Abstract: An apparatus for carrying or guiding a printing material sheet on an air cushion between a nozzle surface and the printing material sheet. The apparatus has first nozzle pairs which are arranged in a first row and second nozzle pairs which are arranged in a second row for generating the air cushion. The first nozzle pairs and the second nozzle pairs in each case have a blower nozzle and a suction nozzle, which are paired in such a way that one and the same air flow is blown out by the respective blower nozzle and is aspirated, at least predominantly, by the suction nozzle that is paired with the blower nozzle. The suction nozzles of the first nozzle pairs are arranged in such a way between the blower nozzles of the second nozzle pairs and the suction nozzles of the second nozzle pairs such that the air flows of the second nozzle pairs flow past the suction nozzles of the first nozzle pairs.

Abstract: In a method of operating a machine processing printing material sheets and having a sheet transport drum in various operating modes, drum circumferential shells are kept fixed on the sheet transport drum in an outer position in a first of the operating modes and in an inner position in a second of the operating modes. During a drum conversion to be carried out before the start of a third of the operating modes, the drum circumferential shells are removed from the sheet transport drum and, in this third operating mode, the sheet transport drum is rotated without the drum circumferential shells.

Abstract: A sheet transfer device for a sheet-fed rotary printing press includes a registration correction device. The registration correction device deforms the leading edge of the sheet using a deformable gripper bridge system. The gripper bridge system includes a gripper bridge which extends continuously over the width of the sheet transport path. The gripper bridge is supported at each of its two ends by a pivotable support to allow the gripper bridge to assume a deformed shape similar to that of a simply-supported beam.

Abstract: A cam device includes an armlike cam follower for moving a lift unit upward and downward, and a plate cam having a cam contour face in contact with the cam follower. The cam is formed in a side surface thereof with a recessed portion having an inwardly facing periphery which provides a guide face extending along the cam contour face. A movable roller is in bearing contact with the guide face. The cam follower and the movable roller are biased toward each other by and elastic member.

Abstract: A sheet turning device including a turning drum for turning over stock or a print carrier received in an ideal path of motion from a storage drum in a recto/verso or first-form and perfector printing process is in combination with a sheet-metal guide having a surface member formed with air outlet openings for floatingly guiding the stock or the print carrier, the surface member being disposed so as to face a printed side of the stock or the print carrier below the turning drum and extending in a direction towards the storage drum.

Abstract: A folding cylinder for a web-fed rotary printing press is provided with signature end engaging point spurs. The cylinder is also provided with signature grippers which will engage the signature end or sides so that the point spurs can be retracted at a slower rate of speed to thereby avoid damaging the signature end.

Abstract: A rotary printing press for printing on sheets of printing stock will typically have cylinders mounted therein for transporting the sheets of printing stock through the printing press. Such transfer cylinders can typically be equipped with a gripper device for engaging the sheets of printing stock, which gripper device can be formed be a plurality of individual gripping fingers pivot-mounted to the cylinder, with each gripping finger being operated directly and substantially separately from the other gripping fingers.

Abstract: A cylinder for a rotary printing press is provided with a press blanket clamping device that is usable to secure the ends of the press blanket to the cylinder. A blanket end ejection device is used to dislodge an edge strip of a blanket leading edge from an edge strip receiving groove portion of the clamping device. The ejection device uses one or more ejection pins and cooperating leaf springs to position the edge strip during its insertion and ejection into and from the press blanket clamping device.

Abstract: A lock-up assembly (20) for securing a printing plate (22) on a plate cylinder (10) includes a rotatable lock bar (32) and a spring biased linkage mechanism (36). The linkage mechanism (36) has a first over-center condition in which it rotates the lock bar (32) toward a locked position, and has a second over-center condition in which it rotates the lock bar (32) toward an unlocked position. A movable blocking member (82) blocks the linkage mechanism (36) from switching to the second over-center condition under the influence of centrifugal force when the cylinder (10) is rotating during a printing operation. A hand held tool (40) engages the linkage mechanism (36) to switch it between the first and second over-center conditions upon manual manipulation of the tool (40). The tool (40) also engages the blocking member (82) to move the blocking member (82) from the first position to the second position when the tool (40) is moved into engagement with the linkage mechanism ( 36).

Abstract: Swivelling pre-gripper of a sheet-fed printing press having a sheet feeding table includes a swivel arm; a gripper carried by the swivel arm; a mutually cooperating roller lever and cam mechanism for, respectively, opening and closing the gripper; a device for cyclically swivelling the swivel arm of the pre-gripper to and away from the sheet feeding table; a device for cyclically opening and closing the gripper; a device for setting an instant of opening of the gripper for releasing a sheet gripped by the gripper in a closed condition thereof to a downline conveying device for accepting and transporting the released sheet; a device for setting, in a manner decoupled from the setting of the instant of opening, an instant of closing the gripper for gripping the sheet fed from the feeding table to the pre-gripper; one of the devices for setting the instant of opening and for setting the instant of closing of the gripper being disposed on the roller lever; and the other of the devices for setting the instant of c

Abstract: A device for changing-over a gripper control on a gripper cylinder of a turning device in a sheet-fed rotary printing machine for first-form and perfector printing, including an adjusting gear and a fixed gear disposed coaxially with one another, the adjusting gear being adjustably movable so as to vary the angular position thereof relative to that of the fixed gear, and a clamping device for clamping the adjusting gear and the fixed gear frictionally together, comprising a control shaft axially displaceable in the gripper cylinder, the control shaft being rotatable and being coupled, via a first intermediate converting device, with the adjusting gear so that an adjustable movement of the adjusting gear is converted thereby into a rotary movement of the control shaft, a spring device for applying a reaction force to the control shaft in a clamping direction of the adjusting gear, an adjusting bridge carried by the gripper cylinder so as to be displaceable in axial direction thereof, an angle lever disposed in

Abstract: An arrangement on transfer drums for in-registry sheet transfer in sheet rotary printing machines, has gripper units mounted on cylinders, toothed segments which during a sheet transfer are in engagement, each of the gripper units having a gripper shaft, a gripper and a turnable gripper traverse which receives the gripper shaft and said gripper and fixedly connected with one of the turnable toothed segments, and an elastic element associated with the toothed segment.

Abstract: A sheet feeding unit for a rotary sheet printing machine which is operative for selective face printing or face and back printing with turning of a sheet rear edge and which has a turning cylinder and a printing cylinder located before the turning cylinder, includes elements located underneath the turning drum and the printing drum for conducting and guiding overlong sheets in face and back printing during a turning step on a front edge. The elements include a suction member arranged rotatably over a circular path so as to take over a sheet in a point of intersection of tangent t.sub.s, a stationary segment arch arranged equidistantly relative to the circular path under a point of intersection T.sub.4,5 of the printing cylinder and a sheet guiding cylinder and also provided with guiding rollers, and a guiding plate located above a turning point of the suction member at a distance from the printing cylinder and inside the circular path over a line of a secante.

Abstract: A device for adjusting a rotational position between coaxial fixed and adjusting gears and for changing-over a gripper by axially displacing an adjusting member on a cylinder of a turning device of a sheet-fed rotary printing press, includes a pressure member for effecting a spring coupling of the gears via a radially extending pressure lever. An adjusting member which reduces the spring force is axially displaceably guidable on the cylinder and becomes effective upon the pressure member only after traversing a distance for actuating a switch of an electrical safety device in a power supply circuit of a driving device. Another electrical safety device is between control positions of the adjusting member for interrupting the supply circuit to change over the gripper control.

Abstract: A sheet reversing unit for a sheet printing press which includes a reversing gripper device and a suction lever. A cam follower is pivotally mounted on a cam lever and is brought into contact with a cam surface of a cam mechanism for opening and closing the sheet gripper. A regulating cam is arranged outside the moving path of the cam follower, so as to prevent the cam follower from falling outside its normal moving path.

Abstract: A sheet clamping system for high speed rotatable drums is provided in which light-weight clamping bars, formed of relatively thin metal sheet stock, are configured and/or oriented for maximum resistance to deflection radially of the axis of drum rotation as well as positively secured in a sheet medium clamping position at axially spaced intervals along the length of the drum. The system further includes centrifugally actuated, axially extending rods positioned to underlie the operative portion of each clamping bar in a manner such that leading and trailing edges of a retained sheet are sandwiched between the rods and the clamping bars under a clamping force generally proportional to the square of drum rotational speeds.

Abstract: A conveyor for a sheet-fed rotary printing press for transferring sheets away from an impression cylinder includes a delivery cylinder disposed adjacent the impression cylinder, and a chain conveyor having a plurality of sheet grippers, adapted for moving the grippers about the delivery cylinder for successively engaging sheets on the impression cylinder. The delivery cylinder has a gap in its outer periphery for receiving successive of the sheet grippers during transfer of a sheet from the impression cylinder to the sheet grippers. The sheet grippers each include a support and a pivotable gripper finger, and a displacer mounted on and extending rearwardly of each gripper support for bridging the gap in the delivery cylinder within which the gripper is disposed during a sheet transfer operation, and for maintaining tension in the sheet during transfer from the impression cylinder to the chain conveyor. The displacer is comb shaped having a plurality of rearwardly extending arcute shaped teeth.

Abstract: Transmission system for forming cyclical motion from rotational motion including a device having a rotating part and at least one control lever set into cyclical motion by rotational motion of the rotating part, the one control lever and the rotating part being in cooperative engagement whereby a varying force is applied to the control lever producing a torque fluctuation in the rotational motion, includes another device for producing cyclical motion, the other device being in operative engagement with the rotating part, and spring means for applying a force to the rotating part so as to compensate for the torque fluctuation.

Abstract: A sheet-turning drum in a sheet-fed rotary printing press for optionally first printing or perfecting printing is provided that is simple to assemble and adapted to be changed over for differing printing requirements. To this end, the sheet-turning drum is subdivided into a unitary main member and a cylindrical drum envelope. The latter having a sheet support surface and flanges disposed on its end faces for securing the envelope between mounting flanges on the main member. The sheet support surfaces of the drum envelope can be in the form of a smooth metal surface, an ink-repellent fabric or support rollers retained on carrying rods.

Abstract: A reversing gripper apparatus of a one side/perfecting printing press is disclosed. This reversing gripper apparatus comprises a receiving portion wherein a gripper pad fixed to the external circumference of a reversing cylinder grips a sheet of paper in combination with gripper members and a space for withdrawal, the gripper members comprise a combination of a master gripper provided on a common shaft and an auxiliary gripper opposed to the master gripper, the master gripper is formed with a width sufficient to cover the receiving portion of the gripper pad and the point of the auxiliary gripper at the same time and is controlled by a common shaft, and the auxiliary gripper has such a width as to be partly opposed to the width of the master gripper and is controlled with the common shaft as the center. By adopting this structure, the gripping function, register accuracy, and the gripping force of the reversing gripper apparatus are greatly increased.

Abstract: A vertically adjustable gripper support mechanism for the grippers of turning drums of perfecting presses wherein the sheet is turned by two correlatively cooperating gripper systems disposed on cam-controlled pivot shafts biased by return springs. An adjusting shaft is disposed concentrically within the pivot shaft and is rotatable by an adjusting wheel, the adjusting shaft being formed with axially spaced recesses corresponding to the number of gripper supports and having a plurality of arcuate adjusting surfaces preferably offset at 60.degree. in the peripheral direction to one another to provide a multistep vertical adjustment to the gripper support.

Abstract: In sheet-fed rotary printing machines, a sheet transfer cylinder having a sheet-bearing cylinder jacket formed of a plurality of jacket segments arranged next to one another in circumferential direction of the cylinder, the jacket segments extending at least over a sheet-bearing circumferential area of the sheet transfer cylinder, includes locking elements located at respective ends of the jacket segments and engaging in corresponding receiving elements on end surfaces of the cylinder, the locking elements being a pair of guide cams located at each end of the jacket segments, and the receiving elements being receiving grooves formed concentrically in a support disc defining an end surface of the cylinder, the guide cams being guided in circumferential direction of the cylinder and lockable in the receiving grooves.

Abstract: A sheet diverter system in which a stream of sheets is fed by a pair of tapes to a gripping zone between a pair of separating cylinders. The tapes on opposite sides of the sheet diverge downstream of the gripping zone and wrap around a part of the outer periphery of the adjacent separating cylinder so that they travel at the same velocity as the outer periphery of the cylinder. The sheets advance toward the gripping zone at a velocity controlled by the separating cylinder and successive sheets are presented to the grippers carried by the cylinders so that alternate sheets are carried along different paths to different delivery stations.

Abstract: Sheet transfer cylinder assembly of a sheet-fed rotary printing machine including a sheet transfer cylinder and a device for correcting register of overprints on a sheet by deforming the leading edge of the sheet which includes a gripper fly supported on a shaft and swingably mounted on the sheet transfer cylinder, and a bending device carried by the sheet transfer cylinder in a middle region thereof, the bending device being cooperatively associated with the gripper fly and being actuatable by swinging movement of the gripper fly for flexing the shaft of the gripper fly and deforming the leading edge of the sheet in a direction tangential to the circumference of the cylinder.

Abstract: In a duplicating machine for duplicating images on both sides of copy sheets including a blanket cylinder and an impression cylinder, a mechanism for handling the sheets and re-feeding the sheets back to the impression cylinder for duplex copying. The blanket cylinder has first and second images transferable to the copy sheets. The impression cylinder forms a nip with the blanket cylinder for transferring the copy sheets through the nip. A first gripper on the impression cylinder releasably engages a lead end of a copy sheet and moves the sheet through the nip to transfer the first image on a first side of the sheet. A chain gripper releasably engages the lead end of the sheet transferred thereto by the first gripper and transports the sheet away from the impression cylinder. A swing gripper releasably engages a trail end of the sheet in timed relation with release of the sheet by the chain gripper and re-feeds the sheet back to the impression cylinder.

Abstract: A sheet clamping device is provided which is used to clamp both the leading and the trailing end of a sheet while the sheet is being disposed around the peripheral surface of a drum rotating in a given direction. The drum is provided with a front and a rear claw which are adapted to clamp the leading and the trailing end of the sheet, respectively, and which are urged to bear against the peripheral surface of the drum. The claws are operated to open or close in response to respective claw operating means. After a sheet has its leading end clamped to the drum surface by means of the front claw, combing urges the sheet against the drum surface while combing it, and the trailing end of the sheet is clamped to the drum by means of the rear claw.

Abstract: The sheet fed rotary press includes a feed cylinder cooperating with a feed table extending in a plane situated below and in spaced relationship from the periphery of the feed cylinder. An auxiliary gripper system located under the feed cylinder provides for the transfer of respective sheets from the feed table to the feed cylinder.

Abstract: An adjusting device for sheet reversing in a sheet-fed rotary press comprises a reversing cylinder which is driven by a drive shaft and carries a plurality of sheet grippers, a rotary drum carrying a plurality of leading-end grippers, a rotary assembly carrying a plurality of trailing-end grippers, which is concentric with said drum, a flange fixed to said drive shaft, a first drive gear fixed to said flange, a second drive gear which is adjustably attached to said flange and has a driving connection with said rotary assembly, a third drive gear which is adjustably attached to said flange and has a driving connection with said rotary drum, and means for manually rotating said reversing drive cylinder through said first gear, for selectively adjusting the angular position of attachment of the second and third gears to said flange.

Abstract: A sheet drawing device for a sheet-fed rotary press comprises a pair of adjusting gears adjustably mounted on a main shaft, a plurality of segment arms rotatably mounted on the main shaft, a bearing block adjustably mounted on each of the segment arms, which is pivotably mounted for adjustment about an axis perpendicular to the bearing axis of the bearing block, a sheet-drawing roll journaled in each bearing block, a plurality of fixtures secured to a gripper shaft which is pivotably mounted in the adjusting gears, each fixture being resiliently connected to a guide which is rotatably mounted on the gripper shaft and which carries a freely rotatable trailing-end gripping roller that is engageable with one of the sheet-drawing rolls, means for controlling pivoting of the gripper shaft to bring the trailing-end gripping rollers into and out of sheet gripping engagement with the sheet-drawing rolls, a second gripper shaft pivotably mounted in the adjusting gears, on which are secured a plurality of driving arms

Abstract: Each of both clamping jaws of a product gripper are formed by a holder portion and an extension portion formed of one-piece with the related holder portion. Both of the holder portions are held in their closed position by means of a closure spring. The clamping jaws are conjointly pivotable about a shaft which simultaneously serves as the pivot shaft for the hinge connection between both of the clamping jaws. If the product gripper is rocked into a product receiving position, then the extension portion of one clamping jaw is located at one side of a stop in contact therewith. For opening the gripper there is exerted an opening force upon the extension portion of the other clamping jaw, so that the related holder portion is raised from the other holder portion against the force of the closure spring. For releasing the seized product the clamping jaws are rocked in clockwise direction into their product release position where the extension portion of the other clamping jaw bears against the stop.

Abstract: A system for duplicating images on copy sheets utilizing an impression cylinder. The system provides for transfer of an image to one side of each sheet, and the sheet may then be reversed to locate the sheet on the impression cylinder, trailing edge first. The reversing is in synchronism with a second image whereby this second image may be transferred to the opposite side of each sheet. The impression cylinder is provided with a first gripper for engaging the leading edge of each sheet when the sheet is first fed to the impression cylinder. A second gripper is provided on the impression cylinder for engaging the trailing edge of each sheet, and this second gripper turns around to achieve the reversing action after application of the first image. The first gripper is externally mounted and is movable relative to the impression cylinder whereby the relative positions of the grippers can be changed so that different size sheets can be duplexed.

Abstract: The basic press structure includes a printing couple consisting of a lower printing cylinder, having a single work area, and a large printing cylinder, having an effective diameter which is a whole multiple, greater than one, of the effective diameter of the lower printing cylinder, and has a number (equal to the whole multiple) of work areas, in each of which one of a variety of the especially constructed removable and interchangeable segments may be mounted. One of a variety of different printing surfaces may be carried in each of the various work areas on the cylinders of the printing couple, in a wide range of combinations. The printing couple is mounted in a frame structure constructed so as to provide a plurality of module mounting positions, at each of which one of a variety of printing modules may be mounted in cooperative relationship with the large printing cylinder.

Abstract: A sheet advancing cylinder in an offset printing machine, has a sheet gripping system arranged in its interior. The system includes a rocking member rigidly connected to a first gripper for moving the latter between two terminal positions in a slot formed in the jacket of the cylinder. The movement of the rocking member is such that in the first terminal position the first gripper is flush with the jacket periphery, in an intermediate position it is above the periphery and in the second terminal position it is below the periphery.

Abstract: A system for duplicating images wherein a copy sheet is delivered to a first gripper of an impression cylinder. A first image is transferred to one side of each sheet, and each sheet is then released by the first gripper and delivered to a reversing means. A second gripper includes means for engaging the trailing edge of each sheet and the sheets are thus re-fed to the impression cylinder by this second gripper, trailing edge first. The re-feeding is in synchronism with the second image whereby this second image is transferred to the opposite side of each sheet. The second gripper is provided with inverting means to accommodate the re-feeding. In addition, separate gripper means are provided on the second gripper for engaging the trailing edge of a succeeding sheet whereby the second gripper simultaneously engages the trailing edge of one sheet and the formerly trailing edge of a previously introduced sheet.

Abstract: A gripper mechanism for seizing the trailing edges of paper sheets on a transfer drum of a printing machine. A plurality of rollers are resiliently mounted so as to be rotationally shiftable toward the direction of movement of the paper sheet. The rollers are oriented at various oblique angles with respect to the movement direction, with rollers further from the middle axis of the transfer drum being oriented at a greater oblique angle than rollers closer to said axis.

Abstract: In a printing press having a conventional plate cylinder and an impression cylinder operatively positioned on a frame with the impression cylinder having gripper fingers and a gripper finger positioning shaft, the improvement relating to a tumbler member secured to one end of the gripper finger shaft and having pin receiving recess means formed in such tumbler member. A pair of fluid-actuated independently controlled cylinders are provided at the end of the impression cylinder whereby when the cylinders are actuated the piston rods extend therefrom for engagement with the tumbler member to turn it and its associated shaft through an arc by rotation of the impression cylinder for controlling the operative and inoperative positioning of the gripper fingers on the gripper finger shaft.

Abstract: In a printing mechanism, the leading edge of a sheet of paper is fed onto the printing surface of a cylindrical drum and is clamped thereto. A gear is rotatively attached to the drum, and a sensor controlled gear segment clutch, which is mounted for rotation independently of the drum, controls the clamping and rotational movement of a clamp for clamping the trailing edge of the sheet of paper. The sensor senses when the trailing edge of the sheet passes thereby and activates the gear segment clutch which rotates toward the gear attached to the drum and engages it. The rotational movement of the gear segment clutch results in the closing of the trailing edge clamp onto the trailing end of the sheet of paper. The gear attached to the drum rotates the gear segment clutch and it in turn rotates the trailing edge paper clamp which now rotates the drum. Consequently, the above described printing mechanism can clamp both ends of variable length paper onto a cylinder and rotate it for a print operation.