Cycloidal gearboxes or reducers consist of 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 tabs on the cycloidal cam lobes engages cam fans in the casing. Cylindrical cam followers act as teeth on the internal gear, and the amount of cam fans exceeds the number of cam lobes. The next track of substance cam lobes engages with cam fans on the result shaft and transforms the cam’s eccentric rotation into concentric rotation of the result shaft, thus raising torque and reducing acceleration.
Compound cycloidal gearboxes offer ratios ranging from as low as 10:1 to 300:1 without stacking phases, 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 sluggish rate 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 concepts but generate cycloidal motion in different ways.
Planetary gearboxes are made of three basic cycloidal gearbox force-transmitting elements: a sun gear, three or more satellite or planet gears, and an internal ring gear. In a typical gearbox, the sun equipment attaches to the input shaft, which is connected to the servomotor. The sun gear transmits engine rotation to the satellites which, in turn, rotate in the stationary ring gear. The ring equipment is part of the gearbox housing. Satellite gears rotate on rigid shafts connected to the planet carrier and trigger the earth carrier to rotate and, thus, turn the result shaft. The gearbox provides result shaft higher torque and lower rpm.
Planetary gearboxes generally have solitary or two-equipment stages for reduction ratios which range from 3:1 to 100:1. A third stage can be added for actually higher ratios, but it is not common.
The ratio of a planetary gearbox is calculated using the next formula:
where nring = the amount of teeth in the inner ring equipment and nsun = the number of tooth in the pinion (input) gear.
Benefits of cycloidal gearboxes
• Zero or very-low backlash remains relatively constant during lifestyle of the application
• Rolling instead of 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 superior choice when compared to traditional planetary and cam indexing gadgets.