DE102011080321B4 - Gripper arrangement on bow-leading cylinders - Google Patents

Abstract

Sheet-fed printing machine, with a feeder, at least one printing unit or coating unit for printing or coating printed sheets (B), with a boom, and with at least one processing unit (1) integrated into the sheet-fed printing machine, the processing unit (1) being one of the printing sheets (B) leading cylinder (7) provided with grippers (6), as well as a counter-element (10, 20) assigned to the cylinder (7), with devices on or in connection with the cylinder or cylinders (7) leading the printed sheet (B) are provided, by means of which the distance of the counter element (10, 20) from the surface of the printed sheet (B) guided on the cylinder (7) by means of the gripper (6) is minimized in relation to the height of the gripper (6), at least a processing station (inkjet print head (24), dryer (20)) before and / or after the printing gap (S) between the counter element designed as a cylinder (10) and the impression cylinder (7) for marking or post-treatment a surface coating is assigned to the surface in such a way that the cylinder (10) is assigned to the coated printing material (B) guided on the cylinder (7) leading to the sheet in a touching or non-touching manner, characterized in that on the surface (16) or the surface elements of the sheet-guiding cylinder (7), at least in the areas associated with the or all of the counter-elements (10, 20), a support element (13, 14) changing the diameter of the sheet-guiding cylinder (7) is provided or that a sheet-guiding cylinder (7 ) is provided with an enlarged working diameter compared to a normal diameter (16) and / or that the diameter of the cylinder (7) guiding the sheet is reduced in the area of the gripper (6) in such a way that the surface (16) of the cylinder (7) guiding the sheet is provided. and the height of the grippers (6) in relation to the counter elements (10, 20) are approximately the same level (F1, F2).

Description

The invention relates to a device in a sheet-fed printing press according to the preamble of claims 1, 2 or 3.

In sheetfed presses to be printed sheets are transferred within the sheet transport path of a sheet leading cylinder to the next sheet leading cylinder. Here, sheet transport drums and impression cylinders are common devices. In order to guide the sheet and to be able to hold securely devices are integrated with grippers in the drums / cylinders. The grippers are designed as fold-out fingers, rest on the front edge of the peripheral surface of the drums / cylinders in the direction of transport of the printed sheets and are therefore beyond their circumference, based on the working diameter of the drums / cylinders. For transferring the printed sheet, an exact transfer position is defined in each case, which is fixed unchangeable due to the bearings of the drums / cylinder in so-called side stands of the sheet-fed press. The transfer positions occurring in the sheet-fed printing machine can not be changed without major technical effort, since most of the other functions of the sheet-fed printing machine itself, but also of associated with this processing systems or further processing units in relation to the transport cycle of the press sheets are based on these positions.

From the EP 1 057 626 B1 a gripper device for a printing press is known. The gripper device is used to transport sheets on a sheet edge in a printing press. The gripper device is provided with a plurality of grippers and spaces provided between the grippers, into which mating grippers dip when sheets are fed or removed. In the interstices movable sheet supports are arranged, which are movable in the gripper plane in a range of movement of the gripper device in which the interstices are released by the counter-grippers. The movable sheet supports are in a sheet transfer by the dipping into the interstices counter gripper out of the gripper level and the range of movement of the counter-gripper out movable.

From the EP 1 242 299 B1 is a sheet-processing printing machine known. This sheet-processing printing machine should be equipped with at least one flexographic printing or cylinder of an offset printing unit and an impression cylinder. In this case, the impression cylinder should have at least one sheet leading gripper. The gripper is located in the sheet leading position completely within the cylinder described by the peripheral surface of the impression cylinder. In this case, adjacent cylinders such as a printing cylinder of a flexographic printing unit or a cylinder of an offset printing unit have no plate clamping channel. The gripper is illustrated by a gripper arm and a gripper pad. At least the gripper arm is movable relative to the gripper pad. In this case, the bow leading position of the gripper is adjustable and at least one such arc leading position of the gripper should lie completely within the cylinder described by the peripheral surface of the impression cylinder.

Furthermore, from the US 3,163,558 A a combined sheet transport drum and an associated gripper assembly known. The document shows a gripper system commonly used in gravure printing. The gripper elements are arranged completely within the cylinder described by the peripheral surface of a counter-pressure cylinder.

The EP 0 045 374 A1 Finally, shows a gripper device on cylinders for printing machines, especially sheet-fed rotary printing machines. The gripper device is arranged within the peripheral surface of a pressure cylinder covered with a blanket. The printing cylinder is also impression cylinder for a covered with a blanket offset printing cylinder. The gripper device is suitable for perfecting.

Printing cylinder and a multifunctional cylinder form the sheet delivery base module.

Furthermore, the shows DE 10 2008 059 309 A1 a coating device with a separate cylinder drive. In an aggregate for the film transfer to a printing press, a drive configuration is provided in which at least one plate cylinder of a proposed for the film transfer coating unit is provided with a direct drive. Furthermore, an inking unit associated with the plate cylinder can be attached to the plate cylinder and uncoupled from the main request of the printing press.

Furthermore, the shows DE 10 2010 029 423 A1 a method and apparatus for producing a patterned layer. In a processing machine, an application unit formed by a film transfer unit deforms a lacquer layer on a substrate on its surface in a press nip. For this purpose, a structural layer is pressed onto the substrate coated with the lacquer layer, wherein the pressure takes place only on the impression cylinder and the further cylinder. Following the press nip, the structural layer and the varnish-coated substrate are transported synchronously on the impression cylinder during drying.

A modification of the impression cylinder is also in WO 2010/050618 A1 described, where this serves the purpose of using an inkjet printhead to a bow-leading cylinder.

In the printing press, the integration of various work steps in a machining operation is increasingly required. In addition to the classic flat-bottom and high-pressure processes also new printing processes and various finishing steps of the printed material. The combination of offset and flexographic printing is to be regarded as the standard in the printing industry, although finishing steps such as cold foil transfer, embossing and stamping components must be partially or widely regarded as being realized. One technology used in the safety and finishing sector for the packaging industry is the holographic effect. This visual enhancement is achieved by order of previously equipped with this feature films, so-called holographic films, or by a cost-effective inline work process, in which corresponding structures are embossed directly into a previously applied paint layer. This process of a paint-embossing process is also known as Cast & Cure. A pre-embossed film is brought into contact with the still-liquid paint, so that their contours are filled by the paint. The ideally radiation-curing lacquer is then dried or cured (eg by UV radiation). If the structured or structuring film is removed again from the paint surface, the cured paint with a structured surface remains on the substrate.

Proceeding from this, the object of the present invention is to provide a novel cylinder arrangement in which gripper arrangements can not interfere with work processes at the level of the cylinder circumference.

This object is achieved by a device in a sheet-fed press with the features according to claims 1, 2 or 3.

According to the invention, a guide arrangement is provided in the area of the surface of a sheet which rests flat on the printing sheet and guides the cylinder by means of grippers, which is integrated in the sheet-fed printing machine and guides the printed sheet on a face relative to the nominal diameter of the raised level.

At or in connection with the printing sheet leading cylinders so that means are provided by means of which the distance of the or each counter assembly is minimized by the surface of the sheet opposite additional working equipment on these cylinders.

• (1) Es gibt keinen über den Druckbogen überstehenden Greiferrücken mehr beim Bogentransport.
• (2) Inkjet-Anwendungen werden erleichtert bzw. die Qualität wird erhöht, da ein geringerer Abstand zwischen Inkjetdruckkopf und Bedruckstoff ohne Berücksichtigung von überstehenden Greifern eingestellt werden kann.
• (3) Im Kaltfolientransfer wird die Folienführung durch die überstehenden Greiferrücken nicht mehr beeinflusst. So kommt zu keiner Faltenbildung mehr und es wird eine Folienapplikation mit höchster Qualität vom Druckanfang bis zum Druckende erzielt
• (4) Auch im so genannten Cast & Cure-Verfahren wird die Folienführung nicht mehr durch die überstehenden Greiferrücken gestört. Es gibt keinen Übertragungslücken beim Prägen der Strukturfolie in die Lackoberfläche und es wird eine Oberflächenstruktur mit höchster Qualität vom Druckanfang bis zum Druckende hin erzielt. Als Oberflächenstruktur kann auch eine Glättung oder ein Glänzendmachen der Oberfläche mittels eine glatten Folie verstanden werden.
• (5) Prägen, Stanzen, Rillen etc. Einsatz von Prägezylindern ohne Kanal-Ausfräsung für die Greifer wird möglich. Einsatz von Sleeves als Zylinderbezüge wird möglich, damit ergeben sich Kostenreduzierung und Stabilität des Druckprozesses.
• (6) Das Beschichtungsmodul bleibt für die ursprünglichen Anwendungen zum Lackieren oder zum Drucken einsetzbar.
• (7) Teure Änderungen der Zylinderpositionen mit Einfluss auf die gesamte Druckmaschine sind nicht nötig. Kostengünstige Integration in bestehende Druckmaschinen. Modular betrachtet ist nur ein Zylinder einer Druckmaschine zu ändern, so in einem Prägemodul, in Verbindung mit Greifersystemen, deren Greiferrücken über der Umfangswirklinie liegt.
• (8) Einstellarbeiten oder Umkonfigurierung der Maschineneinstellungen und konstruktiven Ausführung hinsichtlich der Übergabepositionen der in den Druckwerken einer Bogenrotationsdruckmaschine verarbeiteten Druckbogen, z. B. im Hinblick auf Art, Ausführung und Einstellung von Greiferöffnungskurven und Greiferauflagen, sind nicht erforderlich. Die Übergabepositionen bleiben unbeeinflusst.

The invention has the following advantages in comparison to the prior art or avoids the following disadvantages:

• (1) There is no longer a protrusion of the gripper over the sheet when transporting sheets.
• (2) Inkjet applications are made easier or the quality is increased because a smaller distance between the inkjet printhead and the printing substrate can be set without taking into account protruding grippers.
• (3) In cold foil transfer, the film guide is no longer influenced by the protruding gripper backs. So no more wrinkles and there is a film application with the highest quality from the beginning of the print to the end of printing achieved
• (4) Also in the so-called Cast & Cure process, the film guide is no longer disturbed by the protruding gripper backs. There is no transmission gap when embossing the structure film in the paint surface and it is achieved a surface texture with the highest quality from the beginning of printing to the end of printing. The surface structure can also be understood to mean smoothing or glossing of the surface by means of a smooth film.
• (5) Embossing, punching, grooving, etc. Use of embossing cylinders without channel milling for the grippers becomes possible. Use of sleeves as cylinder covers is possible, resulting in cost reduction and stability of the printing process.
• (6) The coating module remains usable for the original applications for painting or printing.
• (7) Costly changes of the cylinder positions with influence on the entire printing press are not necessary. Cost-effective integration into existing printing machines. Viewed modularly, only one cylinder of a printing machine is to be changed, for example in a stamping module, in connection with gripper systems whose gripper back lies above the circumferential line.
• (8) adjustments or reconfiguration of the machine settings and structural design with respect to the transfer positions of the processed in the printing units of a sheet-fed rotary printing press sheet, z. B. with regard to the type, design and adjustment of gripper opening curves and gripper pads are not required. The transfer positions remain unaffected.

The present invention enables processing with minimal loss of format on the working films both for the above-mentioned cold foil transfer and for the coating embossing process according to the Cast & Cure method in a sheetfed offset press. Usually, the sheet transport is accomplished by means of gripper elements in a sheet-fed offset printing press. These protrude several millimeters the cylinder circumference addition. If the structuring film or the transfer film at the circumference of a cylinder against the painted or provided with an adhesive surface substrate surface, it comes in the vicinity of the gripper back to areas where no contact with the transfer film or the structuring film is made, as the corresponding film is lifted there from the gripper back several millimeters. This loss is not acceptable, at least for economic reasons.

The distance between the structuring film or the transfer film to the substrate surface is minimized by modifying the cylinder construction:
The printing material on the printing cylinder is supported such that its surface is at or near the radius of the highest point of the gripper elements, so that no disturbance by lifting the film in the vicinity of the gripper back of importance for structuring the paint surface. The formation of the printing cylinder surface or the printing cylinder radius should be such that the substrate is as "soft" brought to the enlarged pressure gauge to minimize the mechanical stress, but at the same time as quickly as possible, the working diameter is achieved to the printable format to use optimally. In order to optimize this compromise, in relation to the above-mentioned measure, a construction height minimized gripper tip construction can be used. This is also conceivable if the film device is arranged behind the precisely matched offset printing units. The claim to the transfer accuracy of the passport system is possibly reduced in this case. The construction element can be selected depending on printing material thickness. In particular, the "start edge", which is responsible for the deformation of the printing material, may need to be adjusted individually. The attachment of the element on the cylinder can be done form-fitting but also by clamping or z. B. magnetic forces or a combination thereof. Another possibility is the use of a cylinder with a corresponding outer diameter, ie no diameter adjustment by a separate element. The arrangement of such a printing unit can be done as a film device between dock and boom exclusively in combination with a glue factory (ideally offset printing unit) ("stand-alone"). However, it is also conceivable to arrange the printing units in a hybrid application, ie in any order combined with one or more printing units. These printing units can all be equipped with the same printing process or with any other method, eg. B. sheetfed offset, flexographic printing or in-line processes such as embossing, punching, etc.

Preferred embodiments of the invention will become apparent from the dependent claims and the description below.

Embodiments of the invention will be described, without being limited thereto, with reference to the drawings. Showing:

1 : a printing unit of a sheet-fed rotary printing press,

2 : A detail of a device according to the invention in a printing unit of the sheet-fed rotary printing press and

three : a detail of the device according to the invention.

Combined with 1 is a basic arrangement in a printing unit or coating plant 1 a sheet-fed printing machine described.

The coating plant 1 has a bow guide drum 2 for feeding sheet B to the coating unit 1 on. The bowing drum 2 may be designed as a so-called skeleton drum, wherein a roughly disc-shaped drum body arranged offset by 180 degrees gripper devices with grippers 6 for holding and guiding the sheet B carries. To guide the sheet B can then below the sheet guide drum 2 an example pneumatically assisted sheet guiding device 4 be provided. The bowing drum 1 is in an axis 5 mounted non-displaceably and rotatably and driven by a gear, not shown.

The printed sheets B are using the gripper 6 to corresponding gripper devices with grippers 6 a counter-pressure cylinder 7 to hand over. The impression cylinder 7 is also in an axis 8th non-slidably and rotatably mounted. The gripper devices with the grippers 6 are in two offset by 180 degrees on the cylinder body arranged cylinder channels 9 arranged. The synchronization of the rotational movement of the impression cylinder 7 to bowing drum 2 takes place by means of a gear connection, not shown here between the two cylinders / drums 2 respectively. 7 ,

• – als Drucktuchzylinder zur Bildung eines Offsetdruckwerkes,
• – als Formzylinder zur Bildung eines Lackmoduls oder Flexodruckwerks,
• – als Transferzylinder zur Bildung eines Folientransferwerkes,
• – als Prägezylinder zur Bildung eines Prägewerkes,
• – als Eindruckzylinder zur Bildung eines Eindruck- oder Nummerierwerkes,
• – als Stanzzylinder zur Bildung eines Stanzwerkes oder
• – als Glättzylinder in Verbindung mit einem UV-Druck- oder Lackwerk.

The impression cylinder 7 assigned is a working cylinder 10 on a radially displaceable axis 11 rotatably mounted. The working cylinder 10 is also by a not shown gear connection with the other cylinders / drums 2 respectively. 7 driven synchronously. The working cylinder 10 acts with the impression cylinder 7 in a working slit S together. In the working gap S, the surface of the working cylinder acts 10 on one on the impression cylinder 7 held sheet B a. The working cylinder 10 can be used in different functional characteristics:

• As a blanket cylinder for forming an offset printing unit,
• As a forme cylinder to form a paint module or flexographic printing unit,
• As a transfer cylinder to form a film transfer station,
• As embossing cylinder to form a stamping plant,
• As an impression cylinder for the formation of an impression or numbering mechanism,
• - As a punching cylinder to form a stamping or
• - As a smoothing cylinder in conjunction with a UV printing or coating unit.

In the respective embodiments, the working cylinder 10 then assigned corresponding additional units for execution of the respective work processes.

Furthermore, in the coating plant 1 in a working area above the impression cylinder 7 and the working cylinder 10 assigned to the side an installation space 12 arranged for additional work units. In the installation space 12 can special working units both the working cylinder 10 as well as the impression cylinder 7 assigned and each be provided on and off. In particular, imprints, numbering machines, digital printing units or measuring and marking devices may be suitable for this purpose.

The impression cylinder 7 points in the area of his two the grapples 6 in the direction of rotation downstream work surfaces each have a radius R1. The working cylinder 10 has a radius r1 in the area of its working surface.

To adapt the effective cylinder surface of the impression cylinder 7 in their level compared to the grippers 6 is inventively provided that each a support element 13 respectively. 14 on each of the working surfaces of the impression cylinder 7 is attached. The impression cylinder 7 So it is with the help of the support element 13 and the support element 14 in the area ever one of the work surfaces on each a new larger radius R2 increases. The new larger radii R2 relate to the two new effective surfaces on the impression cylinder 7 , The new effective surfaces are with the lines F1 and F2 in 1 referred to in terms of the two work surfaces. Here it must be ensured that these two effective surfaces F1, F2 have mutually identical radii R2. This is the only way to avoid that the operation of the printing press is changed in an inadmissible manner and the process parameters for both work surfaces is not retained in an exact manner as identical to each other.

The diameter of the impression cylinder 7 can by means of two editions 13 respectively. 14 which are designed as a foil, sheet, sheet, plate or the like and can be attached by means of a glued or by magnetic means or by mechanical clamping acting to be increased. Then the position of the so-called gripper back of the gripper lies 6 in the state when the grippers 6 closed, at or even below the level of the requirements 13 manufactured new enlarged cylinder diameter. Ultimately, however, it is important that the surface of one on the new work surface F1, F2 on one of the pads 13 respectively. 14 resting pressure sheet B at least at the level of the gripper back of the gripper 6 lies.

• 1. durch die Festlegung des erforderlichen Zylinderdurchmessers und/oder
• 2. durch das einzusetzende Material (Metall, Kunststoff, Gummi, etc und/oder
• 3. durch anwendungstechnische Vorgaben (Matrize, Patrize, farbabweisende Oberfläche etc.).

In addition to the possibilities of adhesion and magnetic adhesion can also with the help of appropriately designed clamping devices in the cylinder channels 9 the impression cylinder 7 each same conditions 13 respectively. 14 Different types on the work surfaces of the impression cylinder 7 be stretched. The technical characteristics of the conditions to be used 13 respectively. 14 is selectable under different aspects:

• 1. by determining the required cylinder diameter and / or
• 2. by the material to be used (metal, plastic, rubber, etc and / or
• 3. by application specifications (die, patrix, ink-repellent surface, etc.).

As described, the impression cylinder 7 and the working cylinder 10 synchronized by means of gears. This results in a clear work process the compulsion to adapt the diameter of the cylinder to each other. To the relative speeds, one speaks here of a so-called settlement between the impression cylinder 7 and the working cylinder 10 Match the diameter of the working cylinder 10 also be increased, even if he should have no gripper units. This is done on the working cylinder 10 a corresponding edition 15 attached, the a new radius r2 on the effective surface of the working cylinder 10 manufactures. The new effective surface is with the line f1 in 1 designated.

The technical application conditions in the selection of an edition 15 for the working cylinder 10 are by the criteria for the conditions 13 respectively. 14 , on the impression cylinder 7 are intended to be used.

The for an increase in diameter of the working cylinder 10 at the same time enlarged diameter at the impression cylinder 7 required clearance in the working gap S between impression cylinder 7 and working cylinder 10 can be made by means of a commonly available paper thickness adjustment. Here, the axis acting as the axis of rotation is 11 of the working cylinder 10 in a known manner by eccentrically acting adjusting means (not shown here) radially relative to the impression cylinder 7 displaced. This shift is in 1 with the directional arrow A and the lined circular hints to the axis 11 and the working cylinder 10 implied

• a) Ein üblicher Arbeitszylinder 10 lässt sich mittels eines Stellmechanismus um etwa 1,2 mm vom Gegendruckzylinder 7 radial abstellen.
• b) Der Radius R1 des Gegendruckzylinders 7 wird um 0,6 mm auf den neuen Radius R2 erhöht (die Radien R1 werden für beide Arbeitsflächen um jeweils 0,6 mm erhöht).
• c) In Relation dazu ist der Radius r1 des Arbeitszylinders 10 um 0,3 mm auf den neuen Radius r2 zu erhöhen.
• d) Damit ergibt sich insgesamt eine Verringerung der Achsabstände zwischen Arbeitszylinder 10 und Gegendruckzylinder 7 um 0,9 mm.
• e) Bis zur maximalen Stellbewegung des Abstandes der Zylinder 7, 10 in dem Arbeitsspalt S verbleibt damit immer noch eine tatsächlich ausführbare Einstellung für die Anpassung an variable Papierstärken von 0,3 mm.

By way of example, the technical design may look like this:

• a) A usual working cylinder 10 can be adjusted by about 1.2 mm from the impression cylinder by means of an adjusting mechanism 7 turn off radially.
• b) The radius R1 of the impression cylinder 7 is increased by 0.6 mm to the new radius R2 (the radii R1 are increased by 0.6 mm for both work surfaces).
• c) In relation to this, the radius r1 of the working cylinder 10 is to be increased by 0.3 mm to the new radius r2.
• d) This results in a total reduction of the axial distances between the working cylinder 10 and counter-pressure cylinder 7 by 0.9 mm.
• e) Up to the maximum adjusting movement of the distance between the cylinders 7 . 10 in the working gap S thus still remains an actually executable setting for the adaptation to variable paper thicknesses of 0.3 mm.

By comparatively simple constructive adjustments, the adjustment range for the working cylinder 10 opposite the impression cylinder 7 can also be increased, so that the range of substrates, with the coating unit 1 are to be processed, can be extended in terms of substrate thicknesses.

The use of the pads 13 respectively. 14 on the impression cylinder 7 can be selected in terms of their thickness to determine the new radius R2 so that the thickness of the processed sheet B in determining the level of the surface of the printing material B against the grippers 6 is included (see also the illustration in 2 ). So you can with standardized substrates with conditions 13 respectively. 14 - and also the edition 15 - Get along with comparatively small thickness. This is accompanied by an expandability for the application of the printing press and a minimal change in the process parameters.

As a result of the solution proposed according to the invention, processing of printed sheet B is virtually continuous. The surface of the printed sheet B resting on the impression cylinder now lies at least at the level of the upper edge of the gripper back of the grippers projecting beyond the nominal cylinder surface 6 , This is a disturbance of the rotation surface by the gripper 6 not possible anymore.

Now, as a working cylinder 10 Also, a cylinder without cylinder channel can be used, which would be cheaper and easier to handle. Furthermore, could work on the cylinder 10 so-called sleeves are used, which can be mounted as a sleeve-shaped cylindrical elements for clamping on a cylinder surface.

An essential starting point for the invention is the use of specific and in particular digital printing functions. Therefore, it is still anxious to integrate additional functions in the press. This may be specifically the inkjet print. This is in terms of achievable print quality limitations that result from a maximum distance to the substrate to be printed. Normally, by the over the outer circumference high gripper back of the gripper 6 on the impression cylinder 7 a minimum distance of an inkjet printhead or more inkjet printheads to the substrate surface conditionally. Such a minimum distance can be significantly reduced or minimized by the inventively proposed modification of the cylinder construction or configuration. This allows the effective distance to sheet B on a sheet leading impression cylinder 7 For example, configure inkjet printheads in the best possible way and the print quality is significantly improved. Inkjet printheads can in the installation space 12 the impression cylinder 7 assigned to be installed.

In contrast to the offset printing process, in which a color transfer takes place by direct contact of plate, blanket and impression cylinder, ink transfer is non-contact with the inkjet system. Therefore, with a known relation of cylinder circumference and speed virtually any printed image can be printed in correct proportions and at any speed.

For the same reason, a suitably used inkjet system can virtually with any outside diameter of the impression cylinder 7 work together. Due to the machine, only the transfer point from and to the adjacent sheet transport drums has to be used 2 be stationary ie arranged in the same height and angular position.

Therefore, the printing material on the impression cylinder 7 be supported so that its surface at least on the radius of the highest point of the gripper 6 (Gripper back) is located and for this reason, then an inkjet printhead as closely as necessary on the sheet B can be installed. The formation of the surface or the radius R2 of the impression cylinder 7 should take place in such a way that the printing material B is brought to the enlarged pressure gauge or radius R2 with as constant a transition as possible from the nominal diameter or radius R1. As a result, the mechanical stress of the printing material B can be minimized. At the same time, however, the working diameter (radius R2) is to be achieved on the shortest possible rotation angle in order to optimally utilize the maximum format of the printing sheet B to be printed.

With the increased radius R2 or diameter of the impression cylinder 7 and the arrangement of a so-called gripper bar on the nominal working diameter, the accurate positioning of the digital print image is difficult. The gripper bar is in each case the counter element of the gripper three respectively. 6 on the bow leading cylinders 2 . 7 , In known Abwicklung - ie rotation ratios of the cylinder 7 . 10 to each other, a controlled with respect to the machine angle print imaging is conceivable. This control can also be printed substrate-specific with respect to its thickness. Also conceivable is a control technology combination of the print head with an upstream print image capture (here a print start indicator is sufficient), which then determines the positionally accurate pressure from machine speed and sheet position.

In 2 is a corresponding inventive arrangement on a sheet leading impression cylinder 7 presented in a detailed manner.

On the work surfaces of the impression cylinder 7 of which only one is shown here is a support element 13 . 14 applied. The attachment can be done by clamping, gluing or by magnetic mounting. This support element 13 . 14 is in the range of a gripper system with grippers 6 attached to the impression cylinder 7 for guiding the printed sheets are arranged, shortened, so that the effective cylinder surface here down to the nominal surface 16 the impression cylinder 7 excluded.

The nominal surface 16 is also in the range of grippers 6 at so-called gripper impacts 17 reached. These are the cylinder channel 9 on the impression cylinder 7 assigned and act with on a corresponding arc leading cylinder (eg., Sheet transport drum 2 ) arranged and the local grippers associated further gripper cuffs together. The gripper serves 17 form gripper serve surfaces 18 against the grippers 6 be used to pinch the sheet B. The support elements 13 . 14 can z. B. in connection with the attachment of the gripper serves 17 at the edge of the cylinder channel 9 the impression cylinder 7 be attached. The gripper serves 17 are usually dependent on the substrate to be processed and its thickness relative to the surface of the impression cylinder 7 adjustable. This can be done continuously or in coarser processing stages.

The impression cylinder 7 assigned is an inkjet printhead 20 at an adjustable distance to the effective surface 16 the impression cylinder 7 and with a correspondingly smaller distance with respect to the surface of the support element 13 . 14 positioned.

The thickness of the support element 13 . 14 can be selected depending on the thickness of the printing material B. In this case, the support element 13 . 14 depending on the thickness of the printing material B is chosen so thick that the surface to be printed (sheet B) sufficiently close to the inkjet printhead 20 is arranged to ensure good print quality. The inkjet printhead 20 In turn, there must be a minimum distance to the back surface of the gripper 6 comply. The attachment of the support element 13 . 14 on the impression cylinder 7 can be positive or non-positive, ie by clamping, gluing or z. B. magnetic forces or a combination thereof.

The working radius R2 is then over a relatively short rotation angle by means of a transition contour 19 starting from the gripper surface 18 reached to the radius R2. The printed sheets B can this transition contour 19 easily follow even with larger sheet thicknesses.

The inventive design of the inkjet printhead 20 be brought up to a minimum distance X to the surface of the sheet B. This results in an optimal print image, since the ink droplets of the inkjet print head can reach the substrate surface almost unaffected by environmental influences. The effective area F1, F2 of the impression cylinder 7 resting pressure sheet B is at or even above the rear surfaces of the gripper 6 ,

Another possibility is the use of a counter-pressure cylinder 7 with a contouring of the outer diameter corresponding already to the mentioned parameters of substrate thickness, gripper height and printhead arrangement. The transition contour 19 is then incorporated between gripper pads and work surface in the cylinder. Then you have to no diameter adjustment be made by a separate support element. However, the impression cylinder in this case is only suitable for certain production purposes.

The present invention furthermore makes possible a transfer process already mentioned above for producing metal layers on printed sheets or for imaging a fine contour embossed from a film surface into a lacquer layer in a sheetfed offset press with minimum format loss. The fine contour can also be designed as a high gloss or matt gloss, which can be generated by means of appropriate types of films on the paint surface. The transfer printing of metal layers in an offset printing unit is referred to as cold foil transfer. The cold foil transfer is usually carried out at the beginning of a printing process in a multi-color printing press. For the fine embossing or gloss embossing of a film in a flexible lacquer layer, the term Cast & Cure method has become common. In contrast, this Cast & Cure process for producing fine structures or gloss effects on printed sheets is usually carried out on a lacquer layer which was applied to a printed sheet at the end of a printing process.

In sheetfed offset presses, the transport of the sheet-shaped substrates or substrates is accomplished by default by means of gripper elements. The grippers protrude within the thickness of the material of the so-called gripper fingers that hold sheets on the sheet-guiding cylinders or drums, up to several millimeters beyond the cylinder circumference.

If the structuring or glossy film for the coating embossing process is applied to the coated substrate surface at the circumference of a cylinder, or if the metallized transfer film for cold foil transfer is located on the circumference of a cylinder against a substrate surface provided with an adhesive image, the gripper back is created in the vicinity of the action area , d. H. as at the beginning of the sheet, where the grippers hold the sheet, surface areas in which there is no contact of the substrate to the structurally or glossy film or transfer film, since the film is lifted there by the gripper fingers by several millimeters.

The distance of the structurally or glossy film or the transfer film to the printing substrate surface is minimized by a modification of the cylinder construction:
The substrate 4 on the printing cylinder 1 is supported such that its surface at or near the radius of the highest point of the gripper elements three is located, so there is no interference by lifting the film 5 in the vicinity of the gripper back of importance for the structuring of the paint surface. The formation of the printing cylinder surface or the printing cylinder radius should be such that the substrate is as "soft" brought to the enlarged pressure gauge to minimize the mechanical stress, but at the same time as quickly as possible, the working diameter is achieved to the printable format to use optimally. In order to optimize this compromise, in relation to the above-mentioned measure, a construction height minimized gripper tip construction can be used. This is also conceivable in particular if the film device is arranged behind the precisely matched offset printing units. The claim to the transfer accuracy of the passport system is possibly reduced in this case. The construction element 2 can be selected depending on printing stock. In particular, the "start edge", which is responsible for the deformation of the printing material, may need to be adjusted individually. The attachment of the construction element 2 on the cylinder 1 can be done form-fitting, but also by clamping or magnetic forces or by pneumatic means or a combination thereof. Likewise, the use of a cylinder with a corresponding outer diameter is possible, ie it must then be no diameter adjustment by a separate element.

For the described arrangement according to 1 and three for using a transfer or stamping foil web 21 It is known to provide a film feed from a supply roll and a film removal on a take-up roll. In between is the film web 12 by means of guide rollers 22 . 23 within the coating plant (may be a sheetfed offset printing unit or a coating unit of a sheetfed press) over the working cylinder 10 (may be the blanket cylinder of the offset printing unit or the forme cylinder of the coating unit) placed on the substrate coated with lacquer and after a drying section on the circumference of the impression cylinder 7 (see dryer 24 ) again over a foil guide roller 23 detached from the sheet and removed, so that they can be wound up again. The laying of the film on the paint layer can also be done by means of a channelless deflection roller, since the impression cylinder 7 now no more grippers survive, which could interfere with the unwinding.

Furthermore, the film winding and unrolling according to one in the DE 10213651 A1 described cylinder with a fastening device for a flexible, upper elevator in a processing machine done. There is on a cylinder, the lower elevator made of a flexible substrate at intervals with several underlay forms. The elevator is received in tension shafts and movable on the cylinder circumference, wherein in each case a base mold can be positioned to the upper elevator. Thus, the structurally or glossy film can be stored on the cylinder itself and, if necessary, so if the fine structure of the film surface is no longer fully effective, be readjusted by further transport.

It is necessary the working cylinder 10 in diameter to the impression cylinder 7 adapt. In this case, the diameter can be selected so that the surface velocities of both cylinders are the same when maintaining the appropriate Achsabstandsverhältnisse. In a driven directly with its own drive motor working cylinder 10 is the speed adjustment adjustable. When using one opposite the transfer or stamping foil web 21 equipped with very low static friction covering the working cylinder 10 can also be a constant slip between the film web and cylinder 10 be used. This is the surface of the transfer or embossing foil 21 pressed into the coating of the printing material and kept tight by the slip against the train and so safely guided.

LIST OF REFERENCE NUMBERS

1

Printing unit, paint module, coating unit

2

Sheet guide drum

3

grab

4

Sheet guiding device

5

axis

6

grab

7

Impression cylinder

8th

axis

9

cylinder gap

10

working cylinder

11

axis

12

installation space

13

edition

14

support element

15

support element

16

Nominal surface

17

gripper

18

Gripper surface

19

Transition contour

20

Inkjet printhead

21

stamping foil

22

Folienumlenkrolle

23

Folienumlenkrolle

24

dryer

R1, R1, r1, r2

radius

F1, F2, f1

effective surface

A

displacement direction

S

working gap

B

sheet

X

working distance

Claims (5)

Sheet-fed printing machine with a feeder, at least one printing unit or coating unit for printing or coating printed sheets (B), with a delivery arm, and with at least one processing unit integrated into the sheet-fed printing machine ( 1 ), the processing unit ( 1 ) one leading the printed sheets (B) and with grippers ( 6 ) provided cylinder ( 7 ), as well as a cylinder ( 7 ) associated counter element ( 10 . 20 ), wherein at or in connection with the one or more of the printing sheets (B) leading cylinders ( 7 ) Means are provided by means of which the distance of the counter element ( 10 . 20 ) from the surface of the cylinder ( 7 ) by means of the gripper ( 6 ) Signature (B) in relation to the height of the grippers ( 6 ), wherein at least one processing station (inkjet print head ( 24 ), Dryer ( 20 )) before and / or after the pressure gap (S) between the cylinder ( 10 ) executed counter element and the impression cylinder ( 7 ) is assigned to the marking or aftertreatment of a surface coating of the surface, such that the cylinder ( 10 ) on the cylinder leading to the bow ( 7 ) coated coated printing material (B) touching or not touching is characterized in that on the surface ( 16 ) or the surface elements of the sheet leading cylinder ( 7 ) at least in that of the or all of the counter elements ( 10 . 20 ) assigned to the diameter of the arc leading cylinder ( 7 ) changing support element ( 13 . 14 ) or that a sheet of leading cylinders ( 7 ) with a relative to a normal diameter ( 16 ) enlarged working diameter is provided and / or that the diameter of the sheet leading cylinder ( 7 ) in the area of the gripper ( 6 ) is reduced such that the surface ( 16 ) of the arc leading cylinder ( 7 ) and the height of the grippers ( 6 ) against counter elements ( 10 . 20 ) have an approximately equal level (F1, F2). Sheet-fed printing machine with a feeder, at least one printing unit or coating unit for printing or coating printed sheets (B), with a delivery arm, and with at least one processing unit integrated into the sheet-fed printing machine ( 1 ), the processing unit ( 1 ) one leading the printed sheets (B) and with grippers ( 6 ) provided cylinder ( 7 ), as well as a cylinder ( 7 ) associated counter element ( 10 . 20 ), wherein at or in connection with the one or more of the printing sheets (B) leading cylinders ( 7 ) Means are provided by means of which the distance of the counter element ( 10 . 20 ) from the surface of the cylinder ( 7 ) by means of the gripper ( 6 ) guided printing sheet (B) in relation to the height of the gripper ( 6 ), wherein a transfer or stamping foil web ( 21 ) in front of the printing nip (S) for molding a structure or a glossy surface into a surface coating of the surface or for applying a transfer layer from a transfer film ( 5 ) on a surface coating as a cylinder ( 10 ) counterpart element is assigned, such that the cylinder ( 10 ) the transfer or stamping foil web ( 21 ) on the cylinder leading to the bow ( 7 ) laid on coated substrate (B) hangs up. characterized in that on the surface ( 16 ) or the surface elements of the sheet leading cylinder ( 7 ) at least in that of the or all of the counter elements ( 10 . 20 ) assigned to the diameter of the arc leading cylinder ( 7 ) changing support element ( 13 . 14 ) or that a sheet of leading cylinders ( 7 ) with a relative to a normal diameter ( 16 ) enlarged working diameter is provided and / or that the diameter of the sheet leading cylinder ( 7 ) in the area of the gripper ( 6 ) is reduced such that the surface ( 16 ) of the arc leading cylinder ( 7 ) and the height of the grippers ( 6 ) against counter elements ( 10 . 20 ) have an approximately equal level (F1, F2). Sheet-fed printing machine with a feeder, at least one printing unit or coating unit for printing or coating printed sheets (B), with a delivery arm, and with at least one processing unit integrated into the sheet-fed printing machine ( 1 ), the processing unit ( 1 ) one leading the printed sheets (B) and with grippers ( 6 ) provided cylinder ( 7 ), as well as a cylinder ( 7 ) associated counter element ( 10 . 20 ), wherein at or in connection with the one or more of the printing sheets (B) leading cylinders ( 7 ) Means are provided by means of which the distance of the counter element ( 10 . 20 ) from the surface of the cylinder ( 7 ) by means of the gripper ( 6 ) guided printing sheet (B) in relation to the height of the gripper ( 6 ), wherein a transfer or stamping foil web ( 21 ) in front of the printing nip (S) for molding a structure or a glossy surface into a surface coating of the surface as a cylinder ( 10 ) counterpart element is assigned, such that the cylinder ( 10 ) the transfer or stamping foil web ( 21 ) on the cylinder leading to the bow ( 7 ) guided coated substrate (B) hangs up, and that a film guide roller ( 23 ) on the circumference of the cylinder ( 7 ) is arranged spaced apart in the transport direction from the printing nip (S), so that over the film guide roller ( 23 ) the transfer or stamping foil web ( 21 ) from the connection to the printing material (B) on the cylinder ( 7 ) is characterized in that on the surface ( 16 ) or the surface elements of the sheet leading cylinder ( 7 ) at least in that of the or all of the counter elements ( 10 . 20 ) assigned to the diameter of the arc leading cylinder ( 7 ) changing support element ( 13 . 14 ) or that a sheet of leading cylinders ( 7 ) with a relative to a normal diameter ( 16 ) enlarged working diameter is provided and / or that the diameter of the sheet leading cylinder ( 7 ) in the area of the gripper ( 6 ) is reduced such that the surface ( 16 ) of the arc leading cylinder ( 7 ) and the height of the grippers ( 6 ) against counter elements ( 10 . 20 ) have an approximately equal level (F1, F2). Sheet-fed printing machine according to claim 2 or 3, characterized in that the effective surface ( 16 ) of the arc leading cylinder ( 7 ) in the region of the support of the transfer or stamping foil web ( 21 ) between the printing nip (S) and the film guide roller ( 23 ) on the surface of the cylinder ( 7 ) directed dryer ( 24 ) is arranged. Sheet-fed printing machine according to one of claims 1 to 4, characterized in that on the sheet leading cylinder ( 7 ) a working surface of the cylinder ( 7 ) forming building element ( 13 . 14 ) is provided, such that the resulting surface (R1, R2) outside the range of the gripper ( 6 ) approximately on the horizon ((F1, F2) of the grippers ( 6 ) including a printed sheet (B).

Images