Adjustable cleaning of fibers in a spiralled air path and apparatus

A method for enabling the cleaning of fibers in a fiber cleaning machine in which a cleaning stream moves tufts around a rotating cleaning cylinder, the tufts being cleaned and opened. The cleaning action can be adapted to fibers of varying origin and to an increasing degree of opening in the course of cleaning. The cleaning stream is, to a large extent, controlled and controllable by decoupling it from the dynamic behavior of the transport streams which transport material to and away from the cleaning process. Compensation for variations in the cleaning stream, and in the material supplied for cleaning, are achieved by control of the cleaning intensity, in order that the tufts emerging from the cleaning process are constant and optimally cleaned and opened. The invention concerns also suitable fiber cleaning apparatus for the realization of the described method. The apparatus includes a cleaning cylinder positioned in a casing and a plurality of cleaning elements extending from the cylinder. The length, shape and density of the elements can change along the length of the cleaning cylinder so that the cleaning intensity varies along the length of the cylinder. Adjustable grid bars can be positioned below the cleaning cylinder.