Cycloidal gearboxes
Cycloidal gearboxes or reducers consist of four fundamental components: a high-speed input shaft, an individual or compound cycloidal cam, cam followers or rollers, and a slow-speed cycloidal gearbox output shaft. The input shaft attaches to an eccentric drive member that induces eccentric rotation of the cycloidal cam. In substance reducers, the first track of the cycloidal cam lobes engages cam supporters in the housing. Cylindrical cam followers become teeth on the inner gear, and the amount of cam fans exceeds the number of cam lobes. The next track of substance cam lobes engages with cam followers on the result shaft and transforms the cam’s eccentric rotation into concentric rotation of the output shaft, thus increasing torque and reducing speed.
Compound cycloidal gearboxes offer ratios ranging from only 10:1 to 300:1 without stacking levels, as in standard planetary gearboxes. The gearbox’s compound reduction and can be calculated using:
where nhsg = the amount of followers or rollers in the fixed housing and nops = the number for followers or rollers in the gradual velocity output shaft (flange).
There are many commercial variations of cycloidal reducers. And unlike planetary gearboxes where variations are based on gear geometry, heat treatment, and finishing procedures, cycloidal variations share basic design concepts but generate cycloidal movement in different ways.
Planetary gearboxes
Planetary gearboxes are made of three simple force-transmitting elements: a sun gear, three or even more satellite or world gears, and an internal ring gear. In an average gearbox, the sun gear attaches to the insight shaft, which is connected to the servomotor. Sunlight gear transmits electric motor rotation to the satellites which, subsequently, rotate in the stationary ring gear. The ring equipment is section of the gearbox housing. Satellite gears rotate on rigid shafts linked to the earth carrier and cause the earth carrier to rotate and, thus, turn the result shaft. The gearbox gives the output shaft higher torque and lower rpm.
Planetary gearboxes generally have one or two-equipment stages for reduction ratios which range from 3:1 to 100:1. A third stage can be added for also 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 amount of tooth in the pinion (input) gear.
Great things about 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 compact size
• Quiet operation

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