Abstract: One or both of the lap rollers on which a lap roll is mounted for unwinding purposes is driven with an increasing speed during the winding-off interval so as to maintain the thickness of the lap layer constant. This, in turn, maintains the count of the sliver to be formed in the comber at a constant number. The increase in the lap roller drive can be made dependent upon the length of the lap layer which is unwound from the roll, on the mass of the lap layer delivered to the comber or on the mass of a sliver produced from the combed lap as measured at a point downstream of the comber. The speed may be increased in a stepwise manner or continuously.

Abstract: The device for increasing the cohesion length of the slivers is embodied by a pair of calendar rollers. Each calendar roller has a plurality of transversely disposed protuberances of rounded shape for interengaging in spaced relation with each other in order to slightly crimp a sliver passing through the gap between the rollers. The protuberances are adapted to one another in gear-like manner.