Abstract: A centring drum for filter assembly machines, the centring drum having external axial seats movable with the centring drum about a longitudinal axis of rotation, and for receiving respective double filters, at least some of which are offset laterally, along the relative seats, with respect to a central transverse reference plane; each seat housing a respective stop member movable with the relative seat about the longitudinal axis of rotation, and located on a respective side of the reference plane to define a centred position of the relative double filter, and a push device for moving the relative double filter axially onto the relative stop member; the stop members defining a first and a second succession of stop members, which are located on opposite sides of the reference plane and are both connected to a position adjusting device movable about the longitudinal axis of rotation and for moving the two successions equally and oppositely along the longitudinal axis of rotation.

Abstract: A centring drum for filter assembly machines, the centring drum having external axial seats movable with the centring drum about a longitudinal axis of rotation, and for receiving respective double filters, at least some of which are offset laterally, along the relative seats, with respect to a central transverse reference plane; each seat housing a respective stop member movable with the relative seat about the longitudinal axis of rotation, and located on a respective side of the reference plane to define a centred position of the relative double filter, and a push device for moving the relative double filter axially onto the relative stop member; the stop members defining a first and a second succession of stop members, which are located on opposite sides of the reference plane and are both connected to a position adjusting device movable about the longitudinal axis of rotation and for moving the two successions equally and oppositely along the longitudinal axis of rotation.

Abstract: In a filter tip attachment machine, filter rods (2) are taken up from a hopper by a roller (5) furnished with longitudinal flutes (7), each accommodating one rod (2) and operating in conjunction with one or more rotating disc cutters (11) by which the rods (2) are divided into two or more plugs (10); the flutes (7) are sectional, incorporated into a set of axially slidable modules (17, 20, 23) ensheathing the take-up roller (5) and adjustable for position along the rolling surface according to the number of plugs (10) that will be cut from the rod (2), or to the length of the single plug (10), or both.