The distance of {TAIL ~ each roller} from {HEAD ~ the rotation axis} and the angles between adjacent rollers are predetermined such that, at any time during a rotation cycle, two rollers engage at least one currently active tooth 
The distance of { TAIL ~ each roller } from { HEAD ~ the rotation axis } and the angles between adjacent rollers are predetermined such that , at any time during a rotation cycle , two rollers engage at least one currently active tooth
OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH