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 track of the cycloidal cam lobes engages cam followers in the casing. Cylindrical cam followers become teeth on the inner gear, and the number of cam followers exceeds the number of cam lobes. The second track of compound cam lobes engages with cam supporters on the result shaft and transforms the cam’s eccentric rotation into concentric rotation of the result shaft, thus raising torque and reducing speed.
Compound cycloidal gearboxes provide ratios ranging from as low as 10:1 to 300:1 without stacking stages, 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 velocity output shaft (flange).
There are several commercial variations of cycloidal reducers. And unlike planetary gearboxes where variations are based on gear geometry, heat treatment, and finishing processes, cycloidal variations share fundamental design concepts but generate cycloidal motion in different ways.
Planetary gearboxes are made up of three simple 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 gear attaches to the insight shaft, which is connected to the servomotor. Sunlight gear transmits electric motor rotation to the satellites which, in turn, rotate inside the stationary ring gear. The ring gear is section of the gearbox housing. Satellite gears rotate on rigid shafts linked to the planet carrier and trigger the earth carrier to rotate and, thus, turn the result shaft. The gearbox provides output 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 could be added for even 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 internal ring equipment and nsun = the number of the teeth in the pinion (insight) gear.
Benefits of cycloidal gearboxes
• Zero or very-low backlash stays relatively constant during existence 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 excellent choice when compared to traditional planetary and cam indexing gadgets.
Perspective our on-line cycloidal gearbox gallery.