Cycloidal gearbox

Cycloidal gearboxes
Cycloidal gearboxes or reducers consist of four basic 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 Cycloidal gearbox compound reducers, the first track of the cycloidal cam lobes engages cam fans in the casing. Cylindrical cam followers become teeth on the internal gear, and the amount of cam supporters exceeds the amount 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 result shaft, thus raising torque and reducing velocity.

Compound cycloidal gearboxes provide ratios ranging from as low as 10:1 to 300:1 without stacking phases, as in standard planetary gearboxes. The gearbox’s compound decrease and may be calculated using:

where nhsg = the number of followers or rollers in the fixed housing and nops = the number for followers or rollers in the sluggish 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 processes, cycloidal variations share simple design principles but generate cycloidal motion in different ways.
Planetary gearboxes
Planetary gearboxes are made of three basic force-transmitting elements: a sun gear, three or even more satellite or world gears, and an interior ring gear. In an average gearbox, the sun equipment attaches to the input shaft, which is linked to the servomotor. Sunlight gear transmits electric motor rotation to the satellites which, subsequently, rotate in the stationary ring gear. The ring equipment is part of the gearbox housing. Satellite gears rotate on rigid shafts linked to the earth carrier and trigger the planet carrier to rotate and, thus, turn the output shaft. The gearbox gives the output shaft higher torque and lower rpm.

Tags: