Abstract: Provided is a offset web press, particularly a variable cutoff type web press, which can reduce costs of replacement of a sleeve for a printing cylinder, which is deteriorated through printing operation. The sleeve for a printing cylinder, which is cylindrical and which is fitted on the outer periphery of a base shaft roll provided on the body side of the printing machine, is composed of an inner peripheral layer having a plurality of layers at least one of which is expandable or contractible with respect to a radial load, and an outer peripheral cylinder closely fitted on the outer peripheral surface of the inner peripheral layer, the inner peripheral layer and the outer peripheral layer being formed separate from each other so as to be separatable from each other.

Abstract: An object is to provide a printing press that has a printing plate with a changeable diameter and that can sufficiently prevent oil and oil mist from entering a printing unit. A rotary press (1) having a blanket cylinder (17) with a changeable diameter is provided.

Abstract: An object is to provide a rotary press that copes with a variation in the positions of printing cylinders and that includes a safety device having a simple structure. The rotary press has a cut-off length of a web (11) that is variable by changing diameters of a plate cylinder (15) and a blanket cylinder (17), the rotary press including a printing section (6) including the plate cylinder (15) and the blanket cylinder (17); an ink-applying roller (20); and a safety device provided in the vicinity of the printing section (6). The safety device includes a safety bar mechanism (37) that stops the operation upon detecting intrusion of an object to a contact area of the plate cylinder (15) and the blanket cylinder (17) and/or a safety cover (30) that is provided to shield the plate cylinder (15), the ink roller (20) and the blanket cylinder (17), from the outside.

Abstract: A first guide roll, a second guide roll and a backing roll are mounted on a movable frame. A feed roll is disposed substantially perpendicularly below the second guide roll upstream of the second guide roll relative to a direction of movement of a base sheet. The distance between the feed roll and the second guide roll is ninety (90) to two hundred and ten (210) times as long as a distance of travel of the backing roll when the backing roll is moved away from a coating roll.

Abstract: The distance between a D-roll and a C-roll is switched at proper time intervals between two stages in which the distance is larger or smaller. A thicker coating layer on the C-roll with the thickness controlled by the larger distance between the D-roll and the C-roll is transferred onto a base sheet in a condition in which the C-roll and a B-roll are in contact with each other with the base sheet interposed therebetween. The distance between the C-roll and the B-roll is increased when a thinner coating layer on the C-roll with the thickness controlled by the smaller distance between the D-roll and the C-roll reaches a transfer position, so that the coating layer is not transferred onto the base sheet. A local increase of the amount of the coating material applied at the end of a coating area can be prevented, and the thickness of the coating material applied can be controlled to be constant with high accuracy over the entire coated area.