EP1924435B1 - Printing press and method for register adjustment - Google Patents

Description

The invention relates to a drive system for a printing press according to the preamble of patent claim 1 and to a method for register correction or correction of a faulty arrangement according to the preamble of patent claim 6.

State of the art

In the following, reference will be made essentially to rotogravure printing presses without the invention being restricted to this application.

Multi-color presses have a separate print engine available for each color. The material to be printed (paper, cardboard, fabric, etc.) passes through the respective printing units one after the other, which is why the individual color prints must be applied exactly congruent.

In a gravure printing machine, a printing unit consists inter alia of a printing cylinder, on which the printed image is applied, and a counter-pressure cylinder (impression roller), which presses the paper onto the printing cylinder. In contrast to flexo or off-set printing presses, the impression cylinder is not driven.

The impression roller is made with high pressure against the printing material and the printing cylinder, so that a frictionally connected unit is formed, which can only be moved together or positioned. There is no relative movement between printing material and impression cylinder possible.

Longitudinal register deviations are corrected by cylinder correction. The task of the correction or register control is to compensate for misalignments and to ensure the register accuracy of the printed image. For this purpose, a printing cylinder is corrected by a suitable angular position. Due to the uniform connection between the printing unit and the printing material, the printing material is also moved along. Thus, it does not initially change the impression on the printing material, but to an additional stretching or compression of the material by changing the web tension.

If, for example, a printing unit is corrected such that the web is lengthened in front of the printing unit and the web is shortened after the printing unit, the material is stretched in front of the printing unit and released after the printing unit. It creates a strain difference. Only by the continuous transport of the material, this strain and web tension difference is reduced again and the adjustment of the register according to the corrected angular position is effective.

In addition, the change in the web elongation in the area after the corrected printing unit affects the subsequent printing units. It comes to register deviations in the subsequent printing units, which only slowly, but independently and unregulated, reduce again. The time required for this is a multiple of the quotient of web length and web speed. Material completed during this correction time is faulty and can not be used (waste).

This effect of a correction on subsequent printing units also prevents the subsequent printing units could be corrected separately during this time. A dynamic optimization of register control is not possible.

The EP 0 422 412 A1 shows a sheet-fed press with a non-adjustable printing unit. In order to correct a register deviation at this printing unit, all previous printing units are adjusted. The conditions in a sheet-fed press, however, are not transferable to a web press, in particular, no effects on a web tension can occur.

It is therefore the task to accelerate the register correction and to reduce the coupling between the individual printing units.

This object is achieved by a drive system of a printing press having the features of patent claims 1 and 2 and a method having the features of patent claim 6.

Advantageous embodiments emerge from the respective subclaims and the following description.

Advantages of the invention

In a drive system according to the invention for a printing press, in particular a shaftless gravure printing machine, with a plurality of individually driven printing units, which are provided with Längsregisterverstellvorrichtungen, are means for common adjustment of Längsregisterverstellvorrichtungen all preceding a first printing unit printing units or means for common adjustment of Längsregisterverstellvorrichtungen the first printing unit and all arranged after the first printing unit printing units for correcting a register deviation provided on the first printing unit. Due to the common setting or operation, the printing units are similarly adjusted, i. it is carried out in all a same correction of the angular position of the printing cylinder. It is understood that the invention also includes the case that only one printing unit is present before or after the relevant first printing unit. As a suitable means for the realization of electric drives are essentially suitable, which drive the components of the printing press by means of a virtual master axis individually and synchronously.

By the measures according to the invention the targeted influencing of the web elongation by the correction of the angular position only in the area before a first printing unit, in which there is a register deviation, until the next clamping effective. This clamping is typically represented by another printing unit. The change in elongation can be achieved by repositioning all printing units be accomplished before the relevant printing unit. It is also possible to change the elongation in front of the relevant printing unit by correcting the relevant printing unit itself and all subsequent printing units. Overall, the material strain is changed only in front of the relevant first printing unit, without affecting the register and the material expansion in other sections. Due to the subsequent reduction of the material strain change, the register deviation is corrected.

According to the invention, means for adjusting an intake unit and / or a pull-out unit are also provided in the drive system according to the invention. The register correction can therefore be realized both in the direction of the extension unit and in the direction of the intake unit or in both directions. An adjustment of the intake unit and / or the extension unit is advantageous for the decoupling, the control and maintenance of the web tension. Thus, printing material damage, such as Cracks, folds, folds or kinks etc. are reduced.

Advantageously, in a device according to the invention at least one Längsregisterverstellvorrichtung is provided for performing a cylinder correction. Cylinder correction provides a simple and reliable way to perform register correction without the need for additional mechanical or electrical devices, such as compensators conventionally used in the art Track area between two printing units are to be arranged to change the web length in this area.

Expediently, a device according to the invention has detection devices for detecting the register deviation, wherein each detection device is associated with a printing unit. Depending on the selected approach (train / train or train / cylinder method), a detection device is located within the web section immediately before the associated printing unit or behind the printing unit. If a detection device detects a register deviation, the associated printing unit is corrected in the manner described.

There are two possible methods for register deviation detection, the web / web process or the web / cylinder process. It is expedient that a device according to the invention is equipped with means for carrying out either the web / cylinder process or the web / web process. In the web / cylinder process, the position of a mark printed in the first printing unit is tracked. The pressure mark detection devices or brand readers usually sit in front of the associated printing units. The position of the impression cylinder is detected at the time the mark passes the mark reader. The cylinder position is compared with a preset setpoint. A detected difference corresponds to the register deviation. Advantageously, in the web / cylinder process, cheaper label readers can be used which need not be designed color-sensitive. In the web / web process, each brand's own brands are applied to the print material in the respective printing unit color. The sensor or brand reader associated with a printing unit is therefore color-sensitive and is arranged on the web after the associated printing unit. The distance between the individual print marks to each other is detected and compared with a distance setpoint. A detected difference corresponds in turn to the register deviation.

In a method according to the invention for register correction in which a material is processed in successive processing steps, wherein the register deviation of the material is corrected with respect to a first processing step, the mislocation is changed by a change in position within all processing steps before the first processing step or by a position change during the processing corrected first processing step and all lying in the machining process after the first processing step processing steps. Thus, an influence of the correction can be favorably limited to the section under consideration. An effect of the correction on other processing devices is reduced. It should be noted that the phrase "all processing steps" also includes only one existing processing step.

It is advantageous if the method is used in conjunction with a printing or paper processing machine, in particular a shaftless gravure printing machine. Here all occur with regard to the printing press according to the invention advantages as well. In addition to being used for printing or paper processing methods, use is equally advantageous for any method in which a processing material is accurately and sequentially processed in individual processing devices, such as e.g. Printing machines for packaging or commercial use, narrow web machines for labels and forms.

Usually, the processing steps are carried out by means of printing units, feed units and pull-out units. In this embodiment, in particular the accuracy of fit of the impressions and the web tension of the printing material can be favorably influenced.

A preferred application of the method according to the invention is the correction of a longitudinal register deviation, wherein the position change is performed as a cylinder correction in the form of a correction of the cylinder angle position. In this form, the process can be used for rotary printing presses to eliminate longitudinal register deviations.

Further advantages and embodiments of the invention will become apparent from the description and the accompanying drawings.

It is understood that the features mentioned above and those yet to be explained not only in the particular combination given, but also in other combinations or alone, without departing from the scope of the present invention.

figure description

In the following, the invention and in particular its advantages with reference to an embodiment shown in the figures will be explained in more detail.

Figur 1

eine schematische Seitenansicht einer Ausführungsform eine erfindungsgemäßen Vorrichtung; und

Figur 2

eine schematische Darstellung einer bevorzugten Ausführungsform des erfindungsgemäßen Verfahrens.

It shows

FIG. 1

a schematic side view of an embodiment of a device according to the invention; and

FIG. 2

a schematic representation of a preferred embodiment of the method according to the invention.

Detailed description of the figures

In FIG. 1 a preferred embodiment of the device according to the invention is designated overall by 100. A printing material, for example, paper 101 is fed to the machine via a feed unit 110. The paper 101 is guided and printed by printing units 111, 112, 113, 114 and re-issued by a pull-out unit 115. The input, extraction and printing units 110 to 115 can be positioned, in particular cylinder or angularly correctable, arranged, which is indicated by semicircular arrows 103. For clarity, not all arrows are provided with reference numerals.

The printing units 111 to 114 each have a printing cylinder 111 'to 114', against which a respective impression roller 111 '' to 114 '' is made with strong pressure. The printing cylinders 111 'to 114' are individually and independently driven, the impression rollers 111 '' to 114 '' are freely rotatable. The pull-in and pull-out units 110, 115 each have two counter-rotating cylinders which guide the paper 101. The feed and withdrawal unit 110, 115 and the printing units 111 to 114 together with the continuous paper 101 form a frictionally connected unit.

In the web sections between the individual printing units 111 to 114, the paper 101 is guided over unspecified rollers and devices, which are designated 102. For reasons of clarity, not all rollers and devices are provided with reference numeral 102. In particular, these may be deflection rollers, drying devices, etc.

The web is provided between the infeed 110 and the first printing unit 111 with a sensor 120, which is designed as a web tension sensor. Web tension values F detected by the sensor 120 are supplied to a measured value evaluation device 130. Depending on the web tension values F supplied by the sensor 120, the positioning of the feed train 110 is controlled.

In the web section between the first printing unit 111 and the second printing unit 112, a sensor 121, in the web section between the second printing value 112 and the third printing unit 113, a sensor 122 and in the web portion between the third printing unit 113 and the fourth printing unit 114, a sensor 123 is arranged. The sensors 121 to 123 are designed as brand readers. During the passage of the paper 101, a mark reader 121 to 123 detects when the print mark (not shown), which is preferably applied by the first printing unit 111, reaches the mark reader and is respectively fed to a measured value evaluation device 131 to 133. Then, the position of the corresponding pressure cylinder 112 'to 114' is detected and also fed to the respective Meßwertauswerteeinrichtung 131 to 133. Each measured value evaluation device 131 to 133 compares the actual values of the cylinder position fed to it with predefined setpoint values and calculates therefrom a respective register deviation ΔR2 to ΔR4 (path / cylinder correction). The further processing of the identified registers is considered in addition to the FIG. 2 clear. The deviations are fed to the arithmetic units 210, 211, 212, 213 and used to position the printing units 111 to 113 and possibly also for the positioning of the feeding unit 110, as shown in FIG FIG. 2 is shown in more detail.

In FIG. 2 a preferred embodiment of the method according to the invention is shown schematically. The vertical dividing line A represents a schematic subdivision of the method Separation line A represents the control or regulation of the printing units, the area to the left of the dividing line A represents the control of the intake. As already explained, the control of the intake system is preferably carried out additionally.

The preferred embodiment of the method according to the invention is based on the example of FIG. 1 described device such that the misalignment or the register deviation is corrected by changing the position of all lying in the processing sequence before the respective processing device concerned or the printing unit concerned processing equipment or printing units. It goes without saying for the person skilled in the art how a corresponding correction can be carried out by changing the position of the respectively affected and all machining devices lying in the machining process after the machining device concerned.

In the first method step 201, those from the sensor 120 (FIG. FIG. 1 ) and the measured value evaluation device 131 to 133 ( FIG. 1 ) determined voltage values F and register deviations ΔR2 to ΔR4 the computer units 210 to 213 supplied. It goes without saying that all listed measured value evaluation devices 130 to 133 and computer units 210 to 213 can be realized centrally or locally (in the drive, motion control, SPS). The computer units 211 to 213 calculate from the supplied register deviations ΔR2 to ΔR4 the angle corrections ΔΦ2 to ΔΦ4, which are necessary for repositioning the respective printing cylinder 111 to 113.

In method step 202, the determined angle corrections ΔΦ2 to ΔΦ4 are fed to summation units 220 to 223. It is understood that in an analogous manner, more than three register deviations can be detected, which is indicated by the dashed line and the three dots.

In order to change the registration of the impression cylinder 114 ( FIG. 1 ), the angular position of the printing cylinders 111 to 113 is changed according to the illustrated embodiment. For this purpose, the angle correction ΔΦ4 calculated by the computer unit 213 is supplied to all preceding printing cylinders via their summation units 221 to 223, in the illustrated preferred embodiment also to the intake unit 110 via its summation unit 220. Similarly, to correct the register deviation ΔR3 of the printing unit 113, the angle correction ΔΦ3 calculated by the computer unit 212 is supplied to the summation units 220 to 222. The angle correction ΔΦ2 is finally supplied to the summation units 220 and 221.

The summation units 220 to 223 respectively calculate the total angular displacement ΦEZW, Φ1 to Φ3 to a master axis position indicated by ΦLA. In method step 203, the respective angular offset values are calculated together with the value of the master axis position and transferred to the corresponding intake and printing units or their adjusting devices (not shown).

In method step 204, the infeed unit 110 and the printing units 111 to 113 are repositioned according to the calculated values in order to correct the register deviations. By the described method, a Register deviation for each printing unit are corrected almost simultaneously. In contrast to a correction in the prior art, it is not necessary in a printing press according to the invention to correct the register deviations individually and successively, since a coupling of the printing units to one another is reduced.

It is understood that in the illustrated figures, only a particularly preferred embodiment of the printing machine according to the invention is shown. In addition, any other embodiment, in particular by a different arrangement or number of printing units, structure of the etc. conceivable without departing from the scope of this invention.

LIST OF REFERENCE NUMBERS

100

press

101

Substrate (paper, foil, sheet metal)

102

Guide rollers, guide rollers

103

angle correction

110

infeed

111, 112, 113, 114

printing unit

111 ', 112', 113 ', 114'

pressure cylinder

111 '', 112 '', 113 '', 114 ''

impression roller

111 '', 112 '' ', 113' '', 114 '' '

drives

115

excerpt

120

Web tension sensor

121, 122, 123

mark reader

130, 131, 132, 133

Messwertauswertevorrichtung

201, 202, 203, 204

step

210, 211, 212, 213

computer unit

220, 221, 222, 223

Summation unit

A

subdivision

F

Web tension value

.DELTA.F

Web tension deviation

ΔR2, ΔR3, ΔR4

register deviation

ΔΦ2, ΔΦ3, ΔΦ4

angle correction

ΦEZW, Φ1, Φ2, Φ3

angular displacement

ΦLA

Master axis

Claims (8)

1. Drive system for a web-fed printing press (100), in particular a shaftless gravure printing press, having a plurality of individually driven printing units (111 to 114) which are provided with longitudinal register adjusting devices,
   characterized by
   means for the common setting of all the longitudinal register adjusting devices of all the printing units (111; 111, 112; 111, 112, 113) located upstream of a first printing unit (112; 113; 114), and of a feed unit (110) in order to correct a register deviation (ΔR2, ΔR3, ΔR4) at the first printing unit.
2. Drive system for a web-fed printing press (100), in particular a shaftless gravure printing press, having a plurality of individually driven printing units (111 to 114) which are provided with longitudinal register adjusting devices,
   characterized by
   means for the common setting of the longitudinal register adjusting devices of the first printing unit (112; 113) and of all the printing units (113, 114; 114 located downstream of the first printing unit (112; 113), and of a delivery unit (115) in order to correct a register deviation (ΔR2, ΔR3, ΔR4) at the first printing unit.
3. Drive system according to one of the preceding claims,
   characterized by
   at least one longitudinal register adjusting device for carrying out a cylinder correction.
4. Drive system according to one of the preceding claims,
   characterized by
   detection devices (121, 122, 123) for detecting the register deviation (ΔR2, ΔR3, ΔR4), each detection device being assigned to a printing unit (112, 113, 114).
5. Drive system according to one of the preceding claims,
   characterized by
   means for carrying out a web/cylinder or a web/web method for determining a register deviation (ΔR2, ΔR3, ΔR4).
6. Method for correcting a register deviation (ΔR2, ΔR3, ΔR4), a material web (101) being treated in successive treatment steps (110 to 115), the register deviation (ΔR2, ΔR3, ΔR4) of the material web with respect to a first treatment step (111 to 115) being corrected,
   characterized in that
   the register deviation (ΔR2, ΔR3, ΔR4) is corrected by a position change of all the treatment steps (110; 110, 111; 110, 111, 112; 110, 111, 112, 113; 110, 111, 112, 113, 114; 110, 111, 112, 113, 114, 115) located upstream of the first treatment step (111; 112; 113; 114; 115) in the treatment sequence, which are carried out by printing units (111 to 114) and a feed unit (110), or by a position change during the first treatment step (111; 112; 113; 114) and all the treatment steps (112, 113, 114, 115; 113, 114, 115; 114, 115; 115) located downstream of the first treatment step in the treatment sequence, which are carried out by printing units (111 to 114) and a delivery unit (115).
7. Method according to Claim 6 for use in conjunction with a gravure printing press.
8. Method according to Claim 6 or 7,
   characterized in that
   the register deviation is a longitudinal register deviation (ΔR2, ΔR3, ΔR4), the position change being carried out as a cylinder correction.

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