EP3016804B1 - Production with clock system for cold film transfer - Google Patents

Description

The invention relates to a device for transferring imaging layers from a carrier foil to printed sheets according to the preamble of patent claim 1.

It is from the EP 0 569 520 B1 make known metallic layers on printed sheets by means of a film transfer process. It is shown a sheet processing machine with a coating module. In a first printing unit, an adhesive pattern is applied, for example, in a planographic printing process. In the following this printing unit coating module with a counter-pressure cylinder and a press roller, a film guide is provided, in which a transfer sheet from a film supply roll is guided through a transfer nip of the coating module and wound on the outlet side of the coating module. The transfer film is composed of a carrier layer, a release layer and an imaging transfer layer with metallic layers, such as aluminum.

From the DE 10 2009 026 438 A1 a device for cold foil stamping is known. In this device, the film feed in a coating module for the transfer of imaging layers of a transfer film to a printing material is to be extended in its applicability. For this purpose, a limited pressing surface is arranged in the coating module for transferring layers from the transfer film. For a targeted control of the film feed is possible. In this case, the transfer film is preferably guided past a press roll in a limited width and approximately tangentially. For film storage and film promotion special cyclically operable conveyors are assigned for this purpose

From the DE 10 2012 219 663 A1 is a clock drive for a film transfer device known. A film feed in a coating module for the transfer of imaging layers from a transfer film to a substrate should be extended in their applicability. This is in the coating module for transferring layers of the transfer film a limited pressing surface arranged. For a targeted control of the film feed is possible. In this case, the transfer film is preferably guided past a press roll in a limited width and approximately tangentially. For film promotion special cyclically operable conveyors are assigned for this purpose, wherein the conveyors are designed as drive groups, each with a film drive roller and a clock drive for the clocked supply / discharge of the transfer film at the transfer nip. For slip-free drive a non-contact pressing of the transfer film is provided to the film drive roller.

It is known to use such coating modules in printing units of sheet-fed printing machines, wherein the coating can be overprinted subsequent printing units. A disadvantage of the known devices is that they can not be used flexibly.

The object of the invention is therefore to provide a device by means of which the transfer of an imaging layer, e.g. a metallization layer, can be done economically and accurately on a sheet, the device should in particular allow a partial film application and should be significantly simplified in their handling.

The solution of this problem results in a device according to the features of claim 1.

The device provides a clock system for guiding the transfer film web. A tactile film drive in each case has a dynamically driven drive roller for cyclically moving a transfer film web.

According to the invention, the conveying device is arranged as a structural unit in the form of a clock unit on the coating module displaceable and lockable at least in a first and in a second position different from the first position. Advantageously, the clock unit can be locked on a guide device in a first position for carrying out the cold foil transfer.

According to the invention, the timing unit on the guide device in a second position for the execution of maintenance, the supply of transfer film web to prepare a production operation with cold foil transfer or for inactive positioning or for the execution of an operation of the cold foil transfer without clocking locked.

Advantageously, the clock unit can also be removed from the coating module.

Furthermore, according to the invention, the clock unit can be connected to the coating module at least via a first and / or via a further second film path through the transfer film web to the transfer nip.

Advantageously, a first film path leads from the clock unit via a downstream film guide roller directly to the surface of the press roller and then to the transfer nip of the coating module.

Advantageously, the film guide roller is mounted firmly in the coating module in connection with the timing unit or outside the timing unit. Here, a bearing point of a washing device is preferably used as a bearing.

Advantageously, a second film path without passing through the clock unit via a Folienleiteinrichtung, which may be formed by Folienleitwalzen, only at a short distance to the transfer nip to the surface of the press roll and then directly into the transfer nip of the coating module.

Advantageously, the clock unit in the coating module via film guide on a second film path with the transfer gap for the cold foil transfer in the simplified cycle operation can be connected.

Figur 1

den erfindungsgemäßen Aufbau einer Folientransfereinrichtung zur Folientaktung in einer Bogendruckmaschine und

Figuren 2 bis 3

den schematisch dargestellten Aufbau einer Takteinrichtung in Schnittdarstellung.

In the following the invention is illustrated in more detail by means of drawings. Showing:

FIG. 1

the inventive structure of a film transfer device for film timing in a sheetfed press and

FIGS. 2 to 3

the schematically illustrated construction of a clock device in a sectional view.

FIG. 1 shows a printing unit of a sheetfed offset printing machine, which contains several more - not shown here - printing units and is used for cold foil transfer. In this case, a printing sheet S is provided with an adhesive pattern in an offset printing unit upstream of the illustrated printing unit (applicator unit 1). In the illustrated offset printing unit (coating module 2), the printed sheet S is then fed with a transfer film 5 under pressure through a transfer nip 6, a transfer layer being transferred, for example, from metal. In further printing units (symbolized as printing unit D), the printed sheet S is then overprinted in color and optionally provided with a protective layer or gloss layer.

The applicator 1 is a known offset printing unit with inking, plate cylinder and blanket cylinder. The blanket cylinder interacts with an impression cylinder.
The coating module 2 is designed as an offset printing unit or possibly as a paint module of a sheetfed offset printing press, whose inking and dampening are out of function. The transfer nip 6 in the coating module 2 is formed by a press roll 3 and an impression cylinder 4. The press roll 3 is formed by the blanket cylinder of the offset printing unit or the forme cylinder of the lacquer module. With web guiding elements 14 in and on the coating module 2, the transfer film 5 is also switched on and executed by protective devices 15 of the coating module 2.
The coating module 2 is associated with a film supply roll 8, wherein for this purpose a roller drive 7 for the controlled feeding of the transfer film 5 is arranged. On the outlet side, the film module 2 for used sheet material is assigned a film collecting roller 9 (symbolized) with a roller drive.
The press roll 3 is provided with a press fabric 10, for example, as a plastic coating, comparable to a rubber or blanket.

The coating module 2 can be associated with dryers, such as UV dryers, for drying the adhesive or the entire film coating. By means of a monitoring device for scanning the sheet surface, the evaluation of image contents or detection of defects in the coating can take place. The web tension of the transfer film 5 can be monitored with measuring devices in conjunction with film guide devices 14 designed as film guide rollers. To stabilize the transfer film web 5, a stabilization device 30 with two guide rollers is used in front of the transfer nip 6.

Furthermore, as a surface of the press roll 3, a smooth or contoured or segmented press surface in the press fabric 10 should also be provided. For this purpose, segmented pressing areas limited to one or more areas to be coated are used on the press roller 3 in addition to a full-surface pressing area. By means of the limited segmented pressing surface in the press fabric 10, the transfer film 5 is pressed against a print sheet S on the impression cylinder 4 only when the segmented press surface passes through the transfer nip 6 and thereby effect a transfer of imaging layers from the transfer film 5 to the print sheet.
It is provided that a timing of the film feed of the transfer film 5 be carried out so that the transfer sheet 5 is substantially only moved when it is pressed against the sheet S on the impression cylinder 4. By contrast, the film feed is reduced or stopped when no contact pressure of the transfer film 5 to a sheet S occurs.

1. I. Die Taktung des Vorschubs der Transferfolie 5 kann beim Durchlauf von Zylinderkanälen 22 durch den Transferspalt 6 ausgeführt werden, es erfolgt also eine so genannte Kanaltaktung.
2. II. Die Taktung des Vorschubs der Transferfolie 5 kann ausgeführt werden, wenn ein durch an der Pressbespannung 10 begrenzte Pressflächen definiertes Druckformat zu einem Drucksujet für zu beschichtende Bereiche innerhalb des Druckbogens S vorliegt. Hierbei spricht man dann von einer Formattaktung oder Sujettaktung, die vorzugsweise kürzer als die maximale Länge des Druckformates ist.
3. III. Die Taktung des Vorschubs der Transferfolie 5 kann ausgeführt werden, wenn der durch segmentierte Pressflächen an der Pressbespannung 10 definierte zu beschichtende Bereich innerhalb des Bildbereiches des Druckbogens S liegt. Dann spricht man von einer Prägebereichstaktung, die sich auf einen Bereich innerhalb des Drucksujets bezieht.
4. IV. Eine weitere Verbesserung der Folienausnutzung der beschriebenen Art ergibt sich, wenn die Transferfolie 5 in eine oder mehrere Teilfolienbahnen geringerer Breite aufgeteilt wird. Die ist insbesondere in Verbindung mit der segmentierten Pressfläche von großem Vorteil.

Therefore, some effects can be achieved in a coating module 2 with a segmented pressing surface provided in a press fabric 10:

1. I. The timing of the feed of the transfer film 5 can be performed during the passage of cylinder channels 22 through the transfer nip 6, so there is a so-called channel timing.
2. II. The timing of the feed of the transfer film 5 can be carried out when a defined by the press fabric 10 limited pressing surfaces printing format to a printed matter for areas to be coated within of the printing sheet S is present. This is then called a formattaktung or Sujettaktung, which is preferably shorter than the maximum length of the print format.
3. III. The timing of the feed of the transfer film 5 can be carried out when the area to be coated defined by segmented pressing surfaces on the press fabric 10 lies within the image area of the print sheet S. Then one speaks of a Prägebereichpaktung, which refers to an area within the Drucksujets.
4. IV. A further improvement of the film utilization of the type described results when the transfer film 5 is divided into one or more Teilfolienbahnen lesser width. This is particularly advantageous in connection with the segmented pressing surface.

For film supply and film removal of the drive of the film rolls 8, 9 takes place continuously. In the cycle operation of the cold foil transfer thus fall when braking the transfer film web 5 at the end or after the end of the transfer area to re-accelerate at the beginning or before the beginning of the transfer area in the supply and Abführbereichen the transfer film web 5 relative to the movement of the film rolls 8, 9 excess or missing film lengths.

FIG. 1 shows an arrangement for rapid compensation of displacements of the transfer film web 5 in the feed area and in the discharge area in the film timing in the cold foil transfer process. For clocked promotion of the transfer film 5 drive groups 33 and 37 are provided which consist of roller assemblies in conjunction with drives. The transfer film 5 is conveyed via friction by the drive groups 33, 37. In this case, at least the drive group 33 assigned to the transfer film web 5 in front of the transfer nip 6 must be able to convey the transfer film 5 without slip to the transfer nip 6.

The required storage effect in the film timing is generated by using a per se known principle of looping the transfer film web 5 by negative pressure. Here are film storage 32.1 and 32.2 in the form of unilaterally open and rectangular in cross-section vacuum chambers of Transfer film web guide assigned in the coating module 2. The height extent of the film storage 32.1, 32.2 specifies the size of a maximum possible film loop 36. The film loop 36 is fed to the respective film store 32.1, 32.2 through an open side of the vacuum chambers. At least one pneumatic system for generating negative pressure as a vacuum unit 32.3 is assigned to each open end side of the vacuum chambers. The vacuum unit 32.3 can be designed as a common aggregate for the vacuum chambers of both film stores 32.1, 32.2. The vacuum unit 32.3 may be constructed from one or more fans and is attached to the front side to be designated in terms of the pressure gradient as the bottom side or the one with respect to the working arrangement of the film reservoirs 32.1, 32.2 as the upper side of the vacuum chambers.

• Durch Absaugen von Luft mittels des Unterdruckaggregates 32.3 der Folienspeicher 32.1 und 32.2 wird jeweils eine Folienschlaufe 36 mit einer gemäß dem Verhältnis zwischen der sich aus dem erzeugten Unterdruck und dem Spannung der Transferfolienbahn 5 einstellenden Kraft in jede der Unterdruckkammern der Folienspeicher 32.1 und 32.2 hineingezogen. Diese die Folienschlaufe 36 bildende und haltende Kraft überwiegt nicht die von der Bahnspannungsregelung vorgegebene Zugkraft der Transferfolienbahn 5, da die Folienschlaufen 36 sonst in der Unterdruckkammern festgesaugt und damit blockiert würden. Das System ist insofern selbstregulierend als die Folienschlaufen 36 gegen die Kraft des Unterdrucks frei in den Unterdruckkammern pendeln können und so jeweils Teillängen der Transferfolienbahn 5 aufnehmen oder freigeben.

The effect of the film stores 32.1 and 32.2 is as follows:

• By sucking air by means of the vacuum unit 32.3 of the film storage 32.1 and 32.2, a film loop 36 is drawn in each of the vacuum chambers of the film storage 32.1 and 32.2 in accordance with the ratio between the resulting from the negative pressure generated and the voltage of the transfer film web 5 force. This forming the film loop 36 and holding force does not exceed the predetermined by the web tension control tensile force of the transfer film web 5, since the film loops 36 would otherwise be firmly sucked in the vacuum chambers and thus blocked. The system is self-regulating insofar as the film loops 36 can oscillate freely against the force of the negative pressure in the vacuum chambers and thus absorb or release partial lengths of the transfer film web 5.

For controlling the film web conveyance, the size of the film loops 36 within each film store 32.1 and 32.2 is detected by means of a sensor system which is based for example on a distance measurement by means of ultrasound. It is thus recognized how far the film loop 36 is pulled into the respective vacuum chamber. On the basis of these constantly recorded measurement signals, the film web feed for the film feed and the film removal can then be regulated by means of the drives of the film rolls 7, 8 and possibly in conjunction with dancer rolls 18.

In order to maintain the web tension of the transfer film web 5 and to ensure its perfect guidance, the generated negative pressure of the vacuum unit 32.3 in the film stores 32.1, 32.2 can furthermore be regulated. Thus, the process-dependent required formation of the film loops 36 is ensured at all times to a sufficient extent.

1. a) Bei Unterbrechung des Folientransfers und dem Stillsetzen des Folientransportes im Transferbereich (Transferspalt 6) wird durch Stillsetzen der Antriebsgruppe 33 vor dem Transferspalt 6 bei weiterlaufender Folienvorratsrolle 8 eine auflaufende Folienbahnlänge freigegeben, die mittels Unterdruck in den ersten Folienspeicher 32.1 hineingezogen wird.
2. b) Auf der Ablaufseite nach dem Transferbereich (Transferspalt 6) wird gleichzeitig bei stillstehendem Folientransport die Transferfolienbahn 5 aus dem zweiten Folienspeicher 32.2 gegen den dort herrschenden Unterdruck zur kontinuierlichen Aufwicklung auf der Foliensammelrolle 9 freigegeben.
3. c) Zum Fortsetzen des Folientransfers und damit dem erneuten Einsetzen des Folientransportes im Transferbereich (Transferspalt 6) wird die Antriebsgruppe 33 wieder aktiviert und die eingezogene Folienschlaufe 36 wird aus dem ersten Folienspeicher 32.1 gegen den dort herrschenden Unterdruck wieder dem Transferbereich zugeführt.
4. d) Gleichzeitig wird der zweite Folienspeicher 32.2 von einer Antriebsgruppe 37 wieder mit einer Folienschlaufe 36 befüllt, da der Folienabzug aus dem Folienspeicher 32.2 mittels der Foliensammelrolle 9 langsamer abläuft als die Folienzufuhr mittels der Antriebsgruppe 37.

The arrangement of the film stores 32.1, 32.2 serves to allow the timing of the film web advance when stopping and continuing the film transport by means of the drive groups 33, 37 in the transfer area to be carried out as follows:

1. a) When interrupting the film transfer and stopping the film transport in the transfer area (transfer nip 6) is released by stopping the drive group 33 before the transfer nip 6 with ongoing film supply roll 8 a length of film web length, which is drawn by means of negative pressure in the first film memory 32.1.
2. b) On the discharge side after the transfer area (transfer nip 6), the transfer film web 5 is released from the second film store 32.2 against the prevailing negative pressure for continuous reeling on the film collecting reel 9 at the same time when the film transport is stationary.
3. c) To continue the film transfer and thus the re-insertion of the film transport in the transfer area (transfer nip 6), the drive group 33 is activated again and the retracted film loop 36 is fed from the first film memory 32.1 against the prevailing negative pressure back to the transfer area.
4. d) At the same time, the second film store 32.2 is again filled with a film loop 36 by a drive group 37, since the film removal from the film store 32.2 by means of the film collection roller 9 proceeds more slowly than the film feed by means of the drive group 37.

In FIG. 1 the film stores 32.1 and 32.2 are shown in the coating module 2 according to the illustrated functions. The film stores 32.1 and 32.2 are approximately perpendicular adjacent to the film supply roll 8 parallel to each other arranged. A first drive group 33 is arranged with two film guide rollers 35, a drive roller 34 and a pressure roller 40 on the inlet side of the transfer area close to the transfer nip 6. Another drive group 37 with two film guide rollers 39 and a drive roller 38 is upstream of the film storage 32.2 on the discharge side from the transfer nip 6 ago. This arrangement makes the feeding of the transfer film web 5 from the film loop 36 in the film store 32.1 compact and allows the smoothing and stabilizing device 30 a secure feed of the transfer film web 5 to the first drive group 33. Furthermore, the transfer film web 5 on the outlet side of the transfer area after the transfer nip be guided smoothly over the transfer film web 5 Folienleitelemente approximately in the form of Folienleitwalzen 14 or in the manner of a smoothing and stabilizing device.

On the feed side and the discharge side of the film storage 32.1 and on the discharge side of the film storage 32.2 a film guide roller 31 is shown, which serve for better management of the transfer film web 5, so that the transfer film web the film storage 32.1 exactly fed and kept smooth from the film storage 32.2 for winding is dissipated.

The vacuum chambers of the film storage 32.1 and 32.2 can be designed according to the width of leading film or partial film webs, being provided in the direction of the film loops 36 parallel to the side edges aligned and slidably disposed in the width direction separating devices. If the vacuum chambers have the width of a transfer film web and are displaceable, it is possible to respond flexibly to desired coating conditions. Furthermore, in the maximum width of the working area completely overlapping vacuum chambers, the above-mentioned separating devices may be arranged, each of which limit the lateral position of the transfer film web 5 or partial film webs. Thus, the film storage 32.1 and 32.2 can be divided advantageously into several parallel vacuum chambers of variable width and function. These can be tuned to individual transfer film webs 5 of different widths or to partial film webs of the same or different widths. Preferably, to maintain the Underpressure in unneeded areas, the lower of the sheet feeder associated end face or the upper portion of the vacuum unit 32.3 designed closable.

In FIG. 2 one of the aforementioned drive groups 37 is shown in a first technical embodiment for the withdrawal of the transfer film web 5 from the working area in the transfer nip 6. This workgroup 37 is in accordance with a section U in FIG. 1 upstream of the film storage 32.2. In the drive group 37, a film drive roller 70 is coupled within a housing 72 with a clock drive 71, which controls the movement of the film drive roller 70 highly dynamically. The film drive roller 70 shown here corresponds in FIG. 2 the drive roller 38 (see section U in Fig. 1 ).
The film drive roller 70 is in the illustrated embodiment a plurality of groups or evenly distributed in the axial direction of the film drive roller 70 and freely rotatably mounted on an axis rotatably mounted pinch rollers 24 assigned. The pinch rollers 24 are connected to a pivotable and revolving panel element 73 of the drive group. Thereupon, the pressure rollers 24 can be pivoted from the film drive roller 70 for the introduction of the transfer film web 5 and then swung back again. The setting of the position of the elastic pressure rollers 24 is selected in the working position so that the inserted transfer film is pressed against the film drive roller 70 without deforming or damaging them. In addition, this is chosen so that the inserted transfer film 5 is pressed against the film drive roller 70, so that the transfer film 5 can be conveyed with or without slippage through the conveying nip.
The transfer film 5 is fed to and removed from the film drive roller 70 via film guide rollers 23, so that a wrap of more than 90 degrees is formed. A wrap of the transfer film 5 of about 180 degrees or more on the film drive roller 70 is advantageous. This ensures good film guidance and additional friction surface for secure film transport.
The drive group 37 is designed so that the transfer film 5 in a film strand of the film feed 5A from a film memory (32.1, see Fig. 1 ) supplied to the transfer nip 6 and further from the transfer nip 6 a further film storage (32.2, see Fig. 1 ) can be supplied. This type of film web guide is dependent on the respective arrangement of the elements to each other, the solution shown is based on that the film memory 32.1, 32.2 are arranged parallel to each other and directly coupled to each other. This creates a very easy to handle film guide in an extremely compact design.

When said drive group 37 after FIG. 2 as in FIG. 1 shown used as a second drive group for the removal of the expiring film strand of the film removal 5B of the transfer film web 5 from the transfer nip 6 to the film storage 32.2 after the transfer nip 6, the drive motor of the film drive roller 70 may also be set as continuously running. Then, the drive group 37 continuously pulls the transfer film web to ensure a continuous film removal of the used transfer film 5 to the film collecting roller 9. On the other hand, in the cycle mode, the foil conveyance is interrupted when the transfer ribbon web is stationary and the drive group 37 then runs in slipping operation with respect to the outgoing foil strand 5B. Therefore, in the aforementioned case, a larger looping of the film drive roller 70 through the film strand of the film removal 5B of the transfer film web 5 is not required or rather a hindrance, since only a minimum web tension for removal still maintained otherwise slippage must be allowed.

The compact design of the drive group 37 in the housing 72 is further improved in an assignment to the first film memory 32.1 that in the same housing 72 and a Folienleitwalze 23.1 for discharging the transfer film web 5 in a Zuführstrang the film feeder 5A from the first film memory 32.1 for feeding Direction to the transfer nip 6 is arranged.
For this purpose, the drive group 37, as well as in FIG. 2 is shown, arranged in the immediate vicinity of the open end faces of the film storage 32.1, 32.2. The film guide roller 23.1 corresponds to the film guide roller 31, which is the drive group 37 and the film guide roller 39 next.

In FIG. 3 is a further drive group for the functionality of the supply of the supplied film strand of the film feeder 5A according to the drive group 33 in FIG. 2 shown in a second technical embodiment.
Therein a film drive roller 70 is coupled to a clock motor 71 which controls the movement of the film drive roller 70 in any movement cycles highly dynamically. The film drive roller 70 is assigned a freely rotatably mounted pressure roller 40 with preferably smooth elastic surface. The pressure roller 40 is coupled to a swiveling and revolving panel element 73 of the drive group. Thus, the pressure roller 25 can be pivoted directly or indirectly via a Getriebeanlenkung during pivoting of the lining element 73 of the film drive roller 70 for the introduction of the transfer film web 5 and then swung back. The position of the pressure roller 40 is selected in the working position so that the inserted transfer film 5 is pressed against the film drive roller 70 without deforming or damaging them. In addition, this is chosen so that the inserted transfer film 5 is pressed against the film drive roller 70, so that the transfer film 5 can be promoted as possible slip.
The transfer film 5 is fed in this embodiment of the film drive roller 70 via a film guide roller 23 and discharged via the pressure roller 40 and another film guide roller 25 again, so that a wrap of more than 90 degrees. Advantageously, a looping of the transfer film web 5 on the film drive roller 70 of about 180 degrees or more, as shown in the aforementioned embodiment of FIG. 4. This ensures good film guidance and additional friction surface for safe film transport.

To FIG. 1 a clock unit in the form of a drive group 33, consisting of a drive roller 70, a clock drive 71, Folienleitwalzen 35 and a pressure roller 40 is arranged displaceably in front of the transfer nip 6. For this purpose, a guide for the clock unit 33 is arranged on or between the frame walls of the respective printing unit or lacquer module used as a coating module 2. For this purpose, the clock unit / drive group 33 is movably arranged by means of guides (round / flat or dovetail guides) and locked in at least two end positions E1 and E2.

E1:

Position der Produktionsstellung und

E2:

Position der Park- oder Wartungsstellung zum Folieneinzug oder Folienwechsel oder im reinen Druckbetrieb bei abgewähltem Folientransferbetrieb. E2 ist auch Entnahmeposition der gesamten Einheit per Hand oder mit einem Hebezeug. Die Wechselpositionen (Pos. 1-n) können werkzeuglos erreicht werden und auch die Entnahme der Einheit erfolgt bevorzugt werkzeuglos.

The end positions E1 and E2 are to be characterized as follows:

E1:

Position of production position and

E2:

Position of the parking or maintenance position for film feed or film change or in pure printing mode with unselected film transfer operation. E2 is also removal position of the entire unit by hand or with a hoist. The change positions (pos. 1-n) can be achieved without tools and also the removal of the unit preferably takes place without tools.

Plug connections for the electrical supply of the drive group 33 and possibly also cooling lines for drive cooling of the clock motor 71 are provided in a simple manner and are arranged as quick couplings on a plug unit assigned to the clock unit 33 in the form of a quick change system.

The pressure roller 40 in the film transport direction downstream Folienleitwalze 25, 35 may be associated with the clock unit / drive group 33 and may be attached to the housing 72 of the clock unit 33. Said film guide roller 35 can be taken as the last guide element for the film guide in front of the transfer nip 6 but also preferably in a frame-mounted holder for receiving a blanket washing device.

The clock unit 33 is after FIG. 1 and FIG. 3 designed as a unit with a housing 72 in cassette form. For film feed, the roll distances within the housing 72 are adjustable relative to the working position during operation for cold foil transfer, so that a larger intake gap results. By means of the cladding lid on the clock unit 33 running lining element 73, the interior of the clock unit can be made accessible.

The entire clock unit 33 can not only displaceable (horizontal, vertical, oblique) but also in other design versions additionally or exclusively via a pivot point (displaceable) hinged or by means of linkage generate a superimposed translational and rotary movement to bring the clock unit 33 from the working position E1 near the transfer nip 6 in a remote from the machine frame position E2 for film feed.

The entire clock unit 33 incl. Folienleitwalzen 25, 35 and guides for moving is preferably covered by protective devices such as something a folding step on the printing unit or coating module 2 for safety reasons.

As a rule, a simple longitudinal guide, which is accommodated on the A and B sides of the machine frame, is sufficient for displacing the clock unit 33 from the working position E1 into the film changing position E2, ie in the direction of a sheet feeder upstream of the printing unit. For this purpose, the clock unit 33 has ergonomically designed manipulation aids, which simultaneously serve to change and remove the clock unit 33, e.g. for maintenance purposes, as well as possibly serve as a receiving adapter for lifting equipment.

The guide elements for receiving the clock unit e.g. Shafts of a longitudinal guide unit are generally mounted fixed to the frame and can also be mounted in preparation for a plurality of printing units (paint module) of a machine in order to use a clock unit in a cold foil device at a plurality of application sites. in a second printing unit or a lacquer module. Thus, the clock unit can be flexibly used at several change positions.

The clock unit 33 can also be changed from a sheet-fed offset printing press to another sheetfed offset printing press within a printing operation, since this is an independent structural unit.

For better accessibility during film feed the machine-side protection device in front of the inking unit or coating unit of each used as a coating module 2 printing unit or paint module can be raised or pivoted to to press roll 3 (blanket cylinder, paint form cylinder) to achieve more space and better accessibility.

According to the invention, in the context of the film guide in the coating module 2 according to FIG FIG. 1 between the clock unit 33 and the transfer nip 6 two different film paths F1 and F2 described depending on operation and coating quality.

In this case, in the case of the film path F1, a larger looping of the press roll 3 through the transfer film web 5 is achieved. It has been found that for a clocked running operation in the implementation of the cold foil transfer, an increase in the coating quality can be achieved if a larger looping is set at the press roller 3.

Therefore, in the clocked version of the cold foil transfer, the clock unit is moved with the drive group 33 in the first locking position E1, wherein the transfer film web 5 is fed in the film guide of the film guide roller 35 from the transfer nip 6. Since the film guide roller 35 is arranged in connection with the timing unit, the guide of the transfer film web 5 of the surface of the press roller 3 is already supplied at such a distance in front of the transfer nip 6 that results in a comparison with a nearly tangential guide increased wrap and thus improved leadership. In this case, it is important that the surface of the press roll 3 has a reduced friction with respect to the transfer film 5 or the rear side of the transfer film 5 resting on the press roll 3 and forming a carrier film.

Furthermore, in the case of the film path F2, a lower wrap of the press roll 3 is achieved by the transfer film web 5, wherein the film guide is formed on the press roll 3 until it is approximately tangential. It has been found that for a running without clocking operation in the implementation of the cold foil transfer a simpler way of production sufficient coating quality is achieved when a lower wrap is set at the press roller 3.

For this reason, the slidable arrangement of the timing unit with the drive group 33 is not used only for the convenience of inserting the transfer sheet 5. According to the invention the clock unit for the simplified operation of the cold foil transfer without clocking is also spent in the second locking position E2. The transfer film 5 can then be guided past the clock unit and fed to the transfer nip 6 via film guide rollers of a film guiding device 14, in which case a more tangential guidance of the transfer film 5 takes place on the press roller 3 through the transfer nip.

Furthermore, the film guide for a simplified operation of the cold foil transfer after FIG. 1 also be guided by the timing unit 33 on a film path F3 similar to the second film path F2 via one or more film guide rollers of a film guide device 14. In this case, the transfer film web 5 according to FIG. 1 coming from the clock unit 33 via the film guide roller 35 to one or more of the film guide rollers of the film guide 14 out. In this way, a virtually tangential guidance of the transfer film web 5 on the press roller 3 through the transfer nip 6 is also made possible for the operation with clocked cold foil transfer.
Such a mode of operation is advantageous when the film timing is carried out with the execution of smaller clock steps and resulting downtime of the transfer film web 5. By means of such an operation, larger machine speeds and thus increased product output can be achieved.

LIST OF REFERENCE NUMBERS

1

commissioned

2

coating module

3

press roll

4

Impression cylinder

5

Transfer film / transfer film web

5A

film feed

5B

foil transfer

6

transfer nip

7

roller drive

8th

Film supply roll

9

Foil composite role

10

Press covering

13

Blanket cylinder

14

Folienleiteinrichtung

15

guard

22

cylinder gap

23

Folienleitwalze

23.1

Folienleitwalze

24

pinch

25

pressure roller

26

Andrucksegment

26.1

inner guide surface

27

holder

28

blow air

29

pressure device

30

stabilizing device

31

Foil guide roller / foil feed

32.1

film storage

32.2

film storage

32.3

Vacuum unit Foil storage

33

Drive group / clock unit

34

drive roller

35

Folienleitwalze

36

Loop / foil loop

37

drive group

38

drive roller

39

Folienleitwalze

40

pressure roller

70

Film drive roller

71

stroke engine

72

casing

73

Cladding, cladding element

E1

first locking position

E2

second locking position

F1

first film path

F2

second film path

F3

third film path

G

Cutting drive unit 37

R

transport direction

S

sheet

Claims (11)

1. A device of a sheet processing machine for the cold film transfer to printing sheets comprising at least one applicator (1) for a pictorial coating of the printing sheets with an adhesive and comprising a coating module (2) for transferring the transfer layers to the printed sheet in a transfer gap (6) between an impression cylinder (4) and a press roller (3), and comprising a mechanism for feeding the transfer film (5) to the coating module (2) and for discharging from the coating module (2) comprising a drive for moving the transfer film in operating direction, wherein the film feed of the transfer film (5) can be controlled in such a way by means of a mechanism for film feeding that the transport of the transfer film (5) is stopped, when a transfer of a transfer layer to a printed sheet does not take place in the transfer gap (6) of the coating module (2),
   wherein controllable conveyors (33, 37) for braking and accelerating so as to be timed to the processing cycle of the cold film transfer are assigned to the transfer film (5), wherein the conveyors (33, 37) are embodied as roller arrangements, which guide and drive the transfer film web (5) in a clamping manner, and wherein at least one conveyor (33, 37) is assigned to a transfer area upstream of the transfer gap (6),
   characterized in
   that the conveyor, as structural unit in the form of a timing unit (33) upstream of the transfer gap (6) in a displaceable manner on the coating module (2) at least via a first film path (F1), in the case of which the guide of the transfer film web (5) is guided to the surface of press roller (3) upstream of the transfer gap (6), so that an enlacement, which is enlarged as compared to a virtually tangential guide, results on the press roller (3), and is arranged so as to be capable of being connected by means of the transfer film web (5) on the way to the transfer gap (2) of the coating module (2) via a second film path (F2), which differs from the first film path (F1), in the case of which a virtually tangential guide of the transfer film web (5) takes place on the press roller (3) through the transfer gap (6).
2. The device according to claim 1,
   characterized in
   that the timing unit (33) in the coating module (2) can be connected so as to be timed via a film guide roller (23; 25; 35) across the first film path (F1) for carrying out the coating process after the cold film transfer.
3. The device according to claim 2,
   characterized in
   that the film guide roller (23; 25; 35) is supported in the coating module (2) in connection with the timing unit (33).
4. The device according to claim 2,
   characterized in
   that the film guide roller (23; 25; 35) is fixedly supported in the coating module (2) outside of the timing unit (33), wherein a bearing point of a washing device preferably serves as bearing point for the film guide roller (25, 35).
5. The device according to one or a plurality of claims 1 to 4,
   characterized in
   that the timing unit (33) in the coating module (2) can be connected via film guide elements (14) across a second film path (F2) for carrying out the coating process after the cold film transfer in a simplified cyclic operation.
6. The device according to one or a plurality of claims 1 to 5,
   characterized in
   that the film guide in the coating module (2) is carried out via film guide elements (14) across a second film path (F2) for carrying out the coating process after the cold film transfer without cyclic operation and without contact of the transfer film web (5) to the timing unit (33).
7. The device according to one or a plurality of claims 1 to 4,
   characterized in
   that the film guide in the coating module (2) is carried out via film guide elements (14) across a third film path (F3) for carrying out the coating process after the cold film transfer with or without turning on a cyclic operation and with guiding the transfer film web (5) through the timing unit (33).
8. The device according to one or a plurality of claims 1 to 4,
   characterized in that the conveyor as structural unit in the form of a timing unit (33) is arranged in a displaceable and lockable manner on the coating module (2) at least in a first position (E1) and in a second position (E2), which differs from the first position (E1).
9. The device according to claim 8,
   characterized in
   that the timing unit (33) in the coating module (2) can be locked on a guide device in a first position (E1) for carrying out the coating process after the cold film transfer.
10. The device according to claim 8 or 9,
    characterized in
    that the timing unit (33) in the coating module (2) can be locked on a guide device in a second position (E2) for carrying out maintenance operations or the feeding of a transfer film web (5) for preparing a production operation with cold film transfer or for the inactive positioning for an operation of the sheet processing machine without cold film transfer.
11. The device according to one or a plurality of claims 8 to 10,
    characterized in
    that the timing unit (33) in the coating module (2) is movably supported on a guide device and is arranged so as to be capable of being removed form the guide device.

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