DE102008023936A1 - Profile lettering detecting method for tire of motor vehicle i.e. automobile, in assembly plant for complete wheel set, involves carrying out optical detection of profile lettering on tire side surface and transporting tire away from camera - Google Patents

Abstract

The method involves transporting a tire (3) to a camera (10) and bringing the tire to a detection position of the camera. The tire is rotated around a middle axis at a determined rotation angle, where the rotation takes place either continuously or with an intermediate stop. The optical detection of a profile lettering (1) on a side surface (2) of the tire is carried out by the camera, where the side surface or a part of the side surface is illuminated with a light source (11) i.e. laser. The tire is transported away from the camera. An independent claim is also included for a profile lettering detecting device comprising a camera.

Description

Technical area:

The The invention relates to a method and a device for reading a profile font on a surface, in particular on at least one of the side surfaces of a tire, z. B. a car tire.

State of the art:

The DE 10 2005 024 594 A1 discloses a method for automatically detecting bar code profiles or braille in the form of a pattern of protrusions or depressions, e.g. As a pattern of pimples, on or in a surface. According to the teaching of DE 10 2005 024 594 A1 a strip of the surface is illuminated by means of a light source, and the illuminated strip is detected by means of a camera in a viewing direction, which extends obliquely to the lighting plane spanned by the illuminated strip and the light source, and imaged in the image plane of the camera, so that of the illuminated stripe sweeps or depressions in the camera image of the strip as bulges show. The camera image of the strip is evaluated by means of image processing, wherein automatically from the height of the bulges on the height of the elevations or from the depth of the bulges on the depth of the wells is closed.

In usually have tires, especially car tires, on one or profiled writing on both of its side surfaces, d. H. a such writing, whose characters are either elevations on the side surface or Form depressions in the same.

The Profile writing on the side surface of tires follows in the rule of the ring shape of the tire, d. H. the signs are mostly not in a straight line, but arranged along a circular line.

In In many cases, the profile font forms on the side surfaces of tires a so-called dot code. A typical dot code on a side surface of a tire shows manufacturer and factory, Tire size, tire type and calendar week and the year of manufacture of the tire. They are usually the manufacturer and the work by two letters and / or numbers clearly defined. Determining the tire size usually takes place manufacturer-specific also by means of two letters and / or Numbers. Between three and four letters and / or numbers will be needed to classify the tire type manufacturer-specific. The calendar week and the year are usually by four numbers called.

Of Further is usually the so-called tire identification on a Side surface of a tire displayed in the form of profile font. The tire identifier usually provides three numbers the width of the tire. This is usually due to a slash of two Numbers separated, which mark the cross-section of the tire. Two more numbers usually affect the diameter of the too the rim that fits the tire. The carcass carrying capacity becomes indicated by usually two more numbers. After all is usually a letter for the so-called Speed index.

dot codes of tires of the same manufacture and of the same place of manufacture could be stored with data entry in the database become. This measure is a reliable storage possible. It could also tire identifications of Tires of the same manufacture and of the same place of manufacture Entry date are stored in a database.

That from the DE 10 2005 024 594 A1 known method is not or only with considerable difficulty and at the expense of a considerable loss of resolution and speed applicable to capture z. Example of profiling on the side surface of a car tire, because this method is not intended to capture alphanumeric characters on the one hand and on the other hand, the tire would have to be detected over its entire diameter, so that the size of the document to be detected would be very small compared to the field of view of the camera , and thirdly, a capture of the profile font with the method of DE 10 2005 024 594 A1 made impossible or at least very difficult by the crowning of the tire.

From the DE 101 45 522 A1 For example, a method of inspecting an object for information that is in relief on the object is known. In this case, initially a height profile of the object is provided. This is edited using elevation changes to highlight the relief in a rendered representation. This is then evaluated by means of optical character recognition.

Technical task:

In view of the almost unmanageable variety of tire types and subtypes, when detecting the exact type of tire by persons who are supposed to read and document the profile writing on the tire side surfaces by eye, the risk of error and confusion is very high. However, if a vehicle z. B. is equipped on the basis of such confusion with an unsuitable or improper tire type, creates an enormous Sicherheitsri siko. The invention is therefore based on the object to address this problem. It should be created with little effort, a method and apparatus for rapid, reliable and high-resolution detection of existing from alphanumeric characters and / or graphic characters or symbols profile font on a side surface of a tire, in particular, then a detection of the font without loss of resolution is to be possible if the characters to be detected are not along a straight line, but, as usual in tires, arranged along a circle and the side surface of the tire is also curved.

Disclosure of the invention and its advantages:

• A1 The object is achieved by a method for capturing a profile font on at least one the side surfaces of a tire, in particular a motor vehicle tire, with the following steps: a) Transporting the tire to at least one camera, b) Spend the tire in a Detection position of the at least one camera, c) rotate the tire about its central axis by a certain angle of rotation, the rotation being either continuous or at least one Intermediate stop, d) optical detection of the profile font during step c) by means of the at least one camera, e) Carrying away the tire.

The Transport the tire in accordance with the step a) can be made in particular by promoting the same be and takes place preferably by means of a conveyor belt or roller conveyor. Likewise, the way can transport of the tire according to step e) in particular by Carrying away the same are made and preferably takes place by means of a conveyor belt or a roller conveyor. In this way, the profile font of numerous tires can successively very rationally in routine routine operation. According to a variant, the transport is carried forward and / or the way of transporting the tire by rolling.

The Detection position is chosen so that at least one Part of the profile font either already at the beginning of step c) in the field of vision of the camera or during the step c) in the field of vision of the camera device or the field of view the camera goes through.

• A2 Vorzugsweise wird die mindestens eine Kamera bzw. werden die Kameras während des Schrittes d) weder bewegt noch verschwenkt. Vor Beginn oder nach Ende des Schritts d) wird die Kamera gemäß einer Variante des Verfahrens in einer zur Mittelachse des Reifens parallelen Richtung verfahren, beispielsweise zum Zweck der Justierung des Abstandes Kamera-Seitenfläche in Abhängigkeit von der Breite des Reifens.
• A3 Vorzugsweise wird der Rotationswinkel im Schritt c) mittels wenigstens eines Drehgebers oder Winkelcodierers digital erfasst.
• A4 Vorzugsweise wird die Seitenfläche oder ein Teil derselben mit einer Lichtquelle, insbesondere Laser, beleuchtet.
• A5 Vorzugsweise wird das Licht der Lichtquelle senkrecht, quer oder schräg zur optischen Achse der Kamera auf die Seitenfläche gestrahlt. Hierdurch kann erreicht werden, dass sich Erhebungen oder Vertiefungen auf der Seitenfläche des Reifens im Kamerabild des Streifens als Ausbuchtungen zeigen, was die Erfassung der Profilschrift erleichtern kann.
• A6 Vorzugsweise werden zur Durchführung des Schrittes d) nacheinander eine Mehrzahl oder Vielzahl von verschiedenen jeweils begrenzten Abschnitten der Seitenfläche mittels der Kamera als Einzelbilder abgebildet und die Einzelbilder gespeichert. Die Einzelbilder können softwaremäßig zu einem Gesamtbild kombiniert werden.
• A7 Vorzugsweise wird im Schritt d) jedes Einzelbild während jeweils eines Zwischenhaltes aufgenommen. Gemäß einer anderen Variante werden die Einzelbilder aufgenommen, ohne die Rotation des Reifens anzuhalten.
• A8 Vorzugsweise beträgt im Schritt c) der Rotationswinkel wenigstens 360°. Vozugsweise erfassen alle Einzelbilder zusammen die gesamte auf der Seitenfläche vorhandene Profilschrift.
• A9 Vorzugsweise weisen die im Schritt c) als Einzelbilder abgebildeten begrenzten Abschnitte der Seitenfläche jeweils die Form eines quer zur Rotationsrichtung verlaufenden Streifens auf. Die Streifen sind bevorzugt sehr schmal, beispielsweise kann die Ausdehnung der Streifen quer zur Roationsrichtung des Reifens die Ausdehnung in Rotationsrichtung des Reifens um das 5-fache oder das 10-fache oder das 50-fache oder das 200-fache übersteigen. Die Ausdehnung der Streifen quer zur Roationsrichtung des Reifens kann z. B. 200 mm, die Ausdehnung in Rotationsrichtung des Reifens 1 mm betragen.
• A10 Vorzugsweise werden die Einzelbilder erzeugt indem ein quer zur Rotationsrichtung des Reifens verlaufender, im Blickfeld der Kamera liegender Streifen der Seitenfläche mittels der Lichtquelle beleuchtet wird, so dass während des Schrittes c) wenigstens ein Teil der Seitenfläche auf Grund der Rotation des Reifens von dem beleuchteten Streifen überstrichen wird, und in Zeitabständen der jeweils in dem beleuchteten Streifen liegende Abschnitt der Seitenfläche mittels der Kamera als Einzelbild abgebildet wird. Der beleuchtete Streifen ist bevorzugt sehr schmal, besispielsweise kann die Ausdehnung des Streifens quer zur Roationsrichtung des Reifens die Ausdehnung in Rotationsrichtung des Reifens um das 5-fache oder das 10-fache oder das 50-fache oder das 200-fache übersteigen.
• A11 Vorzugsweise wird der beleuchtete Streifen mittels der Kamera in einer Blickrichtung, welche schräg zur der von dem beleuchteten Streifen und der Lichtquelle aufgespannten Beleuchtungsebene verläuft, abgebildet, so dass von dem beleuchteten Streifen überstrichene Erhebungen oder Vertiefungen sich im Kamerabild des Streifens als Ausbuchtungen zeigen.

The tire may be mounted on a rim during the course of the process and may in this case be inflated, ie stand under internal pressure.

• A2 Preferably, the at least one camera or the cameras are neither moved nor pivoted during step d). Before or after the end of step d), according to a variant of the method, the camera is moved in a direction parallel to the center axis of the tire, for example for the purpose of adjusting the distance between the camera side surface and the width of the tire.
• A3 Preferably, the rotation angle is detected digitally in step c) by means of at least one rotary encoder or angle encoder.
• A4 Preferably, the side surface or a part thereof is illuminated with a light source, in particular laser.
• A5 Preferably, the light of the light source is radiated onto the side surface perpendicularly, transversely or obliquely to the optical axis of the camera. In this way it can be achieved that elevations or depressions on the side surface of the tire in the camera image of the strip show as bulges, which can facilitate the detection of the profile font.
• A6 Preferably, in order to carry out step d), a plurality or a plurality of different respectively limited sections of the side surface are successively imaged as individual images by means of the camera and the individual images are stored. The individual pictures can be combined by software to form an overall picture.
• A7 Preferably, in step d) each frame is recorded during each intermediate stop. According to another variant, the individual images are recorded without stopping the rotation of the tire.
• A8 Preferably, in step c) the angle of rotation is at least 360 °. Preferably, all individual images together capture the entire profile font present on the side surface.
• A9 Preferably, the limited portions of the side surface depicted as individual images in step c) each have the shape of a strip running transversely to the direction of rotation. The strips are preferably very narrow, for example, the extent of the strips transverse to the direction of rotation of the tire may exceed the extent in the direction of rotation of the tire by 5 or 10 times, or 50 times or 200 times. The extension of the strips transversely to the direction of rotation of the tire can, for. B. 200 mm, the extension in the direction of rotation of the tire 1 mm.
• A10 Preferably, the individual images are generated by a transversely to the rotational direction of the tire, lying in the field of view of the camera lying strip of the side surface is illuminated by the light source, so that during the step c) at least a part of the side surface due to the rotation of the tire of the be illuminated strip is swept over, and at intervals of each lying in the illuminated strip portion of the side surface is imaged by means of the camera as a single image. The illuminated strip is preferably very narrow, for example, the extent of the strip transverse to the direction of rotation of the tire may exceed the extent in the direction of rotation of the tire by 5 or 10 times, or 50 times or 200 times.
• A11 Preferably, the illuminated strip is imaged by means of the camera in a viewing direction which runs obliquely to the lighting plane spanned by the illuminated strip and the light source, so that elevations or depressions swept by the illuminated strip show as bulges in the camera image of the strip.

• A12 Vorzugsweise werden die Einzelbilder miteinander zu einem Gesamtbild kombiniert. Das Gesamtbild erfasst vorzugsweise die gesamte auf der Seitenfläche des Reifens vorhandene Profilschrift.
• A13 Vorzugsweise ist die Kamera an einen Computer angeschlossen, wobei das Kamerabild oder die Einzelbilder oder das Gesamtbild den Computer eingelesen und dort mittels Bildverarbeitung ausgewertet werden.
• A14 Vorzugsweise wird zur Erkennung der Profilschrift mittels der Bildverarbeitung eine Graustufenanalyse oder Graustufenbewertung durchgeführt.
• A15 Vorzugsweise wird zum Zweck der Erkennung des Bedeutungsinhalts von Zeichen der Profilschrift mittels Bildverarbeitung ein OCR-Verfahren durchgeführt wird, so dass der Inhalt der Profilschrift zumindest teilweise mit Hilfe von Bildverarbeitung gelesen wird. Insbesondere kann mittels des OCR-Verfahrens z. B. jedem erkannten Zeichen der Profilschrift ein ASCII-Zeichen zugeordnet werden. Das dem Zeichen der Profilschrift zugeordnete ASCII-Zeichen entspricht dann dem Bedeutungsinhalt dieses Zeichens der Profilschrift.
• A16 Vorzugsweise wird das Ergebnis des OCR-Verfahrens in einer Datenbank gespeichert.
• A17 Vorzugsweise sind in der Datenbank alle zulässigen Profilschrift-Inhalte hinterlegt, wobei das Ergebnis des OCR-Verfahrens mit diesen zulässigen Profilschrift-Inhalten verglichen wird und ein Alarmsignal ausgelöst wird, wenn das Ergebnis des OCR-Verfahrens mit keinem der in der Datenbank hinterlegten zulässigen Profilschrift-Inhalte übereinstimmt.

These bulges represent height differences of the profile font. Different gray values (brightnesses) represent different angles of inclination of the profile font. The overall picture of the camera can thus be interpreted as a height image. Preferably, the camera is calibrated so that gray scale differences in height differences can be converted.

• A12 Preferably, the frames are combined together to form an overall picture. The overall image preferably captures the entire profile font present on the side surface of the tire.
• A13 Preferably, the camera is connected to a computer, wherein the camera image or the individual images or the overall image are read in the computer and evaluated there by means of image processing.
• A14 A grayscale analysis or grayscale evaluation is preferably carried out by image processing for recognizing the profile font.
• A15 Preferably, for the purpose of recognizing the meaning content of characters of the profile font, an OCR method is carried out by means of image processing, so that the content of the profile font is at least partially read by means of image processing. In particular, by means of the OCR method z. For example, every recognized character of the profile font can be assigned an ASCII character. The ASCII character assigned to the character of the profile font then corresponds to the meaning content of this character of the profile font.
• A16 Preferably, the result of the OCR method is stored in a database.
• A17 Preferably, all permissible profile font contents are stored in the database, wherein the result of the OCR method is compared with these permissible profile font contents and an alarm signal is triggered if the result of the OCR method with none of the permitted profile font stored in the database Content matches.

• A18 Vorzugsweise wird als Reifen ein solcher verwendet wird, dessen Seitenflächen nach außen gewölbt und somit uneben sind. Eine solche Wölbung entsteht durch die Bombierung der Reifen und verstärkt sich, wenn der Reifen aufgepumpt wird, mit zunehmendem Innendruck. Jedoch können auch drucklose Reifen eine solche Wölbung ihrer Seitenflächen aufweisen.
• A19 Vorzugsweise wird eine Annäherungskurve für ein Radialprofil oder ein mittleres Radialprofil der Seitenfläche vorgegeben oder mit Hilfe des Computers ermittelt. Mit dem Radialprofil der Seitenfläche ist die Pfeilhöhe der Oberfläche der Seitenfläche als Funktion des Abstandes von der Reifenachse bzw. der Abstand der Oberfläche der Seitenfläche von einer zur Reifenachse senkrechten Ebene als Funktion des Abstandes von der Reifenachse gemeint.

Which profile font contents are permitted or defined as permissible, can of course be z. B. depend on what type of vehicle with the tire, which is currently undergoing the process according to the invention to be provided.

• A18 is preferably used as a tire, one whose side surfaces are curved outward and thus uneven. Such a bulge results from the crowning of the tires and, as the tire inflates, increases with increasing internal pressure. However, non-pressure tires may have such a curvature of their side surfaces.
• A19 Preferably, an approximation curve for a radial profile or a mean radial profile of the side surface is predetermined or determined with the aid of the computer. By the radial profile of the side surface is meant the arrow height of the surface of the side surface as a function of the distance from the tire axis or the distance of the surface of the side surface from a plane perpendicular to the tire axis as a function of the distance from the tire axis.

• A20 Vorzugsweise wird zur Ermittlung der Annäherungskurve das Kamerabild oder die Einzelbilder oder das Gesamtbild per Bildverarbeitung ausgewertet.
• A21 Vorzugsweise werden zur Ermittlung der Annäherungskuvre nur solche Teile des Kamerabildes oder der Einzelbilder oder des Gesamtbildes ausgewertet, auf welchen keine Teile der Profilschrift abgebildet sind.
• A22 Vorzugsweise wird zur Ermittlung der Annäherungskuvre der radiale Helligkeitsverlauf des Bildes der Seitenfläche 2 im Kamerabild oder in wenigstens einem der Einzelbilder oder im Gesamtbild per Bildverarbeitung gemessen und ausgewertet.
• A23 Vorzugsweise wird als Annäherungskurve eine Parabel der Form y = ax² + bx + c vorgegeben, wobei die Parameter a, b und c – entweder alle mittels des Computers durch Auswertung des Kamerabildes oder der Einzelbilder oder des Gesamtbildes per Bildverarbeitung ermittelt werden, – oder alle vorgegeben werden, – oder teilweise mittels des Computers durch Auswertung des Kamerabildes oder der Einzelbilder oder des Gesamtbildes per Bildverarbeitung ermittelt und teilweise vorgegeben werden.

For example, an approximation curve for a radial profile or a mean radial profile of the side surface can be determined by computer using the computer from the camera image or the individual images or the overall image by image processing. According to another variant, an approximation curve for a radial profile or a mean radial profile of the side surface is specified.

• A20 Preferably, the camera image or the individual images or the overall image is evaluated by image processing in order to determine the approximation curve.
• A21 Preferably, only those parts of the camera image or of the individual images or of the overall image are evaluated to determine the approximation, on which no parts of the profile font are mapped.
• A22 Preferably, to determine the approximation, the radial brightness profile of the image of the side surface is determined 2 measured and evaluated in the camera image or in at least one of the individual images or in the overall image by image processing.
• A23 Preferably, a parabola of the form y = ax ² + bx + c is given as the approximation curve, the parameters a, b and c - either all being determined by the computer by evaluating the camera image or the individual images or the overall image by image processing, - or all be predetermined - Or partially determined by means of the computer by evaluating the camera image or the individual images or the overall image by image processing and partially specified.

• A24 Vorzugsweise wird der Annäherungskuvre ein rechnerischer radialer Helligkeitsverlauf des Bildes der Seitenfläche 2 zugeordnet. Unter radialem Helligkeitsverlauf wird hier die Bildhelligkeit als Funktion des Abstandes von der Reifenachse, d. h. der Mittelachse des Reifens, verstanden.
• A25 Vorzugsweise wird der rechnerische radiale Helligkeitsverlauf invertiert und dem gemessenen radialen Helligkeitsverlauf der invertierte rechnerische radiale Helligkeitsverlauf überlagert, so dass die Änderungen der Helligkeit in radialer Richtung des Bildes der Seitenfläche aufgehoben oder zumindest verringert werden und auf diese Weise die Erkennbarkeit der Profilschrift verbessert und ihre automatische Erkennung eleichtert wird.
• A26 Vorzugsweise wird der Reifen vor Beginn der Rotation in die Erfassungsposition verbracht, indem gegen wenigstens zwei ortsfeste Lager-Andruckrollen geschoben oder gedrückt wird, welche sich während der Rotation auf der Lauffläche des Reifens abrollen. Der Schiebe- bzw. Druckvorgang kann z. B. mittels mindestens zwei schwenkbaren Armen erfolgen.
• A27 Vorzugsweise wird vor Beginn der Rotation eine bewegliche Gegenlager-Andruckrolle so gegen die Lauffläche des Reifens gedrückt, dass die Anduckrollen gemeinsam eine spielfreie Dreipunkt- oder Mehrpunktlagerung des Reifens bilden, innerhalb welcher der Reifen stabil gelagert und um seine Mittelachse drehbar ist, wobei sich auch die Gegenlager-Andruckrolle während der Rotation auf der Lauffläche des Reifens abrollt. Gemäß einer anderen Variante werden anstelle der Andruckrollen Gleitlager verwendet.
• A28 Vorzugsweise wird wenigstens einer der Anduckrollen während des Schrittes c) angetrieben und hierdurch der Reifen in Rotation versetzt.
• A29 Gemäß einer Variante wird als Reifen ein solcher verwendet, welcher auf einer Felge montiert ist, wobei vor Durchführung des Schrittes c) eine vorzugsweise koaxial zur Reifenachse verlaufende Antriebswelle mit der Nabe der Felge verbunden wird, und der Reifen zur Durchführung des Schrittes c) mittels eines Antriebs über die Antriebswelle in Rotation versetzt wird.
• A30 Vorzugsweise ist die Kamera oberhalb der Verbindungslinie der beiden Lager-Andruckrollen angeordnet.

In particular, the specifications may be based on an earlier measurement of one or more tires of the same type.

• Preferably, the approximation cuvette becomes a computed radial brightness gradient of the image of the side surface 2 assigned. Under radial brightness curve is here the image brightness as a function of the distance from the tire axis, ie the center axis of the tire understood.
• A25 Preferably, the arithmetic radial brightness curve is inverted and superimposed on the measured radial brightness curve of the inverted arithmetic radial brightness curve, so that the changes in brightness in the radial direction of the image of the side surface are canceled or at least reduced, thus improving the visibility of the profile font and its automatic Detection is rectified.
• A26 Preferably, before the start of the rotation, the tire is moved to the detection position by pushing or pushing against at least two fixed bearing pinch rollers which roll on the tread of the tire during rotation. The sliding or printing can z. B. by means of at least two pivotable arms.
• A27 Preferably, prior to the start of the rotation, a movable counter-pressure roller is pressed against the tread of the tire so that the pressure rollers together form a play-free three-point or multi-point bearing of the tire within which the tire is stably supported and rotatable about its central axis, as well the counter-pressure roller rolls on the tread of the tire during rotation. According to another variant, sliding bearings are used instead of the pressure rollers.
• Preferably, at least one of the pressure rollers is driven during step c), thereby rotating the tire.
• A29 According to a variant is used as the tire one which is mounted on a rim, wherein before performing step c) a preferably coaxial to the tire axis extending drive shaft is connected to the hub of the rim, and the tire for performing step c) means a drive is set in rotation via the drive shaft.
• A30 Preferably, the camera is arranged above the connecting line of the two bearing pressure rollers.

• A31 Vorzugsweise wird eine zweite Kamera verwendet, mittels welcher die andere Seitenfläche des Reifens während des Schritts c) optisch erfasst wird, so dass jede der beiden Seitenflächen des Reifens während des Schrittes c) durch je eine Kamera optisch erfasst wird. A32 Vorzugsweise ist auch die zweite Kamera an den Computer angeschlossen.
• A33 Vorzugsweise wird das erfindungsgemäße Verfahren vollautomatisch durchgeführt.
• A34 Vorzugsweise wird eine Vielzahl von Reifen nacheinander dem erfindungsgemäßen Verfahren unterzogen.
• A35 Die Aufgabe wird ferner gelöst durch eine Vorrichtung zum Erfassen einer Profilschrift auf wenigstens einer der Seitenflächen eines Reifens, insbesondere eines Kfz-Reifens, wobei die Vorrichtung imstande ist, das erfindungsgmäße Verfahren vollautomatisch durchzuführen.
• A36 Vorzugsweise ist die Vorrichtung Teil einer Fertigungsanlage für Reifen oder einer Montageanlage für Kompletträder oder eines automatisch arbeitenden Systems zur Archivierung oder Lagerung von Reifen.

This variant offers the advantage, when stationary bearing pressure rollers are used, that the camera can remain stationary, regardless of the diameter of the tire being used, because the position of the part of the side surface to be detected by the camera in this case does not or only insignificantly depends on the tire diameter. so that when moving to a different tire diameter no repositioning of the camera is required. This advantage is particularly useful when a plurality of very different, not sized by size tires are successively subjected to the inventive method.

• A31 Preferably, a second camera is used, by means of which the other side surface of the tire is detected optically during step c), so that each of the two side surfaces of the tire is optically detected by a respective camera during step c). A32 Preferably, the second camera is also connected to the computer.
• A33 Preferably, the method according to the invention is carried out fully automatically.
• A34 Preferably, a plurality of tires are consecutively subjected to the method according to the invention.
• A35 The object is further achieved by a device for detecting a profile font on at least one of the side surfaces of a tire, in particular a motor vehicle tire, wherein the device is capable of carrying out the erfindungsgmäße method fully automatically.
• A36 Preferably, the device is part of a production line for tires or a mounting system for complete wheels or an automatically operating system for archiving or storing tires.

With Help of the invention can be given in the profile font Properties of tires selected with little effort and z. B. are read into a database, with a throughput itself of large quantities of tires of all kinds Type in a short time is possible.

The inventive method and the invention Device are thus very well suited to the archiving of tire data, for use in the storage of tires or for routine use Documentation of when which vehicle fitted with which type of tire has been. Such documentation can z. B. in the context of accident cause research, for insurance reasons, for statistical purposes Investigations or for market research desirable be.

A Further application of the invention consists in controlling the allocation of the vehicle and the one to be mounted on it, tire type intended for this vehicle in new-car production; such control is already here for security reasons very useful.

The The following statements relate to variants of Invention.

Of the Invention is based on the object, a method and an apparatus for reading a profile font on a curved surface indicate the rapid and reliable recording of the Ensuring meaning content of the profile font.

The The invention further relates to a method for reading a profile font on a curved surface, in particular on a tire comprising the steps of: a) conveying the curved surface to at least one reading device, b) bringing the curved surface into a reading position, c) Rotate the curved surface under simultaneous Reading the profile font, d) Recording the meaning content of the Profiling and e) storing at least individual meaning content in a database.

The The invention further relates to a device for reading a Profile writing on a curved surface, in particular on a tire comprising a conveyor for Promote the curved surface to at least a reading device, a centering device for moving the curved surface in a reading position, a drive means for rotating the curved surface, a reading device for reading the profile font and a computer for recording the Meaning contents of the profile font and for saving at least single meaning content in a database.

According to the invention a method for reading a profile font on a curved Area, especially on a tire, the following steps on: a) conveying the curved surface to at least one reading device, b) moving the curved ones Area in a reading position, c) rotating the curved Area under simultaneous reading of the profile font, d) Capture the meaning content of the profile font and e) Save at least single meaning content in a database.

According to the invention first recognized that a profile font on a curved surface with the known devices and methods are not read in an economically meaningful way can. Furthermore, it has been recognized that by rotating the The speed of the reading process has increased enormously can be, since with each turn of the surface one already The recorded area of the area can be read again. For this, the reading device does not have to be moved and thus becomes protected from damage. It has also been recognized that the movement of the curved surface into one Reading position at fixed position of the reading device only by a Coordinate, namely the radius of curvature, of the surface is determined. In that regard, a profile font of a curved Area can be read quickly and reliably. consequently the task is solved.

The curved surface could be two seconds, preferably one second in rotation. hereby Very short cycle times are feasible. When using a reading device with high resolution and fast downstream computer with image processing system are even faster rotation times conceivable.

In front this background could be the capture of the meaning content the profile writing in 3 seconds, preferably in 2 seconds. As a result, the cycle time can also be shortened. there It is conceivable that the meaning content of the profile font after detecting is displayed on a display.

The curved surface could be through a centering device spent with at least two swivel arms in the reading position become. Such a centering device requires only one Coordinate, namely the radius of curvature of the surface, to align the surface relative to the reader. Thus, a structurally simple construction of a centering device possible. Two swivel arms can under training of an adjustable angle clearly the reading position of the curved Set surface when the arms are tangents to the surface issue. The curved surface can be like in one Pliers are moved and thereby centered. By centering the surface is in a suitable position relative to Reading device spent. The angle that the arms make becomes determined by the radius of curvature of the surface. Against this background, it is conceivable that four arms are used so that the surface is securely gripped and centered from two sides can be.

The Moving the surface through the hinged arms makes a fixed stop superfluous, on which curved surfaces can come to rest. The use of such a stop is disadvantageous because the profiled font depending on the radius of curvature different distances can be spaced from the stop. This makes a complex adjustment the reading device at different radii of curvature necessary. Pivoting arms solve this problem free displacement of the surface relative to the fixed reading device.

The reading device could be moved from a rest position to a working position, preferably in the vertical direction. This can the reading device are protected from damage during conveying and centering of the surface.

It Two reading devices could be used between where the curved surface is rotated. By this embodiment can be provided on both sides with profile font Surface can be read simultaneously.

The Meaning content of the profile font could be captured by recognizing characters of the profile font by means of an OCR software and assign meaning contents to the characters thereafter. The usage An OCR software allows computational compensation of curvature factors. Not only a lateral curvature of the surface, but also a vertical curvature in the form of a convex or concave training can be compensated.

The Capturing at least one meaning content could with a Probability of at least 99.8%. This low Fault tolerance allows the use of the archiving method and storage of products after their manufacture or further processing in a commercial enterprise.

In front This background could be considered a curved surface used a side surface of a tire of a motor vehicle become. In commercial enterprises of the tire industry or the automotive industry It is often necessary to use tires of different sizes and identify and archive types. Furthermore, that can procedures described here as part of a quality management process be used to ensure the readability of the profile font put.

It could be read a profile font, the dot codes and tire identifiers, wherein the dot codes and tire identifiers as characters show numbers and / or letter combinations which Meaning contents are assigned. This is an archiving the tire possible.

One typical dot code on a side surface of a tire shows manufacturer and factory, tire size, tire type as well as the calendar week and the year of manufacture of the tire at. The manufacturer and the factory are represented by two letters and / or Numbers clearly defined. Determining the tire size takes place manufacturer-specific likewise by means of two letters and / or numbers. Between three and four letters and / or numbers will be needed to classify the tire type manufacturer-specific. The calendar week and the year are usually by four numbers called. Preference is given to the data provided by the manufacturer and the factory, tire size and tire type of a scanned tire, stored in a database.

Of Another is the so-called tire identification on a side surface of a tire. The tire identification usually delivers by three numbers the width of the tire. This is through a Slash separated by two numbers showing the cross section of the tire mark. Two more numbers relate to the diameter of the Rim on which the tire is mounted. The carcass carrying capacity is indicated by two more numbers. Finally it stands a letter for the so-called speed index.

Prefers become the carcass carrying capacity and the speed index stored in a database.

dot codes of tires of the same manufacture and of the same place of manufacture could be stored with data entry in the database become. This measure is a reliable storage possible. It could also tire identifications of Tires of the same manufacture and of the same place of manufacture Entry date are stored in a database.

It could have a diameter of at least 550 cm be rotated. This ensures that all common tires for motor vehicles archived and can be stored. It could in particular Tires of a height of at least 110 cm are rotated.

It could be a side blow of an amount of at least 0.65 cm and an offset of at least 0.45 cm are detected. As a result, a safe installation of a tire a rim can be made sure.

According to one Variant comprises a device according to the invention for reading a profile font on a curved surface, in particular on a tire, a conveyor for Promote the curved surface to at least a reading device, a centering device for moving the curved surface in a reading position, a drive means for rotating the curved surface, a reading device for reading the profile font and a computer for recording the Meaning contents of the profile font and for saving at least single meaning content in a database.

Around Repetitions in relation to the inventive step to avoid, to the remarks on the procedure as directed.

The reading device could be a camera exhibit. In this way, the individual surveys of the profile font, namely the characters, gray values can be assigned. Lower elevations are darker and higher brighter.

The Reading device could have a lighting device. This embodiment allows the use of a lighting control, which depending on the brightness in the working space. This is always a safe reading and capturing the profile font guaranteed.

Two Reading devices could be the curved surface to look at from two sides. When using a double-sided with Profile font printed tire can in this embodiment at the same time two profile fonts are read. This will the error rate further lowered as the recorded on each page Information from a computer can be adjusted.

The Centering device could be at least two swiveling Have arms which the curved surface in spend the reading position. Two swivel arms can forming an adjustable angle clearly the reading position set the curved surface when the arms as tangents to the surface. The curved surface can be moved as in a pair of pliers and thereby centered. By centering the surface is in a suitable Position spent relative to the reading device. The angle, the forming the arms is determined by the radius of curvature of the surface. Against this background, it is conceivable that four arms are used so that the surface is securely gripped and centered from two sides can be.

The Moving the surface through the arms makes a fixed Stop superfluous, on which curved Areas can come to the plant. The usage Such a stop is disadvantageous because the profile font in Dependent on the radius of curvature different can be spaced far from the stop. This makes a complicated Adjustment of the reading device at different radii of curvature necessary. Pivoting arms solve this problem free displacement of the surface relative to the fixed reading device.

The Drive means could comprise a rotating roller which at least on a part of the curved surface rolls. This allows the surface to be driven and in rotation be offset. The rotating roller can easily contact the surface be approached or moved away from this.

According to one another variant is used as a tire such a, which mounted on a rim, wherein the drive means is a drive shaft and a motor and the drive shaft with the hub of the Connected rim and for the implementation of step c) the bearing pinch rollers applied and by means of the engine and the Drive shaft is rotated. Also according to this Variant rolls the tire thus during the step c) on the bearing pinch rollers.

The Conveyor could be designed as a conveyor belt be. Conveyor belts are prone to failure and technically mature.

Further Objectives, characteristics, advantages and applications of the The present invention will become apparent from the following description of a Embodiment with reference to the drawing. Make up all described and / or illustrated features for itself or in any combination the subject matter of the invention, regardless of the summary in individual claims or their relationship.

In The drawings illustrate by way of example and schematically

1 an inventive device for detecting a profile font on one of the side surfaces of a motor vehicle tire according to a first preferred embodiment of the invention, and

2 a tire wheel consisting of tire and rim, which is set in rotation with a drive mechanism, wherein the drive mechanism is part of a device for detecting a profile font on one of the side surfaces of a motor vehicle tire according to a second preferred embodiment of the invention.

• a) Herantransportieren des Reifens 3 auf einem Förderband F zu mindestens einer Kamera 10,
• b) Verbringen des Reifens 3 in eine Erfassungsposition mit Hilfe von zwei schenkbaren Armen 6a, 6b,
• c) Rotieren des Reifens 3 um seine Mittelachse A um einen bestimmten Rotationswinkel, wobei die Rotation entweder durchgehend oder mit wenigstens einem Zwischenhalt erfolgt und der Reifen 3 während der Rotation mittels zwei Lager-Andruckrollen 6c, 6d und einer Gegenlager-Andruckrolle 7 spielfrei dreipunktgelagert ist und die Lager-Andruckrollen 6c, 6d, 7 sich auf der Lauffläche des Reifens 3 abrollen,
• d) optisches Erfassen der Profilschrift 1 während des Schritts c) mit der Kamera 10,
• e) Wegtransportieren des Reifens 3 auf einem Förderband F'.

1 shows a first embodiment of a device according to the invention for detecting a profile font 1 on at least one of the side surfaces 2 a car tire 3 which is able to carry out the following fully automatically steps:

• a) Transporting the tire 3 on a conveyor F to at least one camera 10 .
• b) Spend the tire 3 into a detection position by means of two pivotable arms 6a . 6b .
• c) rotating the tire 3 about its central axis A by a certain angle of rotation, the rotation taking place either continuously or with at least one intermediate stop, and the tire 3 during rotation by means of two bearing pressure rollers 6c . 6d and an abutment pinch roller 7 is free of play three-point bearings and the bearing pinch rollers 6c . 6d . 7 on the tread of the tire 3 roll,
• d) optical detection of the profile font 1 during step c) with the camera 10 .
• e) carrying away the tire 3 on a conveyor belt F '.

The profile font 1 is in the present example sublime, ie their characters are in relief over the surface of the side surface 2 of the tire 3 above.

The with the inventive device of 1 feasible method according to the invention is based on the 1 further described below:
Before the start of step d), the camera can move in a direction to the center axis A of the tire 3 move parallel direction (this movement is in 1 indicated by a double arrow), for example, for the purpose of adjusting the distance of the camera 10 to the side surface 2 depending on the width of the tire 3 , of its height or of its diameter.

The side surface 2 or a part thereof by means of a light beam L, which from a light source 11 is generated, lit. The light source 11 may in particular be a laser.

For performing the step d), a plurality or a plurality of different respective limited portions of the side surface are sequentially formed 2 by means of the camera 10 as single images and the individual images stored. Between taking two frames, the tire becomes 3 each rotated by a certain angle. In step d), either each individual image is recorded during each intermediate stop, ie the rotation of the tire 3 is paused during the recording of each frame, or the frames are shot without the rotation of the tire 3 to stop.

All frames together capture the entire on the side surface 2 existing profile font 1 , After the end of step d), the individual images are combined together to form an overall image.

The camera 10 is to a computer or computer 8th connected, by means of which the camera image or the individual images or the overall image are evaluated by image processing.

Preference is given to the recognition of the profile font 1 by means of image processing a gray scale analysis or grayscale evaluation performed, ie the characters of the profile font 1 are recognized as such that their gray values or the gray values of their edges in the image of the camera 10 different from the environment. Preference is given to characters of the profile font 1 , which were thus recognized as such, subjected by image processing an OCR method, ie read. The OCR read operation can, for. For example, the character may be assigned an ASCII character. The results of the OCR method are preferably stored in a database 9 saved.

The profile font read in this way 1 can by means of the computer 8th be subjected to a check. For example, from the computer 8th be checked if the profile font 1 has the correct number of characters, or if characters of the profile font 1 contradict each other, or whether the profile font 1 Contains characters that are not contained in or contradict any provision or standard.

In the database 9 all permitted or not excluded contents of tire profile fonts can be stored so that the content of the profile font read according to the invention 1 by comparison with the contents of the database 9 be checked for acceptability and / or completeness. This procedure can also be reversed to the discovery of errors in the erfindungemäßen reading the profile font 1 , in particular in the OCR-based assignment of the characters of the profile font 1 used to ASCII characters, thus contribute to increasing the reliability of the method according to the invention.

According to one preferred variant of the invention are in particular also those Tire undergoing the process according to the invention, their side surfaces cambered, d. H. outward arched and therefore not flat. It can do this z. B. tires, which are mounted on a rim and under Pressure.

The crowning causes in general, that the radial brightness of the camera 10 supplied image of the side surface 2 is not constant, ie the brightness of the camera 10 supplied image of the side surface 2 will usually change with increasing distance from the tire central axis A.

The consequence of this is that the image background (ie the environment of the characters of the profile font 1 in the picture of the camera 10 ) is unevenly bright, causing the recognizability of the profile font by the computer 8th can be made significantly more difficult.

According to a variant of the invention, therefore, an approximation curve for a radial profile or a mean radial profile of the side surface 2 ie a curve showing the distance of the curved side surface 2 from a plane perpendicular to the tire central axis A as a function of the distance from the tire central axis A approximately specifies, given or with the help of the computer 8th determined. To determine the approximation curve, the camera image or the individual images or the overall image can be displayed processing are evaluated, or only those parts of the camera image or the individual images or the overall picture on which no parts of the profile font 1 are shown.

For this purpose, in particular the radial brightness curve of the image of the side surface 2 be measured and evaluated in the camera image or in at least one of the individual images or in the overall image by image processing. As an approximation curve, a parabola is preferably specified whose individual parameters can either be predetermined again or determined by evaluation of the camera image or of the individual images or of the overall image by image processing.

The thus obtained approximation can now be a calculated radial brightness curve of the image of the side surface 2 be assigned, ie it will be in the computer 8th a picture of the side surface 8th generated, the radial brightness curve corresponds to the approach curve. Now, the arithmetic radial brightness curve can be inverted and then superimposed on the measured radial brightness curve, so that the changes in the brightness in the radial direction of the image of the side surface 2 be canceled or at least reduced.

With this procedure, therefore, the distortion of the background brightness in the image of the side surface 2 , which is caused by the curvature of the side surface, computationally opposite to an approximately opposite equal distortion, whereby the brightness of the image background made uniform and thus the recognizability of the profile font 1 improved and their automatic detection is rectified.

2 schematically shows a tire according to a second preferred embodiment of the invention 3 and rim 12 existing complete wheel 3 . 12 , which with a drive mechanism 14 . 15 . 16 is in rotation displaceable. The drive mechanism 14 . 15 . 16 is part of a device according to the invention for detecting the profile font 1 on one of the side surfaces 2 of the vehicle tire 3 ; the remaining parts of the device are in 2 not shown.

The drive mechanism 14 . 15 . 16 includes a drive shaft 14 , a toothed disc 15 and a motor shaft 16 , Which not shown teeth in the toothed disc 15 engages and connected to a motor, also not shown. In the situation of 2 is the tire 3 on two bearing pinch rollers, not shown, whose function that of the bearing pinch rollers 6c . 6d from 1 equivalent.

The upper end of the drive shaft 14 by means of a tensioning device, not shown, to the hub 13 the rim 12 coupled. By means of the engine, the tire can be 3 over the motor shaft 16 , the toothed disc 15 and the drive shaft 14 set in rotation, the profile font 1 can be detected in the same way as above with reference to the embodiment of FIG 1 was explained. During the rotation, the tire rolls 3 on the bearing pinch rollers.

The The following statements relate to a variant of the invention.

The curved surface 2 on a tire 3 is on a conveyor belt 4 to the reading device 5 promoted. The curved surface 2 is done by centering the tire 3 spent in a reading position, the reading device 5 is fixed. After centering the area 2 becomes the reading device 5 Move vertically from a rest position to a working position. Then the curved surface becomes 2 under simultaneous reading of the profile font 1 rotated by the reading device. The curved surface 2 is rotated for one second.

The meaning content of the profile font 1 are recorded. This is done by first recognizing the profile font by an OCR software. In the process, the concave curvature of the surface becomes 2 in the direction of the reading device 5 and the lateral curvature of the surface 2 which is determined by the radius of curvature of the tire 3 is determined, calculated.

Single sign of recognized profile font 1 then meaning contents are assigned. For example, the identified letter combination NEY3 is assigned a manufacturer and a work as meaning content. The capture of the meaning content of the profile font 1 done in 2 seconds. The detection of at least one meaning content takes place with a probability of at least 99.8%.

At least single preselected meaning contents are then entered into a database with entry date 9 stored.

Regarding further advantageous embodiments and developments of the teaching of the invention on the one hand to the general part of the description and on the other hand referenced to the claims.

Industrial Applicability

The Invention is z. B. in commercial enterprises of the tire industry or the automotive industry as part of a quality management process or a warehousing process is commercially applicable.

1

profil font

2

Side surface of 3

3

tires

4

Conveyor

5

reader

6a, 6b

swing arms

6c, 6d

Bearing pressure rollers

7

Thrust bearing roller

8th

computer

9

Database

10

camera

11

light source

12

rim

13

hub

14

drive shaft

15

toothed washer

16

motor shaft

A

Central axis of 3

F

conveyor belt

L

Light beam off 11

QUOTES INCLUDE IN THE DESCRIPTION

This list The documents listed by the applicant have been automated generated and is solely for better information recorded by the reader. The list is not part of the German Patent or utility model application. The DPMA takes over no liability for any errors or omissions.

Cited patent literature

• - DE 102005024594 A1 [0002, 0002, 0008, 0008]
• - DE 10145522 A1 [0009]

Claims (36)

Method for detecting a profile font ( 1 ) on at least one of the side surfaces ( 2 ) of a tire ( 3 ), in particular a motor vehicle tire ( 3 ), comprising the following steps: a) transporting the tire ( 3 ) to at least one camera ( 10 b) Spend the tire ( 3 ) into a detection position of the at least one camera ( 10 ), c) rotating the tire ( 3 ) about its central axis by a certain angle of rotation, wherein the rotation takes place either continuously or with at least one intermediate stop, d) optical detection of the profile writing ( 1 ) during step c) by means of the at least one camera ( 10 ), e) carrying away the tire ( 3 ). Method according to claim 1, characterized in that the at least one camera ( 10 ) is not moved or pivoted during step d). Method according to one of the preceding claims, characterized characterized in that the angle of rotation in step c) by means of at least a rotary encoder or angle encoder is detected digitally. Method according to one of the preceding claims, characterized in that the side surface ( 2 ) or a part thereof with a light source ( 11 ), in particular laser, is illuminated. Method according to claim 4, characterized in that the light of the light source ( 11 ) perpendicular, transverse or oblique to the optical axis of the camera ( 10 ) on the side surface ( 2 ) is blasted. Method according to one of the preceding claims, characterized in that - to carry out step d) successively a plurality or a plurality of different respectively limited sections of the side surface ( 2 ) by means of the camera ( 10 ) are displayed as individual images, - and the individual images are stored. A method according to claim 6, characterized in that in step d) - either each frame is recorded during each intermediate stop, - or the frames are recorded without the rotation of the tire ( 3 ) to stop. Method according to one of claims 6 or 7, characterized in that in step c) the angle of rotation is at least 360 ° and all individual images together the entire on the side surface ( 2 ) existing profile font ( 1 ) to capture. Method according to one of claims 6 to 8, characterized in that in step c) imaged as individual images limited portions of the side surface ( 2 ) each have the shape of a transverse to the direction of rotation strip. Method according to one of claims 4 or 5 and according to claim 9, characterized in that the individual images are produced by - a transversely to the rotational direction of the tire ( 3 ), in the field of vision of the camera ( 10 ) lying strip of the side surface ( 2 ) by means of the light source ( 11 ) is illuminated, so that during the step c) at least a part of the side surface ( 2 ) due to the rotation of the tire ( 3 ) is swept over by the illuminated strip, and - at intervals of the portion of the side surface in each case in the illuminated strip ( 2 ) by means of the camera ( 10 ) is displayed as a single image. A method according to claims 5 and 10, characterized in that the illuminated strip by means of the camera ( 10 ) in a viewing direction which is oblique to that of the illuminated strip and the light source ( 11 ), so that the elevations or depressions swept by the illuminated strip show up as bulges in the camera image of the strip. Method according to one of claims 6 to 11, characterized in that the individual images to one another Overall picture can be combined. Method according to one of the preceding claims, characterized in that the camera ( 10 ) to a computer ( 8th ) is connected and read the camera image or the individual images or the entire image of the computer and evaluated there by means of image processing. A method according to claim 13, characterized in that for the recognition of the profile font ( 1 ) is performed by means of image processing, a gray level analysis or gray level evaluation. Method according to one of claims 13 or 14, characterized in that for the purpose of recognizing the meaning content of characters of the profile font ( 1 ) is carried out by means of image processing an OCR method, so that the content of the profile font ( 1 ) is at least partially read by means of image processing. A method according to claim 15, characterized in that the result of the OCR method in a database ( 9 ) get saved. Method according to claim 16, characterized in that in the database ( 9 ) all permissible profiled font contents are stored, the result of the OCR method is compared with these permissible profiled font contents and an alarm signal is triggered if the result of the OCR method with none of the data in the database ( 9 ) matches permitted profile font contents. Method according to one of the preceding claims, characterized in that as a tire ( 3 ) one is used whose side surfaces ( 2 ) arched outwards and are therefore uneven. Method according to one of claims 13 to 17 and according to claim 18, characterized in that an approximation curve for a radial profile or a mean radial profile of the side surface ( 2 ) or with the help of the computer ( 8th ) is determined. Method according to claim 19, characterized that for determining the approximation curve, the camera image or the individual images or the overall image evaluated by image processing becomes. A method according to claim 20, characterized in that only parts of the camera image or of the individual images or of the overall image are evaluated to determine the approximation, on which no parts of the profile font ( 1 ) are shown. Method according to one of claims 19 to 21, characterized in that for determining the approximate cuvre the radial brightness curve of the image of the side surface 2 in the camera image or in at least one of the individual images or in the Overall picture is measured and evaluated by image processing. Method according to one of claims 19 to 22, characterized in that a parabola of the form y = ax ² + bx + c is given as the approximation curve, wherein the parameters a, b and c - either all by means of the computer ( 8th ) are determined by evaluating the camera image or the individual images or the overall image by image processing, - or all are specified, - or partially by means of the computer ( 8th ) are determined by evaluation of the camera image or the individual images or the overall image by image processing and partially specified. Method according to one of claims 19 to 23, characterized in that the approximation cuvre a calculated radial brightness curve of the image of the side surface ( 2 ). A method according to claim 24, characterized in that - the computed radial brightness curve is inverted, and - the measured radial brightness curve of the inverted arithmetic radial brightness curve is superimposed, - so that the changes in the brightness in the radial direction of the image of the side surface ( 2 ) or at least reduced, - and in this way the recognizability of the profile font ( 1 ) and its automatic detection is rectified. Method according to one of the preceding claims, characterized in that the tire ( 3 ) is brought into the detection position before the start of the rotation by applying against at least two fixed bearing pressure rollers ( 6c . 6d ) is pushed or pushed, which during rotation on the tread of the tire ( 3 ). A method according to claim 26, characterized in that before the start of the rotation of a movable counter-pressure roller ( 7 ) so against the tread of the tire ( 3 ) is pressed, that the Anduckrollen ( 6c . 6d . 7 ) together a play-free three-point or Mehrpunktlagerung the tire ( 3 ) within which the tire is stably supported and rotatable about its central axis, whereby also the counter bearing pinch roller (FIG. 7 ) during rotation on the tread of the tire ( 3 ) rolls off. A method according to claim 27, characterized in that at least one of the Anduckrollen ( 6c . 6d . 7 ) is driven during step c) and thereby the tire ( 3 ) is set in rotation. Method according to one of claims 1 to 27, characterized in that as a tire ( 3 ) is used, which on a rim ( 12 ) is mounted, wherein prior to performing step c) a drive shaft ( 14 ) with the hub ( 13 ) of the rim ( 12 ) and the tire ( 3 ) for carrying out step c) by means of a drive via the drive shaft ( 14 ) is set in rotation. Method according to one of claims 27 or 28, characterized in that the camera ( 10 ) above the connecting line of the two bearing pressure rollers ( 6c . 6d ) is arranged. Method according to one of the preceding claims, characterized in that a second camera is used, by means of which the other side surface of the tire ( 3 ) is detected optically during step c), so that each of the two side surfaces of the tire is optically detected by a respective camera during step c). Method according to claims 13 and 31, characterized in that the second camera to the computer ( 8th ) connected. Method according to one of the preceding claims, characterized in that the method is carried out fully automatically becomes. Method according to one of the preceding claims, characterized in that a plurality of tires in succession a method according to one or more of Claims 1 to 33 is subjected. Device for detecting a profile font ( 1 ) on at least one of the side surfaces ( 2 ) of a tire ( 3 ), in particular a motor vehicle tire ( 3 ), characterized in that the device is capable of carrying out the method according to one or more of claims 1 to 34 fully automatically. Device according to claim 35, characterized in that that the device is part of a tire manufacturing plant or an assembly plant for complete wheels or an automatically operating system for archiving or storage of tires.