EP2407402B1 - Method and device for positioning sheets - Google Patents

Description

The invention relates to a method for positioning sheets with the features of claim 1 as well as an apparatus for positioning sheets according to the preamble of claim 7.

State of the art

As punching the cutting is referred to with closed geometric blank forms that can be circular, oval or polygonal and imaginary shapes of all kinds. Also the practices practiced in print finishing, such as punching with punch, corner punching and register punching are counted to this area. The punching takes place against a punching pad or against stamp, in some cases it is also shearing operations. Packaging materials made of paper, cardboard, cardboard or corrugated board are mainly punched in sheet format. When punching but also creasing lines or blind embossing can be introduced into the benefit. This complex process makes it indispensable to punch the sheets individually. Since the end products are sophisticated packaging in terms of technical and graphic design (such as packaging for cosmetics, cigarettes, pharmacy, food, etc.), special requirements are not only placed on the packaging materials themselves, but are also punching tools for optimum results required with the smallest tolerances and extremely precise and reliable punching machines. Flatbed punching best meets these demands. The printed sheets stacked on a pallet are fed to the punching machine. In the machine, the sheets to be punched are precisely aligned in an alignment device, taken over by a gripper carriage and positioned exactly in the punching device between a fixed undercounter and a vertical over a knee lever or eccentric upper table.

In known sheet punching and embossing machines, which are used for punching, breaking, stamping and depositing sheets of paper, cardboard and the like, it is known to move the sheets by means of gripper carriage through the individual stations of the machine. Grippers are attached to the gripper carriage, gripping the arches at a front end, the gripper carriages themselves being moved through the machine on endless chains. This type of movement of the sheets through the machine enables continuous operation in the individual successively arranged stations of the machine.

Such a flat bed punch is for example from the DE 30 44 083 A1 known. The two tables are equipped with cutting and scoring tools or corresponding counter tools with which punched out of the cyclically guided between the table surface sheets the benefits and at the same time pressed the necessary for clean folding grooves. In the subsequent breakout the waste is removed by machine tools. Depending on the equipment of the machine finally the punched benefits can be separated in a designated Nutzentrenneinrichtung.

In order to achieve a high product quality of the punched sheets, it is necessary that the sheets and tools are precisely aligned with each other. In the punching station of a sheet punching and embossing machine, the punching tool and punched riddle plate must be brought to an exact position in the circumferential direction. It must also be ensured that both tools are directly perpendicular to the sheet transport direction without skewing. This reference position is called "first knife". In the subsequent processing stations, the tools must be adjusted relative to the position of the first knife, such. B. the stripping board in the breaker and the Nutzentrenngitter in the Nutzentrennstation. The tools must be set in their three degrees of freedom. During operation of the sheet punching and embossing machine, it may be necessary to readjust the position of the tools in the punching station. The tools in the subsequent processing stations must also be readjusted to bring them back into the correct position relative to the "first knife". The terminology "Aligning", "Positioning" and "Correcting the Position" of an arc are used synonymously below.

This elaborate adjustment work of the tools ensures that the sheets are processed accurately. The register describes the positional accuracy of the printed image at the cutting, creasing and breaking edges of the sheet. A distinction is made between circumferential flow, i. the registration in the machine direction and side registration, i. the positional accuracy transverse to the machine direction.

A disadvantage of the register-accurate alignment of the prior art is that due to the high set-up times, i. due to the high time required for the adjustment of the tools, the machine productivity is impaired.

• Die DE OS 25 20 232 beschreibt eine Vorrichtung zur Übergabe von Bogen an eine Bogenverarbeitende Maschine. Dabei werden im Bereich eines Zuführtischs eine auf den Bogen aufgedruckte Marke, eine sogenannte Druckmarke, oder eine Seitenkante des Bogens durch Sensoren erfasst und der Zuführtisch wird quer zur Bogentransportrichtung so verschoben, dass der Bogen in seiner richtigen, seitenausgerichteten Lage an das Bogentransportsystem der Bogenverarbeitenden Maschine übergeben werden kann.

From the prior art various measuring devices are known, which are preceded by the accurate register alignment of a sheet:

• The DE OS 25 20 232 describes a device for transferring sheets to a sheet processing machine. In this case, in the area of a feed table, a mark printed on the sheet, a so-called print mark, or a side edge of the sheet is detected by sensors and the feed table is moved transversely to the sheet transport direction so that the sheet in its correct, side-facing position to the sheet transport system of the sheet processing machine can be handed over.

The DE 693 14 155 T2 describes a method for monitoring moving web material, wherein the edges of the web are detected by sensors.

The DE 202 16 042 U1 shows a device for detecting the edges of sheets in sheet-processing machines. The device comprises a line sensor, which is connected to an evaluation unit, and in which the sheet position is calculated from the signal of the sensor.

Also from the DE 101 36 870 A1 A device for detecting the position of an edge of a sheet in a printing machine emerges. In the feed table of the printing press is a

Scanner line, this scanner line is assigned to a reflector located above the feeder table. Similar facilities also go out of the DE 101 36 871 A1 , of the DE 101 36 872 A1 , of the DE 101 36 873 A1 , of the DE 101 36 874 A1 , of the EP 1 300 353 A2 and the EP 1 300 354 A2 out.

The DE 10 2008 012 775 A1 relates to a method for measuring the position of a sheet in the feeder of a printing or post-processing machine, wherein the measurement of the position of the sheet on the measurement of the position of the sheet leading edge or the location of printed on the sheet marks by means of a sensor. Furthermore, the invention relates to a method for aligning the sheet based on the measurement results.

The EP 1 518 803 B1 describes a positioning device for sheets in the feeder of a sheet-processing machine. The alignment in the circumferential direction via front stops and in side orientation by a controlled puller rail based on the measurement results of a target-actual position comparison by means of sensors.

task

The object of the present invention is to develop the state of the art and to describe a method for positioning sheets as well as a device for carrying out the method, wherein an exact positioning with high reliability is ensured and the device has a robust construction.

• Die Positionierung erfolgt dabei ohne die Verwendung von Front- oder Seitenanschlägen. Eine Grobpositionierung des Bogens (6) in Umfangs- und Schrägrichtung erfolgt durch ein gesteuertes Anhalten des Bogens (6), eine Seitenausrichtung erfolgt im Bereich eines Zuführtisches (16), eine Feinpositionierung in Umfangs- und Schrägrichtung erfolgt durch eine Positionierung von Passeranschlägen (713, 714) eines Bogentransportsystems (7).

This object is achieved by a method having the features of claim 1 and by a device having the characterizing features of claim 7:

• The positioning takes place without the use of front or side stops. A coarse positioning of the sheet (6) in the circumferential and oblique directions is effected by a controlled stopping of the sheet (6), a page orientation takes place in the region of a feed table (16), a fine positioning in the circumferential and oblique directions is carried out by a positioning of Passeranschläge (713, 714) of a sheet transport system (7).

The inventive method for positioning sheets for subsequent processing in a sheet-processing machine has the following steps: In a first step, sheets of paper, cardboard, plastic and the like, for example, fed from a sheet feeder via a feed table. By acting on a respective sheet transport and pressing the sheet is transported in the next step. This is followed by a measurement of the position of the sheet leading edge of the sheet in motion. The measurement can either be done before the sheet is transported by the transport and pressing device or after the sheet is transported by the transport and pressing device. Based on the measured sheet position in the next step, the required correction movement is determined both in the circumferential direction and in oblique direction to the sheet transport direction of the sheet, for which the deviation of the arc in the circumferential and oblique directions is determined by the target position. Next, the alignment of the sheet in the circumferential and oblique direction to the sheet transport direction by a corresponding control of the transport and pressing device takes place. After completion of this alignment movement of the sheet is stopped by the transport and pressing device, that is braked to zero speed. After the sheet is at rest and clamped by means of a clamping device, in the next step, a measurement of the position of the sheet in the transverse direction to the sheet transport direction. In addition, there is still a measurement of the position of the sheet in the circumferential direction and oblique direction to the sheet transport direction. Based on the measurement results, on the one hand, the required correction movement in the transverse direction and, on the other hand, the required correction movement in the circumferential and oblique directions are determined. This is done by determining the deviation between the measured actual position and the intended target position. The sheet is then oriented transversely and undergoes the required correction movement in the transverse direction to the sheet transport direction by movement of the clamping device. In a next step, which can alternatively take place at the same time for aligning the sheet in the transverse direction, a gripper device is positioned at least in the circumferential and oblique directions to realize the required correction movement in the circumferential and oblique directions to the sheet transport direction. While the orientation of the sheet in the circumferential and oblique directions by the transport and pressing device as In the final step, the sheet is transferred from the clamping device to the positioned gripper device while the gripper device is in a sheet transfer position. The precisely positioned in this way sheet can then be transported by the gripper device for processing the sheet by a sheet-processing machine, such as a sheet-fed press or a sheet punching machine.

In an advantageous development of the positioning method according to the invention, the measurement of the position of the sheet in the transverse direction is carried out simultaneously for measuring the position of the sheet in the circumferential direction and oblique direction. Also or alternatively, the alignment of the sheet in the transverse direction by the movement of the clamping device and the positioning of the gripper device also takes place simultaneously. Thereby, the positioning of a respective sheet can be advantageously accelerated and the aligned sheets can be fed at high clock frequency of a subsequent sheet-processing machine, which can be operated with high productivity.

Another advantageous development of the method for positioning relates to the measurement of the sheet positions: Thus, in the above-mentioned method steps in which a measurement of the sheet position takes place, either a measurement of sheet edges or of a printed image applied to the sheet or of the sheet applied print marks done. In addition to this alternative measurement, it is also possible to carry out a combined measurement in any desired combination, that is to say for example a measurement of the sheet edge and printed image or a measurement of the sheet edge and printed marks. It is also possible to provide a different type of measurement for a particular surveying operation. For example, the first measurement, which serves for coarse positioning in the circumferential and / or oblique directions, can be made by measuring the position of the sheet leading edge, while the subsequent measurements, while the sheet is at rest, are made by measuring the printed image.

In an alternative and simplified embodiment of the method according to the invention for positioning sheets, fine positioning in the circumferential direction and oblique direction is dispensed with. This is particularly useful when the product to be produced is not subject to high accuracy requirements, for example in the processing of corrugated board.

The invention also relates to a device for positioning sheets of paper, cardboard, plastic and the like for subsequent processing in a sheet-processing machine, such as a sheet-fed press or a sheet punching machine, by means of which the above-described method for positioning sheets is feasible. According to the invention, the device has no leading edge stop. It has at least two parallel to each other in the region of a feed plane arranged pressing elements, which constitute a transport and pressing device for the first alignment of the sheet in the circumferential and oblique directions. The gripper device is designed as a gripper carriage with grippers attached to a gripper bar. In a first embodiment, a respective pressing element is designed as a pair of rollers with at least one driven roller. In a second alternative embodiment, a respective pressing element is designed as a driven roller, which is employed against a, located in the sheet transport plane support surface.

In an advantageous embodiment of the device according to the invention, the clamping device, which serves to align the sheet in the transverse direction, designed as a transversely displaceable to the sheet transport direction drawing rail executed against it employed at least two rollers. In an alternative embodiment, the clamping device may be formed by at least two pairs of rollers, wherein at least one roller of a respective pair of rollers is driven. In a further embodiment, the clamping device is designed as a transversely displaceable squeegee.

In an advantageous development of the device according to the invention has these Passeranschläge, which are associated with a respective end of the gripper bar, for Aligning accurate alignment of a gripper carriage in the sheet transfer position. A respective Passeranschlag is connected to a controllable drive, for adjusting the Passeranschlags. Such Passeranschläge are in the EP 1 371 588 B1 to which reference is hereby made in full and which is made the subject of this description.

The described invention and the described advantageous developments of the invention are also in any combination with each other advantageous developments of the invention.

With regard to further advantageous embodiments of the invention, reference is made to the dependent claims and the description of embodiments with reference to the accompanying drawings.

embodiment

Fig. 1

eine Flachbett-Bogenstanz- und/oder -prägemaschine

Fig. 2

a-d den Ablauf der Bogenausrichtung in einer Draufsicht

Fig. 3

a-d den Ablauf der Bogenausrichtung in einer Ansicht

Fig. 4

a-b alternative Ausführungsformen der Transport- und Presseinrichtung

Fig. 5

a-c alternative Ausführungsformen der Klemmeinrichtung

Fig. 6

alternative Messarten zur Bestimmung der Lage eines Bogens

The invention will be explained in more detail with reference to exemplary embodiments. It show in a schematic representation

Fig. 1

a flatbed sheet punching and / or embossing machine

Fig. 2

ad the course of the sheet orientation in a plan view

Fig. 3

ad the process of sheet orientation in a view

Fig. 4

from alternative embodiments of the transport and pressing device

Fig. 5

ac alternative embodiments of the clamping device

Fig. 6

alternative measuring methods for determining the position of an arc

In FIG. 1 the basic structure of a sheet punching and embossing machine 1000 for punching, breaking, depaneling and depositing sheets of paper, cardboard and the like is shown. The punching and embossing machine 1000 has a feeder 1, a punching station 2, a breaking station 3 and a boom 4, which are supported and enclosed by a common machine housing 5. From one side, the so-called operator side, the processing stations 2, 3, 4 are accessible; on the opposite side, the so-called drive side, there is the drive train of the sheet punching and embossing machine 1000.

The sheets 6 are separated by a feeder 1 from a stack, aligned (see Fig. 2-5 ), fed to the sheet transport system 7 and gripped by gripper bridges of a gripper carriage 8 grippers at its front edge and intermittently pulled in the sheet transport direction B through the various stations 2, 3 and 4 of the punching and embossing machine 1000.

The sheet transport system 7 has a plurality of gripper carriages 8, so that a plurality of sheets 6 can be processed simultaneously in the various stations 2, 3 and 4. The gripper carriage 8 can be driven by a chain drive or in an alternative embodiment by an electromagnetic linear drive with traveling wave motors. Such a drive system is the expert from the DE 20 2007 012 349 U1 known.

Also, the sheet punching and embossing machine may have separate drives of the sheet transport system and the individual processing stations.

The punching station 2 consists of a lower crucible, a so-called. Under table 9, and an upper crucible, a so-called. Obertisch 10. The upper table 10 is vertically reciprocally mounted and provided with an upper tool with punching and Rillmessern. The lower table 9 is fixedly mounted in the machine frame and provided with a counter plate to the punching and Rillmessern. Alternatively, the upper table 10 fixed and the lower table 9 may be moved. In embossing, embossing tools, in particular in the form of so-called embossing dies, are used instead of the punching and scoring tools.

The gripper carriage 8 transports the sheet 6 from the punching and embossing station 2 in the subsequent breaking station 3, which is equipped with breakout tools. In the break-out station 3, the unwanted pieces of waste are pushed out of the sheet 6 downwards by means of the break-off tools, whereby the waste pieces 11 fall into a carriage-like container 12 inserted below the station.

From the breaking station 3, the sheet 6 enters the boom 4, where the sheet 6 is either simply stored, or at the same time there is a separation of the individual benefits of each sheet 6. The boom 4 may also include a pallet 13, on which the individual sheets 6 are stacked in the form of a stack 14, so that after reaching a certain stack height, the pallet 13 can be moved away with the sheet stack 14 from the field of punching and embossing machine 1000 ,

In the FIGS. 2a to 2b the sequence of aligning or positioning a sheet 6 by means of an aligning device 100 over time is shown. An arc 6 is coming from a feeder 1 on a feed table 16 aligned before it is subsequently processed, for example in a punching station 2. A sheet 6 is transported as far as the feed table 16 until independently driven transport and pressing elements 103, 104 the bow 6 capture and effect the further transport of the sheet 6. In the vicinity of the driven transport and pressing elements 103, 104 sensors 101, 102 for circumferential measurement and angular position measurement of the sheet 6 are attached. The sensors 101, 102 are in Fig. 2a represented as a filled circle, since they are at the time of Fig. 2a shown snapshot are active and determine the position of the sheet leading edge of the sheet 6, ie it is the position of the sheet 6 in the circumferential direction - ie in the sheet transport direction B - and the position of the sheet 6 measured obliquely to this direction. Thus, it is found that the sheet 6 has an output skew of α1, as well as a slight deviation in the circumferential direction. From one to the Figures 2 not shown machine control 15, the correction requirement is determined to spend the sheet 6 from its actual position in terms of circumference and skew in its desired position. This correction is implemented by an alignment movement e of the independently driven transport and pressing elements 103, 104, as shown in FIG Fig. 2b is indicated. The sheet 6 is of the transport and pressing elements 103, 104, as in Fig. 2c shown, brought into its transfer position, during the transport of the sheet 6 in its transfer position by the individual control of the transport and pressing elements 103, 104, the circumferential orientation and the inclination of the sheet 6 is corrected. How out Fig. 2c As can be seen, the initial initial bank angle α1 has been substantially reduced so that the arc 6 is now in a corrected bank angle α2. From the transport and pressing elements 103, 104 of the sheet 6 is braked to zero speed, ie stopped and then clamped. The clamping is realized in that the clamping or pressing elements 107, 108 are brought into their operative position and press the sheet 6 against a pulling rail 109. The stopped sheet 6 is measured in its rest position by sensors 110, 111 in the circumferential direction, inclined position and lateral direction. Thus, to measure the lateral position of the sheet 6, the distance of the respective side edges of the sheet from its respective desired position is determined. In the example of Fig. 2c the arch 6 is too far left. The active state of the sensors 110, 111 is indicated by a running circle. In one in the Figures 2 not shown machine control 15, the correction requirement of the sheet 6 is determined both in the circumferential and oblique directions and in the lateral direction. The drawing rail 109 is moved by a drive, not shown, transversely to the sheet transport direction B and thereby performs, as in Fig. 2d shown, an alignment movement 1 as a correction movement in the lateral direction by: The sheet 6 is further moved to the right until it assumes its lateral desired position. Based on the measurement results of the sensors 110, 111 for sheet position in the circumferential direction and inclined position determined in the Figures 2 not shown machine control 15 a further correction need to spend the sheet 6 with respect to its oblique orientation and its circumferential orientation in its desired position. This fine correction is implemented by positioning the transport grabber bridge 8.1. In the in Fig. 2d illustrated transfer position of the sheet 6, the transport gripper bridge 8.1 of independently adjustable Passeranschlägen 713, 714 stopped and aligned. A respective Passeranschlag 713, 714 is an independent, controllable by the machine control 15 servomotor 715, 716 assigned. Corresponding to the correction requirement in the circumferential direction and oblique direction determined by the machine control 15, the servomotors 715, 716 are actuated and execute a positioning action of the register stops 713, 714. Once the lateral alignment of the sheet 6 by the clamping or pressing elements 107, 108 are carried out together with the drawing rail 109 and the positioning of the transport gripper bridge 8.1, the holding force of the clamping or pressing elements 107, 108 can be repealed and the sheet. 6 are taken by the grippers of the gripper bridge 8.1 not shown in detail. The thus positioned in its three degrees of freedom arc 6 can then from Sheet transport system 7 are transported by subsequent processing stations 2, 3, 4, where a register-accurate processing of the sheet 6 can take place.

To clarify the alignment of an arc 6 of the process in the FIGS. 3a to 3d shown in a side view. These figures show that the independently driven transport and pressing elements 103, 104 only act on the sheet 6 until it is in its transfer position. As in Fig. 3d illustrated, then the pressing action of the transport and pressing elements 103, 104 is repealed, for example by the upper transport rollers are raised. In return, the clamping or pressing elements 107, 108 are in the FIGS. 3a to 3c in a raised position and are only lowered when the sheet 6 is in its sheet transfer position, as in Fig. 3d shown.

• Gemäß der Darstellung von Fig. 4a sind die unabhängig angetriebenen Transport- und Presselemente als absenkbare Rollen 103, 104 ausgeführt, welche einen Bogen 6 gegen eine sich in dem Zuführtisch 16 befindliche Auflagefläche 112 pressen. Die Detektoren 101, 102 zur Umfangs- und Schrägvermessung sind - in Bogentransportrichtung betrachtet - stromabwärtig der Transport- und Presselemente 103, 104 angeordnet und beispielhaft als Kamerasystem ausgeführt. In einer alternativen, in Fig. 4b dargestellten Ausführungsvariante sind die Detektoren zur Umfangs- und Schrägvermessung 101, 102 beispielhaft als optische Sensoren ausgeführt, welche - in Bogentransportrichtung B betrachtet - stromaufwärtig der Transport- und Presselemente 103, 104 angeordnet sind. Die Transport- und Presselemente 103, 104 sind jeweils als Rollenpaar ausgebildet, wobei zumindest eine Rolle eines jeweiligen Rollenpaars gegen die andere Rolle zustellbar ist und wobei zumindest eine der beiden Rollen angetrieben ist.

By means of the others FIGS. 4, 5 and 6 further embodiments are described and illustrated:

• As shown by Fig. 4a the independently driven transport and pressing elements are designed as lowerable rollers 103, 104, which press a sheet 6 against a located in the feed table 16 support surface 112. The detectors 101, 102 for circumferential and oblique measurement are - viewed in the sheet transport direction - arranged downstream of the transport and pressing elements 103, 104 and exemplified as a camera system. In an alternative, in Fig. 4b illustrated embodiment, the detectors for circumferential and oblique measurement 101, 102 are exemplified as optical sensors, which - viewed in the sheet transport direction B - upstream of the transport and pressing elements 103, 104 are arranged. The transport and pressing elements 103, 104 are each formed as a pair of rollers, wherein at least one roller of a respective pair of rollers against the other role is deliverable and wherein at least one of the two rollers is driven.

Fig. 5a engages the embodiment of the clamping or pressing elements 107, 108 in combination with a pulling rail 109, as they are already in the Figures 2 and 3 A respective clamping or pressing element 107, 108 is shown as freely rotatable Roller performed, this role against a located in the plane of the feed table 16 drawbar 109 deliverable, ie lowered, and thus causes a sheet 6 can be pressed against the pulling rail 109. The lying in the sheet transport plane E sheet 6 (not shown) can then be subjected by the drawing rail 109 of an alignment movement in the transverse direction 1. In the alternative embodiment according to Fig. 5b the pulling rail 109 was replaced by driven rollers 107, 108. The rotational movement of the rollers 107, 108 causes an alignment movement in the transverse direction 1 of a sheet 6 (not shown). In another, in Fig. 5c illustrated embodiment, the alignment movement in the transverse direction 1 of a sheet 6 (not shown) is achieved by the transverse displacement of a suction bar 113 equipped with suction nozzles. During the alignment process, a respective sheet 6 is sucked by the suction pad 113, so that the transverse movement of the suction pad 113 is transferred to the sheet 6. The design of the squeegee 113 as a clamping element is not described in detail below, since such squeegees are well known to those skilled in the art and whose design is thus at the discretion of the skilled person.

As in Fig. 6 shown, a respective sheet 6 may be provided with print marks 6.2 and 6.1 a print image. In the determination of the actual position of a respective sheet 6 by the sensors 101, 102 and 110, 111, the position of the print marks 6.2 and / or the print image 6.1 can then be measured. In the machine control 115, not shown, a comparison of the actual position of the print marks 6.2 and 6.1 of the print image can then be drawn with the desired position. From this, as described above, a corresponding correction requirement can be calculated.

LIST OF REFERENCE NUMBERS

1

investor

2

punching station

3

stripping

4

boom

5

machine housing

6

Sheet 6.1 Print image 6.2 Print mark

7

Sheet transport system

8th

gripper carriages

8.1

Transport gripper

9

under table

10

overtable

11

trimmings

12

container

13

palette

14

delivery pile

15

Control with interface and input devices

16

feed

20

lower tool

30

upper tool

100

straightener

101, 102

Sensors for circumferential and oblique measurements

103, 104

independently driven transport u. pressing elements

107, 108

Clamping or pressing elements

109

formed template

110

111 sensors for circumferential, oblique and. page survey

112

bearing surface

113

transversely movable squeegee with suction nozzles

713, 714

independently adjustable register stops

715, 716

independent servomotors

1000

Sheet punching and embossing machine

e

Alignment movement (oblique and circumference)

1

Alignment movement (cross)

m

Alignment movement (oblique and circumference)

B

Sheet transport direction

e

Sheet transport plane

α 1

Output skew

α 2

corrected skew

Claims (10)

1. Method for positioning sheets (6) of paper, cardboard, plastic and the like for a subsequent processing step in a sheet-processing machine (1000), in particular a sheet-fed printing press or diecutting machine, comprising the steps of

   a) feeding a sheet (6)

   b) transporting the sheet (6) by a transporting and pressing device (103, 104) that acts on the sheet,

   c) measuring the position of the sheet (6) in the circumferential and oblique directions relative to the sheet transport direction (B) during movement

   d) determining a required corrective movement in the circumferential and oblique directions relative to the sheet transport direction (B)

   e) aligning (e) the sheet (6) in the circumferential and oblique directions relative to the sheet transport direction (B) by correspondingly actuating the transport and pressing device (103, 104)

   f) stopping the sheet (6) by the transport and pressing device (103, 104)

   g) clamping the sheet (6) by a clamping device (107, 108, 109)

   h) measuring the position of the sheet (6) in the transverse direction

   i) measuring the position of the sheet (6) in the circumferential and oblique directions

   j) determining the required corrective movement in the transverse direction

   k) determining the required corrective movement in the circumferential an oblique directions

   l) aligning (1) the sheet (6) in the transverse direction by a movement of the clamping device (107, 108, 109)

   m) positioning (m) a gripper device (8, 8.1) at least in the circumferential and oblique directions

   n) transferring the sheet (6) from the clamping device (107, 108, 109) to a gripper device (8, 8.1) while the gripper device (8, 8.1) is in a sheet transfer position.
2. Method for positioning sheets (6) according to any one of the preceding claims, wherein the sheet (6) is stationary during steps h) and i).
3. Method for positioning sheets (6) according to any one of the preceding claims, wherein the steps h) and) are carried out simultaneously and/or wherein the steps 1) and m) are carried out simultaneously.
4. Method for positioning sheets (6) according to any one of the preceding claims, wherein the measurement according to step c) is taken before or after the sheet (6) has been transported by the transporting and pressing device (103, 104) in accordance with step b).
5. Method for positioning sheets (6) according to any one of the preceding claims, wherein during steps c) and/or h) and i) a measurement is taken of the edge of the sheet and/or of the printed image (6.1) on the sheet and/or of print marks (6.2) on the sheet.
6. Method for positioning sheets (6) according to any one of the preceding claims, wherein in a simpler embodiment, steps i), k) and m) are dispensed with.
7. Device (100) for positioning sheets (6) of paper, board, plastic and the like for a subsequent processing step in a sheet-processing machine (1000), in particular a sheet-fed printing press or a sheet-fed diecutting machine for carrying out the method according to Claim 1,
   characterized in
   that the transporting and pressing device (103, 104) is embodied as at least two pressing elements arranged to be parallel to each other and that the gripper device is a gripper carriage (8) with grippers fixed to a gripper bar (8.1).
8. Device for positioning sheets according to Claim 7,
   characterized in
   that a respective pressing element (103, 104) is embodied as a roller pair with rollers that are driven in opposite directions or as a driven roller engaged with a support surface located in the plane of sheet transport.
9. Device for positioning sheets according to Claim 7 or 8,
   characterized in
   that the clamping device is embodied as a pulling bar (109) with at least two rollers (107, 108) engaged therewith or as two pairs of rollers (107, 108) or as a suction bar (113) movable in a transverse direction.
10. Device for positioning sheets according to Claim 7, 8 or 9,
    characterized in
    that it includes register stops (713, 714) associated with a respective gripper bar end for an in-register alignment of a gripper carriage (8) in the position of sheet transfer, a respective register stop (713, 714) connected to a controllable drive (715, 716) for adjusting the register stop (713, 714).

Images