Sheet-processing machine with a sheet guide cylinder and a delivery unit, and method for operating a sheet-processing machine.

Abstract

Sheet processing machine with a sheet guide cylinder (3) and a delivery, wherein a first drive wheel for driving the arc guide cylinder (3) is assigned to the end face of the arc guide cylinder (3) and wherein the delivery system has a front edge gripper system (4) and a rear edge gripper system (5) for transporting sheets at the front edge and rear edge, characterized by that a further second drive wheel is assigned to the arc guide cylinder (3) and that the two drive wheels assigned to the arc guide cylinder (3) are arranged coaxially to each other.

Description

[0001] The invention relates to a sheet processing machine with a sheet guiding cylinder and a delivery according to the preamble of the first claim and to a method for operating a sheet processing machine.

[0002] DE 42 18 421 A1 discloses a sheet guide in the delivery of a printing press in which the gripper system for the leading edges of sheets can be driven by the transfer cylinder, and the gripper system for the trailing edges can also be driven by the transfer cylinder via an intermediate gear. The disadvantage of this solution is that it requires a lot of installation space. Changing the format requires a relatively high level of additional effort.

[0003] DE 10 2011 011 396 A1 shows a device for feeding sheets to a stack of sheets, wherein a switchable clutch for adjusting a distance between holding devices is arranged on a sprocket drive shaft and a further clutch is arranged on a sprocket deflection shaft.

[0004] The invention is therefore based on the object of further improving the sheet transport in the delivery of a sheet processing machine.

[0005] According to the invention, this object is achieved by a device having the features of the independent device claim and a method having the features of the independent method claim. Advantageous embodiments emerge from the subclaims, the description, and the drawings.

[0006] The invention has the advantage that the sheet transport in the delivery of a sheet processing machine is further improved.

[0007] Advantageously, preferred embodiments provide a simple, robust solution that does not require failure-prone gears such as superposition gears, etc.

[0008] In a preferred embodiment of the invention, the format adjustment is carried out by a pair of drive wheels, in particular a pair of gears, assigned to the last sheet-guiding cylinder. One of the gears drives the leading edge gripper system, and the other gear drives the trailing edge gripper system in the delivery. These gears, which can be rotated relative to one another, enable simple drive and interference-free format adjustment of the gripper systems in the delivery.

[0009] In a further development of the invention, the sheet transfer system arranged upstream of the sheet guide cylinder is optionally designed as a sheet transport drum with enclosed surfaces, as a transfer drum without enclosed surfaces, or as a transfer drum with axially adjustable sheet support segments. Depending on the machine design, for example, if the last unit is designed as a printing unit or a coating unit, or if the machine includes a perfecting device, the appropriate sheet transfer system can be installed or retrofitted at the otherwise unchanged location. This modularity reduces costs and increases flexibility.

[0010] In a preferred development of the invention, the sheet transfer system upstream of the sheet guiding cylinder is designed as a sheet transport drum with axially adjustable suction discs and a trailing edge guide element for the sheet trailing edges that can be adjusted to the format length. The trailing edge guide element rotating with the suction discs can be a suction gripper or a pressure element. Suction grippers can be used to fix the sheet trailing edges throughout the entire cycle, while the pressure elements or guide plates advantageously press protruding rigid sheet trailing edges during sheet transfer to the downstream sheet guiding cylinder. Particularly preferably, this trailing edge guide element is driven by a drive wheel of the sheet guiding cylinder and, together with the trailing edge gripper system, is adjusted to the sheet length in the delivery.The combined format adjustment is particularly advantageously achieved by rotating the gears of the sheet guide cylinder relative to each other. This eliminates the need for a separate drive for the trailing edge guide element.

[0011] In further developments of the invention, the gripper systems, which are driven continuously by traction means, are designed as chain-driven gripper carriages in the delivery. Leading edge gripper carriages are driven by a first sprocket main shaft, and trailing edge gripper carriages are driven by a second sprocket main shaft. The sprocket main shafts can be arranged concentrically or eccentrically offset from one another. In a preferred development, the sprocket main shafts are arranged eccentrically to one another, which enables a simpler construction of the individual sprocket main shafts. Particular preference is given to using sprocket main shafts that are eccentrically offset from one another and rotate in the same direction.

[0012] In a further development, the sheet guiding cylinder is designed as a storage drum with a base body that is fixed to the preceding gear train of the main drive and a format-adjustable part. On the drive side of the machine, this storage drum has two coaxially arranged gears. The first gear is fixedly connected to the base body of the storage drum and is driven via the gear train. This first gear also drives a first sprocket main shaft in the delivery, which preferably drives the gripper systems that grasp the leading edges of the sheets. Suitable intermediate gears or intermediate gears and traction drives can be used to bridge the distances. The second gear is fixedly connected to the format-adjustable part of the storage drum and can be rotated relative to the first gear. Both gears are connected to one another via a coupling. The second gear is preferably, for example,It is attached to the axle knuckle of the storage drum via a hydraulically expandable press fit. This second gear drives, again via suitable intermediate drives, a second sprocket main shaft in the delivery, which drives the gripper systems that grasp the trailing edges of the sheets.

[0013] In this case, the first gear is advantageously connected to front casing segments and the second gear is connected to the rear casing segments of the storage drum. The rear casing segments are adjusted to the sheet format when the second gear is rotated relative to the first gear, forming a comb-like, intermeshing sheet support surface. In this case, the drive for the gripper systems of the trailing edge gripper system can advantageously be tapped for the correct format at the same time from the second gear. This accelerates and simplifies format setting movements on the machine. Advantageously, in this development, when the format length on the storage drum changes, the position of the sprocket main shaft for the trailing edge gripper system is automatically adjusted as well, since this sprocket main shaft is driven, for example, via intermediate gears from the format-adjusted second gear of the storage drum.

[0014] A particularly advantageous way to adjust the format on straight-printing presses is to brake the trailing edge gripper system, in particular the main sprocket shaft of the trailing edge gripper system, release the gear connection on the sheet guide cylinder via a clutch, e.g., by hydraulically expanding the interference fit between the gears, and then rotate the front part of the press, which involves simultaneously adjusting the main sprocket shaft of the leading edge gripper system in the delivery to a new position. In this new position, the gear connection on the sheet guide cylinder is established by engaging the gears, e.g., via the interference fit.

[0015] In perfecting presses, there is at least one additional clutch in the gear train. A first clutch is located in the perfecting device, in particular on the storage drum of the perfecting device. The other clutch is assigned to the sheet guiding cylinder located in the delivery. It is particularly preferred on these machines that format adjustments are not carried out sequentially, but simultaneously. This brakes the main sprocket shaft of the trailing edge gripper system and the perfecting section of the press. The middle section of the perfecting press, i.e. the entire gear train between the coupling points, is moved to a new position via an auxiliary drive. Both clutches are then closed again.The entire format adjustment on perfecting presses is thus performed simultaneously by simply turning the center section of the gear train, which adjusts both the perfecting units and all gripper systems to the sheet length. As an additional feature, a trailing edge guide element of the sheet transfer system located upstream of the sheet guide cylinder can also be adjusted to the format length simultaneously.

[0016] The invention will be explained below by way of example. The accompanying drawings illustrate this schematically: Fig. 1: Perspective view of a section of a sheet-fed printing press with delivery from the drive side; Fig. 2: Schematic of the drive of the sprocket main shafts in the delivery in a side view from the drive side.

[0017] The Fig. 1 shows, in one embodiment of the invention, a section of a delivery of a sheet-processing machine, in this case a sheet-fed printing press. The printing press can, for example, be a sheet-fed offset rotary printing press in unit or in-line design and contain elements not shown in detail, such as a feeder, infeed, several printing and, if applicable, coating units, finishing and / or drying units. In the machine, sheets to be printed are conveyed by cylinders and transferred between the cylinders in a gripper lock. The sheets are thus clamped at the leading edge and transported to the delivery. In the delivery, the sheets are taken over by conveyor systems with continuously rotating gripper systems and, fixed at the leading and trailing edges, are conveyed to a pile support plate (not shown in detail). The sheets are released above the pile support plate to form a delivery pile.The stack support plate is lowered vertically by a lifting drive depending on the incoming sheets.

[0018] The printing press is preferably of modular construction, with a penultimate substructure module of the press, shown here, comprising a printing cylinder 1 and a sheet transfer system arranged downstream of it. The printing cylinder 1 has an almost closed outer surface. After the printing cylinder 1 of the last printing or coating unit, the sheets are transferred from the sheet transfer system to a downstream sheet guiding cylinder 3. The sheet transfer system can be a component known from printing units, around which the sheets are guided with the aid of guide plates and / or drum caps.

[0019] The sheet transfer system can be a cylinder with a closed outer surface or a transfer drum 2 with air guidance as shown here, or it can also have sheet support segments or discs. Under certain circumstances (e.g. if the last unit is a coating unit), it may be necessary to guide the sheet around the area of ​​the aforementioned sheet transfer system with the help of (at least two) suction discs. These suction discs have a small axial extension and preferably consist of suction segments that can be switched on and off depending on the angular position (e.g. via a rotary valve). The discs are preferably placed on the non-printing side edge of the sheet. When removed from the last printing cylinder 1, the sheet is grasped at the leading edge by known grippers of the sheet transfer system, wound onto the aforementioned discs, and securely guided by their suction effect.In addition to the suction discs mentioned, the use of additional suction and / or support elements is conceivable, which can be adjusted as required.

[0020] The sheet guiding cylinder 3, located downstream of the transfer drum 2, is mounted in a final substructure module of the machine. The rotational axis of the sheet guiding cylinder 3 can be in the same plane as the rotational axes of cylinders in the machine's units or can be arranged above such a plane. All rotating sheet conveying systems shown here are designed as double-sized cylinders. For sheet transport, these double-sized systems each contain two diametrically arranged gripper systems located in gripper channels for securing the leading edges of the sheets. Alternatively, the sheet conveying systems can also be designed as drums, transferters, or similar devices and can be single- or multiple-sized, whereby a single-sized cylinder can accommodate at least one sheet of the maximum format circumferentially.In a further development of the invention not shown, it is provided that the outer surface of the sheet guiding cylinder 3 is designed in the middle as a largely continuous ring which serves as a counter surface for a cutting device.

[0021] In a further development of the invention (not shown), the sheet guiding cylinder 3 is designed as a storage drum upstream of the traction-driven gripper systems in the delivery. This storage drum consists of grippers for gripping the leading edge of the sheet and a row or individual suction cups for gripping and tightening the trailing edge of the sheet. By sliding the comb-like storage drum segments into one another, the distance between the grippers and the row of suction cups can be adjusted to the respective sheet length. The row of suction cups is located in a channel and is positioned on the pressure-free trailing edge of the sheet. The row of suction cups has expediently selected gaps to allow the trailing edge of the sheet to be removed from the storage drum using grippers. To tighten the sheet, the suction cups can be moved in the circumferential and axial directions.Since the tightening movement results in a relative movement between the underside of the sheet and the outer surface of the storage drum, it is recommended that the tightening movement be carried out only shortly before the respective trailing edge of the sheet is transferred to a continuously rotating gripper system of the delivery, since at this moment the sheet is already largely detached from the storage drum and hangs freely in space. The contact between the storage drum and the sheet at the moment of tightening can be further reduced or even eliminated by appropriately installed suction fans, blower pipes or similar devices that deflect the sheet upwards. To prevent ink smearing, the sheet guide cylinder 3 or the storage drum can be covered with an ink-repellent cloth or film, which can be unwound from a suitable winding device and pulled onto the outer surface of the sheet guide cylinder 3 or the storage drum that is to be covered.Alternatively, the gaps can be covered with so-called strip jackets.

[0022] In further developments not shown, additional devices can be assigned to the sheet guiding cylinder 3. Examples of additional devices include inspection systems, powder devices, inkjet and other marking systems, embossing and ionizing devices, counting devices, numbering devices, cold foil devices, and dryers. As a further development, the attachment location for the additional devices on the sheet guiding cylinder 3 is designed as a standardized interface to which interchangeable modules with the desired functions can be attached as needed. Furthermore, the attachment location can be designed so that additional devices can be combined in a type of turret changer and, as needed, brought into the desired position at the active point by moving, in particular by rotating, the changer. This attachment location is also suitable for ejecting sheets individually or in large numbers.This can affect, for example, sample sheets or waste sheets, but can also be used to deliberately create a sheet gap to better retract a non-stop roller blind into the delivery stack. A further development is planned to design the sheet guiding cylinder 3 in such a way that the grippers do not protrude beyond its outer surface when closed. This allows the aforementioned additional devices to be moved very close to the printing substrate.

[0023] The delivery shown here contains a first conveyor system arranged downstream of the sheet guiding cylinder 3 in the sheet travel direction BLR, with circumferentially guided gripper systems for sheet leading edges, and a second conveyor system with circumferentially guided gripper systems for sheet trailing edges for receiving and conveying the sheets from the sheet guiding cylinder 3 to a sheet stack (not shown in detail). The first conveyor system with the circumferentially guided leading edge grippers is designed as a leading edge gripper system 4, preferably as a chain conveyor system with circumferentially guided leading edge gripper carriages. The second conveyor system with the circumferentially guided trailing edge grippers is designed as a trailing edge gripper system 5, preferably as a chain conveyor system with circumferentially guided trailing edge gripper carriages.

[0024] Both the first chain conveyor system with the rotating leading edge gripper carriages and the second chain conveyor system with the rotating trailing edge gripper carriages are arranged above a horizontal plane for transporting the sheets from the sheet guide cylinder 3 to the sheet stack, which plane is tangent to the upper surface line of the sheet guide cylinder 3. The sheet transport by the chain conveyor systems takes place exclusively on a horizontal sheet conveyor path from the sheet guide cylinder 3 to above the sheet stack. Additional devices (not shown) can be arranged on the sheet conveyor path to the sheet stack and act on the sheets during sheet transport. Dryers and powder devices can, if necessary, act on the printing substrate with strong air jets, since the sheet is held by the chain conveyor systems at the leading and trailing edges, thus severely limiting its ability to flutter.

[0025] The sheet guiding cylinder 3 has two drive wheels on the drive side of the machine, the first of which, located inside, drives the sheet guiding cylinder 3 rotationally and thus synchronizes the gripper systems for the sheet leading edges. The drive wheels are designed as gears of the central gear train driven by the main drive. The two gears are arranged coaxially to each other and coaxially to the sheet guiding cylinder 3 and can be detachably connected. Both gears are non-positively connected to one another by means of a coupling. The first gear is connected to the gear train of the straight-printing units of a straight-printing press or to the partial gear train of a perfecting press downstream of the perfecting unit. The first gear is also connected to the leading edge gripper system 4 in the delivery. The second gear is connected to the trailing edge gripper system 5 in the delivery.Here, both the drive and the format adjustment of the gripper systems are carried out via the gears of sheet guide cylinder 3. The connection between the gears and the gripper systems can be established using intermediate gears or other positive-locking drives, e.g., chains or toothed belts, or even a combination of gears. When adjusting the format, the coupling between the gears is released and both gears are rotated relative to each other. For this purpose, the front or rear part of the machine can be held in place with a brake, while the other part of the machine can be moved into the new position via the drive motor, thus implementing the format adjustment.

[0026] The leading edge gripper system 4 in the delivery contains laterally arranged chains wrapped around sprockets of a first sprocket main shaft 6, which drive the leading edge gripper carriages continuously on a circular path. Since the leading edge gripper carriages receive the leading sheet edges from the sheet guiding cylinder 3, they are always synchronized with the gripper systems of the sheet guiding cylinder 3. The trailing edge gripper system 5 in the delivery also contains laterally arranged chains wrapped around sprockets of a second sprocket main shaft 7, which drive the trailing edge gripper carriages continuously essentially, preferably exactly, on the circular path of the leading edge gripper carriages. Additional chain deflection guides (not shown) are arranged above the sheet stack. In the embodiment shown here, the sprocket main shafts 6, 7 (drive shafts) of the respective systems are arranged eccentrically to one another in order to achieve a simple structure of the shaft, bearings, and drive.Concentric arrangements are also possible. The sprocket pairs of the chain conveyor systems assigned to the curved guide cylinder 3 are arranged eccentrically and axially offset from each other, with the chain not running over a sprocket being guided by a chain guide. As an alternative to a chain guide via a curve / groove, sprockets or deflection wheels could also be provided.

[0027] The drive for the chain conveyor systems in the delivery is provided by the two gears of the sheet guiding cylinder 3. The first sprocket main shaft 6 belonging to the leading edge gripper carriage is driven by the first gear, which is rigidly connected to the gripper system of the sheet guiding cylinder 3. The second sprocket main shaft 7 belonging to the trailing edge gripper carriage is driven by the second gear. The drive movement can be transmitted, for example, with the help of spur gears, from the aforementioned gears of the sheet guiding cylinder 3 to the respective sprocket main shafts 6, 7. The rotation of the gears of the sheet guiding cylinder 3 relative to each other automatically causes the format adjustment of the gripper systems of the chain conveyor systems. Separate drives or gears, such as superposition gears, are not required.

[0028] The leading edge gripper carriages contain gripper systems for securing the leading edges of sheets, which are preferably designed as clamping grippers. The clamping grippers have fixed gripper cuffs that interact with gripper fingers arranged on gripper shafts to secure the leading edges of sheets. The gripper fingers are designed to be cam-controlled and movable against the gripper cuffs. The trailing edge gripper carriages contain gripper systems for securing the trailing edges of sheets. These gripper systems can be designed as suction systems and / or clamping gripper systems. Preferably, the trailing edge gripper carriages also have gripper fingers arranged on a gripper shaft, which are cam-controlled and movable against gripper cuffs to secure the trailing edges of sheets. The trailing edge gripper carriages are designed to be format-adjustable relative to the leading edge gripper carriages, as described.

[0029] The leading edge gripper carriages pick up the sheets approximately at the upper surface line of the sheet guiding cylinder 3 at the gripper closure. The trailing edge gripper carriages also pick up the sheets from the sheet guiding cylinder 3. Alternatively, the trailing edges can also be gripped by the trailing edge gripper carriages at a distance from the surface area of ​​the sheet guiding cylinder 3 or on the way of the sheets to the sheet stack. The sheets can also be stabilized or secured in between by transfer systems not shown. A sheet fixed at the leading edge and trailing edge is transported in the delivery by the leading edge gripper carriage and the trailing edge gripper carriage along an ascending branch or, preferably, exclusively horizontally in the sheet travel direction BLR to the sheet stack.

[0030] In the preferred embodiment shown, the transfer of sheets from the sheet guide cylinder 3 to the gripper carriages and also their further transport to the sheet stack takes place horizontally on a straight path, which significantly simplifies sheet guidance. The horizontal sheet transport path allows the gripper carriages to be supported externally in the deflection area. This reduces the stresses and deformations caused by centrifugal forces, which enables the use of relatively small deflection radii and / or the use of low gripper carriage heights. Lower gripper carriage heights allow for a smaller and therefore significantly more effective dryer spacing. Alternatively or additionally, internal supports are also possible.

[0031] In a further development of the invention, not shown in detail, the delivery with gripper systems for the leading and trailing edges of the sheets is used in perfecting machines. In these machines, two gear couplings, which can be rotated relative to one another, meet in the gear train, namely in the perfecting unit on the storage drum and in the delivery unit on the sheet guiding cylinder 3. In order to reduce makeready times when adjusting the format, it is proposed according to the invention to carry out the format adjustment simultaneously on both gear couplings as follows. The front part of the machine before the perfecting unit is braked, as is the trailing edge gripper system 5 in the delivery unit. The two couplings on the storage drum and on the sheet guiding cylinder 3 are now released. An auxiliary drive moves the components arranged between the perfecting unit and the delivery unit, in particular the printing and / orCoating units after turning, and the leading edge gripper system 4 in the delivery into the desired position. An additional motor or an existing drive, e.g., for plate changing, can be used as an auxiliary drive. After the format setting, the coupling is finally engaged at both coupling points.

[0032] In the above-described refinement, in which the sheet transfer system includes a trailing edge guide element adjustable to the trailing sheet edges, the second gear of the sheet guide cylinder 3 is still connected to this trailing edge guide element for simultaneous format adjustment to the trailing sheet edge. The trailing edge guide element is thus set to the correct format when the second gear of the sheet guide cylinder 3 is rotated relative to the braked part of the machine. The trailing edge guide element is preferably designed as a suction bar. When the format is adjusted, this suction bar is automatically adjusted to the correct format, eliminating the need for a separate actuator for this bar.

[0033] The sheets, which are held by the leading edge gripper carriages at the leading edge and by the trailing edge gripper carriages at the trailing edge, are released above the sheet stack for stacking and are positioned against leading edge stops. A stacking system (not shown in detail) can be installed to slow down the sheets. This system can be designed as a re-gripper for gripping a sheet edge or as a pneumatic sheet brake. Preferably, however, the stacking system is designed as a gripper gripper, which takes the trailing edge of the sheet from the respective trailing edge gripper carriage at the gripper closure, brakes it, and deposits it on the delivery stack. Pressure-free corridors are not required.

[0034] The Fig.Figure 2 shows a side view of the drive of the two sprocket main shafts 6, 7 arranged in the delivery via the gears assigned to the sheet guiding cylinder 3. The two gears of the sheet guiding cylinder 3, which are located directly next to one another, drive the sprocket main shafts 6, 7 in the same direction on two levels via two intermediate gears 8 each. The sprocket main shafts 6, 7, in turn, drive the gripper carriages in the sheet travel direction BLR via the chains. By rotating the two gears assigned to the front of the sheet guiding cylinder 3 with the clutch open, the sprocket main shafts 6, 7 are set to the format. When the clutch between the gears is closed, the sprocket main shafts 6, 7 are driven for printing via two intermediate gears 8 each from the two interconnected gears via the main drive. List of reference symbols used 1 printing cylinder 2 transfer drums 3 sheet guiding cylinders 4 leading edge gripper system 5 Trailing edge gripper system 6 Sprocket main shaft of the front edge gripper system 7 Sprocket main shaft of the trailing edge gripper system 8 intermediate gears BLR sheet running direction

Claims

[1] Sheet processing machine with a sheet guiding cylinder (3) and a delivery, wherein a first drive wheel for driving the sheet guiding cylinder (3) is assigned to the front side and wherein the delivery comprises a leading edge gripper system (4) and a trailing edge gripper system (5) for transporting sheets at the leading edge and trailing edge, characterized by , that a further second drive wheel is assigned to the sheet guiding cylinder (3) and that the two drive wheels assigned to the sheet guiding cylinder (3) are arranged coaxially to one another. [2] Sheet processing machine according to claim 1, characterized by that the two drive wheels assigned to the sheet guiding cylinder (3) are arranged on the drive side and / or can be rotated relative to each other for format adjustment. [3] Sheet processing machine according to claim 1 or 2, characterized bythat the front edge gripper system (4) can be driven with one of the drive wheels and the rear edge gripper system (5) can be driven with the other drive wheel. [4] Sheet processing machine according to claim 1, 2 or 3, characterized by that the two drive wheels are connected by means of a clutch, in particular via a hydraulically actuated press fit. [5] Sheet processing machine according to at least one of the preceding claims, characterized by that the front edge gripper system (4) and / or the rear edge gripper system (5) is designed as a chain conveyor system and is arranged directly downstream of the sheet guiding cylinder (3). [6] Sheet processing machine according to at least one of the preceding claims, characterized bythat the machine has a sheet transfer system arranged directly upstream of the sheet guide cylinder (3) and that this sheet transfer system is designed optionally as a sheet transport cylinder, transfer drum (2) or as a sheet transfer drum having segments. [7] Sheet processing machine according to claim 6, characterized by that the sheet transfer system has a trailing edge guide element which can be driven by a drive wheel of the sheet guide cylinder (3), in particular a format-adjustable one. [8] Sheet processing machine according to at least one of the preceding claims, characterized by that a braking device is assigned to the rear edge gripper system (5) for format adjustment. [9] Method for operating a sheet-processing machine with a sheet guiding cylinder (3) and a delivery, wherein the sheet guiding cylinder (3) is driven by a first drive wheel and wherein the delivery comprises a leading edge gripper system (4) and a trailing edge gripper system (5) for transporting sheets at the leading edge and trailing edge, characterized by , that the sheet guiding cylinder (3) is assigned a further second drive wheel arranged coaxially to the first drive wheel and that the front edge gripper system (4) is driven by one drive wheel and the rear edge gripper system (5) is driven by the other drive wheel. [10] Method according to claim 9, characterized by that the format adjustment between the front edge gripper system (4) and the rear edge gripper system (5) is carried out by rotating the drive wheels of the sheet guiding cylinder (3) relative to each other.

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