Cycloidal gearboxes or reducers consist of four basic 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 track of the cycloidal cam lobes engages cam fans in the housing. Cylindrical cam followers act as teeth on the inner gear, and the amount of cam followers exceeds the amount of cam lobes. The next track of compound cam lobes engages with cam supporters on the output shaft and transforms the cam’s eccentric rotation into concentric rotation of the result shaft, thus raising torque and reducing rate.
Compound cycloidal gearboxes offer ratios ranging from as low as 10:1 to 300:1 without stacking levels, as in standard 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 slower acceleration output shaft (flange).
There are many 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 concepts but generate cycloidal motion in different ways.
Planetary gearboxes are made of three fundamental force-transmitting elements: a sun gear, three or even more satellite or planet gears, and an interior ring gear. In an average gearbox, the sun equipment attaches to the insight shaft, which is connected to the servomotor. The sun gear transmits engine rotation to the satellites which, in turn, rotate within the stationary ring gear. The ring gear is part of the gearbox casing. Satellite gears rotate on rigid shafts connected to the earth carrier and cause the planet carrier to rotate and, thus, turn the output shaft. The gearbox gives the result shaft higher torque and lower rpm.
Planetary gearboxes generally have single or two-equipment stages for reduction ratios which range from 3:1 to 100:1. A third stage can be added for even higher ratios, nonetheless it is not common.
The ratio of a planetary gearbox is calculated using the following formula:
where nring = the number of teeth in the inner ring equipment and nsun = the number of tooth in the pinion (input) gear.
Great things about cycloidal gearboxes
• Zero or very-low backlash stays relatively constant during lifestyle 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 may be the far superior choice in comparison with traditional planetary and cam indexing devices.
Have you or participants of your family thought about cycloidal gearbox?