EP4209349A1 - Sheet processing machine, use of the sheet processing machine, method for conveying sheets and use of sheet guiding elements containing deionization devices - Google Patents

Abstract

The invention relates to a sheet-processing machine (1) with sheet-processing units, the machine (1) containing at least two printing units (2) for processing sheets, the printing units (2) each containing a blanket cylinder (6) and a plate cylinder and a Blanket cylinder (6) of a printing unit (2) interacts with a sheet guiding cylinder (5) in each case, with a sheet conveying system (7) being provided between two sheet guiding cylinders (5), with the sheet guiding cylinder (5) and the sheet conveying systems (7) of the machine (1 ) the sheets are conveyed along a sheet conveying path, with a sheet guiding element beginning in the area of the sheet guiding cylinder (5) being provided below and along the sheet conveying path in one or all printing units (2), and with deionization devices (8) at least in the printing units (2) of the machine (1) are provided, which are arranged downstream of the printing gap of the first printing unit (2) of the machine (1) with respect to the sheet conveying direction (BFR). The invention also relates to the use of the sheet processing machine, a method for conveying sheets in a sheet processing machine (1) and the use of sheet guiding elements (9) containing deionization devices (8).

Description

The invention relates to a sheet processing machine, a use of the sheet processing machine, a method for conveying sheets in a sheet processing machine and the use of a sheet guiding element containing a deionization device in a sheet processing machine.

In sheet-fed printing presses, for example, increased electrostatic charging of the sheets can occur, especially at high speeds, particularly in printing units. In the printing units, this means that a printed sheet is attracted to the following sheet guide plates by being charged, even in spite of the air cushions that have been introduced, and the fresh ink on the underside is smeared on the sheet guide plates.

In the turning room, too, increased electrostatic charging of the printed sheets can occur, especially at high speeds. This leads to the sheets entering the cylinder gaps between the perfecting drum/impression cylinder and later the printing zone in a wavy manner. During a smoothing process on the printing cylinder surface, the sheet can no longer be pushed and is folded.

From the EP 0 306 682 A2 a device for conveying sheets through the printing zone of blanket cylinder and impression cylinder of a sheet-fed rotary printing machine is known, with the two unlike charges generating ionizing deionizing bars are arranged upstream to neutralize the sheet, which are directed at the sheet from below or from above, both z. B. be fed with a suitable AC voltage. This neutralization of charges creates unique Initial conditions for the subsequent positive charging of the arc. Another deionizing bar is arranged just before the transfer point of the printed sheet to the gripper systems of the sheet removal drum to eliminate the frictional connection between the sheet and a cover. The arrangement is quite complex and increases the adhesion of the sheets on the cylinder.

From the EP 1 155 834 A2 a device for removing electrical charges from flat material is known, the positive charge of a print medium lying on a metal plate being compensated for by means of first ionizer tips. Due to the remaining negative charge on the underside of the print medium, the discharged surface of the print medium is placed against another metal plate, with the negative charge being compensated by the downstream ionizing bar. This complex arrangement is not suitable for sheet guiding elements in sheet processing machines, in particular in turning devices of sheet processing machines.

From the EP 1 679 187 B1 or the U.S. 2006/150841 A1 a sheet guiding device with an electrically insulated, comb-shaped edge is known, with an unloading device for unloading the printing material sheet being arranged in the region of the edge. The arrangement in the edge close to the printing cylinder results in a reduced effect. The edge made of non-conductive material is subject to increased wear, especially in the critical area of the sheet transfer zone, and causes weaknesses in stability in the event of a crash. Furthermore, the arrangement of the discharge device in the concentric interconnect makes it more difficult to maintain the optimum electrode spacing, which leads to reduced effectiveness.

From the DE 197 55 745 A1 a device for electrostatically influencing signatures is known, with a flat charging electrode being applied to the guide surface of a sheet guide plate. By means of the device, the sheets are to be drawn onto the sheet guide plate by an attractive effect and are to be held in suspension by blast air flow. In reality, a stable flying height is through the arc not to keep such a facility constant. Furthermore, the flat contact electrode disturbs the nozzle distribution, which must be designed according to the need for arch support.

From the DE 100 38 774 A1 a fan unit in a printing machine is known which includes controllable ion fans. In a sheet turning device, too, a sheet of printing material can be guided and turned so that it adheres to the turning drum by means of a negative pressure that is generated. For this purpose, fan units containing ion fans can be arranged inside a cylinder or integrated into its surface. This is expensive and also not sufficiently effective.

From the DE 10 2007 049 643 A1 a device for turning a sheet while it is being conveyed through a printing press is known, with a brake arrangement for a sheet being arranged fixed to the frame. The braking arrangement consists of a generator for an alternating magnetic field and a pneumatic guide device for the sheet. When the sheet runs past the generator, a current is to be induced in the ferromagnetic material of the sheet or the printing ink on the sheet. A magnetic field emanating from the eddy current is intended to counteract the field of the generator so that the arc is slowed down. The effectiveness of this principle is questionable. The arcs are also not discharged since no ions are emitted by the generator.

From the DE 10 2010 028 702 A1 a turning device of a sheet-fed printing press is known, wherein an ionization device is assigned to the sheet transport path on or in connection with a storage drum, wherein the sheets guided on the storage drum or fed to the storage drum can be charged with electrical charges.

The DE 100 56 018 A1 shows a device for assisting in sheet guiding and depositing, in which a blown air blowing sheet guiding element encloses a deionizing device inside.

The DE 10 2008 001 165 A1 shows a sheet-guiding cylinder of a processing machine, the cylinder containing a base body on which a cylinder jacket that is electrically insulated relative to it is arranged.

The object of the invention is to create an alternative sheet processing machine or an alternative method for conveying sheets in a sheet processing machine or to improve sheet guidance in general in a sheet processing machine, in particular a turning device of a sheet processing machine. In particular, the safe sheet guidance is to be improved, especially in the area of a turning device, especially with low grammage or foil sheets.

According to the invention, the object is achieved by the features of an independent claim. Advantageous configurations result from the dependent claims, the description and the drawings. At this point, all of the embodiments of the invention disclosed in the claims of the originally filed documents are explicitly included in the description.

The invention has the advantage that an alternative sheet processing machine or an alternative method for conveying sheets in a sheet processing machine is created. In particular, sheet guidance is further improved, especially in the area of a turning device, which can advantageously lead to a significant increase in the performance of a sheet-processing machine, for example a sheet-fed printing press, in particular a sheet-fed offset printing press.

Particularly preferably, a sheet can be deionized after the sheet has been detached from a sheet-guiding cylinder, in particular a storage drum, in a turning device. The machine can be suitable or equipped to process sheets of low grammage and/or to process sheets of film. The machine can process, in particular print, sheet material with a grammage of more than 250 g/m ² , but preferably less than 250 g/m ² , particularly preferably less than 150 g/m ² and very particularly preferably less than 80 g/m ² and/or painted.

Preferably, one, two or more discharge electrodes can be arranged in the area of the sheet guiding element, in particular a sheet guiding plate of a turning device. The arrangement can be done as a cassette. For example, one or more discharge electrodes can be placed on the sheet guide plate, or one or more discharge electrodes can be embedded in the sheet guide plate. In this case, electrodes that are embedded are preferably positioned between insulators, the surfaces of which terminate in particular tangentially on the sheet metal guide plate.

The sheet guiding element, in particular sheet guiding plate, preferably delimits the long side of a turning space of a turning device at the bottom. The sheet guiding element, in particular sheet guiding plate, is preferably spaced apart from the cylinder tangent between a storage drum and a turning drum in such a way that the distance from the sheet corresponds to the optimum electrode spacing. Furthermore, a device, in particular a tension suction device on the storage drum, can be provided, which additionally stretches or tightens the sheet in the vicinity of the cylinder tangent between the storage drum and turning drum, so that not only the optimal electrode distance is maintained over the entire sheet length, but also the influence there can be made on the sheet, where it remains free of ion-binding contact with machine parts with masses on the top and bottom, so that the ions are little hindered in the activated deionizing Ambient air can pass, which ultimately leads to the maximum possible discharge of the arc.

A discharge cassette is preferably introduced into the sheet guiding element, in particular the sheet guiding plate, under the turn for discharging the sheets. A discharged sheet is thus freed from electrostatic force effects and can be smoothed out so that it can pass through a subsequent processing station or printing zone without waves and creases.

In the case of machines with perfecting devices, it makes sense, especially when processing substrates with a low grammage or made of foil material, to provide deionizing devices in addition to the deionization device in the perfecting unit in other or preferably all printing units and, if necessary, additional units and/or a delivery, since the printing material is always recharged in a pressure zone. Preference is given to using sheet guiding elements designed as sheet guiding plates and containing deionizing devices which, at a suitable distance from the sheet conveying path, particularly advantageously ensure optimum discharge and guidance of the printing materials at the same time.

Fig. 1:

Ausschnitt einer bogenverarbeitenden Maschine mit einem einem Bogenfördersystem eines Druckwerkes zugeordneten Bogenleitelement;

Fig. 2:

Vergrößerte Ansicht eines Kammfinger aufweisenden Bogenleitbleches mit Entionisationseinrichtung;

Fig. 3:

Perspektivische Ansicht des Bogenleitbleches mit Kammfingern und Entionisationseinrichtung;

Fig. 4:

Vergrößerte Ansicht eines eine Abdeckung aufweisenden Bogenleitbleches;

Fig. 5:

Abdeckung für Entionisationseinrichtung;

Fig. 6:

Perspektivische Ansicht eines eine Abdeckung aufweisenden Bogenleitbleches;

Fig. 7:

Ausschnitt einer bogenverarbeitenden Maschine mit einer Wendeeinrichtung mit einem eine Entionisationseinrichtung aufweisenden Bogenleitelement;

Fig. 8a:

Ausführungsform eines Bogenleitbleches der Wendeeinrichtung mit aufgesetzter Entladeelektrode;

Fig. 8b:

Ausführungsform eines Bogenleitbleches der Wendeeinrichtung mit integrierten Entladeelektroden;

Fig. 9:

Ausschnitt einer bogenverarbeitenden Maschine mit einem letzten Bogenführungszylinder und einer Auslage;

Fig. 10:

Bogenführungszylinder mit nachgeordneter Kettenradwelle und unterhalb der Kettenradwelle angeordnetem Bogenleitblech;

Fig. 11:

Bogenführungszylinder mit nachgeordneter Kettenradwelle und unterhalb der Kettenradwelle angeordnetem eine Abdeckung aufweisenden Bogenleitblech.

The invention is to be explained below by way of example. The associated drawings show the following schematically:

Figure 1:

Section of a sheet-processing machine with a sheet-guiding element assigned to a sheet-conveying system of a printing unit;

Figure 2:

Enlarged view of a sheet guide plate having comb fingers with a deionization device;

Figure 3:

Perspective view of the sheet guide plate with comb fingers and deionization device;

Figure 4:

Enlarged view of a sheet guide plate having a cover;

Figure 5:

cover for deionizer;

Figure 6:

Perspective view of a sheet guide plate having a cover;

Figure 7:

Section of a sheet processing machine with a turning device with a sheet guiding element having a deionization device;

Figure 8a:

Embodiment of a sheet guide plate of the turning device with attached discharge electrode;

Figure 8b:

Embodiment of a sheet guide plate of the turning device with integrated discharge electrodes;

Figure 9:

Section of a sheet processing machine with a last sheet guiding cylinder and a delivery;

Figure 10:

Sheet guiding cylinder with downstream sprocket shaft and sheet guide plate arranged below the sprocket shaft;

Figure 11:

Sheet guiding cylinder with a downstream sprocket shaft and a sheet guide plate having a cover arranged below the sprocket shaft.

The 1 shows, for example, a section of a sheet-processing machine 1, in particular a sheet-fed printing machine, here specifically one

Sheet-fed rotary printing machine, preferably in aggregate and in-line construction, in particular for foil sheet processing. In a preferred embodiment, the machine 1 is a foil sheet processing machine, in particular with appropriate equipment. An offset printing machine 1 can be operated accordingly in the offset process, but other printing processes such. B. screen printing, inkjet, etc. can be used in the machine 1. The machine 1 contains any number of sheet-processing plants, which, for example, as a system, primer, printing, coating, drying, inspection and/or finishing plant can be designed, for example, as an inline processing plant. In the aggregate and series construction, the successively arranged works of the machine 1 are preferably designed to be largely identical, it being possible, for example, for identically constructed substructure modules to be used. Furthermore, the machine 1 can contain a feeder for feeding sheets or an output device for outputting the processed sheets. The machine 1 could also have inline processing devices and/or one or more inline processing units, which can be designed, for example, as foil finishing units, cold foil units, calender units, stamping units, numbering units, screen printing units, perforating units, embossing units, etc. In particular, a turning device 3 is arranged between two works of the machine 1, with which the sheets are turned in a recto and verso printing mode. The machine 1 is preferably designed so that it can be switched between the modes of recto printing and recto and verso printing.

The machine 1 contains, in particular, at least two or a large number of printing units 2 and/or one or more coating units for processing sheets. The printing units 2 of the machine 1 preferably each contain a transfer cylinder or blanket cylinder 6 and a forme cylinder or plate cylinder that is not shown in any more detail. A blanket cylinder 6 of a printing unit 2 interacts with a respective sheet guiding cylinder, in particular a printing cylinder 5 . A sheet conveying system, preferably a sheet conveying drum 7 or a transfer drum or a transfer cylinder, is provided between two sheet guiding cylinders, in particular impression cylinders 5 . The impression cylinder 5 and the sheet conveyor drum 7 are double-sized here and the blanket cylinder 6 and the plate cylinder are single-sized. Single-size cylinders can accommodate about one and double-size cylinders can accommodate about two sheets of maximum format circumferentially at the same time. In an alternative embodiment, the sheet-guiding cylinders, in particular impression cylinders 5, or transfer or transfer drums could also be single-sized, triple-sized or larger.

The double-sized impression cylinders 5 or the sheet conveying drum 7 here preferably each have two gripper systems for fixing sheets to be conveyed, in particular foil sheets. These gripper systems, which are arranged diametrically opposite one another, for example in gripper channels, hold the sheet to be processed for conveying. The gripper systems preferably have fixed gripper pads, which interact with gripper fingers that can be moved via roller levers, for example by means of cams and cam rollers, for clamping the sheets. During their respective rotations, the gripper impacts of the printing cylinder 5 and sheet conveying drum 7 describe a gripper impact path that largely corresponds to the sheet conveying path. During the promotion, the sheets can rest on the respective cylinder or the lateral surface of a sheet guiding cylinder, in particular the printing cylinder 5 . The sheets are preferably transferred between the sheet guiding cylinders, in particular impression cylinders 5, and the sheet conveying systems, in particular sheet conveying drums 7, of the printing units 2 of the machine 1 in the gripper closure. The last unit of the machine 1 is preferably a delivery 4 with a delivery chain circuit downstream, which takes over the sheet from the last sheet guiding cylinder, in particular a pressure cylinder 5, by means of gripper carriages and promotes it to a delivery pile. For example, a last unit of the machine 1 before the delivery 4 can be designed as a printing, varnishing, drying, inspection or finishing unit such as an inline processing unit.

In the printing units 2 of the machine 1, the blanket cylinders 6 are operatively connected to the plate cylinders and known inking or inking and dampening units are arranged, which apply the appropriate printing ink to a printing plate stretched on the respective plate cylinder. A plate cylinder is inked by at least one, but preferably more, rollers of the associated inking unit or inking and dampening unit during its rotation. When the plate cylinder rolls on the blanket cylinder 6, the printing ink is applied to the blanket with a blanket, appropriate to the motif covered rubber cylinder 6 transferred. Between a blanket cylinder 6 and a printing cylinder 5, a printing gap or a printing zone is formed, through which the sheet to be printed is conveyed by the printing cylinder 5 by means of the gripper systems. In the nip, the printing ink is transferred from the rubber cylinder 6 to the sheet in accordance with the motif. The impression cylinder 5 has, in particular, a full-surface lateral surface for supporting the sheets to be conveyed, which forms the printing gap with the rubber blanket of the rubber cylinder 6 .

A plate cylinder and a blanket cylinder 6 of a respective printing unit 2 of the machine 1 preferably have a cylinder pin on each side, via which the cylinders are rotatably mounted in the frame of the respective printing unit 2 . Both the plate cylinder and the blanket cylinder 6 preferably have bearer rings (not shown) arranged on both sides. The plate cylinder bearers are in contact with the rubber cylinder bearers during the printing process and roll off one another under pressure. The bearer rings are preferably dimensioned in such a way that no significant torque transmission takes place between the cylinders during printing operation, ie no predetermined torque is transmitted via the bearer rings.

The machine 1 preferably has a drive wheel train which, particularly preferably as a continuous drive gear train, drives the sheet-guiding cylinders, in particular impression cylinders 5, of the printing units 2. The sheet conveying systems, in particular the sheet conveying drums 7 or transfer drums or transfer cylinders, are preferably also driven by the drive wheel train. The pressure cylinder 5 and the sheet conveyor drums 7 each have meshing gears that form the drive gear train. The drive wheel train is driven by at least one main drive motor, which drives in the center or preferably in the area of the front works of the machine 1. For example, the input of the main drive motor in the first plant in the sheet conveying direction BFR directly following first printing unit 2 take place, in particular on the shaft of the first printing cylinder 5 associated gear. The cylinders or drums are driven around their respective axis of rotation by the continuous drive wheel train. The blanket cylinders 6 of the printing units 2 are preferably also driven by the drive train of wheels. Other rotating bodies or rollers of the machine 1 or the printing units 2 can also be driven at least temporarily by the drive train of wheels, and these can also be designed so that they can be coupled to the drive train of wheels.

For example, an individual drive, in particular a plate cylinder direct drive, can be assigned to one or each plate cylinder of a printing unit 2 . Direct drives are in particular individual drives, the rotors of which are aligned and preferably mounted concentrically directly to the associated cylinders. During printing, the relevant plate cylinder can then be electronically synchronized with the blanket cylinder 6, which is preferably driven by the main drive motor via the drive train of wheels. For this purpose, the plate cylinder and/or blanket cylinder 6 can be assigned a rotary encoder, which can be connected to a quality control device, a control unit of the printing unit 2 and/or the machine control. Alternatively, the plate cylinder or cylinders can also be driven via the drive wheel train from the main drive motor, for example via clutches.

In a film sheet processing machine 1, sheet substrate containing film material or sheet substrate consisting of film material is processed, in particular printed and/or varnished. In particular, the sheet processing machine 1 has suitable equipment for processing film sheets. The film sheet processing machine is preferably designed as a film sheet printing machine at least for printing film sheets. In particular, the machine 1 can have a foil sheet processing package which is specially adapted to the foil material. For example, the machine 1 can have at least one example Printing units 2 contain an upstream primer unit and/or contain a special double-sheet control device and/or the gripper systems of the machine 1 can be adapted to the small thickness of the film sheet material and/or the printing inks and/or paints or dryers used can be adapted to the film material. Foil material can be, for example, foil made of PVC, PP, PS, PET. Furthermore, a machine 1 could also be used to process special papers, laminated papers or cardboard.

In foil printing in particular, the foil sheets are charged in each active printing unit 2 of the machine 1 . The foil sheets are extremely statically charged again, especially during each printing process. In particular, therefore, deionization devices 8 are provided at least in the printing units 2 and/or coating units of the machine 1, which are arranged downstream of the printing gap of the first printing unit 2 of the machine 1 with respect to the sheet conveying direction BFR. Deionization devices 8 are preferably provided in all the units of the machine 1 downstream of the first printing unit 2 . However, in a further development, a deionization device 8 can also be assigned to an installation unit and/or the first printing unit 2 of the machine 1 . The deionization devices 8 are provided in particular in each printing unit 2 and/or coating unit of the machine 1, with only one deionization device 8 being arranged in particular in each printing unit 2 and/or coating unit. A deionization device 8 of this type is also preferably provided in one or each additional plant, such as a lacquering, drying, inspection or finishing plant. In particular, charging devices for the targeted charging of cylinders or sheets are not provided.

The sheets, in particular foil sheets, are conveyed or transported along a sheet conveying path by the sheet guiding cylinders, in particular impression cylinders 5, and the sheet conveying systems, in particular sheet conveying drums 7, of the machine 1. In particular, below and along the sheet conveying path in one or all of the printing units 2 are provided with a sheet guiding element beginning in the area of the sheet guiding cylinder, in particular the printing cylinder 5 . Such a sheet guiding element is preferably designed as a metal sheet guiding plate 9 in particular, which extends in particular over the width of the machine. In particular, such a sheet guide plate 9 has comb fingers 10 in the area facing the sheet guiding cylinder, in particular the printing cylinder 5 . With respect to the sheet conveying direction BFR, the comb fingers 10 are in particular followed by a deionization device 8, the comb fingers 10 of the sheet guide plate 9 being made in particular partially or entirely of metallic material. Furthermore, the comb-shaped areas of the sheet guiding elements could be provided with blown air openings and in particular could be switched to blown air, so that a force acting pneumatically on the sheets can be generated in these areas. In particular, the sheets, in particular foil sheets, could therefore be peeled off the lateral surface of the upstream sheet guiding cylinder, in particular the printing cylinder 5, by the pneumatically acting comb fingers 10. The sheet guiding surfaces of the comb fingers 10 are accordingly associated with blower air openings that can be subjected to an overpressure. In particular, a blown air effect is exerted on the sheets conveyed along the sheet conveying path due to the overpressure lying above the ambient pressure.

A sheet guiding element, in particular sheet guiding plate 9, below a sheet conveying system, in particular a sheet conveying drum 7, can consist of a one-piece sheet metal or be composed of several sections. For example, an upstream guide piece can form a first area and a downstream guide piece can form a second area for sheet guiding. In this case, for example, a first section or partial sheet can extend from the casing of the sheet guiding cylinder, in particular the impression cylinder 5, to vertically below the axis of rotation of the sheet conveying drum 7. A second section or partial sheet can follow in the sheet conveying direction BFR and up to the lateral surface of the downstream sheet guiding cylinder, in particular the impression cylinder 5, rich. A deionization device 8 is assigned in particular to the first section of the sheet guiding element. In particular, the deionization device 8 is assigned to the sheet guiding element or the sheet guiding surface of the sheet guiding element in the area of the upstream sheet guiding cylinder, in particular the printing cylinder 5 . The deionization device 8 particularly preferably forms the sheet guiding surface in its arrangement area.

In particular, the subsection or a second region of the sheet guiding element, in particular sheet guiding plate 9, which is downstream in relation to the sheet conveying direction BFR is configured concentrically to the axis of rotation of the sheet conveying system, in particular the sheet conveying drum 7. In particular, the sheet guiding surface of the second section of the sheet guiding element, in particular the sheet guiding plate 9, is designed concentrically around the axis of rotation or the gripper impact path of the sheet conveying drum 7. The first section of the sheet guiding element, in particular the sheet guiding plate 9, in or from the region of the sheet guiding cylinder, in particular the impression cylinder 5, can have a sheet guiding surface which constantly approaches the rotation of the sheet conveying system, in particular the sheet conveying drum 7. The sheet guiding element is thus designed in a spiral shape. The first section can also be designed concentrically around an axis spaced apart from the axis of rotation of the sheet conveying drum 7 .

In particular, at least one fan 14 can be assigned to a sheet guiding element, in particular a sheet guiding plate 9, which can be controlled in particular to generate blown and/or suction air. A fan 14 is preferably arranged on the sheet guiding element, in particular a sheet guiding plate 9, in such a way that it generates blowing and/or suction air in the region of the sheet guiding surface of the sheet guiding element, in particular sheet guiding plate 9. Corresponding openings, for example Venturi nozzles, are associated with the sheet guiding element, in particular sheet guiding plate 9, facing the sheet conveying path. Outside any openings provided the sheet guiding element, in particular sheet guiding plate 9, but preferably has a closed sheet guiding surface.

In particular, a sheet guiding element, in particular sheet guiding plate 9, can be designed in such a way that a sheet guiding surface extends in the area of the lateral surface of the sheet guiding cylinder, in particular impression cylinder 5, beginning with the downstream sheet guiding cylinder, in particular impression cylinder 5, below the sheet conveying system, in particular sheet conveying drum 7. A first area of the sheet guiding element, in particular sheet guiding plate 9, beginning in the area of the upstream sheet guiding cylinder, in particular impression cylinder 5, can have the comb fingers 10 and be spaced further from the axis of rotation of the sheet conveying system, in particular sheet conveying drum 7, than a subsequent second area of the sheet guiding element, in particular the sheet guide plate 9. The comb fingers 10 and the first area of the sheet guide plate 9 preferably form a largely closed sheet guiding surface for the sheets.

The first area of the sheet guide plate 9 can begin in an angle of rotation of the sheet conveyor drum 7 that is spaced between 15° and 25°, in particular approximately 20°, from the transfer centers formed by the gripper closure between the upstream impression cylinder 5 and the sheet conveyor drum 7. The sheet guide plate 9 or the comb fingers 10 can be arranged at a distance of, for example, 2 mm to 50 mm, in particular between 25 mm and 30 mm, from the sheet conveying path formed by the gripper impacts of the sheet conveying drum 7. The first area of the sheet guide plate 9 preferably steadily approaches the axis of rotation of the sheet conveying drum 7 or the sheet conveying path.

In a second area of the sheet guide plate 9 adjoining the first area of the sheet guide plate 9 in the sheet conveying direction BFR, the sheets are preferably guided concentrically to the axis of rotation of the sheet feed drum 7 or a guide parallel to the gripper impact path of the sheet conveyor drum 7 or parallel to the sheet conveying path. The second area of the sheet guide plate 9 can, for example, be formed at a distance of 5 mm to 10 mm from the sheet conveying path. The second area of the sheet guide plate 9 can begin, for example, in a rotation angle range of 60° to 90° at a distance from the transfer center between the printing cylinder 5 and the sheet conveyor drum 7 . The sheet guide element, in particular the sheet guide plate 9, can thus be designed in such a way that its first area upstream with respect to the sheet conveying direction BFR has a multiple, for example double or triple, distance from the gripper impact path or the sheet conveying path compared to the second area downstream.

A deionization device 8 is preferably arranged in the first region of the sheet guide plate 9, with this being arranged downstream of the comb fingers 10 in the sheet conveying direction BFR when comb fingers 10 are provided. Comb fingers 10 can extend, for example, over an angular range of rotation of the sheet conveying drum 7 of approximately 5°. A deionization device 8 can follow the comb fingers 10 directly or extend over an angle of rotation of the sheet conveyor drum 7 of at least approximately 10°. The sheet guiding surface of the sheet guide plate 9 formed by the comb fingers 10 and/or the deionization device 8 approaches the axis of rotation of the sheet conveying drum 7 or its gripper impact path or the sheet conveying path, viewed in the sheet conveying direction BFR. For example, the first area of the sheet guide plate 9 can transition within an angle of rotation of the sheet conveying drum 7 of, for example, approximately 60° into the second area, which is configured largely concentrically with the sheet conveying path. The machine 1 can have further works or printing units 2, with some or preferably all of the works or printing units 2 comprising or containing sheet guiding elements, in particular sheet guiding plates 9, for sheet guiding. The sheet guiding elements, in particular sheet guiding plates 9, of the machine 1 are designed in particular to be structurally identical.

The 2 shows an enlarged view of a sheet guiding element configured as a sheet guiding plate 9 with a deionization device 8. The deionizing device 8 here has a cassette with at least one discharge electrode 12 arranged in the sheet guiding plate 9. The cassette can preferably be embedded in the sheet guide plate 9 below a sheet conveying system, in particular the sheet conveying drum 7, and also have a plurality of discharge electrodes 12, which are preferably of the same type. The cassette preferably has two discharge electrodes 12 here. In particular, the cassette is preferably arranged downstream of metal comb fingers 10, it also being possible for an upstream guide surface section 9.1 to be formed between the comb fingers 10 and the cassette. In the sheet conveying direction BFR, the cassette of the deionization device 8 is preferably directly adjoined by a downstream guide surface section 9.2 of the sheet guide plate 9. In this arrangement, the upstream guide surface section 9.1 and the downstream guide surface section 9.2 are part of a common guide surface of the sheet guiding element 9. The upstream guide surface section 9.1 and/or the downstream guide surface section 9.2 is particularly preferably also made of metal.

The sheet guiding element, in particular the sheet guiding plate 9, preferably encloses the sheet conveying system, in particular the sheet conveying drum 7, for example a transfer drum without a lateral surface, in a spiral shape. This means that the front part of the sheet guiding element, in particular the sheet guiding plate 9, is held at a greater distance from an axis of rotation of the sheet conveying system, in particular the sheet conveying drum 7, than the following part of the sheet guiding element, in particular the sheet guiding plate 9. The sheet guiding element, in particular the sheet guiding plate, then moves 9, preferably tangentially in a concentric radius to the sheet conveyor system, in particular the sheet conveyor drum 7, in order to realize the optimum electrode spacing in the areas of the furthest distance from the guide plate spiral, with the exception of the comb fingers 10. This means that the guide surface of the Sheet guiding element 9 approaches the radius of the sheet conveying drum 7 in the sheet conveying direction BFR and then guides it around concentrically with the radius of the sheet conveying drum 7.

The 3 shows a perspective view of the sheet guiding element, in particular sheet guiding plate 9, with comb fingers 10 and deionization device 8. The comb fingers 10 facing a sheet guiding cylinder, in particular the printing cylinder 5, contain spaced-apart, in particular metallic, finger elements between which the movable gripper fingers of the gripper systems of the sheet guiding cylinder, in particular the printing cylinder 5, can be passed. The comb fingers 10 can, for example, be arranged at a distance of a few millimeters, for example between 1 and 10 mm, preferably between 2 mm and 3 mm, from the lateral surface of the printing cylinder 5 . The deionization device 8 is arranged downstream of the comb fingers 10 with respect to the sheet conveying direction BFR. The deionization device 8 preferably contains both insulators 11 and one or more discharge electrodes 12 provided with electrical connections. The discharge electrodes 12 are connected to a controllable generator, in particular a high-voltage generator.

The insulators 11 of the deionization device 8 are each arranged transversely to the sheet conveying direction BFR, preferably over the entire width of the sheet guide plate 9, and have surfaces arranged perpendicularly to the sheet conveying path or to the sheet guiding surface of the sheet guide plate 9. Each discharge electrode 12 is arranged here in particular between two insulators 11 . An insulator 11 at the front with respect to the sheet conveying direction BFR adjoins the comb fingers 10, which are in particular metal, with its vertical or tangential surface. After the deionization device 8, the sheet guide plate 9 is preferably directly adjacent to a vertical or tangential surface of a rear or last insulator 11 with respect to the sheet conveying direction BFR.

The 4 shows an enlarged view of a sheet guide element having a cover, in particular a sheet guide plate 9. The complete deionization device 8 or the complete discharge cassette can be arranged in the sheet guide plate 9 in an exchangeable manner. Alternatively, the deionization device 8 can also be left in the sheet guiding element, for example rigidly or by means of displacement, in which case a cover, for example a cover part 13, can also close the opening. For example, the discharge-generating elements are covered by a cover made of non-conductive material, in particular plastic, which in particular has openings or cutouts. The cutouts are preferably arranged in such a way that the charge carriers of the discharge electrodes 12 are not affected. An arrangement above the discharge cassette is preferably carried out in such a way that the ions exit through preferably narrow slits and can thus reach the underside of the arc.

The figure 5 shows, for example, a cover for a deionization device 8 of a sheet processing machine, as described above. The cover is arranged as a cover part 13 transversely to the sheet conveying direction BFR above the deionization device 8 (not shown), in particular a discharge electrode 12, and in particular is made entirely of a non-conductive material, in particular plastic. The cover part 13 has a plurality of preferably uniformly arranged oblong holes oriented transversely to the sheet conveying direction BFR, which here, for example, have a dimension of 25 mm transversely to the sheet conveying direction BFR and 8 mm in the sheet conveying direction BFR. In this case, in particular each elongated hole is assigned an electrode tip of the deionization device 8, in particular the discharge electrode 12, which emits positive ions and an electrode tip which emits negative ions. The electrode tips indicated here act through the elongated holes, but in particular do not protrude into the sheet guiding surface of the cover. The electrode tips are therefore preferably below the surface or spaced from the Sheet guiding surface of the cover 13 arranged. Here, a discharge electrode 12 has electrode tips, which are arranged alternately, in particular equidistant from one another, and which emit positive and negative ions and which can work with or without blowing air support.

The 6 shows a perspective view of a sheet guide element having a cover part 13, in particular a sheet guide plate 9. The cover part 13 is inserted in the sheet guide plate 9 in such a way that a sheet guiding surface that is as trouble-free as possible and preferably continuous is formed. Blown air openings in the sheet guiding element, in particular sheet guiding plate 9, can be provided and are not shown. Venturi nozzles are preferably provided in the sheet guiding surface of the sheet guiding element, in particular of the sheet guiding plate 9, preferably blowing to the side. These are particularly preferably arranged on the inlet and/or outlet side with a blowing direction component towards the edges of the sheet guiding surface. This enables a resulting balanced floating height of the sheets on an air cushion, which is approximately in the gripper impact path, ie that the pressure forces of the flow on the sheet represent only a counterpart to its surface load, which is only 1 Pa for a 100 g/m ² sheet, for example and at z. B. a 28 g / m ² sheet almost 0 Pa. The forces acting on the sheet through the Venturi nozzles are therefore dependent on the flow gap between the sheet guiding surface and the sheet. If there is a deviation from the balanced levitation height, the force effect is always directed back to this balanced levitation height. The increase in pressure forces below the flying height as the sheet approaches the sheet guiding surface is comparatively higher than the increase in suction forces when moving away from the sheet guiding surface beyond the flying height.

The mechanism of action here is that disturbances are caused by the extreme adhesive forces between the sheet, in particular sheet of film, and the sheet-guiding cylinder, in particular impression cylinder 5, which result from the printing pressure become. When the sheets are transferred from the sheet guiding cylinder, in particular the impression cylinder 5, to the sheet conveying system, in particular the sheet conveying drum 7, the sheet is difficult to detach since the pull-off forces only act tangentially. As the movement progresses, the sheet intersects the sheet conveyor drum radius as a secant due to the pull-off forces in the sheet and the resulting "excess" of unwound sheet length allows the sheet adhering to the surface of the impression cylinder to continue to follow impression cylinder 5. As a result, the only really detaching radial components of the pull-off force, which previously only acted tangentially, increase, but these are still small and the sheet continues to follow the surface of the printing cylinder until the detachment loop of the sheet is peeled off by the pneumatically acting forces of the comb plate, in particular without mechanical contact. The air cushion generated by the venturi nozzles cannot participate in the withdrawal of the sheet from the impression cylinder 5, since the suction potential of the air cushion does not act on the regular sheet path or the balanced floating height.

Furthermore, the sheet is attracted by the electrostatic charge when it is pulled off in this way from the sheet guiding cylinder, in particular the impression cylinder 5, by the sheet guiding element, in particular the sheet guiding plate 9, and would touch down on this. The existing air cushion of the sheet guide plate 9, as a distributed load, could not create a balance against the unequally distributed field forces of the electrostatic charge and therefore could not create a state of levitation. Areas of intensive contact with the sheet guide plate 9 would occur. However, any intensive contact with the sheet guide plate 9 leads to visible scratches in the surface of the sheets, in particular of foil sheets, or to smearing, especially on sheets of paper. However, the above-described special design of the sheet guiding element, in particular a sheet guiding plate 9, is an effective distance-preserving measure for guiding sheets, in particular foil sheets, without scratching or smearing, on the sheet guiding surface under a sheet conveying system, in particular the sheet conveying drum 7, after the detachment of the sheet from the sheet guiding cylinder, in particular pressure cylinder 5 created. The solution created prevents contact of the sheet, in particular the foil sheet, with the sheet guiding element, in particular the sheet guiding plate 9, especially with the comb and the following parts of the guiding surface, and thus prevents scratches or smearing.

In the machine 1 there can also be a controller or also an automatic sensor-controlled regulation of one, several or all discharge electrodes 12 of one, several or also all deionization devices 8 of the machine 1 . For example, individual discharge electrodes 12 or multiple discharge electrodes 12 of a deionization device 8 or also multiple or all deionization devices 8 of the machine can be connected to a generator, in particular a high-voltage generator. The discharge effect can be adjusted by controlling the generator. In this case, for example, the intensity of the deionization device 8 can be controlled or regulated by measurement technology in such a way that it is possible to control or regulate the discharge in a manner adapted to the existing statics on the sheet, in particular the film sheet. Furthermore, in particular in the case of exchangeable unloading cassettes, they can be arranged at a different location on the machine 1 . In particular, such a cassette or deionization device 8 can be used in the turning room. The unloading cassettes can thus be designed to be interchangeable in the machine 1 or have a modular design.

The 7 shows a section of a sheet processing machine 1 equipped, for example, for film sheet processing, in particular as described above, with a turning device 3 and with a sheet guiding element. The perfecting device 3 is designed here as a three-drum perfecting device and contains a transfer drum 15, a storage drum 16 and a perfecting drum 17. The perfecting device 3 is preferably arranged between printing units 2 of the machine 1, with the transfer drum 15 being a sheet guiding cylinder, in particular an impression cylinder 5, of a printing unit 2 directly upstream or the turning drum 17 is a sheet guiding cylinder, in particular impression cylinder 5, of the following printing unit 2 is arranged downstream. The impression cylinders 5 are in turn operatively connected to a blanket cylinder 6 and this further to a plate cylinder (not shown) in the printing units 2, as described above. The machine 1 can be switched between the modes of recto printing and recto and verso printing, wherein in the recto printing mode, sheets are conveyed without turning by transferring the leading edge of the sheet between the drums.

The transfer drum 15 and the turning drum 17 of the turning device 3 are, for example, single-sized and the storage drum 16 is, for example, double-sized. For conveying the sheets, the transfer drum 15 has a gripper system (not shown) arranged in a gripper channel for clamping the sheets at the leading edge. In the gripper closure, the sheets are transferred to a gripper system (also not shown) of the storage drum 16 that is arranged in a gripper channel. From the storage drum 16, the sheets are clamped at the leading edge and fed to the turning drum 17 during the rotation of the storage drum 16. The turning drum 17 contains a gripper system (also not shown) for sheet conveyance, in particular grippers and/or suckers, which are pivotably mounted in the turning drum 17 . Alternatively, the turning drum 17 can also contain a pincer gripper system for taking over or conveying the sheets. Other cylinder arrangements or other cylinder sizes can also be used. For example, the transfer drum 15 can be double-sized.

In straight printing mode, the sheets are taken over by the gripper system of the turning drum 17 in a transfer center at the front edge of a gripper system of the storage drum 16. When turning a sheet in recto and verso printing, this sheet is guided past the transfer center by the storage drum 16 and gripped by the gripper system of the turning drum 17 at the trailing edge. This detected arc is then used during the Progress in rotation of the turning drum 17 is turned according to the principle of the rear edge turning, so that its old rear edge becomes the new front edge from its movement reversal and the old front edge lying on the storage drum 16 becomes the new rear edge. The turning device 3 is assigned a sheet guiding element to support the sheet guidance, in particular in the perfecting mode. For example, a sheet guiding element designed in particular as a sheet guiding plate 9 can be arranged below storage drum 16 and turning drum 17 to support sheet guiding. The sheet guiding element, in particular sheet guiding plate 9, can, for example, also be designed as a sheet guiding element, in particular sheet guiding plate 9, which can be displaced depending on the operating mode. Such a displaceable sheet guiding element, in particular sheet guiding plate 9, can be delivered to the sheet conveying path at least in the perfecting mode for sheet guiding.

The storage drum 16, which is not shown in detail, can, for example, have format-adjustable casing segments which mesh like combs when the format is adjusted and form the sheet-carrying casing surface. The two gripper systems, which are arranged diametrically opposite one another, of the double-sized storage drum 16 for the leading edges of the sheet are arranged on preferably stationary front casing segments. Fixing systems, in particular suction systems, for example rotary suction cups and/or tension suction cups, can be provided on the rear casing segments, which are adjustable relative to the front casing segments, for taking over and guiding the sheet trailing edges. The sheets can be tightened while lying on the storage drum 16 while the sheets are being conveyed from the transfer drum 15 to the turning drum 17 by means of rotary suckers, in particular longitudinally and/or transversely. Even when the turned sheet is pulled off the storage drum 16 by the turning drum 17, the sheet can preferably be tightened by the fixing systems, in particular suction systems such as the rotary suction cups or also tensioning suction cups in the tines of the rear adjustable casing segments of the storage drum 16.

To support the sheet guiding in perfecting printing, the sheet guiding element arranged below storage drum 16 and turning drum 17 can be designed to be adjustable, so that its sheet guiding surface is aligned at least approximately parallel to the sheet conveying path. The sheet conveying path corresponds at least approximately to a surface which is tangential to both the lateral surface of the storage drum 16 and the turning drum 17. The sheet guiding surface of the sheet guiding element, in particular of the sheet guiding plate 9, can also be slightly closer to the turning drum 17. The sheet guide element, in particular the sheet guide plate 9, has at least in some areas a flat guide surface 9.3, which is particularly preferably below the turning drum 17, in particular below the axis of rotation of the turning drum 17. A deionization device 8 is assigned to the sheet guiding element, in particular to the flat guide surface 9.3 of the sheet guiding plate 9. The deionization device 8 has at least one discharge electrode 12 for discharging an arc. The deionization device 8, in particular the at least one discharge electrode 12, causes a discharged sheet to be freed from electrostatic force effects so that it can be smoothed in such a way that it can pass through the subsequent printing gap or printing zone without waves and creases.

The Figure 8a shows an embodiment of a sheet guide plate 9 of the turning device 3 with an attached discharge electrode 12. The discharge electrode 12 is arranged transversely to the sheet conveying direction BFR, preferably across the width of the machine, and is provided with appropriate electrical connections. The discharge electrode 12 is preferably associated with the planar guide surface 9.3 of the sheet guide plate 9, with the planar guide surface 9.3 in the sheet conveying direction BFR being able to adjoin an area approaching the turning drum 17. Preferably, at least one fan 14 can be assigned to the sheet guiding element, in particular the sheet guiding plate 9, which can be controlled in particular to generate blown and/or suction air. To the Sheet guiding element, in particular sheet guiding plate 9, are assigned corresponding openings, for example venturi nozzles, facing the sheet conveying path. In particular, the fan 14 can generate suction and/or blown air at least in the area of the planar guide surface 9.3 of the sheet guide plate 9. The fan 14 can be provided in the area of the discharge electrode 12 on the side facing away from the sheet guide plate 9 . The sheet guiding element, in particular the sheet guiding plate 9, can also be designed in one piece or consist of several sections, with a fan 14 also being able to be assigned to an upstream section arranged largely below the storage drum 16.

The Figure 8b 12 shows an embodiment of a sheet guide plate 9 of the turning device 3 with an integrated deionization device 8. The deionization device 8 can have a cassette that is embedded in the sheet guide plate 9 and is in particular designed to be replaceable. The deionization device 8 preferably has a plurality of discharge electrodes 12 which are spaced apart from one another transversely to the sheet conveying direction BFR, preferably across the width of the machine. Between the discharge electrodes 12, which are preferably embedded here, insulators 11 are preferably positioned, the surfaces of which end tangentially on the sheet guide plate 9, in particular as already described above. The sheet guiding element, in particular sheet guiding plate 9, can preferably be assigned at least one fan 14 for generating blowing and/or suction air, in particular at least in the area of the flat guide surface 9.3, as described above. Furthermore, in the case of the at least one embedded discharge electrode 12, a cover can be provided in order to produce a largely closed sheet guiding surface in the region of the discharge electrode 12. A cover part, not shown, adapted to one or more discharge electrodes 12 and having openings can be assigned to the sheet guide plate 9 in particular directly above the discharge electrode 12 or discharge electrodes 12, in particular as described above. The cover part, not shown, can be designed or arranged as described above.

One of the described sheet guiding elements, in particular such a sheet guiding plate 9, is assigned to the transfer area between the storage drum 16 and the turning drum 17 in the machine 1. A sheet guide plate 9 delimits in particular the long side of the turning space at the bottom and is arranged at a distance from the cylinder tangent between storage drum 16 and turning drum 17 such that the distance to the sheet corresponds to the optimum electrode spacing. Furthermore, the fixing systems, in particular suction systems, for example rotary suction cups and/or tensioning suction cups, of storage drum 16 can be used to fix the sheet lying on storage drum 16, so that the sheet is additionally stretched or tightened in the vicinity of the cylinder tangent between storage drum 16 and turning drum 17 becomes. In particular, this means that not only is the optimum electrode distance maintained over the entire length of the arc, but the influence can be made there on the arc where it remains free of ion-binding contact with machine parts that are subject to mass on the top and bottom. This has the advantageous effect that the ions can pass into the activated deionizing ambient air with little hindrance.

The 9 shows, for example, a section of a sheet processing machine 1, in particular a film sheet processing machine 1, for example as described above, with a delivery 4. The machine 1 is accordingly preferably equipped for film sheet processing and is in particular designed as a film sheet processing machine, as already described above. The delivery 4 contains a sheet-promoting sheet conveying system not shown in detail, which accepts the sheets processed in the machine 1, for example printed and/or coated, from the last sheet-guiding cylinder and promotes or transports them to a delivery pile, not shown in detail. This sheet conveyor system is preferably designed as a chain conveyor system with two delivery chains each running laterally on the frame of the delivery 4, between which gripper carriages are equally spaced and arranged parallel to each other. The gripper carriages have sheet fixing systems with which the sheets to be conveyed are gripped at the front edge. The gripper carriage can take over the leading edges of the sheet from the last sheet guiding cylinder of the machine 1 in the gripper closure. The gripper carriages, which are driven and guided in an endless rotation, have gripper fingers that can be moved against fixed gripper impacts in order to take over the sheets, preferably on the front edge of the last sheet-guiding cylinder of the machine 1.

In the delivery 4, the gripper carriages are guided by the delivery chains on a gripper carriage path in the sheet conveying direction BFR up to the delivery stack, where the gripper carriages release the sheets for storage. To release the sheet, the clamped leading edges of the sheet are released by lifting the gripper fingers off the gripper pads fixed to the gripper carriage. The gripper fingers can be moved via cams and control levers via a gripper shaft on which the gripper fingers are fixed. With regard to the sheet conveying direction BFR, the delivery pile is preferably preceded by a sheet brake, which decelerates the sheets to be deposited after they have been released from machine speed to delivery speed. After being decelerated by the sheet brake, the sheets are aligned, for example, at the front, rear and/or side edge stops and placed neatly on the delivery pile. The delivery stack is lowered by a stack lifting drive during the sheet depositing process in such a way that the delivery stack surface forms an at least approximately constant deposit level for the coming sheets.

On the sheet conveying path to the delivery pile, at least one mechanical sheet guiding element is arranged in the delivery 4 below the sheet conveying path, which guides the sheets after the last sheet guiding cylinder on the way to the delivery pile. From the endlessly circulating gripper carriage of the chain conveyor system, the sheets printed on both sides in the machine 1, for example, are removed from the last Sheet guiding cylinder promoted to the delivery pile. The gripper pads circulating with the gripper carriage describe a gripper pad path which largely corresponds to the sheet conveying path or delimits it on one side and thus defines it. The last sheet guiding cylinder of the machine 1 is in particular a pressure cylinder 5 of the last printing, coating, drying, inspection or finishing unit, which in particular has an at least approximately closed lateral surface. The pressure cylinder 5 is preferably twice as large and contains two gripper systems arranged diametrically opposite one another in gripper channels, as already described above. These gripper systems have in particular also corresponding movable gripper fingers that limit or define the sheet conveying path. From these gripper systems, the leading edges of the sheet are taken over by the gripper carriages of the chain conveyor system in the gripper closure. To take over the leading edge of the sheet, the gripper fingers of the pressure cylinder 5 are set to the gripper fingers of the gripper carriage with a gap. This takeover of the leading edge of the sheet takes place in a transfer center in which the leading edge of the sheet is briefly fixed by both grippers.

The chain conveyor system in the delivery 4 has a sprocket shaft arranged adjacent to the last sheet guiding cylinder, in particular impression cylinder 5, with two sprocket wheels 18 which are arranged coaxially and spaced apart from one another and which are firmly connected to the sprocket shaft. The delivery chains run over the sprockets 18 and can be driven by them to revolve. The sprocket shaft can be driven, for example, via the continuous drive wheel train together with sheet conveyor systems and sheet guiding cylinders in the units or printing units 2 of the machine 1. Below the chain wheel shaft between the chain wheels 18 is arranged the sheet guiding element, which is preferably designed as a sheet guiding plate 9 arranged between the side walls and reaching over the width of the machine. This sheet guide plate 9 preferably has an at least approximately closed surface for guiding the sheets in a sliding and/or floating manner.

The sheet guide plate 9 can be provided with an ink-repellent coating. Furthermore, nozzle openings, in particular Venturi nozzles, can be assigned to the sheet guide plate 9 for the pneumatic guidance of the sheets.

For example, one or more blower boxes or fans 14 can be arranged below sheet guide plate 9, which can also be formed from assembled partial guide plates, via which blown air nozzles of sheet guide plate 9 can be supplied with blown air and/or suction air, so that between sheet guide plate 9 and a supporting air cushion can be formed on the sheets conveyed or transported by the gripper carriage, in particular for perfecting. The sheet guiding element, in particular sheet guiding plate 9, can be assigned a preferably deactivatable smoothing device. Such a smoothing device can be deactivated or is not used when sheets with fresh ink are transported or guided, for example in recto and verso printing, or also foil sheets. The sheet guiding elements, in particular sheet guiding plates 9, of the machine 1 are designed in particular to be structurally identical. In order to prevent the sheets from sticking to the delivery pile, dryers and/or powder devices (not shown in any more detail) can be provided in delivery 4 . It is also possible, in order to be able to control or regulate heating of the sheet guiding element, to integrate a coolant circuit in the sheet guiding element.

In particular, the sprocket shaft in the delivery 4 has no lateral surface for carrying the sheets. In a further development, in addition to the chain wheels 18 for the circulating delivery chains, the sprocket shaft can contain two or more support disks or suction disks or also individual suction cups, such as corner suction cups. For example, the support disks can be designed to be adjustable with or without corner suction cups or the suction disks to be axially displaceable on the respective sheet side edges. Such discs can also be adjusted axially automatically and/or independently of one another. Such disks contain, in particular, peripheral support surfaces which have a minimal axial have extension. Due to this extension of the support disks in the axial direction, a respective sheet can be fixed on the outer surface of the sheet guiding cylinder, in particular the impression cylinder 5, when the sheet is accepted. A sheet fall is thus avoided as long as the sheet is between the discs and the last sheet guiding cylinder, in particular the impression cylinder 5. The sheets are preferably pressed against the outer surface of the printing cylinder 5 in small press gaps by support elements arranged on brackets. The support elements can have elastic surfaces. Such discs are preferably also double-sized and can preferably have recesses for the circulating gripper carriage of the chain conveyor system.

The 10 shows a last sheet guiding cylinder, in particular printing cylinder 5, of the machine 1 with a downstream chain wheel 18 of the chain wheel shaft and a sheet guiding element arranged below the chain wheel shaft, in particular a sheet guiding plate 9 described above. A connecting line is drawn between the axis of rotation of the chain wheel 18 and the axis of rotation of the printing cylinder 5 which the transfer center is in the transfer area. The sheet guide plate 9 is arranged below the sprocket shaft, which has metal comb fingers 10 in particular in the area facing the printing cylinder 5 , in particular as already described for the printing unit 2 . In the area of the sheet guiding cylinder, in particular the impression cylinder 5, the sheet guide plate 9 is preferably further away from the axis of rotation of the chain wheel shaft or the chain wheel 18 than the adjoining areas of the sheet guide plate 9 in the sheet conveying direction BFR. The comb fingers 10 can, for example, be at a distance of a few millimeters, for example between 1 and 10 mm, preferably between 2 mm and 3 mm, to the outer surface of the pressure cylinder 5 can be arranged. In particular, the sheet guide plate 9 in the delivery 4 is designed at least approximately identically to the sheet guide plates 9 in the printing units 2 or units of the machine 1. This preferably ensures the same favorable sheet guiding conditions in the entire machine 1 .

The 11 shows a sheet guiding cylinder, in particular impression cylinder 5, for example as described above, with a downstream sprocket shaft and a sheet guide element arranged below the sprocket shaft and having a cover, in particular sheet guide plate 9, as described above. The sheet guide plate 9 shown in a side view has a cover, in particular a cover part 13 which contains non-conductive or non-metallic material or consists of non-conductive or non-metallic material as described above. The deionization device 8 can be removed, for example, from the sheet guiding element, in particular sheet guiding plate 9 . The deionization device 8 can be removed, for example, below or between sprockets 18 of the sprocket shaft. The deionization device 8 can be removed, for example, from the side and/or by displacing at least part of the sheet guide plate 9 . The cover, in particular the cover part 13, closes the opening required by the deionization device 8. The cover is preferably dimensioned or attachable in such a way that a continuous or almost full-surface sheet guiding surface of the sheet guide plate 9 is created. The cover part 13 can be designed or arranged as already described above.

How it works: A sheet conveying system in the perfecting device 3 and/or in a unit or printing unit 2, in particular a perfecting drum 17 or sheet conveying drum 7 or a gripper carriage in the delivery 4, pulls the sheets from a sheet guiding cylinder, in particular a storage drum 16 or a Impression cylinder 5, taken over and guided past a deionization device 8 along the sheet guiding element, in particular the sheet guiding plate 9, on the sheet conveying path. In the area of a transfer drum or a sprocket shaft, a device can be provided as a further development, which additionally guides the sheet in the vicinity of the gripper application path in a defined manner only at the edges, so that the optimum electrode spacing is maintained over the entire sheet length and the sheet does not prematurely touch sheet guide plate 9 and falls below said optimum electrode spacing.

The sheets, in particular foil sheets, are detached from the lateral surface of the sheet guiding cylinder, in particular the impression cylinder 5, by the sheet guiding element, in particular the sheet guiding plate 9, preferably with a spiral shape. In particular, the comb fingers 10 of the detachment loop of the sheet deviate at a suitable distance when it is pulled off the lateral surface. Allowing a minimum pull-off loop advantageously increases the detaching radial component of the pull-off forces. By arranging the Venturi nozzles along the guiding contour of the sheet guiding element in connection with the associated balanced floating height of the sheets under the gripper impact path, the suction forces of the air cushion can act on the sheets located on the regular sheet path. In this way, the sheet is kept on the outside of the radius of the gripper track and the release loop is kept small.

The at least one discharge electrode 12, which is embedded in particular at the start of the guide plate, causes a charge equalization on the sheet until there is sufficient charge neutrality, so that the sheet is not attracted by the sheet guide element, in particular sheet guide plate 9, as an electrical conductor. The deionization device 8 in particular provides positive and negative ions in order to be able to compensate for the changing charge states on the sheet surface. A deionization device 8 is used in particular in each printing unit 2 or unit of the machine 1, because the sheet, in particular foil sheet, is extremely recharged during each printing process.

The sheets are optimally discharged in particular by the deionization device 8 of the or each printing unit 2, preferably each unit, the turning device 3 and/or the delivery 4. By unloading, it is possible to move the sheet to the next conveyor system, for example a pressure cylinder 5 or a gripper carriage, while it is constantly floating. to be supplied without the sheet being scratched by contact with the sheet guiding element, in particular a sheet guiding plate 9 . The one or more discharge electrodes 12 of a respective deionization device 8 ensure in particular an active discharge with both positive and negative ions. Provided generators work preferably in a range of 3 to 6 kV, optimally with a high voltage of at least approximately 4.5 kV. The high voltage can also be set depending on the electrostatic charge that has been determined. A respective sheet is discharged by the deionization devices 8, so that the deionized sheets, smoothed out by electrostatic forces, lie on the sheet guide plate 9 or the air cushion generated by the sheet guide plate 9. The sheets remain free of deformation and smearing over the entire machine 1.

List of reference numbers used

1

machine

2

printing unit

3

turning device

4

display

5

pressure cylinder

6

rubber cylinder

7

sheet feed drum

8th

deionization device

9

sheet guide plate

9.1

upstream guide surface section

9.2

downstream guide surface section

9.3

flat guide surface

10

comb finger

11

insulators

12

discharge electrodes

13

cover part

14

Fan

15

transfer drum

16

storage drum

17

turning drum

18

Sprocket

BFR

sheet conveying direction

Claims (35)

Sheet-processing machine (1) with sheet-processing units, the machine (1) containing at least two printing units (2) for processing sheets, the printing units (2) each containing a blanket cylinder (6) and a plate cylinder and a blanket cylinder (6) of a printing unit (2) each interacting with a sheet guiding cylinder (5), with a sheet conveying system (7) being provided between two sheet guiding cylinders (5), the sheets being guided along by the sheet guiding cylinders (5) and the sheet conveying systems (7) of the machine (1). a sheet conveying path, with a sheet guiding element beginning in the area of the sheet guiding cylinder (5) being provided below and along the sheet conveying path in one or all printing units (2), and with deionization devices (8) being provided at least in the printing units (2) of the machine (1). which are downstream of the printing gap of the first printing unit (2) of the machine (1) with respect to the sheet conveying direction (BFR). Sheet processing machine according to claim 1, wherein the machine (1) contains a large number of printing units (2) and one or more varnishing units for processing sheets and deionization devices (8) are provided at least in the printing units (2) and varnishing units of the machine (1). , which are arranged downstream of the printing gap of the first printing unit (2) of the machine (1) with respect to the sheet conveying direction (BFR). Sheet-processing machine according to claim 1 or 2, wherein such a deionization device (8) is also provided in one or each additional unit, such as a drying, inspection or finishing unit. Sheet-processing machine according to Claim 1, 2 or 3, in which a feed unit and/or the first printing unit (2) of the machine (1) also has a Deionization device (8) is assigned. Sheet-processing machine according to Claim 1, 2, 3 or 4, with only one deionization device (8) being arranged in each printing unit (2) and/or coating unit. Sheet processing machine according to claim 1, 2, 3, 4 or 5, wherein the sheet guiding elements, in particular sheet guiding plates (9), of the machine (1) are constructed identically. Sheet processing machine according to claim 1, 2, 3, 4, 5 or 6, wherein the sheet guide plate (9) in the delivery (4) is at least approximately identical in construction to the sheet guide plates (9) in the printing units (2) or units of the machine (1st ) is executed. Sheet processing machine according to claim 1, 2, 3, 4, 5, 6 or 7, wherein the complete deionization device (8) or the complete discharge cassette is arranged in the sheet guide plate (9) so that it can be exchanged. Sheet-processing machine according to claim 1, 2, 3, 4, 5, 6, 7 or 8, wherein the unloading cassettes in the machine (1) are designed to be interchangeable or have a modular structure. Sheet processing machine according to Claim 1, 2, 3, 4, 5, 6, 7, 8 or 9, wherein such a sheet guiding element is designed as a sheet guiding plate (9) and has comb fingers (10) in the area facing the sheet guiding cylinder (5), whereby with respect to the sheet conveying direction (BFR), the comb fingers (10) are each connected to a deionization device (8). Sheet-processing machine according to claim 10, wherein the sheet-guiding surfaces of the comb fingers (10) are assigned blown air openings that can be subjected to an overpressure. Sheet-processing machine according to claim 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 or 11, wherein the first section of the sheet-guiding element (9) from the area of the sheet-guiding cylinder (5) has a continuous rotation axis of the sheet-conveying system (7) has approximate sheet guiding surface. Sheet-processing machine according to Claim 10, 11 or 12, in which the comb fingers (10) of the sheet guide plate (9) consist partially or entirely of metallic material. Sheet processing machine according to claim 10, 11, 12 or 13, wherein a first area of the sheet guiding element (9) beginning in the area of the upstream sheet guiding cylinder (5) has the comb fingers (10) and is spaced further from the axis of rotation of the sheet conveying system (7) than a subsequent second area of the sheet guiding element (9). Sheet processing machine according to claim 10, 11, 12, 13 or 14, wherein a largely closed sheet guiding surface for the sheets is formed by comb fingers (10) and the first area of the sheet guide plate (9). Sheet processing machine according to claim 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14 or 15, wherein the sheet guide plate (9) or comb finger (10) from the gripper pads of a Sheet conveying drum (7) formed sheet conveying path are arranged at a distance of 2 mm to 50 mm, in particular between 25 mm and 30 mm. Sheet-processing machine according to claim 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15 or 16, wherein the comb fingers (10) and/or deionization device (8 ) Formed sheet guiding surface of the sheet guide plate (9) seen in the sheet conveying direction (BFR) steadily approaches the axis of rotation of the sheet conveying drum (7) or the sheet conveying path. Sheet-processing machine according to claim 10, 11, 12, 13, 14, 15, 16 or 17, wherein the comb fingers (10) are at a distance of between 1 and 10 mm, preferably between 2 mm and 3 mm, from the lateral surface of a printing cylinder (5) are arranged. Sheet-processing machine according to claim 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17 or 18 for film sheet processing with a delivery (4), wherein the A delivery (4) with a delivery chain circuit is arranged downstream of the last unit of the machine (1), which takes the sheets from the last sheet guiding cylinder (5) by means of gripper carriages and conveys them to a delivery pile, whereby on the sheet conveying path to the delivery pile in the delivery (4) below the sheet conveying path at least one mechanical sheet guiding element is arranged, which guides the sheets after the last sheet guiding cylinder on the way to the delivery pile and wherein a deionization device (8) is assigned to the first part of the sheet guiding element. Sheet processing machine according to claim 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18 or 19, wherein the machine (1) prints a foil sheet -Processing package, which is specially adapted to the film material, in particular film made of PVC, PP, PS, PET. Sheet processing machine according to claim 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19 or 20, wherein the machine (1) at least one primer contains and/or contains a special double-sheet control device and/or the gripper systems of the machine (1) are adapted to the small thickness of the film sheet material and/or printing inks and/or varnishes or dryers used are adapted to the film material. Sheet processing machine according to claim 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20 or 21, wherein the machine ( 1) contains at least one primer unit arranged upstream of the printing units (2). Sheet processing machine according to claim 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21 or 22, wherein dem Sheet guiding element (9) in the delivery (4) is assigned a deactivatable smoothing device. Sheet processing machine according to claim 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22 or 23, the discharge-generating elements being covered by a cover made of non-conductive material, in particular plastic, which in particular has openings or cutouts which are arranged in such a way that the charge carriers of the discharge electrodes (12) are not influenced. Sheet processing machine according to claim 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23 or 24, the intensity of the deionization device (8) being controlled or regulated by measuring technology in such a way that it is possible to control or regulate the discharge in a way that is adapted to the existing static on the sheet, in particular the film sheet. Sheet processing machine according to claim 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24 or 25 with a turning device (3), wherein in the turning device (3) sheet by a sheet conveyor system (17) from a sheet guiding cylinder (16) and can be conveyed in the sheet conveying direction (BFR) on a sheet conveying path, with a sheet guiding element (9) being provided below and/or along the sheet conveying path and with a deionization device (8) being assigned to the sheet guiding element (9). Use of the sheet processing machine according to claim 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25 or 26 for processing foil sheets, where the foil material is foil made of PVC, PP, PS, PET. Method for conveying sheets in a sheet-processing machine (1), the sheets being conveyed in a plurality of printing units (2) or in a plurality of printing units (2) and a delivery (4) of the machine (1), the sheets being conveyed in the printing units ( 2) are printed in printing columns, with the sheets in the printing units (2) or in the printing units (2) and the delivery (4) each being taken over by a sheet conveying system (7, 18) from a sheet guiding cylinder (5) and transported in the sheet conveying direction (BFR ) are conveyed on a sheet conveying path along a sheet guiding element (9), the sheets in the printing units (2) or in the printing units (2) and the delivery (4) each being fed by a below and along the sheet conveying path in the area of the sheet guiding cylinder (5) starting sheet guiding element (9), the sheets being guided past a deionization device (8) assigned to the sheet guiding element (9), positive and negative ions being made available by the deionization device (8) in order to compensate for the changing charge states on the sheet surface and wherein the sheets are guided past a deionization device (8) after each printing gap in the printing units (2) or in the printing units (2) and the delivery (4). Method according to claim 28, wherein the sheets in at least one unit (2) and/or the delivery (4) of the machine (1) are taken over by a sheet conveying system (7, 18) from a sheet guiding cylinder (5) and in the sheet conveying direction (BFR). a sheet conveying path, the sheets being guided by a sheet guiding element (9) arranged below and along the sheet conveying path, the sheets being first guided on a sheet guiding surface of the sheet guiding element (9) which has a deionization device (8) and which is further from a rotational axis of the associated sheet conveying system (7, 18) as a sheet guiding surface of the sheet guiding element (9) adjoining it in the sheet conveying direction (BFR). Method according to Claim 28 or 29, in which the sheets are peeled off the lateral surface of the sheet guiding cylinder (5) by comb fingers (10) of the sheet guiding element (9) beginning in the area of the sheet guiding cylinder (5) which in particular are pneumatically acting and/or metallic and to one or the deionization device (8) are conducted. Method according to claim 28, 29 or 30, wherein the sheets are guided after one or the deionization device (8) concentrically to the axis of rotation of the sheet conveying system (7, 18) to a downstream sheet guiding cylinder (5). Method according to Claim 28 or 29, in which the discharge is adapted by means of one or more deionization devices (8) to the electrostatics of a respective arc or a plurality of arcs by means of a control or regulating device. Method according to Claim 28, 29 or 32, wherein, depending on the current order, a cover (13) with or without openings for producing a Sheet guiding surface is used on the deionization device (8). Method according to Claim 28, 29, 32 or 33, in which the machine (1) is used to process or print low-grammage printing materials of less than 150 g/m ² and preferably less than 80 g/m ² and/or film sheets. Use of a sheet guiding element (9) containing a deionization device (8) in all printing units (2) and a delivery (4) or in all printing units (2), a turning device (3) and a delivery (4) of a sheet-fed printing press, in particular a sheet-fed offset printing press Aggregate and series construction.

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