Processing unit for processing at least one filter strip and device with at least two such processing units

The preparation unit for preparing at least one filter tow strip (8) for producing filters of cigarettes, for example, has processing units (12,14,16,24,26) which are associated with the tow guide path and which are arranged basically one above the other so that at least the section of the tow guide path which extends in the region of the processing units is orientated at an angle to the horizontal, preferably approximately vertically. The preparation unit is constructed as a module (2) with a defined interface for the connection to at least one further preparation unit. Independent claims are included for the following: (1) a device for preparing filter tow material for producing filters for cigarettes, for example, with at least two preparation units; and (2) a system for producing filters for cigarettes, for example, from filter tow material, with at least one additional device for further processing of the filter tow strip.