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 output shaft. The insight shaft attaches to an eccentric drive member that induces eccentric rotation of the cycloidal cam. In compound reducers, the first tabs on the cycloidal cam lobes engages cam supporters in the housing. Cylindrical cam followers become teeth on the inner gear, and the amount of cam followers exceeds the number of cam lobes. The next track of compound cam lobes engages with cam fans on the result shaft and transforms the cam’s eccentric rotation into concentric rotation of the output shaft, thus raising torque and reducing speed.
Compound cycloidal gearboxes offer ratios ranging from as low as 10:1 to 300:1 without stacking phases, as in regular planetary gearboxes. The gearbox’s compound reduction and will 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 slow 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 basic design principles but generate cycloidal motion in different ways.
Planetary gearboxes
Planetary gearboxes are made up of three simple 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 input shaft, which is connected to the servomotor. The sun gear transmits motor rotation to the satellites which, subsequently, rotate inside the stationary ring equipment. The ring gear is section 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 gives the output shaft higher torque and lower rpm.
Planetary gearboxes generally have single or two-equipment stages for reduction ratios ranging from 3:1 to 100:1. A third stage could 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 number of teeth in the inner ring gear and nsun = the amount of teeth in the pinion (input) gear.
Benefits of cycloidal gearboxes
• Zero or very-low backlash stays 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 compact size
• Quiet operation

Ever-Power Cycloidal Gear technology is the far excellent choice when compared to traditional planetary and cam indexing devices.

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