Abstract: A sheet-conveying device conveys a recording medium to a sheet support surface positioned downstream of the sheet-conveying device in a sheet-conveying direction when recording an image with an image-recording unit. A drive roller and a follower roller define a nip line therebetween. The nip line is positioned above the sheet support surface. A first support member rotatably supports the follower roller. A moving unit moves the first support member from a first position to a second position upstream of the first position in the paper-conveying direction immediately after a trailing edge of the recording medium leaves the sheet-conveying unit.

Abstract: A method and an apparatus for turning a sheet during its transport through a printing press permit improved printing results as a result of improved sheet guidance. A sheet is tautened following a transfer from a first transport device to a second transport device.

Abstract: A gripper system for controlling the loading and unloading of sheets on a cylindrical sheet guide. The gripper system comprises one or more grippers, which are positioned at an outer edge of the cylindrical sheet guide. Each gripper is coupled to a cam follower. The gripper system further comprises a cam, which is configured for affecting the elevation of the gripper(s) by moving the cam follower(s), and a servomotor, which is adapted for steering the cam. A cam-gripper controller is provided for controlling the servomotor according to a current printing profile.

Abstract: A device for printing two-dimensional parts, particularly plastic substrates, preferably plastic cards, having a depot comprising the parts to be imprinted, a printing station with a printing device, and a transport device for transporting the parts through the printing station, characterized in that aligning means serving the alignment of the parts on the transport device are provided in front of the printing station.

Abstract: A device is provided for transferring printed sheet material products including a gripper conveyor having a plurality of grippers for gripping a plurality of printed sheet material products, a sheet conveyor for receiving the plurality of products from the plurality of grippers in a lapped stream, and a plurality of fingers, each finger assigned to one of the plurality of grippers, each finger contacting a first side of one of the plurality of products when a second side of the plurality of products is in contact with the sheet conveyor. A method is also provided.

Abstract: A supply station for positioning enclosures on an enclosure-collating path of a mail-processing installation allows a simple conversion from operation for processing a stack of comparatively flexible, thin enclosures to operation for processing a stack of comparatively thick, essentially inflexible enclosures. The conversion is achieved using a magazine housing inside a supply station housing mounted so that it can be secured in two different pivot positions, whereby in one pivot position the lowermost enclosure of a stack of enclosures is bent using a vacuum arrangement in which the front end of the enclosure in the withdrawal direction can be gripped by a gripper, while in a second pivot position of the magazine housing, the front end in the withdrawal direction of a lowermost, comparatively thick and essentially inflexible enclosure is pushed by means of a pusher arrangement directly into the open claws of the gripper.

Abstract: This is a media transport apparatus using gripper segments that are connected to conveyor belts. These segments grip the leading edges of paper media and pull the media on a path toward a paper exit. Above the conveyor belts are baffle panels that have at least two panel separations. It is through these separations that the gripper segments move as the endless conveyor belts rotate. The gripper segments are provided with shifting structures that can laterally align the paper sheets. The leading edges of the paper are held between a gripper bar and elastomeric rollers.

Abstract: An apparatus for mounting and demounting a materials sheet onto and from a cylindrical surface of a drum (10) has clamps (40) pivotably arranged upon the sheet materials drum. The clamps have a first region (80) and a second region (70) either side of a pivot axis. The second region (70) clamps the materials sheet to the cylindrical surface (20) of the drum. A backbone (120) extends along the length of the drum and is removably attached to the drum. Push rods (90) movably arranged on the backbone are capable of being operated to push against the first region of the clamps to pivot the clamps to move the second region of the clamps. Any existing clasped materials sheet is thereby unclasped from the cylindrical surface.

Abstract: A drum for conveying a sheet has a cohesive sheet-guiding surface provided at little effort or cost and includes a drum body, a jacket forming a circumferential surface and a device for fixing the jacket onto the drum body. The jacket is located above a gap formed in the drum body so as to extend parallel to a longitudinal axis. The device for fixing the jacket includes at least one tensioning body that acts on the jacket in the region of the gap and is adjustable in radial direction.

Abstract: Various apparatus and methods for bending a sheet of media are disclosed.

Abstract: Disclosed is a clamping device (02) for fastening a plate (03) to the periphery of a cylinder (01). Said clamping device (02) comprises a first clamping element (04), a pivotally mounted second clamping element (06), a spring part (07), and a bracing element that is embodied as a pivotable spindle (08) and is movable between a clamping position in which the bracing element maintains the plate in a clamped state between the clamping elements and a released position in which the clamping elements release the plate. The spindle (08) is mounted in a groove so as to be displaceable, is fixed in an intermediate space between the spring part (07) and the second clamping element (06), and is pressed against the second clamping element by means of the spring part in the clamping position.

Abstract: An apparatus for stabilizing printed products being transported in a conveying stream over a distance hanging from clamps of a conveying device for transferring the printed products into a processing unit, wherein the clamps are of at least two parts including a clamp part which is movably controlled for opening and closing the clamp, and wherein between spaced-apart printed products a guide arrangement is provided which travels with the printed products and prevents a deflection of the printed products. The guide arrangement which includes the stabilizing elements is fastened at least to an immovable clamp part which interacts with the moveable clamp part, wherein the guide arrangement is moveable from an ineffective position into a support position behind the printed products which are being transported in the conveying direction.

Abstract: A device for conveying a sheet through a typographic or printing technology machine reliably transfers a sheet from a cylinder to a trailing-edge gripper system and includes a chain conveyor, grippers for holding and taking over the leading margin of the sheet from a cylinder and grippers fixed to endless chains for holding the trailing, rear margin of the sheet. When the grippers for the trailing margin pass the cylinder, the grippers are guided in a closed state along a path outside a revolution contour of a support surface and, having passed the cylinder, the grippers are guided in an open state along a path to a radial level of the rear margin held in auxiliary grippers.

Abstract: A media feedpath having a feed assist roller, comprises a media feedpath having a C-shaped portion, a media input and a feed roll nip, an input roller feeding media from the media input, a feed assist roller downstream of the C-shaped portion of the media feedpath, the feed assist roller assisting media indexing through the media feedpath on a single side and without an opposed pinch roller, the feed roll nip having a driven roller and a feed roll pinch roll opposite the driven roll, the feed assist roller being driven by a toggle gear transmission from the driven roller of the feed roll nip, the gear train adapted for toggling to operably engage or disengage the feed assist roller depending on a driving direction of the driven roller of the feed roll nip.

Abstract: A device for transferring print products comprises a circulating conveying element that includes clamps. A conveyor moves approximately in the same direction and synchronously below the conveying element, which includes grippers. A guide arrangement is provided in a transfer segment where the print products are transferred from the circulating conveying element to the conveyor. The guide arrangement includes spiral rotors having spiral sections respectively extending from opposite sides into spaces between the print products and which are effective in the conveying direction to stably position the print products. Activation devices operatively are arranged to open the clamps and close the grippers to effect the transfer of the print products from one of the clamps on the circulating conveying element to one of the grippers on the conveyor.

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: The paper-feeding mechanism includes a duplex drive roller disposed on a terminal end of a feeding path of an image-forming device for feeding paper and on a side of an output tray, a first idle roller for conveying the paper back to the output tray with the duplex drive roller after a single side of the paper is printed, a second idle roller for conveying the paper back to the output tray with the duplex drive roller after double sides of the paper are printed, and a stop means installed between the terminal end of the feeding path and the output tray for switching to a shut position to stop the paper when the paper is driven back to the feeding path and for switching to an open position when the paper is driven to the output tray after the double sides of the paper are printed.

Abstract: A system for printing an image on a printing media, comprising: a) an impression roller; b) a gripper which receives the printing media when said gripper is open, closes to hold the printing media to the impression roller while the image is printed, and opens to release the printing media from the impression roller; and c) at least one sensor which senses whether the gripper is open or closed.

Abstract: A paper thickness measuring device for use in a rotary paper feeding device having a rotating cylindrical drum. In a preferred embodiment of the present invention, a gripper is mounted on the cylindrical drum for gripping a sheet; and a target is mounted on the cylindrical drum and mechanically linked to the gripper such that a position of the target corresponds to displacement of the gripper by a gripped sheet. The target is arranged and configured for detection of the target position a predetermined time or at a downstream location after the gripper grips a sheet.

Abstract: A sheet guide apparatus includes a transfer cylinder, delivery chains, and sheet guide structure. The transfer cylinder holds a sheet. The delivery chains hold the sheet received from the transfer cylinder and conveys the sheet along a first convey path which is at least substantially arcuate. The sheet guide structure guides the sheet conveyed by the delivery chains. The sheet guide structure includes a movable guide member and stationary guide member. The movable guide member is movable between positions close to and spaced apart from the first convey path. The stationary guide member is stationarily arranged at a position spaced apart from the first convey path. When the movable guide member is close to the first convey path, a thin-sheet guide surface having a continuous substantially arcuate section is formed by only the movable guide member.

Abstract: A roller mechanism includes a pair of rollers and an urging unit. The pair of rollers oppose one another sandwiching a conveyance path of a sheet material, and are provided to be capable of increasing and reducing an axis-to-axis separation thereof. The urging unit urges at least one of the pair of rollers in a direction of reducing the axis-to-axis separation of the pair of rollers with an urging force that increases with an increase in the axis-to-axis separation of the pair of rollers, and presses the sheet material with the pair of rollers. The urging unit increases the urging force non-linearly, with a rate of increase of the urging force falling as the axis-to-axis separation of the pair of rollers increases within a range of changes at times of sheet material-pressing.

Abstract: The invention relates to a device for depositing notes, which comprises a plurality of storage compartments for depositing the notes, means for transporting the notes to the storage compartments and for the organized deposit of the same on stacks disposed in the storage compartments. The inventive device comprises one or more parallel revolving belts on which fingers are successively disposed in the longitudinal direction which cooperate with the belts to give receiving pockets for the notes. Every storage compartment is associated with a respective stripping element interposed between the storage compartment and the belts. For depositing a note in the storage compartment the belts and/or the corresponding stripping element can be adjusted relative each other in such a manner that the stripping element projects into the path of a note that is displaced by means of the belt.

Abstract: A sheet conveying device for conveying a sheet includes a displacement-amount detector configured to detect an amount of displacement of a conveyed sheet from a conveyance reference in a width direction being substantially perpendicular to a sheet conveying direction and a plurality of sheet conveying roller portions configured to be shiftable in a direction substantially perpendicular to the sheet conveying direction while pinching the sheet having the amount of displacement detected by the displacement-amount detector. Before the sheet reaches the sheet conveying roller portions, the sheet conveying roller portions are shifted based on the amount of displacement detected by the displacement-amount detector from a conveyance-reference position in a direction in which the sheet is displaced. After the sheet reaches the sheet conveying roller portions, the sheet conveying roller portions are shifted while pinching the sheet so as to reduce the amount of displacement.

Abstract: A feed conveyor feeds in flat items to a discharge conveyor that discharges the same. A joint upper belt conveyor extends across feed-in and discharge regions and has a lower belt section above the feed and discharge conveyors. An operating mechanism moves a lower belt section of the joint upper belt conveyor between: a first position in which a gap is formed between the lower belt section of the joint upper belt conveyor and the discharge conveyor that prevents the joint upper belt conveyor from making contact with the flat items on the discharge conveyor; and a second position in which the gap between the lower belt section of the joint upper belt conveyor and the discharge conveyor is such that the top of the flat item makes contact with the upper join conveyor belt.

Abstract: In a rotary feeder for conveying enclosures, in particular into conveying compartments of an enclosure-collating path, during operation, shocks within the gear mechanism of the drive unit of the feeder drum on account of gear mechanism play are avoided and the level of noise during operation is reduced in that a cam-actuated pair of claws (10, 11) is provided in each case at two diametrically opposite locations of the feeder drum (2) of the rotary feeder, and the cam (16) for actuating the pairs of claws is configured in sections (O) with an increasing in the radial spacing of its profile in accordance with a claw-opening movement counter to the prestressing force of prestressing means (19, 20) and, in sections (C) with a decrease in the radial spacing of its profile in accordance with a claw-closing movement under the prestressing force of the prestressing means, such that a braking moment on account of the claw opening counter to the prestressing force of the prestressing means, this braking moment being tr

Abstract: A shredder paper feed mechanism and paper feeder that, simply by setting a paper stack in the paper tray, enable a stack of document sheets to be fed to the shredder in an amount that matches the shredding capability of the shredder. This is done by using first and second rotating members equipped with claw members. The paper feed mechanism utilizes the transmitted rotary driving force of the shredder unit. The paper feed mechanism has a first rotating member having disc-shaped claw members with sharp portions for feeding the paper sheets, and rotation members; a transport roller; a second rotating member that limits the number of paper sheets that are fed onwards, and also has disc-shaped claw members with sharp portions for feeding the paper sheets, and rotation members; and a pressure roller that presses against the second rotating member to thereby grip and feed the paper sheets.

Abstract: A transfer drum for conveying a sheet in a machine of the graphic arts industry. The transfer drum is developed for controlling grippers without much effort and without much wear to the components of the gearing mechanism. The transfer drum includes grippers that are suited for holding an edge of the sheet and are arranged on a gripper shaft. Levers are fixed to the ends of the shafts. A cam mechanism for opening and closing the grippers has control cams that are connected to the frame and have contact surfaces, and cam followers fixed to the levers and in contact with the contact surfaces. Opposing torques act on the ends of the gripper shaft.

Abstract: Sheets are conveyed through a printing machine with improved reliability of the suction grippers. The apparatus for conveying a sheet through a printing machine has a cylinder with grippers in a channel for holding the sheet at its leading edge, circulating grippers for holding and for transferring the sheet from the cylinder at its leading edge, and circulating, radially positionable suction grippers for holding the sheet at its trailing edge. An actuating apparatus opens and closes the grippers and controls vacuum for the suction grippers. A drive for the cylinder and circulating grippers and suction grippers. A control device switches on and off the sheet feed to the cylinder. The suction grippers can be moved in the radial direction into a rest position when the sheet feed is switched off.

Abstract: The invention relates to a turning device (1) for transporting and turning over sheets (2) of printing material in a printing machine, preferably an electrophotographic printing machine, said device comprising at least two belts (7, 8), which, in particular, consist essentially of a plastic material, each of said belts being deflected as closed loops over respectively at least two deflecting elements (22, 23) and being crossed in order to turn over the respective sheet by approximately 180 degrees about its axis pointing in transport direction, in which process said sheet is held by clamping and frictional engagement between abutting segments (7?, 8?) of the tensioned belt, whereby at least one of the belts (7, 8), preferably each belt, is configured in a non-elastic manner, specifically reinforced, and that, in order to tension this belt, a tensioning device is provided.

Abstract: A machine for processing a sheet of printing material contains a first chain conveyor having a first gripper bar for holding a leading edge of the sheet, and a second chain conveyor having a rear gripper bar for simultaneously holding a trailing end of the sheet. A processing device is assigned to the chain conveyors for processing the sheet. A distance changing device is provided for temporarily reducing a gripper distance between the two gripper bars and, consequently, producing a sheet sag required for the processing of the sheet carried out by the processing device. The distance changing device defines a first circulation path of the front gripper bar, determined by the first chain conveyor, and a second circulation path of the rear gripper bar, determined by the second chain conveyor, running locally differently from each other. The processing device can be, for example, a sheet smoother.

Abstract: The sheet conveying apparatus includes a first member configured to convey a sheet along a predetermined conveying path while holding the sheet, a second member configured to convey a sheet along the predetermined conveying path while holding the sheet, and a changing unit configured to change a first state in which the first member and the second member convey the same sheet along the predetermined conveying path and a second state in which the first member and the second member convey different sheets in the predetermined conveying path according to a length of a sheet along the predetermined conveying path.

Abstract: A transfer wheel removes flat products from one location, such as an overhead conveyor, spaces the products apart, reorients them and then transfers the products to a second conveyor or other location. The transfer wheel is eccentrically mounted within a circular frame. Grippers mounted on radially-moving spokes of the transfer wheel rotate as the wheel turns, to reorient the products, for example from vertical to horizontal, so they can be laid flat on the second conveyor. The eccentric mounting of the wheel causes the spokes to increase the spacing between adjacent products as the wheel turns, to prepare the products for later processing.

Abstract: A sheet conveying device, that can be included in an image forming apparatus, includes a first sheet conveying path, a second sheet conveying path, a third conveying path, and a belt-type sheet conveying unit. The first sheet conveying path has a curved portion, and feeds and conveys a sheet therethrough. The second sheet conveying path has a curved portion and different from the first sheet conveying path, and feeds and conveys the sheet therethrough. The third sheet conveying path is provided from a confluence of the first sheet conveying path and the second sheet conveying path. The belt-type sheet conveying unit is disposed on one side of the third sheet conveying path corresponding to an outer side of the curved portion of the first sheet conveying path and an inner side of the curved portion of the second sheet conveying path.

Abstract: A transporting mechanism includes a link chain and clamps which are attached to a chain link of the link chain and which are capable of gripping at least one printed product. At least two clamps are attached to each chain link of the link chain, wherein the clamps in the link chain are spaced apart from one another by equal spacings.

Abstract: A sheet conveying device which is capable of stably conveying a sheet, irrespective of the material of the sheet. A first conveying roller pair nips and conveys a sheet. A drive motor drives the first conveying roller pair. An encoder detects the rotational speed of the first conveying roller pair. A first nip pressure-adjusting unit controls the nip pressure of the first conveying roller pair, and a CPU controls the first nip pressure-adjusting unit according to a change in the rotational speed of the first conveying roller pair detected by the encoder during sheet conveyance.

Abstract: A device for conveying a sheet through a typographic or printing technology machine reliably transfers a sheet from a cylinder to a trailing-edge gripper system and includes a chain conveyor, grippers for holding and taking over the leading margin of the sheet from a cylinder and grippers fixed to endless chains for holding the trailing, rear margin of the sheet. When the grippers for the trailing margin pass the cylinder, the grippers are guided in a closed state along a path outside a revolution contour of a support surface and, having passed the cylinder, the grippers are guided in an open state along a path to a radial level of the rear margin held in auxiliary grippers.

Abstract: A transfer drum for conveying sheets includes a revolving drum body, gripper systems provided on the drum body for holding the sheet at a leading margin thereof, and at least two rigid carrier elements having a cylinder-shell shape and being adjustable relative to the drum body. The carrier elements are disposed so as to be translationally displaceable relative to the drum body.

Abstract: In an apparatus for adapting the pressing force of a control roller on a control can in a sheet-processing machine by a torsion spring, the apparatus either changes the effective spring length or the spring stiffness as a function of the rotational speed of the sheet-processing machine. The spring can be a torsion spring rod with an actuator setting the spring force by changing the prestress. A stiffening element can be connected to the torsion spring rod and set the spring force by changing the spring stiffness of the torsion spring rod.

Abstract: A gripper system for controlling the loading and unloading of sheets on a cylindrical sheet guide. The gripper system comprises one or more grippers, which are positioned at an outer edge of the cylindrical sheet guide. Each gripper is coupled to a cam follower. The gripper system further comprises a cam, which is configured for affecting the elevation of the gripper(s) by moving the cam follower(s), and a servomotor, which is adapted for steering the cam. A cam-gripper controller is provided for controlling the servomotor according to a current printing profile.

Abstract: A device is provided for transferring printed sheet material products including a gripper conveyor having a plurality of grippers for gripping a plurality of printed sheet material products, a sheet conveyor for receiving the plurality of products from the plurality of grippers in a lapped stream, and a plurality of fingers, each finger assigned to one of the plurality of grippers, each finger contacting a first side of one of the plurality of products when a second side of the plurality of products is in contact with the sheet conveyor. A method is also provided.

Abstract: Sheets are conveyed through a rotary press with linear travel grippers. The novel conveying apparatus prevents collisions between the grippers and printing unit cylinders. The grippers are fixed to circulating links to convey a sheet through a nip between two cylinders that interact during printing. The links and the cylinders are coupled to drives that can be activated separately. In each case a collision disk is mounted on a shaft journal of at least one cylinder. A slip clutch is provided between the collision disk and the cylinder. A braking element is coupled to the grippers which, in the event of non-synchronous running with the cylinder, runs onto the collision disk and prevents the collision disk from moving.

Abstract: An apparatus for opening and closing a gripper, in particular a tongs-type gripper in a sheet processing machine, includes a radial cam for controlling a pivoting movement and an axial cam for controlling opening and closing movements of the gripper independently thereof, during a turning operation. A sheet-fed printing press having the apparatus is also provided.

Abstract: A sheet convey apparatus for a sheet-fed offset rotary printing press with a convertible mechanism includes a gripper device and a gripper pad shaft. The gripper device swings between a first position to receive a sheet from a chucking cylinder on an upstream side in a sheet convey direction and a second position to transfer the sheet to a gripper device on a downstream side in the sheet convey direction. The gripper pad shaft extends in a widthwise direction of the sheet and pivots together with the gripper device. A position of a rotating shaft axis at an intermediate portion of the gripper pad shaft is set within a range of an angle which is formed by a line that connects rotating shaft axes at two ends of the gripper pad shaft and a sheet holding position of the gripper device at the first position and a line that connects the rotating shaft axes at the two ends of the gripper pad shaft and a sheet holding position of the gripper device at the second position.

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: The invention relates to a device for maintaining an edge of a print media against a printing drum, said drum comprising a surface on which a print media is wrapped for printing thereon, wherein said device comprises at least one holder which comprises an abutment portion against which an edge of the media abuts before or during wrapping of the media on the drum surface, the holder being adapted to bring an upstanding portion of the media into contact with the drum surface by performing a movement with respect to the drum surface between a media edge reception position and a media edge clamping position, the movement of the holder from said reception position to said clamping position being performed in such a way that as the holder approaches the clamping position the distance between the edge of the media and the abutment portion of the holder increases, or remains substantially the same, thereby allowing the media in its clamping position to be substantially flat on the drum surface.

Abstract: An elastic sheet (5) comprises a first sheet (10) plated a metal film (11) on an upper surface thereof, a number of moveable contacts (20) attached on a lower surface of the first sheet (10), a second sheet (30) affixed on the lower surface of the first sheet (10) and defining a number of receptacle holes (31) corresponding to the moveable contacts (20). The second sheet (30) extends curved an extending portion (5) from a lateral side thereof and defines a recess (5) in the extending portion (5) thereof. A switch comprises the elastic sheet (5) and a circuit board (6). When the moveable contacts (20) engage with the fixed contacts, the elastic sheet (5) is affixed on the circuit board (6) by the adhesive on the second sheet (5), and then the first extending portion (5) connects to the circuit board (6) for contacting a ground end thereof.

Abstract: A signature hopper is provided comprising a first drum having a first gripper for a lead edge of a folded signature, a second drum having a second gripper for an open edge of the folded signature, the second gripper having a gripper finger with an end curled in a direction of rotation of the second drum, a dipper blade for pushing the open edge from the first drum toward the second drum so as to contact the gripper finger and a stationary signature guide spaced with respect to the first drum, the signature contacting the signature guide as the first drum rotates the signature past the signature guide.

Abstract: A sheet-processing machine, such as a rotary press, has normally closed grippers that circulate during operation. The grippers transport the sheets along a conveying section and guide the sheets at their leading and trailing edges. The conveying section is assigned a sheet decurler and a sheet guide device that follows the latter in the conveying direction. The conveying section further has a gripper opener assigned thereto for opening the trailing edge grippers carrying the trailing edges of the sheets in order to decurl the sheets. After the sheets have traversed the decurler and decurling has been carried out, the trailing edges are once more grasped with the trailing edge grippers for renewed positive guidance.

Abstract: A clamping device, a cylinder including a clamping device, and a method for clamping a plate onto the outer surface of the cylinder. The clamping device includes a base body extending in the axial direction and fixed to, or incorporated into the cylinder. The clamping device also includes a clamping element extending in the axial direction. The clamping device also includes a lifting bar located in the interior of the base body and coupled to the clamping element by at least one guiding shaft. The lifting bar being movable in a first radial direction to move the clamping element away from the outer surface of the cylinder to form a gap between the outer surface and the clamping element. The lifting bar also is movable in the radial direction opposite the first radial direction to close the gap formed between the outer surface of the cylinder and the clamping element.

Abstract: A machine for processing sheets of printing material has a cylinder for transporting the sheets and sheet supports which are mounted such that they can be rotated about a sheet support axis of rotation and in each case contain supporting segments for pressing the sheets onto the cylinder. The supporting segments are mounted such that they can be pivoted as desired into an active position and into a passive position about pivot axes that are skewed relative to the sheet support axis of rotation or about rotary joints determining the pivot axes.