Cutting unit comprising a stationary frame, a cutting drum, and an anvil drum

摘要

A cutting unit according to the invention comprises a stationary frame (1), a cutting drum (5) having a cutting knife (7) on an outer cylindrical surface thereof and a central axis, and an anvil drum (6) having an outer cylindrical surface and a central axis. The cutting drum (5) and the anvil drum (6) are arranged one over the other with parallel centre axes for cutting web material fed between them. The upper of the cutting drum (5) and the anvil drum (6) is centred on an arbour, which is rotatable supported in the stationary frame and connectable to a driving device for rotating the arbour and the upper drum around the centre axis thereof. The lower of the cutting drum and the anvil drum is arranged rotatable around the centre axis thereof, and is arranged movable towards and away from the upper drum. The cutting unit further comprises a carrier (16), which is arranged movable towards and away from the upper drum. The carrier (16) comprises at least two contact rollers (19), which have an outer cylindrical surface and which are arranged rotatable round a respective axis in the carrier, which axes are parallel to the centre axis of the cutting drum (5) and the anvil drum (6). The lower drum is shaftless and is arranged with the outer cylindrical surface thereof resting on the outer cylindrical surface of the at least two contact rollers (19), wherein at least one contact roller (19) is situated on either side of a central vertical plane of the lower drum for providing vertical and transversal support of the lower drum by the contact rollers only. The carrier (16) is connectable to a pressing device for moving and pressing the carrier (16) and the lower drum carried thereby towards and against the upper drum for providing cutting pressure between the upper drum and the lower drum.