EP3988309A1 - Flexographic printing machine, method for operating a flexographic printing machine, system and sleeve - Google Patents

Abstract

A method according to the invention for operating a flexographic printing machine, with a printing cylinder (16) carrying a sleeve (3) with at least one flexographic printing form (5) or a flexographic printing cylinder and an impression cylinder (17), the print register of the flexographic printing form or the flexographic printing cylinder being transferred to a further flexographic printing form or Is set to a further flexographic printing cylinder and/or the color density is set and/or a color inspection is carried out using a sensor (402) is characterized in that before printing an image (410) of the surface of the sleeve with the at least one flexographic printing form is captured by a camera (400) and the image is subjected to image processing, with at least one register mark (310) and/or at least one color measuring field (312) being x-y localized; and that before the setting, a sensor (402) for detecting the register mark is automatically moved to the y position of the register mark and the register mark is detected and/or that before the setting, a sensor (402) for detecting the color measurement field is automatically moved to the y -Position of the color patch is moved and the color patch is captured. The invention advantageously makes it possible to print cost-effectively and with high quality in industrial flexographic printing. The method according to the invention advantageously also makes it possible to further automate the printing.

Description

invention

The invention relates to a method having the features of the preamble of claim 1 and a method having the features of the preamble of claim 28.

The invention further relates to a flexographic printing machine, wherein the flexographic printing machine is operated for printing a printing material with flexographic printing ink according to a method according to the invention, having the features of the preamble of claim 22

The invention further relates to a system comprising a flexographic printing machine according to the invention and a measuring device for measuring an image with the features of the preamble of claim 24.

The invention further relates to a sleeve for use in a method according to the invention or for use in a flexographic printing machine according to the invention or for use in a system according to the invention with the features of the preamble of claim 26.

field of technology

The invention lies in the technical field of the graphics industry and there in particular in the field of operating a flexographic printing machine, ie a rotary printing machine for printing with flexographic printing forms. In particular, the invention lies in the sub-area of setting, in particular controlling or regulating, the machine with regard to the color register and/or the color density and/or the color inspection.

State of the art

In so-called flexographic printing, in particular in industrial, web-processing flexographic printing, there is a need to print cost-effectively at high speeds using flexographic printing forms that vary from print job to print job, and to keep the resulting waste low and the print quality high.

Changing print jobs with different print forms or different print motifs can cause problems: the print motifs can have places where a lot is printed and places where little is printed; and places where there is no or only insignificant printing.

Flexographic printing forms can be measured before printing, for example in a measuring station. The one not released yet DE102019206705 discloses a device for measuring elevations on the surface of a body of revolution and creates an improvement which, in particular, makes it possible to measure elevations of bodies of revolution, such as flexographic printing dots of a flexographic printing plate, quickly and with high precision. The device disclosed in the document for measuring elevations on the surface of a rotating body designed as a cylinder, roller, sleeve or plate of a printing press, e.g. a flexographic printing plate mounted on a sleeve, with a first motor for rotating the rotating body about an axis of rotation and with a Measuring device is characterized in that the measuring device for contactless measurement comprises at least one radiation source and at least one area camera.

The other documents cited and described in the aforementioned document DE3302798A1 , DE102014215648A1 , EP3251850 , DE102006060464A1 , WO2010146040A1 , WO2008049510A1 and the " ^smartGPS® " system from Bobst described there form further prior art. Likewise the system "ARun" of the company Allstein. Both systems use pickup rollers.

With the so-called "flying job change" between a job and a follow-up job, which should take place in a few seconds, it can happen that register marks of flexographic printing forms of the job and the follow-up job are in different positions (axially and/or in the circumferential direction). Register sensors must then be repositioned. Manual repositioning is disadvantageous: it takes a long time and is inaccurate/prone to errors.

Scanning rollers do not appear to be suitable for recognizing automated register marks, especially in the case of high-resolution flexographic printing forms with very fine elevations. There is also the risk that such elevations will be damaged by scanning rollers.

Technical task

It is an object of the present invention to provide an improvement over the prior art, which in particular makes it possible to print cost-effectively and with high quality in industrial flexographic printing.

Solution according to the invention

According to the invention, this object is achieved by a method according to claim 1, a method according to claim 28, a flexographic printing machine according to claim 22, a system according to claim 24 and a sleeve according to claim 26.

Advantageous and therefore preferred developments of the invention result from the dependent claims as well as from the description and the drawings.

A method according to the invention for operating a flexographic printing machine, with a printing cylinder carrying a sleeve with at least one flexographic printing forme or a flexographic printing cylinder and an impression cylinder, wherein the print register of the flexographic printing forme or the flexographic printing cylinder is adjusted to a further flexographic printing forme or to a further flexographic printing cylinder and/or the color density adjusted and/or a color inspection is carried out using a sensor, is characterized in that before printing, an image of the surface of the sleeve with the at least one flexographic printing form is captured by a camera and the image is subjected to image processing, with at least one register mark and/or at least one color measuring field being xy-localized; and that before the setting, a sensor for detecting the register mark is automatically moved to the y-position of the register mark and the register mark is detected and/or that before the setting, a sensor for detecting the color measuring field is automatically moved to the y-position of the color measuring field and the color measurement field is captured and that before printing at least one image of the surface of a plurality of sleeves with a plurality of flexographic printing forms is captured by at least one camera to configure a register controller of the flexographic printing machine and that the image is subjected to digital image processing, with at least two register marks being xy-localized and that using the xy-located registration mark position data automates the configuration of the register controller for detecting registration marks.

An (alternatively formulated) method according to the invention for operating a flexographic printing machine, with at least two printing cylinders - each carrying a sleeve with at least one flexographic printing forme each - wherein the pressure register of the flexographic printing forms is adjusted to one another and a sensor for detecting register marks is used is characterized in that before printing, a respective image of the surfaces of the sleeves is captured by a camera and the respective image is subjected to digital image processing, with a total of at least two register marks being x-y-localized, and that before setting the sensor is automatically connected to the y position of the register marks is moved and the register marks are detected and that, using the x-y located register mark position data, the configuration of the register controller for register mark detection is automated.

A flexographic printing machine according to the invention, with at least one flexographic printing unit - comprising a printing cylinder carrying a sleeve with at least one flexographic printing forme or a flexographic printing cylinder, an impression cylinder and an anilox roller - the flexographic printing machine for printing a printing material with Flexographic printing ink is operated according to one of the preceding methods, characterized in that the flexographic printing machine comprises at least one servomotor for setting the y-position of the sensor.

A system according to the invention, comprising a flexographic printing machine according to the invention and a measuring device for capturing an image of a sleeve, is characterized in that the measuring device captures the image of the sleeve using camera technology.

A flexographic printing forme or sleeve for a flexographic printing forme according to the invention, the flexographic printing forme or the sleeve being marked with a machine-readable ID, for use in a method according to the invention or for use in a flexographic printing machine according to the invention or for use in a system according to the invention, is characterized in that the machine-readable ID is read by machine and stored on a computer for retrieval.

Advantageous Forms and Effects of the Invention

The invention advantageously makes it possible to print cost-effectively and with high quality in industrial flexographic printing. The method according to the invention advantageously also makes it possible to further automate the printing.

The invention is described and shown for a flexographic printing machine or for flexographic printing forms (letterpress). Alternatively, the invention can be used for engraved printing forms or engraved sleeves (intaglio printing). Therefore, instead of the term "flexo" alternatively "deep" or "flexo or deep" can be used in this application. Instead of “sleeve with flexographic printing form” “sleeve with engraved form” or “engraved sleeve” or “laser engraved sleeve” or “endless sleeve engraved with laser” or “endless printing form” or “endless printing sleeve” can be used.

Developments of the invention

Preferred developments of the invention (in short: developments) are described below.

• dass das Bild berührungslos gemessen wird.
• dass die x-Richtung die Umfangsrichtung der Hülse und die y-Richtung die dazu senkrechte Richtung der Hülse, d.h. die axiale Richtung der Hülse, ist.
• bei der x-y-Lokalisierung eine x-Koordinate und eine y-Koordinate zugewiesen werden.
• dass die x-Richtung als kartesische Koordinate entlang des Umfangs oder als Winkelkoordinate gegeben ist.
• dass der Hülse ein Koordinatenursprung zugeordnet wird.
• dass das Bild die gesamte Umfangslänge und Arbeitsbreite der Hülse umfasst.
• dass die Registermarke bei sich drehendem Druckzylinder an der x-Position erfasst wird.
• dass das Farbmessfeld bei sich drehendem Druckzylinder an der x-Position erfasst wird.
• dass die Bildverarbeitung einen Schritt der rechentechnischen Mustererkennung umfasst.
• dass bei der rechentechnischen Mustererkennung ein vorgegebenes Muster einer Registermarke gesucht wird.
• dass das vorgegebene Muster ein Doppelkeil oder ein Kreis mit einem vorgegebenen Durchmesser ist.
• dass bei der rechentechnischen Mustererkennung ein vorgegebenes Muster eines Farbmessfeldes gesucht wird.
• dass das vorgegebene Muster ein Rechteck mit vorgegebenen Maßen für Länge und Breite ist.
• dass zu der Registermarke oder zu dem Farbmessfeld benachbarte Freiflächen erfasst und bei der rechentechnischen Mustererkennung mitberücksichtigt werden.
• dass die Registermarke und/oder das Farbmessfeld Teil eines Kontrollstreifens ist bzw. sind.
• dass bei der Bildverarbeitung der Kontrollstreifen x-y-lokalisiert wird.
• dass die Flexodruckmaschine ein Flexodruckwerk und wenigstens ein weiteres Flexodruckwerk umfasst, wobei das Flexodruckwerk den Druckzylinder und den Gegendruckzylinder umfasst und das weitere Flexodruckwerk einen weiteren Druckzylinder und einen weiteren Gegendruckzylinder umfasst, wobei der weitere Druckzylinder eine weitere Hülse mit wenigstens einer weiteren Flexodruckform trägt.
• dass das Druckwerk den Sensor für das Erfassen der Registermarke umfasst und dass das weitere Druckwerk einen weiteren Sensor für das Erfassen der Registermarke umfasst.
• dass das Druckwerk den Sensor für das Erfassen des Farbmessfeldes umfasst und dass das weitere Druckwerk einen weiteren Sensor für das Erfassen des Farbmessfeldes umfasst.
• dass der jeweilige Sensor für das Erfassen der Registermarke als eine Kamera ausgebildet ist.
• dass der jeweilige Sensor für das Erfassen des Farbmessfeldes als ein Densitometer ausgebildet ist.
• dass als die Registermarke eine Kante im Druckbild der Flexodruckform erfasst wird.
• dass der Druckzylinder und der weitere Druckzylinder an ihrer jeweiligen Außenoberfläche einen jeweiligen Zapfen an einer jeweiligen Zapfenposition in x-Richtung umfassen.
• dass die Hülse und die weitere Hülse an ihrer jeweiligen Innenoberfläche eine jeweilige Nut in y-Richtung für den jeweiligen Zapfen umfassen.
• dass die Hülse und die weitere Hülse jeweils gegen einen Anschlag des Druckzylinders bzw. des weiteren Druckzylinders in y-Richtung bewegt werden.
• dass die Anschläge in y-Richtung positioniert sind.
• dass die Hülse und die weitere Hülse jeweils mit einer maschinenlesbaren ID markiert sind.
• dass die ID als eindeutiger Identifikator für die Hülse ausgebildet ist.
• dass der Identifikator mehrere Zeichen, insbesondere Ziffern und/oder Buchstaben oder Sonderzeichen, umfasst.
• dass die ID als ein eindimensionaler Code markiert ist, insbesondere ein Barcode, oder als ein zweidimensionaler Code markiert ist, insbesondere ein QR-Code, oder als ein RFID-Chip oder NFC-Chip markiert ist.
• dass die x-Koordinaten und die y-Koordinaten beider Hülsen oder daraus abgeleitete Daten zusammen mit der jeweiligen ID der Hülsen direkt an die Flexodruckmaschine übermittelt.
• dass die x-Koordinaten und die y-Koordinaten beider Hülsen oder daraus abgeleitete Daten zusammen mit der jeweiligen ID der Hülsen indirekt an die Flexodruckmaschine übermittelt, indem die x-Koordinaten und die y-Koordinaten beider Hülsen oder daraus abgeleitete Daten zusammen mit der jeweiligen ID der Hülsen zwischengespeichert und von der Flexodruckmaschine für das Drucken mit den Hülsen abgerufen werden.
• dass das Zwischenspeichern auf einem zentralen Speicher oder einem Cloud-Speicher erfolgt.
• dass das Einstellen nach einem Wechsel des Druckauftrages erfolgt.
• dass das Einstellen des Druckregister ein Steuern oder Regeln des Druckregisters umfasst.
• dass das Regeln des Registers mehrerer in Bahntransportrichtung aufeinander folgender Druckzylinder der Flexodruckmaschine - umfassenden den Druckzylinder, den weiteren Druckzylinder und weitere Druckzylinder mit weitern Hülsen und weiteren Flexodruckformen - relativ zu dem ersten druckenden Druckzylinder der Druckzylinder in Bahntransportrichtung erfolgt.
• dass das Einstellen der Farbdichte ein Steuern oder Regeln der Farbdichte umfasst.
• dass die Registermarke, das Farbmessfeld oder eine weitere Marke als eine Fehlermarke zur Detektion eines Montagefehlers einer Flexodruckform oder mehrerer Flexodruckformen auf der Hülse oder auf mehreren Hülsen ausgebildet ist.
• dass die Fehlermarken wenigstens zweier Flexodruckformen zum Drucken verschiedener Druckfarben übereinander gedruckt und sensorisch erfasst werden.
• dass eine weitere Marke als eine Fehlermarke zur Detektion eines x-y-Positionierungsfehler einer Hülse auf einem Flexodruckzylinder ausgebildet ist.
• dass eine x-y-Position der Fehlermarke sensorisch erfasst und mit der x-y-Position der Registermarke rechentechnisch verglichen und daraus ein x-y-Positionierungsfehler rechentechnisch ermittelt wird.
• dass die Fehlermarke auf die Hülse aufgeklebt wird bzw. ist.
• dass die Hülse und die weitere Hülse jeweils zwei Hülsen umfassen, d.h. jeweils eine innere Adaptionshülse und jeweils eine äußere Druckhülse, wobei die Dicke der Druckhülse geringer als die Dicke der Adaptionshülse ist.
• dass das Bild der Oberfläche der Hülse mit der wenigstens einen Flexodruckform von der Kamera vor dem Drucken erfasst wird.
• dass das Bild der Oberfläche der Hülse mit der wenigstens einen Flexodruckform von der Kamera vor dem Drucken in einer Messeinrichtung gemessen wird.
• dass die Messeinrichtung einen Aufnahmezylinder für die Hülse mit der Flexodruckform umfasst.
• dass der Aufnahmezylinder während des Messens um eine - eine axiale Richtung aufweisenden - Rotationsachse rotiert.
• dass die Messeinrichtung außerhalb der Flexodruckmaschine betrieben wird.
• dass beim Erfassen des Bildes eine Kamera zum Einsatz kommt.
• dass beim Erfassen des Bildes eine Flächenkamera zum Einsatz kommt.
• dass beim Erfassen des Bildes eine Zeilenkamera zum Einsatz kommt.
• dass beim Erfassen des Bildes wenigstens ein CIS-Sensor zum Einsatz kommt.
• dass beim Erfassen des Bildes eine ortsfeste Kamera zum Einsatz kommt.
• dass die Kamera vor dem Messen senkrecht zur axialen Richtung bewegt wird.
• dass die Kamera während des Messens in axialer Richtung bewegt wird.
• dass bim Messen mit der Kamera eine Strahlungsquelle, insbesondere eine Lichtquelle zum Einsatz kommt.
• dass beim Erfassen des Bildes das gesamte Druckbild einer Flexodruckform erfasst wird.
• dass beim Erfassen des Bildes wenigstens eine oder wenigstens zwei Flexodruckformen auf einer Hülse montiert und erfasst wird/werden.
• dass beim Erfassen des Bildes Licht von einer Lichtquelle bis zu Erhebungen der Flexodruckform und von dort zur Kamera gelangt.
• dass beim Erfassen des Bildes wenigstens ein Spiegel zum Einsatz kommt.
• dass der Spiegel beweglich angeordnet ist.
• dass der Spiegel vor dem Messen senkrecht zur axialen Richtung bewegt wird.
• dass der Spiegel während des Messens in axialer Richtung bewegt wird.
• dass beim Erfassen des Bildes Licht von einer Lichtquelle bis zu Erhebungen der Flexodruckform und von dort über den Spiegel zurück zur Kamera gelangt.
• zur Konfiguration des Registerreglers für den Fall, dass auf einer Hülse mehrere Registermarken x-y-lokalisiert werden, aus den erfassten Daten rechentechnisch eine dieser Registermarken ausgewählt wird. Dabei kann vorteilhaft vorgesehen sein, dass eine solche Registermarke ausgewählt wird, deren y-Position im Wesentlichen den y-Positionen von einer oder mehreren Registermarken auf anderen Hülsen entspricht. So kann verhindert werden, dass bei der Konfiguration des Registerreglers eine Registermarke verwendet wird, welche hierzu nicht vorgesehen ist, z.B. eine Registermarke für das Stanzregister statt des Druckregisters.
• dass zur Konfiguration des Registerreglers der Flexodruckmaschine aus den erfassten Daten rechentechnisch abgeleitet und verwendet wird, welche Registermarke der Registermarken-Konfiguration in welchem Druckwerk gedruckt wird.
• dass die Konfiguration des Registerreglers in Abhängigkeit einer vom Druckauftrag abhängigen Reihenfolge der Druckfarben in der Druckmaschine erfolgt, wobei bevorzugt nur die für den Druckauftrag duckenden Druckwerke bzw. Farben berücksichtigt werden.

A respective development of the method according to the invention can be characterized by:

• that the image is measured without contact.
• that the x-direction is the circumferential direction of the sleeve and the y-direction is the direction of the sleeve perpendicular thereto, ie the axial direction of the sleeve.
• an x-coordinate and a y-coordinate are assigned in the xy localization.
• that the x-direction is given as a Cartesian coordinate along the circumference or as an angular coordinate.
• that the sleeve is assigned a coordinate origin.
• that the picture covers the entire circumference and working width of the sleeve.
• that the register mark is detected at the x-position while the printing cylinder is rotating.
• that the color measuring field is recorded at the x-position while the printing cylinder is rotating.
• that the image processing includes a step of computational pattern recognition.
• that a predetermined pattern of a register mark is searched for in the computational pattern recognition.
• that the given pattern is a double wedge or a circle with a given diameter.
• that a predetermined pattern of a color measuring field is searched for in the computational pattern recognition.
• that the given pattern is a rectangle with given dimensions for length and width.
• that free spaces adjacent to the register mark or to the color measuring field are recorded and taken into account in the computational pattern recognition.
• that the register mark and/or the color measurement patch is or are part of a control strip.
• that the control strip is xy-localized during image processing.
• that the flexographic printing machine comprises a flexographic printing unit and at least one additional flexographic printing unit, the flexographic printing unit including the impression cylinder and the impression cylinder and the additional flexographic printing unit including an additional impression cylinder and an additional impression cylinder, the additional impression cylinder carrying an additional sleeve with at least one additional flexographic printing forme.
• that the printing unit includes the sensor for detecting the register mark and that the further printing unit includes a further sensor for detecting the register mark.
• that the printing unit includes the sensor for detecting the color measurement field and that the additional printing unit includes an additional sensor for detecting the color measurement field.
• that the respective sensor for detecting the register mark is designed as a camera.
• that the respective sensor for detecting the color measurement field is designed as a densitometer.
• that an edge in the print image of the flexographic printing form is detected as the register mark.
• that the pressure cylinder and the further pressure cylinder on their respective outer surface comprise a respective pin at a respective pin position in the x-direction.
• that the sleeve and the further sleeve comprise on their respective inner surface a respective groove in the y-direction for the respective pin.
• that the sleeve and the further sleeve are each moved against a stop of the printing cylinder or the further printing cylinder in the y-direction.
• that the stops are positioned in the y-direction.
• that the sleeve and the further sleeve are each marked with a machine-readable ID.
• that the ID is designed as a unique identifier for the sleeve.
• that the identifier comprises several characters, in particular numbers and/or letters or special characters.
• that the ID is marked as a one-dimensional code, in particular a barcode, or is marked as a two-dimensional code, in particular a QR code, or is marked as an RFID chip or NFC chip.
• that the x-coordinates and the y-coordinates of both sleeves or data derived from them are transmitted directly to the flexographic printing machine together with the respective ID of the sleeves.
• that the x-coordinates and the y-coordinates of both sleeves or data derived therefrom together with the respective ID of the sleeves are indirectly transmitted to the flexographic printing machine by the x-coordinates and the y-coordinates of both sleeves or data derived therefrom together with the respective ID of the sleeves are cached and retrieved by the flexographic press for printing with the sleeves.
• that the caching takes place on a central storage or a cloud storage.
• that the setting is made after changing the print job.
• that adjusting the pressure register includes controlling or regulating the pressure register.
• that the register of several printing cylinders of the flexographic printing machine following one another in the direction of web transport - comprising the printing cylinder, the further printing cylinder and further printing cylinders with further sleeves and further flexographic printing forms - is carried out relative to the first printing printing cylinder of the printing cylinders in the direction of web transport.
• that adjusting the color density includes controlling or regulating the color density.
• that the register mark, the color measuring field or another mark is designed as an error mark for detecting an assembly error of a flexographic printing form or several flexographic printing forms on the sleeve or on several sleeves.
• that the error marks of at least two flexographic printing forms for printing different inks are printed one above the other and detected by sensors.
• that another mark is designed as an error mark for detecting an xy positioning error of a sleeve on a flexographic printing cylinder.
• that an xy-position of the error mark is detected by sensors and compared with the xy-position of the register mark by computation and an xy-positioning error is determined therefrom by computation.
• that the error mark is or is glued to the case.
• that the sleeve and the further sleeve each comprise two sleeves, ie one inner adaptation sleeve and one outer pressure sleeve, the thickness of the pressure sleeve being less than the thickness of the adaptation sleeve.
• that the image of the surface of the sleeve with the at least one flexographic printing form is captured by the camera before printing.
• that the image of the surface of the sleeve with the at least one flexographic printing form is measured by the camera in a measuring device before printing.
• that the measuring device comprises a receiving cylinder for the sleeve with the flexographic printing form.
• that the receiving cylinder during the measurement about a - rotating axis of rotation - having an axial direction.
• that the measuring device is operated outside of the flexographic printing machine.
• that a camera is used to capture the image.
• that an area scan camera is used to capture the image.
• that a line scan camera is used to capture the image.
• that at least one CIS sensor is used when capturing the image.
• that a stationary camera is used to capture the image.
• that the camera is moved perpendicular to the axial direction before measuring.
• that the camera is moved in the axial direction during the measurement.
• that when measuring with the camera, a radiation source, in particular a light source, is used.
• that when capturing the image, the entire print image of a flexographic printing form is captured.
• that when capturing the image, at least one or at least two flexographic printing forms are mounted on a sleeve and captured.
• that when capturing the image, light from a light source reaches bumps in the flexographic printing form and from there to the camera.
• that at least one mirror is used when capturing the image.
• that the mirror is movably arranged.
• that the mirror is moved perpendicular to the axial direction before measuring.
• that the mirror is moved in the axial direction during the measurement.
• that when capturing the image, light from a light source travels to bumps on the flexographic printing form and from there back to the camera via the mirror.
• for the configuration of the register controller in the event that several register marks are xy-located on a tube, one of these register marks is selected from the recorded data by means of computation. In this case, it can advantageously be provided that such a register mark is selected whose y-position essentially corresponds to the y-positions of one or more register marks on other sleeves. This prevents the configuration of the register controller from using a register mark that is not intended for this purpose, eg a register mark for the punch register instead of the print register.
• that to configure the register controller of the flexographic printing machine, it is derived from the recorded data and used which register mark of the register mark configuration is printed in which printing unit.
• that the configuration of the register controller takes place as a function of a sequence of the printing colors in the printing press which is dependent on the print job, with preference being given to only the printing units or colors which are to be printed for the print job.

• dass beim Betrieb der Flexodruckmaschine Karton bedruckt wird.
• dass beim Betrieb der Flexodruckmaschine Papier, Folien, Pappe, Folie oder Verbundmaterialien bedruckt werden.
• dass die Hülse wenigstens zwei Flexodruckformen mit gleichen oder unterschiedlichen Druckmotiven trägt.
• dass die zwei Flexodruckformen auf der Hülse in Umfangsrichtung aufeinanderfolgend oder in axialer Richtung aufeinanderfolgend montiert sind.

A respective further development of the flexographic printing machine according to the invention can be distinguished by:

• that cardboard is printed during operation of the flexographic printing machine.
• that paper, foil, cardboard, foil or composite materials are printed during operation of the flexographic printing machine.
• that the sleeve carries at least two flexographic printing forms with the same or different print motifs.
• that the two flexographic printing forms are mounted on the sleeve consecutively in the circumferential direction or consecutively in the axial direction.

• dass die Messeinrichtung Teil einer Messstation ist, welche separat zur Flexodruckmaschine angeordnet ist.
• dass die Hülse mit einer maschinenlesbaren ID markiert ist.
• dass die ID als eindeutiger Identifikator für die Hülse ausgebildet ist.
• dass der Identifikator mehrere Zeichen, insbesondere Ziffern und/oder Buchstaben und/oder Sonderzeichen, umfasst.
• dass die ID als ein eindimensionaler Code markiert ist, insbesondere ein Barcode, oder als ein zweidimensionaler Code markiert ist, insbesondere ein QR-Code, oder als ein RFID-Chip oder NFC-Chip markiert ist.
• das System eine Mehrzahl von Rasterwalzen verschiedener Raster und/oder Rasterfeinheiten umfasst und dass die Flexodruckmaschine beim Drucken mit einer Flexodruckform mit einer Rasterwalze betrieben wird, welche aus der Mehrzahl von Rasterwalzen rechentechnisch unter Verwendung der Punktdichte der Flexodruckform oder daraus abgeleiteter Daten ausgewählt wird.
• dass die ausgewählte Rasterwalze ein Raster aufweist, welches feiner als das Raster der Flexodruckform ist.

A respective further development of the system according to the invention can be distinguished by:

• that the measuring device is part of a measuring station which is arranged separately from the flexographic printing machine.
• that the case is marked with a machine-readable ID.
• that the ID is designed as a unique identifier for the sleeve.
• that the identifier comprises several characters, in particular numbers and/or letters and/or special characters.
• that the ID is marked as a one-dimensional code, in particular a barcode, or is marked as a two-dimensional code, in particular a QR code, or is marked as an RFID chip or NFC chip.
• the system comprises a plurality of anilox rollers of different screens and/or screen rulings and that the flexographic printing machine is operated with a screen roller when printing with a flexographic printing forme, which is selected from the plurality of anilox rollers by computer using the point density of the flexographic printing forme or data derived therefrom.
• that the selected screen roller has a screen which is finer than the screen of the flexographic printing form.

• dass die Markierung mit der maschinenlesbaren ID unter Einsatz eines Markierungsmittels erfolgt, welches insbesondere von einem RFID-Chip verschieden ist.

A respective further development of the flexographic printing forme or sleeve for a flexographic printing forme according to the invention can be characterized in that:

• that the marking with the machine-readable ID takes place using a marking means which is different from an RFID chip in particular.

The features and combinations of features disclosed in the above sections Technical field, invention and developments as well as in the following section Working examples represent further advantageous developments of the invention - in any combination with one another.

Embodiments of the invention and figures

the Figures 1 to 5 show a flexographic printing machine, a measuring station with a measuring device (various embodiments) and a measuring method.

the figure 6 shows the captured image of a sleeve with two flexographic printing forms as an example.

Features corresponding to one another are provided with the same reference symbols in the figures. Reference symbols that are repeated in the figures have been partially omitted for the sake of clarity.

figure 1 shows a cross section of a rotatable support cylinder 1 of a measuring station 2, a sleeve 3 (sleeve) held on the support cylinder and a sleeve held on the sleeve, preferably attached to the sleeve by means of an adhesive tape 4 (or alternatively by means of an adhesive coating of the sleeve) (so-called "Mount"), at least with regard to its topography to be measured printing plate 5 (flexographic printing form) as a body of revolution 6.

A motor 7 can be present in the measuring station for rotating the carrier cylinder during the measurement. The measuring station can be part of a so-called "mounter" (in which pressure plates are mounted on carrier sleeves) or can be provided separately from a "mounter". The measuring station can be provided separately from a printing press 8 (flexographic printing press)—with at least one printing unit 9 (flexographic printing unit) for the printing plate 5 and a dryer 10 for printing and drying a preferably web-shaped printing material 11. The printing plate is preferably a flexographic printing form with a diameter of 106 mm to 340 mm. The dryer is preferably a hot air dryer and/or a UV dryer and/or an electron beam dryer and/or an IR dryer. The sleeve can be pushed laterally onto the carrier cylinder. The carrier cylinder can have openings in its outer surface, from which - to widen the sleeve and to generate an air cushion when pushed on - compressed air can be ejected. After the measurement, the sleeve with the printing plate can be removed from the measuring device and pushed onto a printing cylinder of the printing unit in the printing press. A hydraulic clamping system can also be used as an alternative to the pneumatic clamping system.

figure 1 12 also shows a digital computer and/or digital memory 39, 39b, 123, 317, 401 and/or 403. The measuring device can generate data and transmit it to the computer/memory. The data can be measured values or data derived from them, which are generated when the sleeve 3 and/or the flexographic printing form(s) 5 are measured. The computer/memory can be part of the measuring device 2 or part of the flexographic printing machine 8; or can be provided separately, e.g. as a central computer/memory (e.g. a print shop) or cloud-based. The computer/memory can transmit data to the flexographic printing machine, for example the measured values or the data derived therefrom or data further derived therefrom. The further derived data can be generated by a computer-implemented algorithm and/or an AI (Artificial Intelligence; software- and/or hardware-based, self- and machine-learning system). The computer/memory can receive data from several measuring stations and transmit data to several flexographic printing machines. The system consisting of flexographic printing machine(s), measuring station(s) and computer/memory allows for a high level of automation during printing, right through to autonomous printing; Error-prone inputs and/or changes to data on the part of the operator can be avoided in this advantageous way.

The measuring station 2 can be calibrated with the aid of measuring rings 12 on the carrier cylinder 1 . Alternatively, a measuring sleeve or the carrier cylinder itself can be used for calibration.

The following figures show preferred embodiments of devices for the non-contact measurement of elevations 13 on the surface 14 of a rotary body 6 designed as a flexographic printing form of the printing press 8 (cf. Figure 2C ). The elevations can be flexographic printing dots (in the grid) or flexographic printing areas (in the full area) of a flexographic printing plate. In the following exemplary embodiments, the measurement of a printing plate 5 is described as an example. By measuring the printing plate, an automatic presetting of the respective optimum working pressure between the cylinders involved in the printing process, eg screen cylinder 15, impression cylinder 16 with printing plate 5 and impression cylinder 17, is made possible.

the Figures 2A to 2C show a preferred embodiment of the device for measuring the topography of a printing plate 5; Figure 2A in cross section, Figure 2B in top view and Figure 2C an enlarged section Figure 2A . According to this embodiment, the topography is preferably recorded with a plurality of devices 18 as part of a 3D radius determination with an optional reference line.

In this and the following embodiments, "2D" means that a section of the printing plate 5 (e.g. annular height profile) is scanned and "3D" means that the entire printing plate 5 (e.g. cylindrical height profile composed of annular height profiles) is scanned.

The device comprises a plurality of radiation sources 19, in particular light sources 19, preferably LED light sources, at least one reflector 20, e.g. a mirror, and at least one light receiver 21, preferably an area camera and particularly preferably a high-speed camera. In the following, light sources are assumed to be the radiation sources, i.e. visible light is emitted. Alternatively, the radiation source can emit other electromagnetic radiation, e.g., infrared. The light sources are preferably arranged in a row perpendicular to the axis of rotation 22 of the carrier cylinder 1 and produce a light curtain 23, with the carrier cylinder 1 with sleeve 3 and printing plate 5, i.e. the contour, generating a shadow 24. The reflected and then received light 25, ie essentially the emitted light 23 without the light 24 shaded by the topography 13, carries information about the topography 13 to be measured. The reflector 20 can be designed as a reflective foil.

The light source 19 is planar (area camera). The light source preferably emits visible light. The light sources 19 and light receivers 21 preferably cover the working width 26, ie the extension of the printing plate 5 in the direction of its axis 22 (eg 1650 mm). Preferably n light sources 19 and light receivers 21 can be provided, for example 2>n>69. A higher cap than 69 may be required when using smaller sized cameras. If the entire working width 26 is covered, the printing plate 5 can be measured during one revolution of the carrier cylinder 1.

Otherwise, the light sources and light receivers must be moved or clocked in the axial direction 27 along the printing plate.

Inexpensive but fast-working cameras 21 are preferably used, e.g. black-and-white cameras. The cameras can record 5 individual images or a film as the printing plate rotates.

The device consisting of light sources 19, reflector 20 and light receiver 21 can preferably be moved in a direction 28 perpendicular to the axis 22 of the carrier cylinder 1 in order to direct the light strip 23 generated onto the topography 13 to be measured. A motor 29 can be present for this purpose. Provision can also be made for the reflector to be stationary and for only the light source and/or the light receiver to be moved, e.g. by a motor.

Contrary to what is shown, the topography 13 is preferably measured in a vertical direction (e.g. camera "below" and reflector "above") and not in a horizontal direction, since in this case a possible deflection of the carrier cylinder 1 and the reference object 30 can be ignored. In this preferred solution, you have to look at the Figure 2a rotated 90° clockwise.

A line-like object 30, preferably a taut thread 30 or a taut string 30, e.g. a metal wire or a carbon fiber or a knife (or a knife-like object or an object with a cutting edge) or a beam, is provided as an optional reference object 30, which a reference line 31 for the plurality of light receivers 21 is generated. The line-like object preferably extends parallel to the axis of the carrier cylinder 1 and is arranged at a small distance 32, for example 2 mm to 10 mm (maximum up to 20 mm), from its lateral surface 33 or the printing plate 5 arranged thereon. The received light 25 also contains information about the reference object 30 that can be evaluated, e.g. its location and/or distance from the (preferably etched and therefore lower than the elevations 13) surface 14 of the printing plate 5. The reference line can be used to calculate the radial distance R of the topography 13 or the contour or the contour elevations of the reference object 30, preferably using digital image processing will. The distance of the reference object 30 from the axis 22 of the carrier cylinder 1 is known from the arrangement and/or motorized adjustment of the reference object 30 (optionally together with light source 19 and light receiver 21 and possibly reflector 20). The radial spacing of the contour elevations, ie the radius R of the pressure points, can thus be determined by computation. Due to the use of the reference object 30 and thus the presence of shadowing caused by it or a reference line 31 corresponding to the shadowing (in the recorded image or from the received light) of each camera 21, an exact, e.g. pixel-precise, alignment of the cameras to one another is not mandatory necessary. Furthermore, the reference object 30 can be used to calibrate the measuring system.

The reference object 30 can be coupled to the light source 19 and/or the motor 29 for movement or adjustment in the direction 28 . Alternatively, the reference object can have its own motor 29b for moving/adjusting.

For the initial referencing of the device, a measurement is preferably carried out with the ("empty") carrier cylinder or a measuring sleeve arranged thereon (measurement of the distance between the reference object and the surface from AS to BS).

To further initialize the device before the measurement process, the area camera 21 is preferably first moved in the direction 28 toward the carrier cylinder 1 . The movement is preferably stopped as soon as the camera detects the first elevation. Thereafter, the reference object 30 is preferably also moved in direction 28 up to a predetermined distance, e.g. 2 mm, from the carrier cylinder 1.

Alternatively, light source 19 and light receiver 21 can also be arranged on opposite sides of support cylinder 1; in this case the reflector 20 can be dispensed with.

The light source 19, the reflector 20 (if present according to the embodiment), the light receiver 21 and the optional reference object 30 preferably form a (vertical to the axis 22 of the support cylinder) movable. in particular a motorized adjustable or movable unit 34.

During the measurement, the carrier cylinder 1 rotates with the printing plate 5 located thereon, so that preferably all elevations 13 in the circumferential direction 35 can be detected. Depending on the angular position of the carrier cylinder 1, a topographical image and the radius R of individual elevations 13, e.g. flexographic printing dots, relative to the axis 22 or the diameter D (measured between opposite elevations) can be determined from this.

In the enlarged view of the Figure 2C a section of the topography 13 of the printing plate 5 is shown and the shading 24 of the topography and the shading 36 of the reference object 30 can be seen. The topography elevations 13 can be in the range from 2 μm to 20 mm.

A sensor 37 can also be provided, which detects the sleeve 3 and/or the pressure plate 5 using an identification feature 38 (cf. Figure 2B ) detected. This feature can be a barcode, a 2D code (eg QR code or data matrix code), an RFID chip or an NFC chip, for example.

The signals and/or data generated by the light receivers 21, which include information about the topography 13 of the measured surface 14 and about the reference object 30, are transmitted to a computer 39, preferably via a cable or radio link, and processed there. The computer is connected to the printing machine 8 . The computer 39 evaluates the information.

Before the measurement, the reference object 30 can be brought into the detection range of the light receiver 21 in order to calibrate the light receiver. The light receiver 21 detects and transmits the calibration signals generated to the computer 39 . The calibration data are recorded in the digital memory 40 of the computer 39 .

This makes it possible to store a virtual reference object in the computer 39 .

The reference object 30 is then removed from the detection range of the light receiver 21 and the topography 39 of the surface 14 to be measured is further processed together with the virtual reference object.

The result of the evaluation is stored in a digital memory 40 of the computer, in a memory 40 of the printing press or in a cloud-based memory. The results are preferably stored in association with the respective identification feature 38 . When the printing plate 5 mounted on a sleeve (or the sleeve/flexographic printing form) is later used in the printing press 8, the identification feature 38 of the printing plate 5 or of the flexographic printing form (or the sleeve) can be read in again. The values stored for the identification feature 38 can then be called up, e.g. for the purpose of presetting. For example, it can be provided that the printing machine receives the data required for a print job from the cloud-based storage.

The result of the evaluation can preferably include up to four values: The operationally required pressure infeeds of the printing cylinder 16, i.e. the cylinder carrying the measured printing plate 5 on the two sides 41 or AS (drive side) and 42 or BS (operating side) against the impression cylinder 17 or printing material transport cylinder 17 and the operationally required print infeeds of an anilox roller 15 inking the measured printing plate 5 on the two sides 41 or AS (drive side) and 42 or BS (operating side) against the printing cylinder 16.

Furthermore, a device 43 for detecting the point density, for example via optical scanning, can be provided, preferably a CIS scanner bar (contact image sensor), a line camera, or a laser triangulation device. Alternatively, the device 43 can be a pivotable or movable mirror such that it can be used together with the light sources 19, 21 for measuring the point density. The device is preferably connected to a device for image processing and/or image evaluation, which the computer 39 - or the computer 39 with corresponding programming - is or which can be another computer 39b.

A CIS scanner bar can be arranged axially parallel to the cylinder. It preferably includes LEDs for lighting and sensors for image recording (similar to a scanner bar in a commercial copier). The bar is preferably arranged at a distance of 1 to 2 cm from the surface or is positioned at this distance. The cylinder with the surface to be measured, e.g. the printing plate, rotates under the bar, which creates an image of the surface and provides an image evaluation for a point density evaluation. The data obtained from recording the dot density can also be used, for example, to select or recommend an anilox roller from a set of available anilox rollers that is optimal for printing with the recorded printing form.

the Figures 3A and 3B show a preferred embodiment of the device for measuring the topography of a printing plate 5; Figure 3A in cross section and Figure 3B in top view. According to this embodiment, the topography is preferably recorded with a laser micrometer 44 as part of a 2D diameter determination.

The device comprises a light source 19, preferably a linear LED light source 19 or a linear laser 19, and a light receiver 21, preferably a line camera 21. The laser and light receiver together form a laser micrometer 44. The light source 19 produces a light curtain 23 and the carrier cylinder 1 with sleeve 3 and pressure plate 5 creates a shading 24. The line lengths of the light source 19 and the light receiver 21 are preferably greater than the diameter D of the carrier cylinder including the sleeve and pressure plate in order to view the topography without moving the device 44 perpendicular to the axis 22 of the to allow carrier cylinder. In other words: the cross-section of the carrier cylinder is completely in the light curtain.

The device 44 consisting of the light source 19 and the light receiver 21 can be moved parallel to the axis 22 of the carrier cylinder (in the direction 27) in order to cover the entire working width 26. A motor 45 can be present for this purpose.

A sensor 37 can be provided, which detects the sleeve 3 and/or the pressure plate 5 using an identification feature 38 (cf. Figure 2B ).

The signals and/or data generated by the light receivers 21 are transmitted to a computer 39, preferably via a cable or a radio link, and processed further there. The computer is connected to the printing machine 8 .

Alternatively, light source 19 and light receiver 21 can also be arranged on the same side of support cylinder 1; in this case, a reflector 20 is opposite, similar to that in FIGS Figures 2A to 2C arranged.

According to an alternative embodiment, the topography is preferably recorded with a laser micrometer 44 as part of a 2D diameter determination, in which not only a single measurement line 46, but a wider (dashed) measuring strip 47 from several (dashed) measuring lines 48 are recorded. In this exemplary embodiment, the light source 19 and light receiver 21 are preferably flat and not just in the form of lines. The light source 19 can comprise a plurality of lines of light 48 each having a width of approximately 0.1 mm and a distance of approximately 5 mm from one another. In this example, the camera is preferably designed as an area camera.

the Figures 4A and 4B show a preferred embodiment of the device for measuring the topography of a printing plate 5; Figure 4A in cross section and Figure 4B in top view. According to this embodiment, the topography is preferably recorded with a laser micrometer as part of a 2D radius determination.

The device comprises a light source 19, preferably an LED light source 19, and a light receiver 21, preferably a linear LED light source 21 or a linear laser 21. The light source 19 generates a light curtain 23 and the carrier cylinder 1 with sleeve 3 and printing plate 5 generates a shadow 24.

The device consisting of the light source 19 and the light receiver 21 can preferably be moved in a direction 28 perpendicular to the axis 22 of the carrier cylinder 1 in order to direct the light curtain 23 onto the topography 13 to be measured. A motor 29 can be present for this purpose. If the light curtain 23 is wide enough and therefore covers the measuring range, the motor 29 can be dispensed with.

The signals and/or data generated by the light receivers 21 are transmitted to a computer 39, preferably via a cable or a radio link, and processed further there. The computer is connected to the printing machine 8 . Alternatively, light source 19 and light receiver 21 can also be arranged on the same side of the carrier cylinder; in this case, a reflector 20 is opposite, similar to that in FIGS Figures 2A to 2C arranged.

According to an alternative embodiment, the topography 13 is preferably recorded with a laser micrometer 44 as part of a 3D radius determination, with not just one measuring line 46 but a wider measuring strip 47 (shown in dashed lines), i.e. several measuring lines 48 being recorded at the same time. In this exemplary embodiment, the light source 19 and light receiver 21 are flat and not just in the form of lines.

According to a further alternative embodiment, the topography 13 is preferably recorded with a laser micrometer 44 as part of a 3D radius determination, with the device consisting of light source 19 and light receiver 21 preferably being able to be moved in a direction 28 perpendicular to the axis of the carrier cylinder 1 in order to Aiming the light curtain 23 at the topography 13 to be measured. A motor 29 (shown in dashed lines) can be present for this purpose.

According to an alternative embodiment, the topography 13 is preferably recorded with a laser micrometer 44 as part of a 3D radius determination, with the two latter alternative embodiments being combined.

figure 5 shows an exemplary and greatly enlarged topography measurement result of a printing plate 5 (flexographic printing form) with two printing areas 50 and two non-printing areas 51. The radial measurement results for 360° at an axial location (relative to the axis of the carrier cylinder) are shown. The non-printing areas can have been produced by etching, for example, and can therefore have a smaller radius than the printing areas.

The illustration also shows an enveloping radius 52 or an envelope 52 of those points of the pressure plate 5 with the largest radius, i.e. the highest elevations of the topography 13 at the axial location.

The point 53 of the printing plate 5 is a printing point, since this would have sufficient contact with the printing material and the ink-transferring anilox roller in printing operation with a normally set pressure or print infeed between the printing plate 5 and the printing material 11 or transport cylinder 17. Normally set pressure produces a so-called kiss print, in which the printing plate just touches the substrate and in which the flexo printing dots are not significantly squeezed.

The point 54 is a point which would just about print in the printing operation with the pressure set normally, since it would just about still be in contact with the printing material.

The two points 55 are points that would not print, since they would not have any contact with the printing material or with the anilox roller during printing with a normally set pressure.

A computer program runs on the computer 39 and calculates the radially lowest point 56 and its radial distance 57 from the envelope 52 in the printing area 50 , for example using digital image processing. This calculation is carried out at regular intervals in the axial direction, eg from AS to BS at all measuring points, and the respective maximum of the lowest points (ie the maximum lowest value) from AS to middle and from middle to BS is determined. The two maxima or from it Computationally determined infeed values or setting values can be selected, for example, as the respective infeed/setting on AS and BS during printing, ie the cylinder spacing between the cylinders involved in printing is reduced by the infeed on AS and BS. A motor-driven threaded spindle can be used on the AS and on the BS for this purpose.

Below is a concrete numerical example:
On the one hand, the distance is deltaR=65µm and on the other, the distance is deltaR=55µm. In order for all dots 53 to 55 of the printing plate to print, 65 µm must be fed.

In all of the illustrated embodiments and the alternatives mentioned, the manufacturing-related and/or operational (due to wear and tear) concentricity of the sleeve 3 can also be measured and can be taken into account on the basis of the measurement and evaluation results during printing to improve the quality of the printed products produced. A warning can be issued if a specified concentricity tolerance is exceeded. The measurement can be carried out on smooth and porous sleeves.

Instead of light sources 19 or light emitters 19 (which emit visible light), radar emitters 19 (with appropriately adapted receivers) can also be used within the scope of the invention.

In all of the illustrated embodiments and their named alternatives, parameters for a dynamic print infeed can also be determined and transferred to the printing press. For example, a known (eg previously measured) and available to the computer 39 delayed expansion of the deformable and/or compressible pressure points 53 to 55 made of polymer material can be taken into account. Or, a pre-determined durometer hardness of the printing plate can be used. This expansion can depend in particular on the operationally prevailing printing speed or this printing speed dependency can are taken into account. For example, at higher printing speeds, a higher pressure setting can be selected.

The printing surface of the printing plate 5 or the dot density, i.e. the locally variable density of the printing dots on the printing plate 5, (as an alternative or in addition to the printing speed) can also be taken into account: For example, with higher dot densities, a higher pressure setting can be selected and/or the dot density can be increased be used when setting the dynamic pressure adjustment.

To determine the local point density, the received light 25, ie essentially the emitted light 23 without the light 24 shadowed by the topography 13, can be used. It carries information about the topography 13 to be measured and/or its surface point density and/or its elevations.

For this purpose, a device 43 for detecting or measuring the point density, i.e. its local values, on the printing form, e.g. flexographic printing form, can also be provided, preferably a CIS scanner bar or a line camera. It can be provided, for example, based on the data obtained/calculated from the dot density determination, default values for a different pressure adjustment on AS (drive side of the printing machine) and BS (operating side of the printing machine).

Knowing the dot density of the printing plate 5 and/or the inking anilox roller 15 and/or anilox sleeve 15, the ink consumption to be expected when printing with the printing plate on a given printing material 11 can be determined by calculation. The required drying power of the dryer 10 for drying the ink on the printing material can be determined by calculation from the ink consumption. Based on the calculated, anticipated ink consumption, an ink supply to be provided can also be calculated.

A so-called channel beating pattern can also be taken into account in all of the illustrated embodiments and the alternatives mentioned. A channel runout pattern is a disturbance that occurs periodically during the operational rotation of the printing plate 5 caused by a page width or at least disturbingly wide gap or channel in the printed image, ie a disturbingly large area without printing dots, or another axial channel, which usually extends in the axial direction. The print quality can be impaired by such channels or their channel beating pattern, since the cylinders involved in printing approach and repel rhythmically due to the kiss print position in the area of the channel that recurs during rotation. In the worst case, this can lead to unwanted density fluctuations or even print failures. An existing sewer runout pattern can preferably be recorded using a CIS measuring device 43 (eg the above-mentioned swiveling or movable mirror together with the area cameras) or using an area camera and evaluated by computer and compensated for the pressure infeed required for operation. For example, on the basis of the recorded channel beating pattern, it can be predicted at which speeds or rotational frequencies of a printing press vibrations would occur. These speeds or rotational frequencies are then not used during production and are overrun, for example, when the machine is started up.

Each printing plate 5 can have an individual channel beating pattern. Channels in the printing form can have a negative impact on the print result or even lead to print failures. In order to mitigate or even eliminate channel beats, the pressure plate is checked for channels in the rolling direction. If the resonant frequencies of the printing unit 9 are known, production speeds can be calculated which are particularly unfavorable for a given printing form. These printing speeds should be avoided (so-called "no go speed").

In all of the illustrated embodiments and the alternatives mentioned, register marks (or several register marks, e.g. wedges, double wedges, dots or crosshairs) can also be detected on the printing form, e.g. using the camera 21 or 43 and downstream digital image processing, and their position measured. be stored and made available. This enables automatic adjustment of register controllers or their register sensors to the register marks or to axial positions allowed. Errors caused by the otherwise customary manual setting of the sensors can thus be advantageously prevented.

Alternatively, patterns can be captured and used to configure a register controller.

For the automatic configuration or setting of the register controller control, a camera (400, 21, 43) is used to subject an image of a flexographic printing forme (410) to digital image processing, e.g. using a computer (410), with at least one register mark (310, 311 ) is x-y localized.

This localized x-y data of the register mark can be stored for an ID or an identifier 316 of the sleeve in a digital memory 317 and made available to the flexographic printing machine or the flexographic printing unit when the sleeve is used, stating the ID.

The flexographic printing machine or the flexographic printing unit uses the register mark position data (x-y localization) to set the register rule control. The setting of the register control also means, for example, the configuration of the register marks of a print job.

For a print job, there are usually several printing units with inks or varnishes in the printing operation, in which one flexographic printing form (410) is used for each printing unit. The position data (x-y localization) of the print marks (310, 311) for e.g. two flexographic printing forms can be different.

For this purpose, the register control of the printing machine receives the position data (x-y - localization) of the print mark (310, 311) for each flexographic printing form (410) used with the identifier (316), whereby the configuration of the register marks of the print job can be composed of several flexographic printing forms (410). .

An advantageous method for configuring the register controller is that before printing an image (410) of the surface of the sleeve with the at least one flexographic printing form is captured by a camera (400) and the image is subjected to image processing, wherein at least one registration mark (310) is or are xy-located; and that it automates the adjustment of a register controller for register mark detection.

Provision can also be made to automatically position a register sensor that can be moved by a motor, in particular in the axial direction. Provision can also be made for a predetermined zero point of the angular position of a printing cylinder and/or a sleeve arranged on it to be compared with an angular value of the actual location of a printed image (e.g. glued on by hand), in particular in the circumferential direction (or of the cylinder/sleeve). An optimal starting value for the angular position of the cylinder/sleeve can be obtained from this comparison. In this way, print production can be started with reduced register deviation. The same applies to the lateral direction (or the cylinder/sleeve).

In all of the illustrated embodiments and their named alternatives, the output of the dryer 10 of the printing press 8 can also be controlled or regulated. For example, LED dryer segments can be switched off in areas where no printing ink has been transferred to the substrate, which means that advantageous energy savings and an increase in the lifespan of the LEDs are possible.

The output of the dryer 10 or the output of individual segments of the dryer for printing areas on the printing plate with a low dot density can also be advantageously reduced. This can save energy and/or extend the service life of the dryer or individual segments. Switching off or reducing can take place on the one hand in areas and on the other hand in a direction parallel and/or transverse to the axial direction of a printing plate or to the lateral direction of the printing material to be processed with it. For example, segments or modules of a dryer can be switched off in areas corresponding to gaps between printing plates (eg spaced apart, in particular glued on by hand).

In all of the illustrated embodiments and the alternatives mentioned, the respective location (on the printing plate 5) of measurement fields for print inspection systems can also be recorded and made available for further use, e.g. for setting the location of the print inspection systems.

An inline color measuring system can also be positioned in all of the illustrated embodiments and the alternatives mentioned. In order to determine the location and thus the position of the inline color measurement, image and/or pattern recognition is carried out, on the basis of which the axial position for the measurement system is determined. The inline color measurement system can be informed of free print points to allow for a free point for the calibration on the printing material.

An exemplary overall process that can be carried out with the device in a suitable embodiment is to be presented below.

• Schritt 1: Hülse 3 mit oder ohne Druckplatte 5 wird auf den mit Luft beaufschlagten Trägerzylinder 1 der Messstation 2 über das Luftkissen aufgeschoben und arretiert.
• Schritt 2: Die Hülse wird mit einer unikaten Zeichenkette 38 identifiziert. Das kann per Barcode, 2D-Code (z.B. QR-Code oder Datamatrixcode), RFID- Code oder NFC erfolgen. Schritt 3: Kamera 21 und optional das Referenzobjekt 30 werden gemäß Durchmesser (der Hülse mit oder ohne Druckplatte) positioniert.
• Schritt 4: Ermittlung der Topografie 13 der Druckplatte mit Bezugspunkt zur Achse 6 bzw. zum Achsmittelpunkt des Trägerzylinders 22, d.h. der Radien der Erhebungen/Druckpunkte 53 bis 55. Die Lichtquelle 19 und die Kamera 21 der Messeinrichtung 18 bewegen sich dabei ggf. axial und der Trägerzylinder rotiert (seine Winkelstellung ist über einen Encoder bekannt).
• Schritt 5: Durchführung eines Flächenscans, um Punktdichten, freie Druckstellen, druckende Flächen, Registermarken und/oder Messfelder für Inline-Farbmessung zu erkennen.
• Schritt 6: Anwendung eines auf einem Rechner 39 laufenden Topografie-Algorithmus und Auswertung der Flächen über den Flächen-Scan mit Erkennung von Kanalschlagmustern und mit Registermarkenfeld-Aufbau bzw. Inline-Farbmessung.
• Schritt 7: Optionale Ermittlung der Plattenhärte (in der Einheit Shore).
• Schritt 8: Anwendung eines Staub-Detektors und/oder eines Härchen-Detektors.
• Schritt 9: Speichern der Daten der Messergebnisse in einem digitalen Speicher 40.
• Schritt 10: Darstellung der Messergebnisse mit Hinweis auf Staub/Härchen bzw. eingeschlossenen Luftbläschen und/oder Anzeigen von Grenzwerten, wie z.B. Rundlauf, Exzentrizität und/oder Balligkeit.
• Schritt 11: Mögliche Messwiederholung oder Entfernen der Hülse, um eine weitere Hülse zu vermessen.

measurement process:

• Step 1: Sleeve 3 with or without pressure plate 5 is pushed onto air-loaded carrier cylinder 1 of measuring station 2 via the air cushion and locked.
• Step 2: The sleeve is identified with a unique character string 38. This can be done using a barcode, 2D code (e.g. QR code or data matrix code), RFID code or NFC. Step 3: Camera 21 and optionally the reference object 30 are positioned according to the diameter (of the sleeve with or without the pressure plate).
• Step 4: Determination of the topography 13 of the printing plate with a reference point to the axis 6 or to the center point of the axis of the carrier cylinder 22, i.e. the radii of the elevations/pressure points 53 to 55. The light source 19 and the camera 21 of the measuring device 18 may move axially and the support cylinder rotates (its angular position is known via an encoder).
• Step 5: Performing an area scan to detect dot densities, free print spots, printing areas, register marks and/or measuring patches for inline color measurement.
• Step 6: Application of a topography algorithm running on a computer 39 and evaluation of the areas via the area scan with recognition of channel beat patterns and with register mark field structure or inline color measurement.
• Step 7: Optional determination of the panel hardness (in Shore units).
• Step 8: Application of a dust detector and/or a hair detector.
• Step 9: Saving the data of the measurement results in a digital memory 40.
• Step 10: Presentation of the measurement results with reference to dust/hairs or enclosed air bubbles and/or indication of limit values such as concentricity, eccentricity and/or crowning.
• Step 11: Possible to repeat the measurement or remove the sleeve to measure another sleeve.

• Schritt 1: Hülse 3 mit Druckplatte 5 wird auf den mit Luft beaufschlagten Druckzylinder 16 der Druckmaschine 8 über das Luftkissen aufgeschoben und arretiert.
• Schritt 2: Die Hülse wird mit ihrer unikaten Zeichenkette 38 vom jeweiligen Druckwerk 9 bzw. eines dortigen Sensors identifiziert. Das kann per Barcode, 2D-Code (z.B. QR-Code oder Datamatrixcode), RFID-Code oder NFC erfolgen.
• Schritt 3: Druckwerk bzw. Druckmaschine holt sich die gespeicherten Daten zu der zugehörigen identifizierten Hülse/Druckplatte.

set-up process:

• Step 1: sleeve 3 with printing plate 5 is pushed onto the air-loaded pressure cylinder 16 of the printing machine 8 via the air cushion and locked.
• Step 2: The sleeve is identified with its unique character string 38 by the respective printing unit 9 or a sensor located there. This can be done using a barcode, 2D code (e.g. QR code or data matrix code), RFID code or NFC.
• Step 3: The printing unit or printing machine fetches the stored data for the associated sleeve/printing plate that has been identified.

• Schritt 1: Zustellung des so genannten "Kissprints" (Einstellung der Pressung bzw. des Arbeitsdrucks) für Druckzylinder 16 und Rasterzylinder 15 z.B. anhand Topografie, Rundlauf und Bedruckstoffdaten für einen optimalen Druckpunkt. Durchmesser bzw. Radius werden ermittelt. Durchmesser bzw. Radius sind aus Messung bekannt.
• Schritt 2: Berechnung des Vorregisters anhand von Registermarken-Daten auf der Druckplatte bzw. Hülsen-Bezugspunkt.
• Schritt 3: Einstellung der dynamischen Druckzustellung anhand von ermittelten Punktdichte-Werten und bedruckter Fläche und Geschwindigkeit und optional des Bedruckstoffs. Optionale Berücksichtigung der Plattenhärte (in der Einheit Shore).
• Schritt 3: Einstellung der optimalen Materialbahn-Geschwindigkeit z.B. anhand der Berechnung von ermittelten Resonanzfrequenzen des Druckwerks zu Druckplatte durch die Kanalschlagmuster-Erkennung.
• Schritt 5: Einstellung der optimalen Trocknungsleistung (UV oder Heißluft) anhand von Punktdichte-Werte und bedruckter Fläche, sowie Rasterzylinder-Daten (Schöpfvolumen etc.) optional dynamisch an die Warenbahngeschwindigkeit angepasst.
• Schritt 6: Berechnung des Farbverbrauchs anhand von Punktdichte-Werte und bedruckter Fläche, sowie Rasterzylinder-Daten (Schöpfvolumen etc.).
• Schritt 7: Reduzieren oder Ausschalten von LED-UV-Trockner-Sektionen an Stellen, an denen sich eine geringe Punktdichte auf der Druckplatte befindet bzw. an denen keine Trocknung benötigt wird, um auf diese Weise Energie zu sparen und die Lebensdauer der LED-Lampen zu erhöhen.
• Schritt 8: Vollautomatische Einstellung des Registerreglers anhand der gewonnen Registermarkendaten, z.B. Markenkonfiguration und automatische, axiale Positionierung des Registersensors.
• Schritt 9: Einstellen der Mess-Position für die spektrale Inline-Messung und Druckinspektion der gedruckten Farben, Informationen über Ort bzw. Messposition.

Setting process:

• Step 1: Delivery of the so-called "kiss prints" (adjustment of the pressure or the working pressure) for the printing cylinder 16 and the anilox cylinder 15, for example using topography, concentricity and printing material data for an optimal printing point. Diameter or radius are determined. Diameter and radius are known from measurements.
• Step 2: Calculation of the pre-register using register mark data on the printing plate or sleeve reference point.
• Step 3: Setting the dynamic print infeed based on determined dot density values and printed area and speed and optionally the printing material. Optional consideration of the plate hardness (in the Shore unit).
• Step 3: Setting the optimum material web speed, eg based on the calculation of determined resonant frequencies of the printing unit to the printing plate through channel beat pattern recognition.
• Step 5: Setting the optimal drying performance (UV or hot air) based on dot density values and printed area, as well as anilox cylinder data (cupping volume, etc.) optionally dynamically adapted to the web speed.
• Step 6: Calculation of ink consumption based on dot density values and printed area, as well as screen cylinder data (cupping volume, etc.).
• Step 7: Reduce or switch off LED UV drying sections in places where there is a low density of dots on the printing plate or where drying is not needed, thus saving energy and the lifespan of the LED lamps to increase.
• Step 8: Fully automatic setting of the register controller using the register mark data obtained, eg mark configuration and automatic, axial positioning of the register sensor.
• Step 9: Setting the measurement position for the spectral inline measurement and print inspection of the printed colors, information about the location or measurement position.

figure 6 shows a captured image 410 of a sleeve 300 and, by way of example, two flexographic printing forms 301 and 302. The image is preferably captured or generated by a camera 400, in particular in a measuring station 2. The image can be transmitted to a computer 401. The computer 39 can do this Figure 2a be. The image can be subjected to computational image processing. Information or data can be obtained in the process. This data can be stored for an ID or an identifier 316 of the sleeve in a digital memory 317 and made available to the flexographic printing machine when the sleeve is used, stating the ID.

A detected area 303 with a high point density and a detected area 304 with a low point density are shown as an example. The areas can be image-processed recognized and separated and preferably color coded. Knowing the local dot densities of the entire flexographic printing forme 301 (and the additional flexographic printing forme 302) can be used to calculate a preset value for the so-called pressure adjustment, i.e. for setting the contact pressure between the flexographic printing cylinder and the impression cylinder (and/or anilox roller) when using the sleeve.

A captured channel 305 is also shown as an example. There are no (or essentially no) printing elevations of the flexographic printing forme 301 in the area of the channel 305. The channel 305 extends primarily in the axial y-direction and due to its y-length (and x- Width) critical with regard to possible channel impacts when passing through the printing gap and thus with regard to possible disturbing vibrations when operating the flexographic printing machine. The gaps 306 and 307, which are also shown as examples, are not critical in this regard due to their dimensions and/or adjacent/adjacent printing locations 307a. The same applies to the gap 308 between the two flexographic printing forms 301 and 302 which are mounted at a distance from one another (e.g. glued to the sleeve 300). However, the gap 309 between the front and rear edges of the flexographic printing form 301 can be critical. Critical gaps are identified by computation and preferably identified as channels.

A register mark 310 and a register mark 311 are also shown by way of example. Likewise, color measuring fields 312 and 313. In the example shown, the marks and fields are arranged in respective control strips 314 and 315. The marks and fields are preferably also captured by the camera 400 and recognized and separated by image processing. Your determined position data (x-y localization) are saved to the sleeve ID 316.

A so-called error mark 318 for detecting an assembly error of a flexographic printing form or several flexographic printing forms on the sleeve or on several sleeves is also shown as an example. Their position data is also saved for the sleeve ID 316.

figure 6 Figure 12 also shows a sensor 402. The sensor 402 may be a register sensor and/or a spectrometer. This is arranged in the flexographic printing unit of the flexographic printing machine and directed to the printing material web 11. The sensor is connected to a computer 403 and can be moved by a motor (by means of the motor 404) in the axial y-direction 405 and can therefore be positioned automatically. Using the data generated from the image 410 and making it available to the printing machine when using the sleeve 300, the sensor can move along the printing material 11 to the y-position of a mark 310, 311 to be printed and to be detected and/or the same or another Sensor in the field 312, 313 z. B. for color inspection with a spectrometer along the printing material 11 are positioned. The sensor transmits the data generated by the sensor to the computer 403 , which can be identical to the computer 401 and/or to the computer 39 .

Reference List

1

carrier cylinder

2

measuring station

3

sleeve

3a

ID of the sleeve

4

duct tape

5

Printing plate or flexographic printing form

5a

ID of the printing plate or flexographic printing form

6

Rotating body or flexographic printing form

7

first engine

8th

Printing machine or flexographic printing machine

9

Printing unit or flexographic printing unit

10

dryer

11

substrate

12

measuring rings

13

Elevations/Topography

14

surface

15

Anilox roller/anilox cylinder

15a

ID of the anilox roll/cylinder

16

pressure cylinder

17

Impression cylinder/printing material transport cylinder

18

measuring device

19

Radiation sources, in particular light sources

20

reflector or mirror

21

Radiation receivers, in particular light receivers, e.g. cameras

22

axis of rotation

23

Light curtain/emitted light

24

shadowing

25

reflected light

26

working width

27

axial direction

28

direction of movement

29

second engine

29b

another second engine

30

Reference object/line-like object, especially thread/string/knife/bar

31

reference line

32

Distance

33

lateral surface

34

Unit

35

circumferential direction

36

shadowing

37

sensor

38

Identification feature or ID

39

digital calculator

39b

another digital calculator

40

digital storage

41

drive side (AS)

42

Operating side (BS)

43

Device for detecting the point density

44

laser micrometer

45

third engine

46

measuring line

47

gages

48

several measurement lines

50

printing area

51

non-printing area

52

enveloping radius/envelope

53

printing point of the printing plate

54

point of the printing plate that is just about to be printed

55

non-printing point of the printing plate

56

deepest point

57

radial distance

58

marking agent

59

Measuring field for measuring shore hardness

60

engine

61

cones

62

Device for recording the ID

300

sleeve

301

flexographic form

302

Another flexographic form

303

Area of high point density

304

Area of low dot density

305

channel

306

Gap, non-printing spot

307

Gap, non-printing spot

307a

printing place

308

Gap between flexographic printing forms

309

gap

310

registration mark

311

registration mark

312

color patch

313

color patch

314

control strips

315

control strips

316

ID

317

Storage

318

error mark

400

camera

401

computer

402

sensor

403

computer

404

engine

405

direction of movement

410

picture

R

radial distance

D

diameter

x

direction (circumferential direction)

y

direction (axial direction)

Claims (29)

Method for operating a flexographic printing machine, with a printing cylinder (16) carrying a sleeve (3) with at least one flexographic printing form (5) or with a flexographic printing cylinder and an impression cylinder (17), the print register of the flexographic printing form or the flexographic printing cylinder being transferred to a further flexographic printing form or is set to a further flexographic printing cylinder and/or the color density is set and/or a color inspection is carried out using a sensor (402),
characterized, that before printing, an image (410) of the surface of the sleeve is captured by a camera (400) using the at least one flexographic printing forme and the image is subjected to image processing, with at least one register mark (310) and/or at least one color measuring field (312) xy - will be localized; and that before the setting, a sensor (402) for detecting the register mark is automatically moved to the y position of the register mark and the register mark is detected and/or that before the setting, a sensor (402) for detecting the color measurement field is automatically moved to the y - the position of the color patch is moved and the color patch is captured, and that before printing, at least one image (410) of the surface of a plurality of sleeves with a plurality of flexographic printing forms is captured by at least one camera (400) in order to configure a register controller of the flexographic printing machine, and that the image is subjected to digital image processing, with at least two register marks (310, 311) are xy-located and that using the xy-located register mark position data, configuring the register controller for detecting register marks is automated. Method according to claim 1,
characterized,
that the x-direction is the circumferential direction of the sleeve and the y-direction is related to it perpendicular direction of the sleeve, ie the axial direction of the sleeve. Method according to one of the preceding claims,
characterized,
that the picture covers the entire circumference and working width of the sleeve. Method according to one of the preceding claims,
characterized,
that the image processing includes a step of computational pattern recognition. Method according to claim 4,
characterized,
that a predetermined pattern of a register mark is searched for in the computational pattern recognition. Method according to claim 4 or 5,
characterized,
that a predetermined pattern of a color measuring field is searched for in the computational pattern recognition. Method according to claim 5 or 6,
characterized,
that the register mark and/or the color measurement field is or are part of a control strip (314). Method according to one of the preceding claims,
characterized,
that the flexographic printing machine comprises a flexographic printing unit and at least one further flexographic printing unit, the flexographic printing unit comprising the impression cylinder and the impression cylinder and the further flexographic printing unit comprising an additional impression cylinder and an additional impression cylinder, the further Pressure cylinder carries a further sleeve with at least one further flexographic printing form. Method according to claim 8,
characterized,
that the pressure cylinder and the further pressure cylinder comprise a respective pin (61) on their respective outer surface at a respective pin position in the x-direction. Method according to claim 9,
characterized,
that the sleeve and the further sleeve comprise on their respective inner surface a respective groove in the y-direction for the respective pin. Method according to claim 8, 9 or 10,
characterized,
that the sleeve and the further sleeve are each marked with a machine-readable ID (3a, 5a, 38, 316). Method according to claim 11,
characterized,
that the ID is designed as a unique identifier for the sleeve. Method according to claim 12,
characterized,
that the identifier comprises several digits and/or letters and/or special characters. Method according to one of claims 8 to 13,
characterized,
that the x-coordinates and the y-coordinates of both sleeves or data derived therefrom together with the respective ID of the sleeves are transmitted indirectly to the flexographic printing machine by the x-coordinates and the y-coordinates of both sleeves or therefrom derived data can be cached together with the respective ID of the sleeves and retrieved by the flexographic press for printing with the sleeves. Method according to one of the preceding claims,
characterized,
that adjusting the pressure register includes controlling or regulating the pressure register. Method according to one of the preceding claims,
characterized,
that adjusting the color density includes controlling or regulating the color density. Method according to one of the preceding claims,
characterized,
that the register mark, the color measuring field or another mark (318) is designed as an error mark (318) for detecting an assembly error of a flexographic printing forme or several flexographic printing formes on the sleeve or on several sleeves. Method according to claim 17,
characterized,
that another mark is designed as an error mark for detecting an xy positioning error of a sleeve on a flexographic printing cylinder. Method according to claim 17 or 18,
characterized,
that an xy-position of the error mark is detected by sensors and compared with the xy-position of the register mark by computation and an xy-positioning error is determined therefrom by computation. Method according to one of the preceding claims,
characterized,
that to configure the register regulator in the event that on one sleeve several Register marks are xy-located, one of these register marks is selected from the recorded data by computation. Method according to claim 20,
characterized,
that to configure the register controller of the flexographic printing machine, it is derived from the recorded data and used which register mark of the register mark configuration is printed in which printing unit. Flexographic printing machine, with at least one flexographic printing unit - comprising a printing cylinder carrying a sleeve with at least one flexographic printing forme or a flexographic printing cylinder, an impression cylinder and an anilox roller - the flexographic printing machine being operated for printing a printing material with flexographic printing ink according to one of the preceding methods,
characterized,
that the flexographic printing machine comprises at least one servomotor (404) for adjusting the y-position of the sensor. Flexographic printing machine according to claim 22,
characterized,
that the sleeve carries at least two flexographic printing forms with the same or different print motifs. System of a flexographic printing machine according to claim 22 or 23 and a measuring device for acquiring an image of a sleeve,
characterized,
that the measuring device (2, 18, 400) captures the image (410) of the sleeve using camera technology. System according to claim 24,
characterized,
that the sleeve is marked with a machine-readable ID (3a, 5a, 38, 316). A sleeve for a flexographic printing forme, the sleeve being marked with a machine-readable ID, for use in a method according to any one of claims 1 to 21 or for use in a flexographic printing machine according to any one of claims 22 or 23 or for use in a system according to any one of claims 24 or 25,
characterized,
that the machine-readable ID (3a, 5a, 38, 316) is read out by machine and stored on a computer (39, 39b, 317, 401, 403) for retrieval. Sleeve for a flexographic printing form according to claim 26,
characterized,
that the marking with the machine-readable ID takes place using a marking means (58). Method for operating a flexographic printing machine, with at least two printing cylinders - each carrying a sleeve with at least one flexographic printing forme - wherein the print register of the flexographic printing forms is adjusted to one another and a sensor for detecting register marks is used,
characterized,
that before printing, a respective image of the surfaces of the sleeves is captured by a camera and the respective image is subjected to digital image processing, with a total of at least two register marks being xy-localized, and that before the adjustment of the sensor is automated to the y-position of the register marks is moved and register marks are sensed and that using the xy-located register mark position data automates configuring the register controller to sense register marks. Method according to claim 28,
marked by
the respective characteristic feature of one of claims 2, 3, 4, 5, 15, 20 or 21.

Images