Abstract: A printing unit comprises an impression cylinder (3) and an inking roller (4) adjustably spaced from the impression cylinder (3) by means of a pair of first lever arms (10) which are pivotal and eccentrically mounted in relation to the axis of rotation (18) of the roller (4). An elongate doctor blade (8) for wipe-off engagement with the roller (4) is supported by a pair of second pivotal lever arms (19) which are concentrically mounted in relation to the axis of rotation (18) of the roller (4) and eccentrically mounted in relation to the fulcrum (15) of the first lever arms (10), whereby the doctor blade (8) and the roller (4) maintain their relative positions during the adjustment of the spacing between the roller (4) and the impression cylinder (3). Thus, the doctor blade (8) follows the movements of the inking roller (4) while maintaining the parallelism between them. The pivotment and the setting of the lever arms (10) and (19) are brought about by adjusting devices (16) and (23), respectively.

Abstract: An arrangement in a bag-making machine for forming bag-defining lines of perforation and weld lines in an elongate web (7) comprises a driven roller nip including a nip roller (4) and a backup roller (5), by means of which the web (7) is fed through the machine (1), an elongate cutter (10) which is parallel to the rollers (4, 5) and rotatable about its longitudinal axis, and which when rotated is moved into engagement with the back-up roller (5) for making the lines of perforation, and two welding units (8) with sealing jaws (22) for making the weld lines. In order to allow optional adjustement of the spacing between consecutive lines of perforation and weld lines, the cutter (10) is separately connectible and disconnectible independently of the operation of the roller nip (4, 5) or of other drive means in the machine (1).

Abstract: In a method for manufacturing rolls of bags, a web having transverse lines of perforation is wound by means of a winding device. A leading end of the web is first conducted into the winding device which is activated for the winding operation. When a predetermined web length has been sensed, a clamping device clamps the web which is immediately torn off, and a new leading web end is gripped after a certain time delay by means of a gripping device. The finished roll of bags is thereafter released from the winding device which is reset for a new winding operation. Finally, the gripping device is moved past the winding device so that this can catch the web and commence a new winding cycle.