Abstract: In a sheet gripper, a dimensionally stable base material and an elastic clamping surface material are connected to each other in a form-fitting manner. The elastic clamping surface material functions as a clamping surface of the sheet gripper. This forms a sheet gripper having a long service life and is easy manufacture.

Abstract: A sheet-fed rotary printing press for selective recto printing and recto and verso printing includes a three-drum reversing device having three cylinders cooperatively disposed behind one another between respective impression cylinders of two adjacent printing units. The three cylinders include one at least double-size transfer cylinder, one at least double-size storage drum, and one at least single-size reversing drum. Grippers prescribe a circular periphery of the transfer cylinder. The transfer cylinder has an outer contour smaller than the circular periphery prescribed by the grippers of the transfer cylinder. Other grippers prescribe a circular periphery of the reversing drum. The reversing drum has an outer contour smaller than the circular periphery prescribed by the grippers of the reversing drum. A method of operating the three-drum reversing device is also provided.

Abstract: A method of varying a drum profile of a vario drum for transporting printing material sheets, in which shell segments of the vario drum are pivoted inward and outward. Sheet supporting elements assigned to the shell segments are reversibly deformed by pivoting the shell segments. A vario drum suitable for implementing the method and a machine containing the vario drum for processing printing material sheets contain the shell segments and the associated sheet supporting elements.

Abstract: A machine for processing printing material sheets, in particular a sheet-fed printing press, has a sheet transport drum for transporting the printing material sheets and at least one sheet supporting element. The sheet supporting element, which is formed with a sheet supporting surface, is compatible with the sheet transport drum, for supporting the printing material sheets in a first operating mode. When the machine is operated in the first operating mode the sheet supporting element is held attached to the sheet transport drum, and when the machine is operated in a second operating mode the sheet supporting element is stored in the machine detached from the sheet transport drum. A corresponding printing material processing machine is suitable for carrying out the novel method.

Abstract: A printing-material-carrying surface, having micro-elevations which make contact with a printing material provided with printing ink, is at least partly provided, preferably substantially only at peaks of the micro-elevations, with a fluid additive to improve print quality, in particular in recto and verso printing. The fluid additive, in particular a liquid additive diluting the printing ink and/or delaying and/or slowing the drying of the printing ink, is at least partly transferred to the printing material by the surface. A printing press cylinder and a printing press having the printing-material-carrying surface and a process for applying a fluid additive and a printing process using the printing-material-carrying surface, are also provided.

Abstract: A gripper system for a machine that processes printing material sheets has a gripper with a first clamping surface and a gripper pad, for cooperating with the gripper, with a second clamping surface. One of the two clamping surfaces is formed with a surface relief. The clamping surface which has the surface relief is placed in such a way that, when a narrow printing material sheet is gripped, the clamping surface is covered by the sheet only within a subregion of the clamping surface and, when it grips a broad printing material sheet, it is covered by the latter beyond the subregion. The surface relief is structured differently within the subregion than outside the subregion, in that it is provided within the subregion with an antideformation structure which protects the narrow printing material sheet from excessive clamping deformation.

Abstract: In a sheet gripper, a dimensionally stable base material and an elastic clamping surface material are connected to each other in a form-fitting manner. The elastic clamping surface material functions as a clamping surface of the sheet gripper. This forms a sheet gripper having a long service life and is easy manufacture.

Abstract: In a gripper system having grippers disposed in a row and interspaces between the grippers and hold-downs for holding down in each case a free edge of a printing material sheet gripped by the grippers, the hold-downs being disposed to project into the interspaces and being mounted such that they can be displaced together with the grippers when gripping the printing material sheet.

Abstract: A control system for a printing machine and a safety device for scanning and displaying a hazardous area that cannot be looked at on a printing machine and method thereof includes permitting the printing machine to be started up only after an acknowledgement through a control device that the hazardous area displayed has been examined by an operator.

Abstract: A gripper device in a sheet-processing machine includes a gripper, a gripper pad associated with the gripper and a first drive for moving the gripper out of an opened position thereof into a closed position thereof. The gripper is cooperatively engageable with the gripper pad for producing a clamping force for holding sheets being processed. A second drive is separately operable from the first drive during a production printing operation of the sheet-processing machine. The first and second drives are operable for positioning the gripper and/or the gripper pad so that clamping faces of one of the gripper and/or the gripper pad are movable by the second drive perpendicularly to clamping faces of the other of the gripper and/or the gripper pad.

Abstract: A machine for processing printing material sheets, in particular a sheet-fed printing press, has a sheet transport drum for transporting the printing material sheets and at least one sheet supporting element. The sheet supporting element, which is formed with a sheet supporting surface, is compatible with the sheet transport drum, for supporting the printing material sheets in a first operating mode. When the machine is operated in the first operating mode the sheet supporting element is held attached to the sheet transport drum, and when the machine is operated in a second operating mode the sheet supporting element is stored in the machine detached from the sheet transport drum. A corresponding printing material processing machine is suitable for carrying out the novel method.

Abstract: A gripper system for a machine that processes printing material sheets has a gripper with a first clamping surface and a gripper pad, for cooperating with the gripper, with a second clamping surface. One of the two clamping surfaces is formed with a surface relief. The clamping surface which has the surface relief is placed in such a way that, when a narrow printing material sheet is gripped, the clamping surface is covered by the sheet only within a subregion of the clamping surface and, when it grips a broad printing material sheet, it is covered by the latter beyond the subregion. The surface relief is structured differently within the subregion than outside the subregion, in that it is provided within the subregion with an antideformation structure which protects the narrow printing material sheet from excessive clamping deformation.

Abstract: A method of varying a drum profile of a vario drum for transporting printing material sheets, in which shell segments of the vario drum are pivoted inward and outward. Sheet supporting elements assigned to the shell segments are reversibly deformed by pivoting the shell segments. A vario drum suitable for implementing the method and a machine containing the vario drum for processing printing material sheets contain the shell segments and the associated sheet supporting elements.

Abstract: A method and an apparatus for reversing sheet material in a sheet-processing machine having at least two printing units, a reversing drum with a gripper system, and an impression cylinder that can be operated as a storage drum in perfecting mode and to which a further gripper system for one edge of the sheet material is assigned. In perfecting mode, one of the edges of the sheet material is gripped at an angular offset before the transfer centerline between the reversing drum and the storage drum, before the edge of the sheet material fixed to the storage drum is released.

Abstract: In a gripper system having grippers disposed in a row and interspaces between the grippers and hold-downs for holding down in each case a free edge of a printing material sheet gripped by the grippers, the hold-downs being disposed to project into the interspaces and being mounted such that they can be displaced together with the grippers when gripping the printing material sheet.

Abstract: A gripper device in a sheet-processing machine includes a gripper, a gripper pad associated with the gripper and a first drive for moving the gripper out of an opened position thereof into a closed position thereof. The gripper is cooperatively engageable with the gripper pad for producing a clamping force for holding sheets being processed. A second drive is separately operable from the first drive during a production printing operation of the sheet-processing machine. The first and second drives are operable for positioning the gripper and/or the gripper pad so that clamping faces of one of the gripper and/or the gripper pad are movable by the second drive perpendicularly to clamping faces of the other of the gripper and/or the gripper pad.

Abstract: A sheet-fed rotary printing press for selective recto printing and recto and verso printing includes a three-drum reversing device having three cylinders cooperatively disposed behind one another between respective impression cylinders of two adjacent printing units. The three cylinders include one at least double-size transfer cylinder, one at least double-size storage drum, and one at least single-size reversing drum. Grippers prescribe a circular periphery of the transfer cylinder. The transfer cylinder has an outer contour smaller than the circular periphery prescribed by the grippers of the transfer cylinder. Other grippers prescribe a circular periphery of the reversing drum. The reversing drum has an outer contour smaller than the circular periphery prescribed by the grippers of the reversing drum. A method of operating the three-drum reversing device is also provided.

Abstract: A method and an apparatus for reversing sheet material in a sheet-processing machine having at least two printing units, a reversing drum with a gripper system, and an impression cylinder that can be operated as a storage drum in perfecting mode and to which a further gripper system for one edge of the sheet material is assigned. In perfecting mode, one of the edges of the sheet material is gripped at an angular offset before the transfer centerline between the reversing drum and the storage drum, before the edge of the sheet material fixed to the storage drum is released.

Abstract: A control system for a printing machine and a safety device for scanning and displaying a hazardous area that cannot be looked at on a printing machine and method thereof includes permitting the printing machine to be started up only after an acknowledgement through a control device that the hazardous area displayed has been examined by an operator.

Abstract: A device for controlling vacuum applied to suction openings formed in a cylinder, the suction openings being connectable to a vacuum source via valves arranged in rows and assigned to the suction openings, includes a rotatable adjusting shaft carrying adjusting elements assigned to the valves, the adjusting elements serving to actuate the valves in a defined sequence when the adjusting shaft is rotated, the valves having adjusting bodies therein movable by the adjusting elements out of a first switching position of the adjusting bodies into a second switching position thereof, the vacuum applied to the suction openings being of different magnitudes in the first and the second switching positions; and a method for incrementally actuating the vacuum-controlling device.