rpm.
Planetary gearboxes generally have single or two-gear stages for reduction ratios which range from 3:1 to 100:1. A third stage can be added for actually higher ratios, nonetheless it is not common.
The ratio of a planetary gearbox is calculated using the following formula:
where nring = the amount of teeth in the internal ring gear and nsun = the number of teeth in the pinion (insight) gear.
Great things about cycloidal gearboxes
• Zero or very-low backlash remains relatively constant during existence of the application
• Rolling rather than sliding contact
• Low wear
• Shock-load capacity
• Torsional stiffness
• Flat, pancake design
• Ratios exceeding 200:1 in a concise size
• Quiet operation

Ever-Power Cycloidal Gear technology is the far excellent choice in comparison with traditional planetary and cam indexing products.