Cycloidal gearboxes or reducers consist of four fundamental components: a high-speed input shaft, a single or substance 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 followers in the housing. Cylindrical cam followers act as teeth on the inner gear, and the amount of cam supporters exceeds the amount 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 output shaft, thus raising torque and reducing rate.
Compound cycloidal gearboxes provide ratios ranging from only 10:1 to 300:1 without stacking levels, as in regular 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 gradual acceleration output shaft (flange).
There are several commercial variations of cycloidal reducers. And unlike planetary gearboxes where variations derive from gear geometry, heat therapy, and finishing procedures, cycloidal variations share basic design concepts but generate cycloidal movement in different ways.
Planetary gearboxes are made of three basic force-transmitting elements: a sun gear, three or even more satellite or planet 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 motor rotation to the satellites which, subsequently, rotate in the stationary ring equipment. The ring gear is portion 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 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 could be added for actually higher ratios, but 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 equipment and nsun = the number of teeth in the pinion (insight) gear.
Benefits of cycloidal gearboxes
• Zero or very-low backlash stays relatively constant during life 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 Equipment technology is the far excellent choice when compared to traditional planetary and cam indexing products.
View our on-line cycloidal gearbox gallery.