Abstract: Devices for turning sheets in a rotary printing machine are described. The devices have a storage drum for handling sheets, which are each held by a holding device, and a turning drum is disposed downstream of the storage drum and has a holding device for engaging a rear edge of the sheet to be turned. An operation of detaching the sheet to be turned from the storage drum and carrying it along by the turning drum leads to the formation of a pressure reduction in an area formed between the sheet to be turned, the storage drum and the turning drum. The pressure reduction is compensated for by supplying ambient air, blast air and/or compressed air. The turning device has a channel and/or a passage orifice connected to an inner chamber of the turning drum. Via the channel and/or passage orifice air can be sucked and/or blown into the reduced-pressure area.

Abstract: A device for positively coupling one force transmission element with a further force transmission element includes a multi-disk clutch formed of at least four disk rings for adjusting the rotary position of the further transmission element in relation to the one force transmission element, the disk rings being axially displaceably mounted and, for both directions of rotation, having a play-free operative connection with the force transmission elements.

Abstract: An apparatus for guiding and transferring a sheet in a printing machine from a first cylinder to a gripper of a second cylinder in which the apparatus has a guide device for a holding element, which is held outside the first and second cylinder. In this way, the design of the guide apparatus can be independent of the first and second cylinders. In addition, a longer time period is available for gripping, tensioning and transferring the sheet. The apparatus can be used both in a recto printing machine and in a turner device in recto and verso printing.

Abstract: A smoothing device includes guide surface sections for a flat printing material whose leading edge is pulled in a direction of travel over the guide surface sections. The guide surface sections have openings which communicate with throttling ducts that are pressurized with compressed air during operation. The guide surface sections form a smoothing notch and have air passage openings which communicate with a flow duct. The air passage openings are configured to cause pressure conditions when there is an air throughflow during operation such that the flat printing material forms a bead projecting into the smoothing notch.

Abstract: A machine for processing sheets, in particular a sheet-fed rotary printing machine, includes a transporting cylinder for transporting the sheets and having air nozzles disposed offset in relation to one another in a direction other than an axis-parallel direction of the transporting cylinder, and having a directing configuration for directing the sheets and having air nozzles, the configuration being assigned to the transporting cylinder. The machine is distinguished in that the air nozzles include throttled air nozzles and unthrottled air nozzles.

Abstract: In a device for reducing the frictional force between a guiding or carrying element for sheets in a sheet-processing machine, in particular rotary printing machines, guiding and carrying elements acted upon by throttled blowing air include a sheet surface, orifices fluidically connected to a hollow interior, and a throttle disposed in the hollow interior. The elements are to be connected to an air source for blowing air out through the orifices and for generating an air cushion between a sheet and the sheet surface. Each of the orifices is preceded by the throttle with respect to a direction of air from the air source.

Abstract: In a device for guiding sheets in a sheet-fed apparatus, preferably, a rotary printing press, sheet guide elements that are charged with blasted air are disposed at the sheet guide cylinder, and the air blast nozzles include a combination of conventional free jet nozzles and throttled nozzles, which are independently charged with different pressure levels.

Abstract: In a method for conveying sheets in a sheet-printing machine, the sheets are held securely in position on a circumferential surface of sheet-guiding cylinders with the aid of an adhesive, which can be detached again a number of times and does not transfer itself onto the sheets, and are conveyed through the printing stations of the printing machine. For transport without using grippers, the sheets are held in an area of their front and rear edges only by the adhesive, and are lifted off the circumferential surface of the impression cylinders with the aid of a sheet-lifting device in order for the front edge to be transferred to a downstream sheet-guiding cylinder. Lifting the sheets off the circumferential surface of the cylinders results in a peel-off effect, by which the adhesive bond can be readily released again.

Abstract: For invention enables torque-compensation of alternating interference-torques in a printing machine. The printing machine, in particular a sheet-fed printing press, has one or more processing stations with cylinders and drums and at least one gear train. The gear train is formed with multiple gear-wheels that drive the cylinders and drums. In a first configuration there is provided an elastic coupling between two equidirectionally rotating gear-wheels. In a second configuration there is provided an elastic crank on a gear-wheel. There is thus impressed onto gear wheel or gear wheels, an additional and variable torque, in addition to the driving-torque of the printing machine.

Abstract: A method of operating a sheet-fed rotary printing machine includes mounting at least one rotating cylinder to be coupled to a drive or fixed relative to a framework, and moving an actuator to both uncouple the cylinder from the drive and fix the cylinder relative to the framework. A sheet-fed rotary printing machine includes a framework, a drive, at least one cylinder rotatably mounted to the framework, the cylinder is to be coupled to the drive or fixed relative to the framework, and a fixing and coupling configuration connected to the cylinder to both uncouple the cylinder from the drive and fix the cylinder relative to the framework.

Abstract: A sheet transport cylinder in a machine that processes sheets of printing material includes air nozzles for sheet formats of the printing-material sheets. The printing-material sheets are dimensioned from a minimum format up to a maximum format. The sheet transport cylinder is distinguished by the fact that the air nozzles are throttled air nozzles disposed to be matched to the minimum format.

Abstract: A guiding device in a machine for processing sheets of printing material includes unthrottled air nozzles for contact-free guidance of the sheets, and throttled air nozzles arranged at locations which are prone to contact by the sheets; and a machine for processing sheets of printing material and a sheet-fed rotary printing machine, respectively, having the guiding device.

Abstract: A device for transferring a sheet via a peripheral region of a cylinder includes an airflow-generating device for applying at least one air flow to the peripheral region of the cylinder, with which the sheet is associated, the airflow being directed in a direction of rotation of the cylinder; and a method of operating the device for transferring a sheet via a peripheral region of a cylinder.

Abstract: A sheet sensor arrangement for a sheet printing machine and particularly for a turning device of a sheet printing machine, which comprises at least one hollow cylindrical drum (3; 4), which has a gripper system to transport and/or temporarily store individual sheets (5). A sensor arrangement which is not very susceptible to contamination and has a mechanically simple structure is comprised of the fact that the cylindrical wall of the drum (3; 4) has at least one opening which allows light to pass through, and that a sheet sensor is formed by a light barrier (9, 10, 11), which has a light beam which, in at least one angle position of the drum, is directed from the inside at the opening which allows light to pass through. In addition, a corresponding process for optical monitoring of sheets in a sheet printing machine is indicated.

Abstract: A sheet sensor device for a sheet-fed printing press having a sheet-reversing arrangement, said sheet-reversing arrangement being comprised essentially of a storage drum, a reversing drum and gripper systems mounted on these drums, so that a sheet sensor device comprising a transmitter and a receiver is arranged in the sheet-reversing area formed between the storage drum and the reversing drum, and that the transmitter is arranged on the one side of the printing machine, and the receiver is arranged on the other side of the printing machine, outside of the sheet-travel area.

Abstract: A rotary sheet-fed printing press for recto and verso printing has a turning drum disposed between impression cylinders having double the diameter of a conventional blanket cylinder, wherein a sheet gripped at a leading edge thereof by grippers of a first one of the impression cylinders is gripped at a trailing edge thereof by grippers of the turning drum upon transfer of the sheet to the turning drum. In the turning drum, suction nozzles are provided which suck the sheet, guided on the one impression cylinder, towards the turning drum in the vicinity of the trailing edge of the sheet and, in so doing, smooth it diagonally and peripherally on the circumference of the one impression cylinder, before the grippers of the turning drum which grip the sheet by the trailing edge thereof are closed, and the grippers of the one impression cylinder which grip the sheet by the leading edge thereof are opened.