PURPOSE: To minimize the number of temporary products for the production buffer by monitoring the relaxation of the sliver between the carding frame and the sliver-delivery unit and controlling the slowdown, stoppage, restarting, and acceleration of the sliver-delivery unit on the basis of the monitoring.

CONSTITUTION: There is a predetermined overproduction from a cardframe 10 and/or a drawframe relative to a spinning machine. On the basis of the detection of the sliver loop sensor 12 between them, the controlling machine 13 reduces the speed of the sliver-delivering unit 11 in the cardframe, stops it, if necessary, and then restarts and accelerates it.