EP1537995B1 - Method for lateral aligning of sheets - Google Patents

Description

The invention relates to a method for aligning sheets after the side edge, in which the sheets to be aligned are conveyed within a scattering area on a feed table on which the actual position of the side edge determined by a measuring device and the respective foremost sheet detected by a Bogenbeschleunigungsvorrichtung and the Gripper system is fed to a drum, wherein the gripper system for the realization of the desired position of the side edge, which, objectified by an approximately centrally provided in the scattering range side draw line, can be moved in the axial direction.

From the DE 36 44 431 A1 It is known to align sheets to the side edge on a drum by axial displacement of the gripper system. The sheets separated by a sheet feeder are transported on the feed table so that the side edges run in within a scattering area. The actual position of the side edge is detected by a measuring device and compared with a desired position. In this case, the desired position is identical to a so-called side draw line, which is provided approximately centrally in the scattering area. In the event of deviations of the actual position from the desired position, an actuating signal is generated by the measuring device and supplied to an actuating device which displaces the gripper system of the drum downstream of a sheet accelerating device in the axial direction. A sheet transported by the sheet accelerating device from the feed table to the gripper system of the drum is brought into the desired position by axial displacement of the gripper system with respect to the side edge and then transferred to the gripper device of a downstream cylinder.
There is a risk that the gripper system and the gripping device come too close to the sheet transfer in large drawing paths, so that it comes in the processing of thick substrates to impermissible bow deformations. In order to eliminate these disadvantages, it is known to design the gripper loads of the gripper system of the drum height adjustable, which requires a lot of effort. Another way to eliminate these disadvantages is to make the distances between the grippers of the gripper system and the grippers of the gripping device large and the width of the gripper low. However, this requires a poor bowing, which leads to an increased spoilage and business interruptions.

To eliminate these disadvantages, is in the DE 102 16 758 A1 proposed to move the gripper system of the drum for aligning the sheet to the side edge and after passing the sheet to the downstream cylinder, the gripper system not due to a starting position (center position), but after detection the position of the following arc to spend the gripper system in the opposite direction to the half to be realized pulling path. As a result, an unacceptable bow deformation is avoided by laterally too close Asked gripper cuffs.

The disadvantage of this method is that, due to the machine geometry, the measured value characterizing the lateral position of the following sheet is present only shortly before the next sheet is taken over by the gripper system. This requires high accelerations or drive torques of the gripper system displacing actuators, in particular in high-speed machines, on the other hand, the gripper system remains after the transfer of the aligned sheet to the downstream cylinder to the transfer to the takeover position over a large machine angle.
The object of the invention is to provide a generic method for aligning sheets, which can be realized with little effort, even in high-speed machines.

According to the invention the object is achieved by a method according to the features of claim 1.

The inventive solution, it is possible to make the distances of the intermeshing sheet holding system so that without height adjustment of sheet holding systems, a sheet guide can be realized, which ensures trouble-free sheet even with troublesome substrates, where it by dividing the axial adjusting movement of the gripper system in three Partial movements is possible to reduce the accelerations and moments of the gripper system shifting actuator and so the method can also be applied to high-speed machines.

Fig. 1

eine Bogenanlage in der Seitenansicht,

Fig. 2

eine schematische Darstellung eines Anlegtischs in der Draufsicht,

Fig. 3

eine Gegenüberstellung der Schemata von ineinandergreifenden Bogenhaltesystemen.

In one embodiment, the invention is explained in detail. In the accompanying drawings show

Fig. 1

a bow plant in the side view,

Fig. 2

a schematic representation of a feed table in plan view,

Fig. 3

a comparison of the schemes of interlocking sheet holding systems.

in Richtung auf die Seite I oder die Seite II verschoben werden. In der Figur 3b ist dargestellt, dass das Greifersystem 6 in Richtung auf die Seite II verschoben wird. Nach Realisierung eines maximalen Ziehweges $\frac{Z}{2}$

wird das von dem Greifersystem 6 gehaltene bogenförmige Verarbeitungsgut an die Greifeinrichtung 8 übergeben und nachfolgend das Greifersystem 6 in seine Ausgangsposition (Mittenposition X) zurückgeführt. Um bei der Realisierung eines maximalen Ziehweges $\frac{Z}{2}$

in Richtung der Seite I oder II einen Systemabstand c gewährleisten zu können, ist die Breite a der Greiferfinger 10, der Greifer 14 und der Bogengreifer 12 um den maximalen Ziehweg $\frac{Z}{2}$

verringert und so der Abstand b um $\frac{Z}{2}$

vergrößert.In FIG. 1 is a sheet system, consisting of a feed table 1 with located in a position on the feed table 1 front marks 2, a sheet acceleration device 3, the is designed as a vibration system 4, a drum 5 with a gripper system 6 and a drum 5 downstream cylinder 7, which is equipped with a gripping device 8, shown. The oscillating system 4 has a vibrating gripper system 9, which consists of gripper fingers 10 and a gripper bar 11, wherein the vibrating gripper system 9 is associated frame-fixed the vibrating system 4. The gripper system 6 of the drum 5 is provided in the axial direction displaceable in the drum 5 and consists of grippers 14, which cooperate with gripper clutches 15. The cylinder 7 associated gripping device 8, which consists of sheet grippers 12 and gripper pads 13 is fixed to the frame mounted in the cylinder 7.
In FIG. 2 the feed table 1 is shown with a bow 16 and a follower bow 17. From the feed table 1 only in the sheet conveying direction 18 on the left side - one side I - located half is shown. On the opposite side there is a page II. The sheets 16,17 are transported in the sheet conveying direction 18 on the feed table 1. In a recess 19 of the feed table 1, which extends transversely to the sheet conveying direction 18 over at least one format adjustment area 20, a measuring device 21 is slidably and lockably provided. The measuring device 21 can be moved within the format range 20 and adjusted to the formats reaching for processing. The measuring device 21 extends at least over a scattering area 22 and is connected to an evaluation unit, not shown. The scattering area 22 is the area in which the side edges of the sheets reaching the processing can run in, so that their actual position can still be reliably detected and brought into a desired position. In this case, the desired position is identical to the position of a side draw line 23, which is provided approximately centrally in the scattering region 22.
In FIG. 3 different schemes of interlocking sheet holding systems are contrasted. The FIG. 3a shows the swing gripper system 9, the gripper system 6 of the downstream drum 5 and the gripping device 8 of the cylinder 7. The gripper system 6 of the drum 5 performs an axial movement for aligning to the side edge. The gripper fingers 10, gripper 14 and sheet gripper 12 have a width a, while between the gripper fingers 10, the grippers 14 or the sheet grippers 12, a distance b is provided. Between two interengaging sheet holding systems 9,6,8 a system distance c is provided. In this case, the system distance c is chosen so that the resulting during the transfer / acquisition deformations of the material to be processed are so small that the productivity of the printing press is not adversely affected. In the acquisition / transfer of the bow, the gripper fingers 10 / gripper 14 and gripper 14 / sheet gripper 12 are arranged centrally to each other.
FIG. 3b shows the state of the art, in which the gripper system 6 of the drum 5 is axially displaced to the processing material reaching arcuate to be able to align with one side edge. The grippers 14 of the gripper system 6 are arranged in the sheet transfer centered on the gripper fingers 10 of the vibratory gripper system 9 and can subsequently from its center position X a maximum of a pulling path $\frac{Z}{}$$\frac{}{2}$

in the direction of page I or page II. In the FIG. 3b It is shown that the gripper system 6 is moved in the direction of the side II. After realization of a maximum pulling distance $\frac{Z}{}$$\frac{}{2}$

the arcuate processing material held by the gripper system 6 is transferred to the gripping device 8 and subsequently the gripper system 6 is returned to its starting position (middle position X). In order to realize a maximum pulling distance $\frac{Z}{}$$\frac{}{2}$

in the direction of the side I or II to be able to ensure a system distance c, the width a of the gripper fingers 10, the gripper 14 and the sheet gripper 12 to the maximum pulling distance $\frac{Z}{}$$\frac{}{2}$

decreases and so does the distance b around $\frac{\mathrm{<figure-callout\; id="2"\; label="Z"\; filenames="imgf0001.png,imgf0002.png"\; state="\{\{state\}\}">Z</figure-callout>}}{2}$

increased.

eingehalten wird, jedoch bildet sich zwischen den ineinandergreifenden Greifern 14 und Bogengreifern 12 ein Bereich c + Z, in dem eine Bogenführung fehlt. Damit ist es möglich, dass innerhalb diesen Bereiches c + Z eine Bogenecke nicht geführt wird, so dass es zu Beeinträchtigungen des Bogenlaufs und damit zu Betriebsstörungen kommt.Although this ensures that the system distance c between the gripper system 6 and the gripping device 8 in the realization of a pulling path $\frac{Z}{}$$\frac{}{2}$

is maintained, however, forms between the intermeshing grippers 14 and sheet grippers 12 a range c + Z, in which a bow guide is missing. Thus it is possible that within this area c + Z a corner of the sheet is not performed, so that it comes to impairing the sheet travel and thus to malfunction.

ausgeführt. Damit wird der Abstand b um $\frac{Z}{4}$

vergrößert, so dass ein Systemabstand c eingehalten wird bei einem Bereich $\mathrm{c}+\frac{Z}{2}$

· Um aber einen maximalen Ziehweg $\frac{Z}{2}$

in Richtung der Seite I oder Seite II realisieren zu können, wird wie folgt verfahren.This disadvantage is in an embodiment after Fig. 3c eliminated. In this embodiment, the gripper fingers 10, gripper 14 and sheet gripper 12 in a width a - $\frac{\mathrm{<figure-callout\; id="4"\; label="Z"\; filenames="imgf0001.png,imgf0003.png"\; state="\{\{state\}\}">Z</figure-callout>}}{4}$

executed. This will change the distance b $\frac{Z}{}$$\frac{}{4}$

increased, so that a system distance c is maintained at a range $\mathrm{c}+\frac{\mathrm{<figure-callout\; id="2"\; label="Z"\; filenames="imgf0001.png,imgf0002.png"\; state="\{\{state\}\}">Z</figure-callout>}}{2}$

· But for a maximum pulling distance $\frac{Z}{}$$\frac{}{2}$

in the direction of the side I or side II, the procedure is as follows.

von der Seite I wegbewegt werden muss, um bezüglich der Seitenkante die Soll-Lage und damit die Seitenziehlinie 23 zu erreichen, werden die Greifer 14 des Greifersystems 6 um die Hälfte des zu realisierenden Ziehweges $\frac{Z}{2}$

, also um $\frac{Z}{4}$

in Richtung der Seite I bewegt. Danach wird der bogenförmige Bedruckstoff von den Greifern 14 des Greifersystems 6 geklemmt und nachfolgend das Greifersystem 6 um $\frac{Z}{2}$

von der Seite I wegbewegt und so die Soll-Lage realisiert. Anschließend wird der bogenförmige Bedruckstoff von den Greifern 14 des Greifersystems 6 an die Greifeinrichtung 8 des Zylinders 7 übergeben.
Unmittelbar nach der Übergabe des bogenförmigen Bedruckstoffs an die Greifeinrichtung 8 des Zylinders 7 werden die Greifer 14 in eine Position mittig (Mittenposition X) zum Schwinggreifersystem 9 geführt. Aus dieser Mittenposition X wird das Greifersystem 6 in eine Übernahmeposition verschoben. Diese Übernahmeposition ergibt sich dadurch, dass durch die Messeinrichtung 21 im Anlegtisch 1 und die Auswerteinheit aus der Ist-Lage und der Soll-Lage für den nachfolgenden bogenförmigen Bedruckstoff ein durch das Greifersystem 6 zu realisierender Ziehweg nach Betrag und Richtung ermittelt wird. Dabei ist es nicht erforderlich, dass der exakte Betrag des Ziehwegs bereits vorliegt. Vielmehr ist es zur Realisierung der Übernahmeposition ausreichend, wenn durch die Messeinrichtung 21/Auswerteinheit ein erster vorläufiger Messwert ermittelt wird, z.B. wenn das Bogenmaterial an den Vordermarken 2 anliegt, das Schwinggreifersystem 9 aber noch nicht geschlossen ist. In dieser Übernahmeposition wird das Bogenmaterial durch das Greifersystem 6 vom Schwinggreifersystem 9 übernommen und nachfolgend während des Transports zur Greifeinrichtung 8 das Greifersystem 6 um einen von der Messeinrichtung 21/Auswerteinheit ermittelten exakten Betrag des Ziehweges verschoben, der auf der Grundlage eines zweiten Messwertes, z.B. wenn das Schwinggreifersystem 9 das Bogenmaterial erfasst hat, generiert wird. Damit wird die Soll-Lage realisiert.
Bei einem Bogen 16 und einem Folgebogen 17, wie im Ausführungsbeispiel in Fig. 2 dargestellt, wird wie folgt verfahren. Die Bogen 16,17 werden so auf den Anlegtisch 1 gefördert, dass die Seitenkanten innerhalb des Streubereichs 22, der identisch ist mit dem maximalen Ziehweg Z, einlaufen. Die Soll-Lage ist durch die Seitenziehlinie 23 vergegenständlicht. Damit der Bogen 16 aus der Ist-Lage in die Soll-Lage gelangt, muss ein erster partieller Ziehweg e₁ realisiert werden, wobei die Ziehrichtung auf die Seitenziehlinie 23 gerichtet ist. Der Folgebogen 17 muss zur Realisierung der Soll-Lage einen zweiten partiellen Ziehweg e₂ zurücklegen, wobei die Ziehrichtung ebenfalls auf die Seitenziehlinie 23 gerichtet ist.
Zur Übernahme des Bogens 16 durch das Greifersystem 6 wird dieses in die Übernahmeposition gesteuert, die außermittig bei $\frac{e_1}{2}$

liegt. Nachfolgend wird der Bogen 16 vomIs fed to a sheet-shaped substrate, the order $\frac{Z}{}$$\frac{}{2}$

must be moved away from the side I in order to reach the desired position and thus the side-pull line 23 with respect to the side edge, the grippers 14 of the gripper system 6 by half of the pulling path to be realized $\frac{\mathrm{<figure-callout\; id="2"\; label="Z"\; filenames="imgf0001.png,imgf0002.png"\; state="\{\{state\}\}">Z</figure-callout>}}{2}$

So, um $\frac{\mathrm{<figure-callout\; id="4"\; label="Z"\; filenames="imgf0001.png,imgf0003.png"\; state="\{\{state\}\}">Z</figure-callout>}}{4}$

moved towards the side I. Thereafter, the sheet-shaped substrate is clamped by the grippers 14 of the gripper system 6 and subsequently the Gripper system 6 um $\frac{\mathrm{<figure-callout\; id="2"\; label="Z"\; filenames="imgf0001.png,imgf0002.png"\; state="\{\{state\}\}">Z</figure-callout>}}{2}$

moved away from the side I and so realized the desired position. Subsequently, the sheet-shaped printing material is transferred from the grippers 14 of the gripper system 6 to the gripping device 8 of the cylinder 7.
Immediately after the transfer of the sheet-shaped printing material to the gripping device 8 of the cylinder 7, the grippers 14 are guided in a central position (center position X) to the oscillating gripper system 9. From this center position X, the gripper system 6 is moved to a transfer position. This acceptance position results from the fact that the measuring device 21 in the feed table 1 and the evaluation unit from the actual position and the target position for the subsequent sheet-shaped printing material a determined by the gripper system 6 pulling path is determined by amount and direction. It is not necessary that the exact amount of the pulling path already exists. Rather, it is sufficient for the realization of the transfer position when a first preliminary measurement is determined by the measuring device 21 / evaluation unit, for example, when the sheet material is applied to the front mark 2, but the swing gripper system 9 is not yet closed. In this takeover position, the sheet material is taken over by the gripper system 6 from the oscillating gripper system 9 and subsequently displaced during transport to the gripping device 8, the gripper system 6 by a determined by the measuring device 21 / evaluation unit exact amount of Ziehweges on the basis of a second measured value, for example the swing gripper system 9 has detected the sheet material is generated. Thus, the target position is realized.
In a bow 16 and a subsequent arc 17, as in the embodiment in Fig. 2 is shown, proceed as follows. The sheets 16,17 are promoted to the feed table 1, that the side edges within the scattering range 22, which is identical to the maximum pull Z, shrink. The desired position is objectified by the side-line 23. In order for the sheet 16 to pass from the actual position to the desired position, a first partial drawing path e _{1 must} be realized, the drawing direction being directed to the side drawing line 23. The follower sheet 17 must cover a second partial pulling path e ₂ for realizing the desired position, wherein the pulling direction is likewise directed to the side draw line 23.
To take over the sheet 16 by the gripper system 6, this is controlled in the transfer position, the off-center at $\frac{{\mathrm{<figure-callout\; id="1"\; label="e"\; filenames="imgf0002.png"\; state="\{\{state\}\}">e</figure-callout>}}_1}{2}$

lies. Subsequently, the sheet 16 of

Gripper system 6 taken over and this in the axial direction and in the direction of the side line 23 and the side I shifted by the first partial pulling path e ₁ , so that the sheet 16 is brought into the desired position. Subsequently, the sheet 16 is transferred to the gripping device 8. Thereafter, the gripper system 6 and thus the gripper 14 in its center position X, ie moved centrally with respect to the gripper fingers 10 of the swing gripper system 9.

In parallel, the actual position of the follower sheet 17 is detected by the measuring device 21 and a second partial pulling path e ₂ and the drawing direction, which is directed away from the side I and directed to the side line 23, detected. Starting from this second partial pulling path e ₂ and the determined pulling direction, the gripper system 6, initiated by the evaluation unit downstream evaluation unit, controlled from the center position X in the takeover position for the subsequent sheet 17.

von der Seitenziehlinie 23 beabstandet. In dieser Übernahmeposition wird der Folgebogen 17 von dem Greifersystem 6 erfasst und das Greifersystem 6 um den zweiten partiellen Ziehweg e₂, initiiert durch die Messeinrichtung 21, in Richtung der Seitenziehlinie 23 verschoben und so die Soll-Lage des Folgebogens 17 realisiert. Nach der Übergabe des Folgebogens 17 an die Greifeinrichtung 8 des Zylinders 7 werden die Greifer 14 des Greifersystem 6 in ihre Mittenposition X geführt.The takeover position is again off-center, around half of the second partial drawing path $\frac{e_{}}{}$$\frac{{}_2}{2}$

spaced from the side-pull line 23. In this takeover position of the follower sheet 17 is detected by the gripper system 6 and the gripper system 6 to the second partial pulling path e ₂ , initiated by the measuring device 21, moved in the direction of the side draw line 23 and so realized the desired position of the follower sheet 17. After the transfer of the follower sheet 17 to the gripping device 8 of the cylinder 7, the grippers 14 of the gripper system 6 are guided into their middle position X.

List of used reference numbers

1

feed table

2

front lay

3

Sheet acceleration device

4

swing feeder

5

drum

6

gripper system

7

cylinder

8th

gripper

9

Schwinger gripper system

10

gripper fingers

11

Gripper bar

12

sheet grippers

13

Gripper pad

14

grab

15

gripper

16

foremost bow

17

episode arc

18

Sheet conveying direction

19

recess

20

Format Range

21

measuring device

22

stray field

23

Side pull line

a

width

b

distance

c

system distance

Z

maximum pulling distance

e ₁

first partial pulling way

e ₂

second partial drawing way

X

center position

Claims (2)

1. Method of aligning sheets with respect to the side edge, in which the sheets to be aligned are conveyed within a tolerance range (22) on a feed table (1)

   - and the actual position of the side edge is established by means of a measuring device (21) as well as picked up by a sheet accelerating device (3) and led to a gripper system (6) of a drum (5),

   - the gripper system (6) is for realisation of a target position, which is concretised by a side draw line (23) provided approximately centrally in the tolerance range (22), constructed to be displaceable in axial direction from its central position (X) to a first side or to a second side,

   - a first partial draw path (e₁) over which the foremost sheet (16) has to be displaced in the direction of side draw line (23) for realisation of the target position is detected by the measuring device (21) and an evaluating unit connected therewith,

   - half of the first partial draw path (e₁/2) is formed in the measuring device (21) and an evaluating unit connected therewith,

   - the gripper system (6) of the drum (5) is controlled by the measuring device (21) from a central position (X) in which the gripper system (6) is disposed centrally with respect to an oscillatory gripper system (9) of the sheet accelerating device (3) into a transfer position which extends offset by half the first partial draw path (e₁/2) relative to the central position (X) of the gripper system (6) in the direction of the side of the sheet (16),

   - the foremost sheet (16) is taken over by the gripper system (6) from the sheet accelerating device (3) and transported to a gripper device (8) of a cylinder (7),

   - in that case the gripper system (6), initiated by the measuring device (21) and an evaluating unit connected therewith, is displaced over the first partial draw path (e₁) in the direction of the side draw line (23) and subsequently the foremost sheet (16) is transferred to the gripper device (8),

   - the gripper system (6) is thereafter led back to the central position (X), and

   - at the same time a second partial draw path (e₂) of a succeeding sheet (17) is determined by the measuring device (21) and an evaluating unit connected therewith and half the second partial path (e₂/2) formed for bringing the gripper system (6) into the takeover position for the succeeding sheet (17).
2. Method according to claim 1, characterised in that the measuring device (21) can be displaced transversely to a sheet conveying direction (18) in the feed table (1) for format adaptation.

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