EP0705171A1

EP0705171A1 - Process and arrangement for controlling or regulating operations carried out by a printing machine

Info

Publication number: EP0705171A1
Application number: EP94921626A
Authority: EP
Inventors: Helmut Kipphan; Wolfgang Geissler; Gerhard Fischer; Werner Huber; Bernd Kistler; Gerhard Löffler; Anton Rodi; Harald Bucher; Clemens Rensch
Original assignee: Heidelberger Druckmaschinen AG
Current assignee: Heidelberger Druckmaschinen AG
Priority date: 1993-06-25
Filing date: 1994-06-27
Publication date: 1996-04-10
Anticipated expiration: 2014-06-27
Also published as: EP0884180A1; EP0884182B1; DE4321179A1; US6050192A; DE59410074D1; WO1995000336A2; EP0884182A1; DE59409945D1; EP0884179B1; EP0884180B1; DE59410234D1; DE59409943D1; EP0884181B1; DE59409900D1; EP0884179A1; EP0884178A1; DE59409944D1; EP0705171B1; US6119594A; EP0884178B1

Abstract

A process and arrangement are disclosed for controlling or regulating operations carried out by a printing machine. The object of the invention is to develop a process and arrangement which help and supplement the operator during a quality control, which allow a representative colour measurement site to be manually or automatically selected, which ensure a rapid regulation, reduce the amount of spoilage, the complexity and the costs of the control or regulation of operations carried out by a printing machine. For that purpose, co-ordinates for the measurement site examined by a picture recorder (15, 16) are determined from picture information which reproduce at least the surface of a printed object (2). The picture recorder (15, 16) detects a measurement field of defined size of the surface of a printed object (2) at each measurement site. The invention is particularly suitable for printing machines having devices for handling, printing and processing sheets of paper or other surfaces to be printed. In addition, the invention may be used to control or regulate devices mounted upstream or downstream of a printing machine, such as devices for separating, folding, cutting, collecting, stacking, annexing, including, sorting and filing sheets or webs.

Description

Method and device for controlling or regulating operating processes of a printing machine

description

The invention relates to a method and a device for controlling or regulating operations of at least one printing machine. The invention is particularly applicable to printing presses _/ which contain devices for handling _/ printing and for treating sheets or other surfaces to be printed. Furthermore, the invention can be used to control or regulate devices _/ which are upstream or downstream of a printing press _/ such as devices for separating _/ folding _/ cutting _/ collecting _/ stacking _/ inserting _/ inserting _/ sorting and depositing sheets or webs. Further areas of application are machines and devices for the bookbinding production and further processing of printed products as well as devices for inspecting printed products _/ which, among other things, permit a graphic representation of the surface and / or a quality assessment of the printed products. The invention is used to control and regulate operating processes _/ which significantly influence the shape and / or coloring of a sheet _/ web or a printed product.

State of the art are methods and devices for controlling and regulating operating processes on printing machines _/ which cutting and folding devices are subordinate. In order to control and taper the coloring and the cutting and folding register, when transporting a sheet or a web through the printing units, in addition to an actual printed image, colored ones are printed on the surface of the printing material Print control strips _/ register crosses and other register markings generated.

For color control it is known _/ to obtain actual values for color control on the basis of color measurements in color fields of a specific color of the print control strip. It is also _/ known _/ win especially for jewelery and special colors _/ actual values for the color control of printed in full colors image areas. The color measurement in the color fields or in the solid image areas can be carried out inside the printing press or offline outside the printing press _{/ for} which purpose a test sheet is removed from the process and fed to a color measurement arrangement. The preferably optoelectronically obtained color measurement values can be passed on to a control and regulating circuit _/ where they are compared with setpoint values and converted into manipulated variables for control elements of a color distribution device.

Devices are known for register setting _/ which have register mark sensors operating online _/ which are directed to register marks printed in register mark tracks. There are also offline working facilities _/ where the register accuracy of register crosses is measured with a register cross reader and the measured values are then passed on to the machine control in question _/ where manipulated variables are generated for the register setting devices.

A disadvantage of these solutions _/ that the measuring points for the actual determination of are predetermined to be controlled or to be regulated by the operating variables serving for quality assurance color measuring fields, register marks and register marks. The production of these measurement marks creates a considerable effort in the prepress stage. The accuracy of such color measurements and register crosses is limited by assembly _/ opiei and development errors in the prepress stage. Furthermore, the print control strips and register marks _/ which do not belong to the actual print image _/ limit the area available for the print image on the printing material. The color measurement fields of a pressure control actual tire _/ which is generally arranged upstream or downstream of the actual print image in the transport direction of the printing material _/ are only representative of the print image to a limited extent. The offline color measurements delay the color control process _/ whereby a lot of waste arises until the adjustment to an OK state. Undefined drawing times _/ especially when the press is not in a steady state _/ lead to problems _/ such as e.g. B. overshoot in color control. Furthermore, the previous solutions regarding the choice of the color measurement location are inflexible. A subject-dependent color measurement location by the operator of the printing press is not provided in the solutions according to the prior art. Furthermore, the offline color measurement means that the operator is concerned with the handling of the measurement objects and the coloring and register measuring device over a longer period of time. The operator therefore has no complete information about the trend of the color and register settings.

Since recovery value must be provided for the various to be controlled or to be regulated operations each separate sensors for _/ increase the effort and the cost of controlling and regulating the same time more than two operations.

The object of the invention is to develop a method and a device _/ which supports and supplements the operator in quality assurance, which enable a selection of a representative color measurement location either by hand or automatically _/ which enables fast control guarantee _/ which reduce the amount of waste and which reduce the effort and costs for the control or regulation of operating processes of a printing press.

The object is achieved according to the invention by a method _/ in which image information _/ which at least reproduce the surface of a printed product _/ coordinates for the measuring locations of an image recording device are determined. At each measuring location, the image recording device detects a measuring field of a defined size from the surface of a printed product.

The device according to the invention for controlling or regulating operations of a printing machine _/ with which the method can be carried out _/ consists of at least one image recording device _/ which is directed at the surface of the printed product and which is connected to a control and regulating circuit. The control and regulating circuit can be supplied with image information _/ which reproduce the surface of the printed product. The control and regulating circuit is connected to actuators to influence the operating processes within the printing machine.

Embodiments of the invention result from the subclaims.

The effect of the invention will be described in the following:

The coordinates for the measuring locations of the image recording device are first determined from the image information representing the surface of a printed product by means of the control and regulating circuit. The image information for determining the coordinates can be from various sources come from. A first possibility is _/ that the image information is taken from the image recording device _/ which is arranged in the printing machine and which is directed to the surface of a printed product for scanning. For this purpose, the entire surface or only partial areas thereof can be scanned.

If the printing machine is a printing press _/ and the image recording device is preferably directed towards the surface of a sheet or web following a last printing unit _/ then the image information for determining the coordinates for the measuring locations can be obtained from a print image generated in the setup phase. Since the image recording device not only captures the printed image _/ but also the remaining area of the sheet or a web _/ it is possible _{/ to use} the method and the device for the purpose of material identification or material testing of the printing material _/ in particular for determining the whiteness or the luminance level or for determining of color variations or material defects _/ such as spots or holes _/ use.

If the printing machine is designed exclusively for the inspection of printed products _/ then the image information _/ with the aid of the image recording device _{/ can be obtained} from the surface of any printed product to be inspected.

Another possibility _/ coordinates to determine the measurement locations _/ is _/ are used that image information _/, the image pickup means be taken _/ the scans an image of the surface of the printed product outside the technical printing machine. Further possibilities result from _/ that the image information is generated with the aid of a digital computer _/ which is part of a device for image generation, or that it already exists available image information rather from a data spree.

The selection of a suitable measuring location for a specific operating process can be done with the aid of a computer _/ which can be arranged within the control and regulating circuit. If, for example, the color scheme _/ the dampening solution guide and the register are to be regulated or controlled in an offset printing press _/ then coordinates for the measuring locations of each of these operating processes are determined.

A program runs in the computer _/ which finds the suitable measuring locations. For color control of a printing press, e.g. B. from the image information measurement locations are automatically determined _/ which are in a color control Is rei fen and / or which are in the printed image itself. Said program ensures _/ that the measuring point significantly determine the actual value of one or more defined colors. A measuring point is significant for a color control of a printing press _/ if it contains as much color information as possible for the respective color. Suitable measuring points for the color control are found, for example, within dark gray areas. In the case of decorative and special colors, the measuring points are in standalone colors _/ preferably in the 3 / A tone range anyway. Particularly critical tones can be taken into account when determining the measuring points _/ so that, for example, the measuring point is depicted in a subject _/ in the furniture, in a brown tint Area or is determined in a flesh-colored area in a portrait. The information about _/ which is the critical color tone for the respective print _/ can be entered in advance for the device according to the invention.

For a moisture control, such significant measuring locations are determined _/ which, in color-free areas in the scanning direction, lie behind 3/4-tone areas or full-tone areas. Suitable measuring locations for register control can arise in the printed image with register cross-like structures _/ such. B. thin lines and sharp edges _/ as they are for example when imaging masts _/ antennas or windows in a subject.

In a further step, to obtain the actual value, the printed products are scanned at the predetermined measuring locations with the aid of the image recording device arranged in the printing machine. The actual image signals are fed to the control and regulating circuit _/ where they are compared in a comparator with setpoints from a reference variable encoder. For each operating process to be controlled or regulated, separate actual values are determined at defined measuring locations and compared with separate target values. Only one image capturing device is required for each printing machine to obtain the actual value for all operating processes to be regulated or controlled. The control and regulating circuit can contain separate devices _/ comparators and reference variable transmitters for each operating process. It is possible _/ that there is provided a common Steuei- and control circuit for a plurality of in each case provided with an image pickup device to the printing process machinery _/ in which case a switching device receiving the actual image signals from the individual imaging devices and the distribution of the control signals to the individual actuators for influencing operating parameters takes over. In any case, the control and regulating circuit outputs control signals _/ which influence the respective operating process in the desired manner.

The control and regulation Lscha Itung can be accommodated in an operating console and can be implemented in conventional analog and digital circuit technology or with fuzzy logic. The operator can control and Control circuitry interact _{/ for} which the control console can be assigned a computer with a high-resolution screen _/ with an alphanumeric keyboard _/ with a cursor control device and with an input and output device for data.

The image of the surface of a printed product, including the measuring locations determined by the control and regulating circuit, can be displayed on the screen _/ and the measuring locations can be specially marked. Similarly, an actual image _/ a difference image _/ measured values of operating variables and manipulated variables can be displayed on the screen. The operator has the possibility _/ to intervene in the control or regulation of the operating processes _/ by changing the coordinates of the measuring locations _/ the setpoints of operating variables or the manipulated variables.

The image recording device can be directed to a printed product which is guided in one plane or to a printed product which is transported on the lateral surface of a cylinder. In this way it is possible _/ not only to control or regulate the operating processes as a function of image signals _/ which originate from the surface of the printed product _/ but also as a function of image signals _/ which originate from the surface of the devices transporting the printed products. An example is a gripper control _/ which uses the image signals _/ which contain the position of the printed product relative to the grippers holding the printed product in the transport devices _/ which controls the gripper opening times. As

Image recording devices can be used with all image sensors suitable for photometric measurements _/ such as, for example, discrete color-selective photodiodes and transistors _/ line and matrix-shaped CCD light receivers or

Color picture tubes. The working wavelength depends on the type of image sensors used _/ so that both Heat radiation _/ IR radiation, visible light or UV radiation can be used as the radiation containing the image information. The image recording device can work in the reflux mode or in the transparency mode. The angle of incidence and angle of exit for the measuring light is adapted to the reception characteristics of the image sensors. The image recording device is suitable _/ to scan the entire width of the printed product. An advantageous variant consists wherein image signals of the actual print image but also signals of register marks or register marks, and the areas between the print image and the edges _/ abut _/ of the printed product at the same time in a measuring bar _/ is arranged over the entire width of the printed product _/. If necessary, individual image sensors can be desensitized. Another design variant results from an image recording head which is arranged transversely to the direction of transport of the printed product _{/ for} which purpose the image recording head is coupled to a positioning device including a drive, length and angle measuring system. In this way, the image recording device can be directed onto a defined scanning track _/ in which significant picture elements or the register marks are contained. The change in the scanning angle, like a focusing movement, can be automated with the aid of separate control devices _/ so that an optimal signal-to-noise ratio is always achieved. It is possible _/ an arrangement _/ caused by highlight for compensating for errors _/ provide _/ the image sensors are connected upstream, for example in the form of crossed linear polarizers.

Further advantages of the invention are to be described on the basis of the control or regulation of operating processes on a printing press: It is a particular advantage of the invention _/ that it can be used very flexibly with the aid of the image recording device described above for print quality assurance. The main application in a printing press is simultaneous image inspection and color control _{/ for} which purpose the image recording device records color measurement values directly from the printed image. The color measurement values are preferably obtained photometrically using the three-range method or with the aid of a spectral measuring device. The spectral sensitivity of the measuring channels arranged in the image recording device for each area corresponds to the spectral value curves of a normal observer. The image sensors themselves can have a defined spectral sensitivity, or image sensors with essentially the same sensitivity are adapted to the spectral value curves of the normal observer with the aid of filters. The image sensors can e.g. B. arranged in a row scan the printing material zone by zone _/ whereby the zone width can be variable _{/ for} which purpose signals from image sensors can be correspondingly detected in groups. The scanning zones can correspond to the zones _/ which are predetermined by the color distribution device of the printing press. If there is no suitable measuring location for one or more colors in a scanning zone due to the subject, then measured values from neighboring zones can be used for color control. It is possible _/ to capture the complete print image using the image recording device. However, only a part of the printed image can be scanned. A special device ensures that the same scanning location is recorded in each print copy. For this purpose, stored image measurement values can be taken from previous measurement cycles, which makes it possible to identify the scanning location. As described above _/ signals for determining the scanning location _/ off means relative to the measurement of the position of the printing of a reference map used _/ are supplied to the control circuit _/ so that a correlation of the Lagemeßwerte occurs to the image signals. To avoid under- or over control of the image sensors in high-contrast print images _/ may be preceded by the receivers a light attenuator arrangement. Furthermore, the intensity of the measuring light can be regulated depending on the speed of the printing material or on the contrast at the measuring location _{/ for} which purpose appropriate devices for speed measurement or for contrast measurement must be connected to the measuring light source. The speed can be obtained from the signals of an incremental rotary encoder _/ which is coupled to the cylinders which convey the printing material.

When used in the image pickup device as a photoelectric receiver CCD line or matrix _/ then, with the aid of the signals of the incremental encoder are fed _/ the integration time of the CCD receiver elements in dependence on the speed of the printing substrate or the printing machine of a timer circuit _/ to be changed.

In the same way, the image recording device can also detect a print control strip which is also printed outside the actual print image. The print image sensors are then initiated exactly at the time of passing the print control strip. In one variant, signals can be obtained from the actual printed image as well as from the print control strip using the image recording device.

Another application of the invention is _/ that some of the members of the device elements used for image inspection. This enables overall quality control to be achieved. For this purpose, the image recording device is used as an online measuring arrangement. As with online color measurement, one becomes Comparison of the actual image data with reference values, gross color deviations and register errors _/ toning _/ sliding and duplicating, among other things, errors determined and displayed on the screen. Furthermore, due to the image inspection that covers the entire printing material, errors in and on the printing material _/ such as. As cracks _/ holes _/ edge irregularities of the printing _/ inclusions _/ slugs and printing errors by other mechanical external influences recognizable. Wherever possible, the signals from the comparison resulting from the image inspection are fed to control elements of the printing press to influence various operating processes and / or are fed to devices _/ which are used for display and / or for quality documentation.

An example of the image inspection is the monitoring of the damp guidance in an offset printing machine. For this, e.g. B. the image data obtained with the image recording device from the area of the start of printing can be continuously evaluated over the entire width of the printing material. If the evaluation result in _/ that the lubricating limit is reached _/ then the fount Ivertei lungseinri be chtungen and optionally the Farbvertei Lungseinri chtungen adjusted so _/ that the ink / fount l-sliding chgewi CHT an optimum continuous printing allowed.

Another example of image inspection is the monitoring of the coating and powder application on the substrate. For this purpose, the image recording device is designed as a gloss measuring device. It is possible _/ to provide a separate highlight source for gloss measurement _/ which shines on the substrate at a defined angle of incidence. It is also possible _/ to evaluate light for specular light measurement with the aid of at least one receiver arranged in the image recording device _/ whose plane of incidence and failure is not in the transport direction of the printing material. The wherein the light incident on a receiver side light is detected for the Farbmesung or used for image inspection serving light source and receiver arrangement _/.

Another application of the invention in a printing press is register control. Actual image signals from register crosses _/ register marks or from other image elements that are significant for the register are evaluated and compared with target image signals.

A register control device outputs signals to register setting elements which cause a correction of the register with respect to one another both with regard to the position of the image on the edges of the printing material and with respect to the individual color images.

With the help of the press control, a selection can be made from the applications described above. It is also possible _/ not to take all measurements on every print image. For reasons of data processing, it may be advisable _/ for example to carry out the image inspection on each printed copy _/ while the color and register measurements are carried out on every second or nth printed copy and / or averaging over several printed copies is carried out. It is also possible _/ the number of measurement locations to change on a print copy and the frequency of the measurements to a measurement location. You can also switch between these applications depending on process variables. For example, if the deviation lle in one of Anwendungsf is too high _/ then the press control can ensure _/ that very many actual values are generated by the imaging device in this application. Such a case can exist, for example, when the printing press starts up or in the event of deviations due to duplication. To transmit the signals representing the image, an optical image guide can advantageously be used _/ the light entry surface of which is subdivided into partial areas _/ the partial areas receiving light from the printing material from individual scanning zones. Photoelectric receiver elements are then provided on the light exit surface _/ which are each assigned to one of the scanning zones and which convert the luminous flux into electrical signals.

In any case, the signals generated by the image recording device are fed to a device for processing the image signals. The transmission of the image signals between the image recording device and the processing device can also take place wirelessly without an image conductor cable _/ if the information recorded by the image sensors is transmitted via an electromagnetic _/ acoustic or optical transmission and reception link. Such a transmission path is unnecessary _/ if the processing device is locally assigned to the image recording device. Depending on the operating mode of the image recording device, the device for processing the image signals permits data reduction _/ so that an optimal control time is guaranteed.

The processed image signals are fed to the comparison device and compared with reference signals _/ which can be obtained from a reference variable encoder. A memory can be used as the reference variable _/ which contains target image data _/ which originate from an earlier print job for the same print image. It is also possible _/ that the memory contains target image data _/ which are obtained from the measurement of a good sheet with all colors and / or from individual color extracts of a good sheet. This measurement only needs to be carried out once _{/ for} which the press control can contain a program which, on a control signal, provides the required color separations delivers and initiates the measurements. From the measured values corresponding to the grid, z. B. calculates the area coverage of the individual colors and stores them together with the color target values from the color measurement on the good sheet in the memory. The remissions of the individual colors can also be measured and stored _/ whereby the conventional _/ empirical determination and storage of color tables is eliminated. That kind of

Reference size preparation is particularly advantageous when printing with more than the four process colors _/ cyan, magenta, yellow and black _/ whereby only one image recording device is required for a printing press. To increase the accuracy of the calculation when solving the Neugebauer equation used for this purpose, color separations for any color combination can also be used. B. Black / Cyan; Black / magenta; Black yellow; Cyan / magenta; Cyan / yellow and magenta / yellow _/ printed, measured and their remission stored.

The production and measurement of color separations is also useful for calculation methods that do not know the area coverage, e.g. B. only works with remissions or colorimetric or density values determined from them. This possibility of providing reference values is therefore not limited to determining the area coverage and can provide all the necessary knowledge about individual colors and their various combinations.

Another possibility of providing reference variables is that the reference signals are taken from an image measuring device on which a correct template has been scanned. The image measuring device arranged offline and the image recording device arranged online can be of the same design. As a template, partial images of a template that is true to the original can also be scanned, and then for positioning the partial images as they are on the should be arranged according to the correct template, layout signals can be fed to the reference variable generator.

A further possibility of providing reference variables results from the fact that the operator of the printing machine then sends a signal for data transfer to the reference variable generator when the operator visually and on the basis of measured values makes the decision that the printing machine has run into a quality-appropriate production status. In this case, the processed actual image signals are transferred to the reference variable encoder as setpoints.

In a variant, a device can be provided which evaluates the time intervals and amounts of the control signals given interactively by the operator. If the distances between the control signals and the amounts fall below threshold values, then a signal for the okay state can be generated with this device. As a result of this signal, the actual values can be adopted as target values, so that the process conditions that are currently correct in the printing process are frozen until the operator of the printing press gives the above-mentioned signals to the control circuit at shorter intervals.

Furthermore, the reference signals Le can be taken from a setpoint value memory which is assigned to the control device of the printing press. All storage media customary in data processing, e.g. B. semiconductor memory, floppy disks, magnetic tapes and optical storage _/ can be used. The reference signals can be corrected or changed by the operator by hand. Similarly, the operator has the option _/ reference signals to globally change percentage.

If the result of the comparison between desired and actual values differ, the output signal from a limit _/ then an error signal is generated and output. A variant is _/ that an acoustic signal is output. If a computer with an alphanumeric keyboard and cursor control device _/ as well as with a screen is provided for the interaction of the operator with the machine control and with the color controller _/ then the error signal can be generated optically on the screen _/ whereby the actual image and the specially marked faulty image areas can be displayed. The markings of the defective image areas can, for example, be simple geometric figures or can be implemented in the form of a visually clearly visible false color representation. In addition to the pictorial representation of the error may then _/ if the control circuit logi an error detection assigned k _/ the fault can be determined from the processed image signals and from the signals according to the comparison means and is also outputted on the screen. The errors can be inter alia in the following error types classify: color errors _/ register error _/ Feuchtungsfehler _/ slugs, imperfections in the substrate _/ impurities in the substrate and Randausbruch in the substrate. The control device can be blocked depending on the output signal of the error detection logic. In this way it is possible _/ that, for example, a defect or an impurity in the substrate have no effect on the color scheme. It is also possible _/ to check the actual values for the control device for plausibility and suitability for color control and image inspection _/ by calculating the scatter of the measured values of pixels for the color measurement and monitoring for exceeding a limit value.

Exceeding the limit of the difference between the target and actual image values can also result in a sheet-fed printing machine _/ that the incorrectly printed sheets are discarded at a waste paper lock _/ alternatively using a marking device _/ such as a Ink-jet printing device _/ can be provided, which identifies the faulty sheet or parts of the respective sheet.

In order to monitor the quality of a print job, the actual / actual deviation can be documented at intervals. For example, one described above

Marking device to be used _{/ to} print every 50th sheet or printed image with a serial number _/ the time of measurement and the amount of the target / actual deviation. In the case of a sheet-fed printing machine, a strip insertion device on the delivery tray can be operated at the same time. In addition, the quality-documenting data printed on the sheets can be saved and, if necessary, output as a log with error statistics. The logged measurement data of the test sheets can be checked again outside the printing press with the aid of a calibrated color difference measuring device, preferably at homogeneous measuring locations of the printed image. The invention will be explained in more detail with reference to drawings.

Show it:

1 is a diagram of a control or regulating device according to the invention for a printing press _/

2 an image recording device with four different imaging systems _/

3 an image recording device with exactly one optically imaging system _/

4 an image recording device with a lens array, 5 shows a diagram for signal acquisition on a cylinder on a sheet-fed printing machine _/

6 an optoelectronic signal processing _/

Fig. 7 is a scheme for the correction and

Color value signal storage of image signals _/

8 shows a diagram for the differential image evaluation.

In the scheme of a color control system according to the invention shown in FIG. 1, a web 2 for printing on both sides is conveyed by printing units Z, 4 of a web-fed rotary printing press 5 with the aid of drive elements 1. The printing _3/4 contain Farbvertei lungseinri chtungen 6, 7, _8/9, containing conventional zonal Farbdosi ere ELEMENTS rect and in the transverse direction to the web 2 Transportri 10 generate a color profile. The web 2 is printed on both sides multicolored in one pass through the rotary printing machine 5 in contact with pressure set to blanket cylinders _{_11/12/13} _/ 14th The last printing unit 4 are next provided on the upper and lower sides of the web 2 per an image pickup device _15/16 _/ which are pivotable in bearings _17/18 and in guides _19/20 perpendicular to the transport direction 10 slidably. The image pickup devices _15/16 cover the entire width of the web 2 and each containing at least a light source _21/22, and a plurality of photoelectric receivers 23 _/ 24. In order to detect the rotation speed and the rotation angle of the blanket cylinders _{_{_11/12/13/14}} as well as the transport speed the lane 2 is _{_{_11/12/13/14}} coupled to an incremental rotary encoder 25 one of the coupled via a gear train blanket cylinder. The phase of the blanket cylinder _{_{_11/12/13/14}} is variable with the aid of Registereinstellvorrichtungen _{_26/27/28} _/ 29th All to control and regulate the operations of the Rotary printing press 5 necessary elements are connected to a machine control 30, which is arranged in a control panel 31. The machine controller 30 contains input and output points 32 for control and regulating signals. The connections and arrows shown in FIG. 1 to the input and output points 32 schematically show the information flows and their directions. Furthermore, the machine control 30 contains the hardware and software as well as at least one control circuit 33. The control circuit 33 includes, among other things, a device 34 for processing the image signals, a comparator 35, a reference variable generator 36, a control device 37 and an error detection logic 38. The device 34 for processing the image signals is connected to the photoelectric receivers 23, 24 of the image recording devices 15, 16. The output of the device 37 for processing the image signals is connected to an actual value input of the comparator 35, a setpoint input of the comparator 35 being connected to the reference variable generator 36. The output of the comparator 35 is connected to an input of the error detection logic 38 and the control device 37. A control output of the error detection logic 38 is connected to a blocking input of the control device 37. The output of the control device 37 is via an output point 32 with the color metering elements in the

Color distribution devices 6, 7, 8, 9 connected. The output of the control device 37 can also be connected to the register setting devices 26, 27, 28, 29. A computer 39 with a screen 40, a keyboard 41 and a cursor control device 42 is arranged on the control panel 31. The bus system of the computer 39 is fed into the machine control 30 via a further input / output point 32. On the bus system are data from an external image measuring device 43, data from a computer network 44 of the print shop and data from one Dial-up modem 45 as well as the output data from the comparator 35 and the error detection logic 38 can be viewed. The dial-up modem 45 is connected to an external transmission and reception unit 46. An acoustic signal generator 47 is connected to the machine control 30 at an output point 32.

The mode of operation of the color regulator shown schematically in FIG. 1 will be described below:

Corresponding to the number of color zones, which are determined by the color distribution devices 6, 7, 8, 9, a plurality of light sources 21, 22 are provided in the image recording devices 15, 16 evenly distributed along the line over the width of the web 2. With the help of elliptical mirrors, the light is thrown onto the web 2 at a defined angle of incidence. Each individual light source 21, 22 is controlled by a programmable current source, so that the color temperature of the light sources 21, 22 can be regulated. For this purpose, the actual luminous flux of each light source 21, 22 can be detected with the aid of optical fibers. The measuring light reflected by the web 2 can be transmitted to the photoelectric receivers 23, 24 with the aid of an optically imaging system. The luminous flux emanating from a picture element of the path 2 is proportional to the signal charge of a photodiode of a CCD line used as a receiver 23, 24. For calibration and adjustment, the image recording devices 15, 16 can be displaced perpendicular to the direction of transport 10 and can be pivoted about the bearings 17, 18. Focusing and error compensation of the image recording device 15, 16 can thus be achieved. In a pivoted-out position of the image recording devices 15, 16, the calibration can be carried out on the basis of a color standard. It is also possible that the Image recording devices 15, 16, the light source 21, 22 or the photoelectric receivers 23, 24 or only parts thereof are arranged displaceably in the direction of the optical axis. Since the color measurement in the printed image is carried out according to the so-called three-range process, it is necessary due to the different spectral properties of the optical measuring means and the photoelectric receiver 23, 24 in the individual color zones to provide spectrally matching components in the measuring beam path. One method for the spectral adjustment consists in providing correction filter glasses in addition to the main filter necessary for the implementation of the three-stage process. Another method uses partial filters in which a large number of different color filters are cemented or sputtered onto neutral glass. The areas of the individual color filters are switched on or off by additional use of diaphragms and masks, so that the spectral course can be influenced. In a simple arrangement, four partial filters cemented onto a carrier plate are positioned over a circular screen using a cross slide. To avoid temperature errors, the color filters and photoelectric receivers 23, 24 can be kept at a constant working temperature with a thermostat.

FIG. 2 shows an image recording device 15, 16 with four different imaging systems 48, 49, 50, 51, in which color filters 52, 53, 54, 55 are arranged facing web 2. For the adjustment of CCD sensors 56, 57, 58, 59 acting as receivers 23, 24 relative to the imaging systems 48, 49, 50, 51, the CCD sensors 56, 57, 58, 59 are coupled to adjustment elements 60.

In the variant shown in FIG. 3, only one optically imaging system 61 is provided, the Color filters 62, 63, 64, 65 are combined to form a block. A protective glass 66 is provided in front of the color filters 62, 63, 64, 65. Four-way CCD lines 67 are provided as receivers 23 and 24, which are arranged on a common adjusting element 68. With this optical arrangement, different image elements 69 are imaged on the quadruple CCD lines 67 during a color measurement in the individual spectral ranges, so that the color measurement values belonging to one image element 69 are obtained at different times. The distance between the image elements 69 of the CCD lines 67 and the optical properties of the optically imaging system 61 are matched to one another.

FIG. 4 shows an image recording device 15, 16 with a lens array 70. The image information weighted by the color filter 71 is coupled into a picture conductor 72 with the lens array 70. The optical imaging system 73 located at the output of the image conductor 72 brings the image information to a CCD sensor 74 which is coupled to adjustment elements 75. The optical imaging system 73 can also be dispensed with if the glass fibers of the image conductor 72 are coupled via a fiber optic window or directly to the CCD sensor 74. This optical arrangement must be provided separately for each process color used.

FIG. 5 shows a diagram for an actual signal acquisition on a cylinder 76 of a sheet-fed printing press. The receiver modules 77 arranged over the width of the cylinder 76 are connected to the device 34 for processing the image signals. The also modularly constructed light sources 78 are connected to a device 79 for regulating the amount of light, which is also housed within the machine control 30. To synchronize and to provide a preprocessing cycle is within the Machine control 30, a synchronization device 80 and a timer are provided, which are connected to an incremental encoder 81.

For one equipped with CCD sensors 74

Image recording device 15, 16, the signal processing within device 34 is to be described below:

As shown in FIG. 6, the electrical image signals generated by the CCD sensors 82 are successively fed to an amplifier 83, a sample-and-hold circuit 84 and an analog-digital converter 85. The output of the analog-digital converter 85 is connected to a digital processing unit 86, which u. a. the function of the control circuit 33 described in FIG. 1 takes over within the machine control 30.

FIG. 7 schematically shows the correction of the image signals and the color value signal storage and FIG. 8 shows schematically the difference image evaluation within the processing unit 86. From the analog-digital converter 85, the digital image signals arrive at a first correction element 87 equipped with storage units. This correction element 87 contains a look-up table for linearizing the characteristic curve of the converter elements of the CCD sensors 82. The data required for this are obtained when the system is started up by a white value adjustment with different levels of control of the CCD sensors 82 and stored in the correction element 87 . The corrected image signals are fed to an input A of an accumulation unit 88. With the aid of the accumulation unit 88, different printing speeds are compensated for by controlled pixel-by-pixel addition in connection with a variation in the integration time of the CCD sensors 82. The subtotals are stored in a line memory 89 which is connected to an input B of the Accumulation unit 88 is connectable. In this way it is ensured that the brightest point in the image means that the CCD sensors 82 are still controlled sufficiently, for example at 50%, at the maximum speed of the rotary printing press 5. At the lowest printing speed, several measurements are possible within one measuring line, for example eight scans with full control of one line of CCD sensors 82, so that in this example a maximum compensatable speed ratio of 1:16 results. At the same time, the accumulation over n samples results in an improvement in the signal-to-noise ratio at low printing speeds. The accumulation takes place in such a way that the image data of the nth pixel present at the input A of the accumulation unit 88 for the kth scan, which was formed during the (k-1) scan, are read out from the line memory 89 and sent to the Input B of the accumulation unit 88 supplied subtotals are added. The new subtotal is then temporarily stored in a memory location n + 1. A timer 90 generates the addresses of the Zei Lenspei chers 89 and a list memory 91 from the pulses of the incremental encoder 25 and 81 and corrects the address offset arising during the accumulation, so that during the last accumulation of the line memory 89 and a within a measurement line Shadi ng memory contained in the list memory 91 tend to run synchronously. The timer 90 also supplies the control signals and the multiplex clock for the CCD sensors 82. For example, at a low printing speed, the data from eight lines of the CCD sensors 82 can be multiplexed onto the input of the correction element 87. The timer 90 is also fed signals about the thickness of the printing substrate 2, which are obtained with the aid of a thickness measuring device or which are already available within the machine control 30. These signals are linked to the signals of the encoder 25, so that the thickness of the Printing speed 2 dependent speed and position measured values for printing material 2 are corrected.

Furthermore, the processing unit 86 contains a multiplier 92, with the aid of which the accumulated image data from input A from a last accumulation of a measurement line and the reciprocal values of the standardized integration time at input B are multiplied.

A multiplier 93 connected downstream of the multiplier 92 effects a correction of the local intensity of the light sources 21, 22 and 78 by multiplying the output signals from the multiplier 92 by the intensity correction factors stored in the list memory 91. The lists for the multipliers 92, 93 are also stored in the list memory 91, which also contains the prediction values for the integration time control. The list for shading correction stored in the list memory 91 is generated when the rotary printing press 5 is started up, just like the characteristic data of the input look-up table in the correction element 87 and is continuously updated during a white value readout by selected unprinted image lines. At the output of the multiplier 93 there are fully corrected image data of the modulation, printing speed, shading and sensor characteristic, which can be routed synchronously via a pipeline bus 94 for further processing and which are fed in parallel to a color value controller 95. The color value controller 95 is one

Programmable gate array circuit (PGA) which, via an AT bus 96, specifies the coordinates of the measurement fields, for example on track 2. The coordinates of the measuring fields for a specific color are generated using a method upstream of the actual color control and are provided on the AT bus 96. Only for these measuring fields is with The color value of a pixel is stored in a memory module 97 with the aid of the color value controller 95. The information about this is transmitted via control lines 98 of the pipeline bus 94. The memory module 97 contains the data on color vectors that can be read via the AT bus 96 for color measurement. The pixels used for color measurement can be addressed in a fine grid. The measuring geometry can be shifted in the fine grid and configured so that a better adaptation to given measuring geometries is realized.

FIG. 8 shows the further processing of the completely corrected image data from all color zones generated on the web 2 or from all modules of the image recording device 15, 16 arranged transversely to the transport direction 10. According to FIG. 8, the corrected actual image data from the entire surface of the web 2 are fed to a data controller 99 implemented in PGA technology via the bidirectional pipeline bus 94. The transmission of the actual image data to the pipeline bus 94 can be carried out in the measurement pauses or in synchronism with the web scanning. The data controller 99 is also connected to a target image memory 100, a differential image memory 101, a parameter image memory 102 and an accumulated differential image memory 103. The data controller 99 is loaded and the operating modes are selected via the AT bus 96. The memories 100 to 103 are connected to an address controller 104 implemented in PGA technology, which is connected to the control lines 98 of the pipeline bus 94. To evaluate the difference image and the accumulated difference image, the difference image memory 101 and the accumulated difference image memory 103 are each available

Look-up table blocks 105, 106 (LUT) in connection. The LUT 105, 106 use data from the target image memory 100 and the parameter image memory 102 to effect one Transformation of the difference image data to colorimetric LAB values of the LAB color space. The outputs of the LUT 105, 106 are connected to an evaluation circuit 107 which is also implemented in PGA technology. A memory module 108 is connected to the evaluation circuit 107, in which the coordinates of a coarse grid for defective image areas are stored during the image measurement. The data of the evaluation circuit 107 can be read via the AT bus 96.

In a teach-in phase, the data controller 99 and the

Evaluation circuit 107 configured so that the

Target image memory 100 and the accumulated

Differential image memory 103 can be combined into a common memory. A desired number m of accumulations can be entered to generate a target image.

As a result, the corrected image data are ulti plexed in the m data controller 99, that after 2 accumulations the nominal image is normalized in the So l L-Bi Idspei 100.

The data controller 99 acts as an adder with an upstream multiplexer.

If target and parameter image data are already available in an external memory, then these can be loaded via the pipeline bus 94 with the aid of a Forth processor (not shown further). The address controller 104 ensures the release of the desired memory area.

After the data have been generated in the memories 100 to 103, the data controller 99 realizes an adder which generates data for a current difference image from the difference between the actual image data and the target image data. Furthermore, the data controller 99 realizes an accumulator, with accumulated difference image data being generated from the sum of the data of an accumulated difference image and a current difference image, via which Pipeline bus 94 can optionally transmit the current differential image, the accumulated differential image or the target image to the Forth processor. The selection is made via a status register in the address controller 104, which is loaded via the AT bus 96. The address controller 104 used for address generation and memory management is synchronized by the signals provided on the control lines 98. The operating modes are selected via a control register. The address controller 104 continuously ensures the refresh of the memories 100-103.

With the aid of the LUT 105, 106, the current difference image and the accumulated difference image are evaluated during the image inspection as a function of the parameter image data in the parameter image memory 102 and the absolute brightness. The evaluation circuit 107 assigns error classes to the differential image data from the data resulting at the outputs of the LUT 105, 106. The error data are stored in the memory module 108 for documentation and statistics. If the amount of the difference image exceeds a predetermined limit value, then the evaluation circuit 107 issues an error message via the AT bus 96. For this purpose, an address generator within the evaluation circuit 107 generates a coarse grid parallel to the address controller 104, which facilitates the location of the fault location. The fault location and type of fault are stored in memory module 108.

The parameter image memory 102 contains the control information about the processing of each individual pixel. With the aid of this control information, the data in the target image memory 100 can be used to reduce a required non-linear characteristic curve for error evaluation. For this purpose, the following parameters are contained in the parameter memory 102: parameters for the edge markings, one Weight function for defining the weighting of image errors in the inspection process, color measurement values for a marked image point, which are stored in a pointer-controlled list, and the shading measurement points and calibration points of the CCD sensors 82. By setting bits for the edge markings, the image format including the page limitation is set. The parameters for the weight function represent a measure of the error assessment. As a result, errors in homogeneous areas of the printed image can be weighted more than errors on contours in the printed image. A gray value-dependent control is used here so that the colorimetric values x *, y *, z * and i * are formed for image inspection via the LUT 105, 106. The parameter expressed by the weight function is used in the address controller 104 for the switching of characteristic curves, and the assignment to various error classes can be made via a table with the aid of the evaluation circuit 107, the errors being able to be evaluated in individual classes in the sense of an error histogram.

A bit ENC for controlling the color measurement is output by the data controller 99 via a separate control line 109. The pixels intended for color measurement are entered in a list in the order in which they are scanned, so that they can be transferred as color measurement values after further processing of the image measurement data by the Forth processor. For the shading measurement, the bit ENC is set in a selected, unprinted measuring line, so that a measurement of the paper white value of the web 2 is carried out at the same time. These measured values are also formatted as list data. Further processing, in particular the accumulation and loading of the shading values, is also carried out by the Forth processor. A special element of a CCD line is provided for calibrating the absolute sensitivity of the CCD sensors 82 and the color temperature of the associated light sources 21, 22 and 78, respectively is also transferred to the list memory by the set bit ENC and is thus available for further evaluation.

Reference list

1 drive element

2 lanes

3, 4 printing unit

5 rotary printing press

6, 7, 8, 9 color distribution device

10 Transport direction

11, 12, 13, 14 rubber cylinders

15, 16 image recording device

17, 18 bearings

19, 20 leadership

21, 22 light source

23, 24 photoelectric receiver

25 encoders

26, 27, 28, 29 register adjusters

30 machine control

31 control panel

32 entry and exit points

33 control circuit

34 Device for processing the

Bi Id signals

35 comparators

36 reference indicators

37 Control device

38 Error detection logic

39 computers

40 Bi Idschi rm

41 keyboard

42 Cursor control device

43 Image measuring device

44 network

45 Dial-up modem

46 Transceiver unit

47 acoustic signal generator , 49, 50, 51 imaging system, 53, 54, 55 filter, 57, 58, 59 CCD sensors adjustment elements optical imaging system, 63, 64, 65 color filter protective glass CCD lines adjustment elements image elements lens array color filter image guide optical imaging system CCD- Sensor adjustment elements cylinder receiver modules light source device for light quantity control <synchronizing device incremental encoder CCD sensor amplifier sample hold element analog-digital converter processing unit correction element accumulation unit row memory timer list memory, 93. Multiplier pipeline bus color value controller AT-Bus 97 memory modules

98 tax lines

99 Data controller

100 target Bi Id memory

101 Difference picture Idspei rather

102 Parameterbi Idspei rather

103 accumulated difference image rather

104 address controller

105, 106 look-up table blocks

107 evaluation circuit

108 memory module

109 Tax line

110 data storage rather

Claims

claims

1. A method for controlling or regulating operations of a printing machine, in which image signals from at least one surface, at least one printed product, are generated with at least one image recording device, and in which the image signals are fed to a processing device in which the signals for the control or Control of the operating processes are generated, characterized in that coordinates of the measuring locations for the image recording device (15, 16) are determined from image information which reproduces at least the surface of the printed product (2).

2. The method of claim 1, d a d u r c h g e k e n n z e i c h n e t that the image information

Image recording device (15, 16) are removed, which detects the entire surface of the printed product (2) within the printing machine (5).

3. The method of claim 2, d a d u r c h g e k e n n z e i c h n e t that the image recording device (15, 16) in addition to the entire surface of the printed product (2)

Surface of the printed product (2) relative to

Bi Ldaufnahmeeinrichtung (15, 16) scans promoting device.

4. The method according to claim 1, characterized in that the image information is taken from an image recording device (43), the one Image of the surface of the printed product (2) is scanned outside the printing machine (5).

5. The method of claim 1, d a d u r c h g e k e n n z e i c h n e t that the image information

Device (39, 40, 41, 42) for image generation can be removed.

6. The method of claim 5, d a d u r c h g e k e n n z e i c h n e t that the image information is generated with a digital computer (39), which is part of the

Device (39, 40, 41, 42) for image generation.

7. The method of claim 1, d a d u r c h g e k e n n z e i c h n e t that the image information is taken from a data memory (110).

8. The method of claim 1, d a d u r c h g e k e n n z e i c h n e t that the Bi Ldi nf ormati onen a

Image receiving device (15, 16) can be removed, which is directed to a printing material (2) following a printing unit (3, 4) of a printing machine (5).

9. The method according to claim 2 to 8, characterized in that from the image information coordinates for measuring locations for actual value acquisition of color measurement values for the control or regulation of a color distribution device (6, 7, 8, 9) of a printing press (5) are determined. 3?

10. The method according to claim 9, d a d u r c h g e k e n n z e i c h n e t that when starting the printing machine (5) actual values

Measuring locations can be obtained in a color measuring strip generated during printing, that for controlling or regulating the

Color distribution device (6, 7, 8, 9) during the

Start-up of the printing machine (5) until a

Okay state predetermined target values are used that the operator of the

Printing machine (5) an OK signal to a control or

Control device (37) there, and that from the okay signal actual values from measuring locations in

Print image can be obtained.

11. The method according to claim 2 to 8, d a d u r c h g e k e n n z e i c h n e t that coordinates for measuring locations for the actual value extraction of moisture measurement values for the control or regulation of a FeuchtπtitteIvertei Lungseinri direction of an offset printing machine (5) are determined from the image information.

12. The method according to claim 2 to 8, d a d u r c h g e k e n n z e i c h n e t that coordinates from the image information for measuring locations for obtaining actual values from register deviations for the control or regulation of a

Register setting device (26, 27, 28, 29) of a printing press (5) can be determined.

13. The method according to claim 1, characterized in that, in addition to determining the coordinates for measuring locations, the surface of the printed product (2) reproducing image information from the operator of the printing machine (5) visible display device (40) are supplied.

14. A device for controlling or regulating operations of a printing machine, characterized in that at least one image recording device (15, 16) is provided _/ on the surface of the

Printed product (2) is directed _/ that said image pickup means _(15/16) with a

Control and regulating circuit (33) is connected _/ that the control and regulating circuit (33) image information can be fed _/ which the surface of the

Play printed product (2) _/ and that the control and regulating circuit (33) with

Actuators _(6/7, _8/9) for influencing the

Operations within the printing

Machine (5) is connected.

15. The device according to claim 14 _/ characterized in that the image recording device (15, 16) contains at least one optoelectronic component (82).

16. The device according to claim 15, characterized in that the image location to be scanned on the surface of the printed product (2) is illuminated with a light source (21, 22, 78), the intensity of which depends on the speed of the printed product (2) and the contrast of the Druckbi Ides is adjustable.

17. The device according to claim 14, characterized in that the image recording device (15, 16) contains at least one thermoelectric component.

18. Device according to claim 14, so that the image recording device (15, -16) contains at least one receiver element for corpuscular radiation.

19. Device according to claim 14, so that the image recording device (15, -16) is coupled to a position device (19, 20) which can be supplied with manually entered or preset positioning signals.

20. Device according to claim 19, so that the image recording device (15, 16) for measurement can be positioned directly on a print image generated on the surface of the printed product (2).

21. Device according to claim 20, so that the image recording device (15, 16) can be positioned for measurement on a print control strip that is also printed outside the print image.

22. Device according to claim 20, so that the image recording device (15, 16) can be positioned for measurement on at least one register cross that is also printed outside the printed image.

23. Device according to claim 19, so that the image recording device (15, 16) is perpendicular to the

Remote control of the printed product surface.

24. Device according to claim 19, so that the image recording device (15, 16) can be pivoted about an axis (17, 18) substantially perpendicular to the transport direction (10).

25. The device according to claim 14, so that the image recording device (15, 16) is directed over the entire width onto the surface of the printed product (2), wherein a plurality of inline arranged image sensors (77) are provided, each scanning a zone.

26. The device according to claim 25, so that the zone width to be scanned is variable.

27. The device according to claim 25, so that the scanning zones correspond to the zones which are specified by a color distribution device (6, 7, 8, 9) of a printing press (5).

28. The device as claimed in claim 14, so that the image recording device (15, 16) can be cyclically initiated at an identical scanning location.

29. The device according to claim 14, characterized in that the image recording device (15, 16) is associated with an arrangement for compensating for highlight defects.

30. The device according to claim 14, d a d u r c h g e k e n n z e i c h n e that an optical image guide (72) is provided for the transmission of the signals reproducing the image.

31. Device according to claim 14, so that a wireless transmission link is provided for the transmission of the signals reproducing the image.

32. Device according to claim 31, d a d u r c h g e k e n n z e i c h n e t that the transmission path contains electromagnetic transmission and reception elements.

33. Device according to claim 31, d a d u r c h g e k e n n z e i c h n e t that the transmission link contains acoustic transmit and receive elements.

34. Device according to claim 31, d a d u r c h g e k e n n z e i c h n e t that the transmission path contains IR transmission and reception elements.

35. Device according to claim 14, so that the control and regulating circuit (33) is assigned locally to the image recording device (15, 16).

36. Device according to claim 14, characterized in that a device (25) for measuring the position of the printed product (2) is provided at a fixed point, which is connected to the control circuit (33).

37. Device according to claim 36, characterized in that an i ncrementa ler rotary encoder (25) is coupled to the speed measurement on a rotating cylinder (11, 12, 13, 14) transporting the printed product (2 ⁾ .

38. Device according to claim 37, characterized in that the rotary encoder (25) is connected to a timer (90) arranged in the control circuit (33), the timer (90) having a circuit for changing the integration time of CCD sensors (82 ), which are assigned to the image recording device (15, 16).

39. Device according to claim 14, characterized in that an output of the control circuit (33) is connected to a screen output device (39) to which a screen (40 ^{) is} connected, on which a desired image, an actual one, either individually or in partial images Image and a difference image can be displayed.

40. Device according to claim 14 _/ characterized in that a reference variable encoder (36) is provided within the control and regulating circuit (33), which can be connected to a memory (110) arranged outside the regulating circuit (33).

41. Device according to claim 40, characterized in that the memory contains target image data from an earlier print job of a printing press (5) for the same Druckbi Id.

42. Device according to claim 40, which also means that the memory contains target image data of individual color separations.

43. Device according to claim 40, so that the reference quantity transmitter (36) can be connected to an offline image measuring device (43).

44. Device according to claim 43, so that a correct template can be used as a template for the image measuring device (43).

45. Device according to claim 43, d a d u r c h g e k e n n z e i c h n e t that partial images of an up-to-date template can be used as a template for the image measuring device (43), layout signals can be fed to the reference variable generator (36) for positioning the partial images in accordance with the up-to-date template.

46. A device according to claim 40, characterized in that an arrangement for evaluating the time intervals and amounts of the control signals (33) given interactively by the operator to the control signals is provided, and that when the threshold values for the time intervals and / or the amounts are undershot are those that are currently present Actual values can be entered as target values.

47. Device according to claim 40, so that the reference quantity generator (36) can be supplied with signals which can be taken from an external setpoint memory.

48. Device according to claim 40, so that signals which can be input by hand can be fed to the reference quantity transmitter (36).

49. Device according to claim 40, so that the setpoint values which can be obtained from the reference variable generator (36) can be changed as a percentage.

50. Device according to claim 14, characterized in that within the control and regulating circuit (33) a comparison device (35) for the actual image signals recorded by the image recording device (15, 16) and the target image signals provided by the reference variable transmitter (36) are provided an error signal can be output if the output signal of the comparison device (35) deviates from a limit value.

51. Device according to claim 50, d a d u r c h g e k e n n z e i c h n e t that the error signal is acoustic.

52. Device according to claim 50, characterized in that the error signal can be generated optically on a screen connected to the control circuit (40), wherein the defective image areas in the actual image can be marked marked on the screen (40).

53. Device according to claim 50, so that the error signal can be fed to a marking device for the faulty print images generated with a printing press (5) on the printed product (2).

54. Device according to claim 53, so that the error signal can be fed to a waste gate arranged downstream of the printing units (3, 4) of the printing press (5).

55. Device according to claim 14, d a d u r c h g e k e n n z e i c h n e t that the control circuit (33) a

Error detection logic (38) is assigned, to which the processed actual image signals and the output signals of a comparison device (35) can be fed, the type of error and the time of occurrence being able to be output alphanumerically on a screen (40) connected to the control circuit (33).

56. Device according to claim 55, d a d u r c h g e k e n n z e i c h n e t that the output of signals to the actuators (6, 7, 8, 9) for influencing the operations depending on the output signal of the error detection logic k is blocked.

57. Device according to claim 14, characterized in that the control and regulating circuit contains Fuzzi logic,

58. Device according to claim 14, characterized in that the control and regulating circuit (33) is connected to a computer (39) to which an alphanumeric keyboard (41), a cursor control device (42) and a screen (40) is connected .

59. Device according to claim 58, d a d u r c h g e k e n n z e i c h n e t that with the cursor control device (42) in the printed image on the screen (40), which was generated by means of a printing press (5) on the printed product (2), the scanning location for the

Image recording device (15, 16) can be selected and marked, the signals to the scanning location being able to be fed to a positioning device for the image recording device (15, 16).

60. Device according to claim 58, which also means that a reference variable encoder (36) can be used to remove it

Target image data can be generated with the help of the computer (39) signals for the color-dependent scanning location, which the

Positioning device for the

Image recording device (15, 16) can be fed.