DE102021200598A1 - Process and device for creating meaningful cutting edge images - Google Patents

Abstract

The invention relates to a device (10) for analyzing a cut edge (12) of a workpiece (14). The workpiece (14) can be held in a workpiece holder to illuminate the cut edge (12) with a first light source (24) at an acute angle (w1). The illumination by the first light source (24) is preferably parallel or antiparallel to the cutting direction (16) of the cutting edge (12) up to a few degrees. The first light source (24) is preferably arranged offset parallel to the workpiece plane (18). In other words, the first light source (24) illuminates at an acute angle (w1) to a plane that extends perpendicularly to the workpiece plane (18) in the direction of the longitudinal axis of the cutting edge (12). The first light source 24 is preferably arranged offset parallel to the workpiece plane (18). The device (10) has a camera (20) whose optical axis (34) preferably extends in the workpiece plane (18). A computer can have an algorithm, in particular with a neural network, in order to analyze cutting edge images created with the camera (20). The invention also relates to a method for analyzing the cutting edge (12), in particular using such a device (10).

Description

Background of the Invention

The invention relates to a method for analyzing a cut edge of a workpiece. The invention further relates to a device for analyzing a cutting edge.

It is known to use a camera to analyze cut edges of workpieces.

the DE 10 2008 024 806 A1 discloses a method for adjusting a profile processing machine with a camera.

From the DE 29 41 815 A1 a device for automated part alignment has become known.

the DE 10 2004 050 428 A1 discloses a device for generating a plane of light for visualizing the effective direction of a working medium, for example an X-ray beam.

the DE 197 58 214 A1 discloses an optical precision measuring device for determining the edge position, the edge slope and the roughness parameters of stationary workpieces and for determining the diameter, the circular and cylindrical shape deviations in moving, rotationally symmetrical workpieces during the manufacturing process. This is done by evaluating the two-dimensional Fresnel diffraction pattern created in a distance sensor by laser illumination of object edges according to gradient, attenuation of the envelope, spatial frequency and contour lines.

From the DE 10 2017 211 680 A1 it has become known to use light planes to create a crosshair on a workpiece surface. Furthermore, it is from the DE 10 2017 211 680 A1 become known to form ring lights from LED segments.

The generic DE 10 2013 107 639 A1 discloses a processing machine with an illumination device. The lighting device can be designed in the form of a lighting ring with a plurality of LEDs which are inclined towards the optical axis of the lighting device.

object of the invention

In contrast, the object of the invention is to provide a method and a device for significantly improved analysis of a cutting edge.

Description of the invention

This object is achieved according to the invention by a method according to patent claim 1 and a device according to patent claim 10. The dependent claims reflect preferred developments.

• B) Beleuchten einer Schnittkante mit einer ersten Lichtquelle und Aufnehmen eines Schnittkantenbildes mit einer Kamera,

wobei die erste Lichtquelle senkrecht beabstandet zur Werkstückebene angeordnet ist und die Schnittkante in einem Winkel von mehr als 0° und weniger als 45° beleuchtet.The object according to the invention is thus achieved by a method for analyzing a cut edge with the method step:

• B) illuminating a cut edge with a first light source and recording a cut edge image with a camera,

wherein the first light source is arranged at a distance perpendicular to the plane of the workpiece and illuminates the cut edge at an angle of more than 0° and less than 45°.

The cut edge is thus illuminated at an acute angle in the direction of the cut or against the direction of the cut. It has been shown that both the roughness (groove formation) and the bevel of the cutting edge can be captured particularly well with the camera.

The first light source can illuminate the cutting edge at a minimum angle of more than 1°, in particular more than 3°, preferably more than 5°, particularly preferably more than 10°. The first light source can illuminate the cut edge at a maximum angle of less than 30°, in particular less than 20°.

The angle can be selected depending on the material. The bevel of the cutting edge is typically 1° to 3° for work pieces made of stainless steel, for example, and typically 5° to 10° for work pieces made of aluminum. The angle is preferably selected in such a way that the cut edge is still fully illuminated by the first light source despite the edge bevel.

In other words, the cut edge is preferably illuminated at a very acute angle.

The cutting edge image is preferably recorded frontally to the cutting edge with the camera arranged in the plane of the workpiece. In other words, when recording the cutting edge image, the optical axis of the camera is preferably in the workpiece plane.

1. A) Strahlschneiden, insbesondere Laserschneiden, des Werkstücks zum Erstellen der Schnittkante.

The following process step is particularly preferably carried out before process step B):

1. A) Beam cutting, in particular laser cutting, of the workpiece to create the cut edge.

The workpiece is preferably a metal sheet. The laser cutting is preferably carried out perpendicular to the workpiece plane.

The cut edge can be illuminated by a second light source when recording the cut edge image, the second light source being opposite the first light source, being arranged at a distance perpendicular to the workpiece plane and illuminating the cut edge at an angle of more than 0° and less than 45°.

As a result, the cut edge is illuminated both in the direction of the cut and against the direction of the cut, resulting in a more homogeneous illumination. The second light source can illuminate the cutting edge at a minimum angle of more than 1°, in particular more than 3°, preferably more than 5°, particularly preferably more than 10°. The second light source can illuminate the cut edge at a maximum angle of less than 30°, in particular less than 20°. The angle can be selected depending on the material. The angle is preferably selected in such a way that the cut edge is still completely illuminated by the second light source despite the edge bevel.

The second light source is preferably arranged on the workpiece plane mirrored to the first light source.

Before or after method step B), a cut edge image can be recorded with the camera when the light source or light sources are switched off.

When the light source or light sources are switched off, the cutting edge is only illuminated by background lighting and appears as a contour, making any burr formation on the cutting edge particularly visible.

• • Einer Frontallichtquelle, die die Schnittkante frontal, d.h. in Richtung der Werkstückebene, beleuchtet;
• • einer weiteren Frontallichtquelle, die die Schnittkante frontal beleuchtet;
• • einer Winkellichtquelle, die die Schnittkante in der Werkstückebene in einem Winkel zwischen 30° und 60° beleuchtet;
• • einer der Winkellichtquelle gegenüberliegenden weiteren Winkellichtquelle, die die Schnittkante in der Werkstückebene in einem Winkel zwischen 30° und 60° beleuchtet;
• • einer Seitenlichtquelle, die die Schnittkante in der Werkstückebene in einem Winkel von mehr als 0° und weniger als 45° beleuchtet;
• • einer der Seitenlichtquelle gegenüberliegenden weiteren Seitenlichtquelle, die die Schnittkante in der Werkstückebene in einem Winkel von mehr als 0° und weniger als 45° beleuchtet.

In addition, the crop edge may be illuminated by one or more of the following light sources when creating the crop edge image:

• • A frontal light source that illuminates the cut edge frontally, ie in the direction of the workpiece plane;
• • another frontal light source that frontally illuminates the cutting edge;
• • an angled light source that illuminates the cutting edge in the plane of the workpiece at an angle of between 30° and 60°;
• • a further angled light source opposite the angled light source, which illuminates the cutting edge in the workpiece plane at an angle of between 30° and 60°;
• • a side light source illuminating the cutting edge in the plane of the workpiece at an angle greater than 0° and less than 45°;
• • another side light source opposite the side light source, which illuminates the cut edge in the workpiece plane at an angle of more than 0° and less than 45°.

The side light source and/or the further side light source can illuminate the cutting edge at an angle of more than 1° and less than 30°, in particular at an angle of more than 2° and less than 20°.

The front light source and the further front light source are preferably designed to illuminate the cut edge in parallel. The angled light source and the further angled light source are preferably arranged mirrored about a plane of symmetry running perpendicular to the plane of the workpiece. The side light source and the further side light source are preferably arranged mirrored to one another with respect to a plane of symmetry running perpendicularly to the plane of the workpiece.

The light source(s) described can emphasize further details of the cut edge. The light sources can be of the same design. The light source(s) is/are preferably in the form of light-emitting diodes (LEDs). The light source(s) can particularly preferably be embodied in the form of high-power LEDs, in particular in the form of warm-white LEDs.

More preferably, the light sources are ±40%, in particular ±25%, preferably ±20%, particularly preferably ±15%, equidistant from the center of the cutting edge. The light sources can be arranged hemispherically around the center of the cutting edge.

The light sources can be controlled via a DigIO card or a DigIO board. This enables individual light sources to be controlled by a computer.

• • Alle Lichtquellen aus;
• • Frontallichtquelle und weitere Frontallichtquelle an, alle weiteren Lichtquellen aus;
• • Winkellichtquelle und weitere Winkellichtquelle an, alle weiteren Lichtquellen aus;
• • Frontallichtquelle, weitere Frontallichtquelle, Winkellichtquelle und weitere Winkellichtquelle an, alle weiteren Lichtquellen aus;
• • Seitenlichtquelle, weitere Seitenlichtquelle, erste Lichtquelle und zweite Lichtquelle an; alle weiteren Lichtquellen aus;
• • Seitenlichtquelle an; alle weiteren Lichtquellen aus;
• • weitere Seitenlichtquelle an; alle weiteren Lichtquellen aus;
• • erste Lichtquelle an; alle weiteren Lichtquellen aus;
• • zweite Lichtquelle an; alle weiteren Lichtquellen aus;
• • Winkellichtquelle an; alle weiteren Lichtquellen aus;
• • weitere Winkellichtquelle an; alle weiteren Lichtquellen aus;
• • Seitenlichtquelle und weitere Seitenlichtquelle an; alle weiteren Lichtquellen aus;
• • erste Lichtquelle und zweite Lichtquelle an; alle weiteren Lichtquellen aus;
• • Frontallichtquelle, weitere Frontallichtquelle und erste Lichtquelle an; alle weiteren Lichtquellen aus.

Several cutting edge images can be recorded, whereby the cutting edge is illuminated as follows - in any order - when recording the respective cutting edge images:

• • All light sources off;
• • Front light source and other front light source on, all other light sources off;
• • Angle light source and additional angle light source on, all other light sources off;
• • Front light source, other front light source, angled light source and other angled light source on, all other light sources off;
• • side light source, further side light source, first light source and second light source; all other light sources off;
• • side light source on; all other light sources off;
• • further side light source on; all other light sources off;
• • first light source on; all other light sources off;
• • second light source on; all other light sources off;
• • Angle light source on; all other light sources off;
• • another angle light source on; all other light sources off;
• • side light source and further side light source on; all other light sources off;
• • first light source and second light source on; all other light sources off;
• • Front light source, further front light source and first light source on; all other light sources off.

In this way, a meaningful set of cutting edge images can be created in order to enable a particularly accurate characterization of the cutting edge.

The creation of the cutting edge image with a camera can be carried out in a structurally particularly simple and cost-efficient manner if the camera is part of a smartphone.

The cutting edge image can be transmitted from the smartphone to a computer via a suitable interface, in particular via an Android Debugging Bridge (ADB).

• D) Zuführen des Schnittkantenbildes an ein trainiertes neuronales Netz, wobei das neuronale Netz anhand des Schnittkantenbildes die Rauigkeit, die Schnittkantenschräge und/oder die Gratbildung der Schnittkante ermittelt und ausgibt.

The method according to the invention can have the following method step:

• D) Supplying the cut edge image to a trained neural network, the neural network using the cut edge image to determine and output the roughness, the cut edge inclination and/or the burr formation of the cut edge.

• • AlexNet: Alex Krizhevsky, Imagenet classification with deep convolutional neural networks, Communications of the ACM 60.6, pg. 84-90 (2017);
• • MobileNet: Andrew G. Howard, MobileNets: Efficient Convolutional Neural Networks for Mobile Vision Applications, CoRR, abs/1704.04861, (2017);
• • Xception: Franςοis Chollet, Xception: Deep Learning with Depthwise Separable Convolutions, CoRR, abs/1610.02357, (2016).

A convolutional neural network, in particular one of the following neural networks, is preferably used as the neural network:

• • AlexNet: Alex Krizhevsky, Imagenet classification with deep convolutional neural networks, Communications of the ACM 60.6, pg. 84-90 (2017);
• • MobileNet: Andrew G. Howard, MobileNets: Efficient Convolutional Neural Networks for Mobile Vision Applications, CoRR, abs/1704.04861, (2017);
• • Xception: Franςοis Chollet, Xception: Deep Learning with Depthwise Separable Convolutions, CoRR, abs/1610.02357, (2016).

• C) Teilen des Schnittkantenbildes und Zusammenfügen zu einem quadratischen Schnittkantenbild.

The following process step is more preferably carried out before process step D):

• C) Splitting the crop edge image and merging it into a square crop edge image.

As a result of this preprocessing, the cutting edge image can be processed better, in particular for the neural network, and has a higher density of relevant information, so that the analysis quality, in particular by the neural network, is improved.

1. a) Einen Werkstückhalter, insbesondere zum Auflegen eines Werkstücks mit einer Schnittkante, wobei sich die Werkstückauflage parallel zur Werkstückebene des aufgelegten Werkstücks erstreckt;
2. b) eine Kamera zum Aufnehmen eines Schnittkantenbildes;
3. c) Eine erste Lichtquelle, wobei die erste Lichtquelle senkrecht zur Werkstückebene beabstandet und zum Beleuchten der Schnittkante in einem Winkel von mehr als 0° und weniger als 45° anordenbar ist.

The object according to the invention is also achieved by a device for analyzing a cut edge, in particular with a method described here, the device having the following:

1. a) A workpiece holder, in particular for placing a workpiece with a cutting edge, the workpiece support extending parallel to the workpiece plane of the workpiece placed thereon;
2. b) a camera for capturing a cut edge image;
3. c) A first light source, wherein the first light source is spaced perpendicularly to the workpiece plane and can be arranged to illuminate the cut edge at an angle of more than 0° and less than 45°.

The device according to the invention makes it possible to create a particularly meaningful cut edge image.

The first light source can be arranged at a minimum angle of more than 1°, in particular more than 3°, preferably more than 5°, particularly preferably more than 10°. The first light source can be arranged at a maximum angle of less than 30°, in particular less than 20°, to the cutting edge. The angle of the first light source to the cutting edge is preferably selected depending on the material.

The workpiece with the cutting edge can be part of the device. The cutting edge is particularly preferably designed as a cutting edge cut with a beam, in particular a laser. The workpiece is preferably in the form of a metal sheet.

The device can have a second light source, which is opposite the first light source and can be arranged at an angle of more than 0° and less than 45° to the cutting edge.

The second light source can be arranged at a minimum angle of more than 1°, in particular more than 3°, preferably more than 5°, particularly preferably more than 10°. The second light source can be arranged at a maximum angle of less than 30°, in particular less than 20°, to the cutting edge. The angle of the second light source to the cutting edge is preferably chosen depending on the material.

The second light source is preferably arranged mirrored about the workpiece plane with respect to the first light source.

• • Eine Frontallichtquelle, durch die die Schnittkante frontal beleuchtbar ist;
• • eine weitere Frontallichtquelle, durch die die Schnittkante frontal beleuchtbar ist;
• • eine Winkellichtquelle in der Werkstückebene, durch die die Schnittkante in einem Winkel zwischen 30° und 60° beleuchtbar ist;
• • eine der Winkellichtquelle gegenüberliegende weitere Winkellichtquelle in der Werkstückebene, durch die die Schnittkante in einem Winkel zwischen 30° und 60° beleuchtbar ist;
• • eine Seitenlichtquelle in der Werkstückebene, durch die die Schnittkante in einem Winkel von mehr als 0° und weniger als 45° beleuchtbar ist;
• • eine der Seitenlichtquelle gegenüberliegende weitere Seitenlichtquelle in der Werkstückebene, durch die die Schnittkante in einem Winkel von mehr als 0° und weniger als 45° beleuchtbar ist.

The device may include one or more of the following light sources:

• • A frontal light source, through which the cutting edge can be frontally illuminated;
• • another frontal light source, through which the cut edge can be frontally illuminated;
• • an angled light source in the workpiece plane, through which the cutting edge can be illuminated at an angle of between 30° and 60°;
• • a further angled light source opposite the angled light source in the workpiece plane, through which the cut edge can be illuminated at an angle of between 30° and 60°;
• • a side light source in the plane of the workpiece, through which the cut edge can be illuminated at an angle of more than 0° and less than 45°;
• • another side light source opposite the side light source in the workpiece plane, through which the cutting edge can be illuminated at an angle of more than 0° and less than 45°.

The side light source and/or the further side light source can be arranged to illuminate the cut edge at an angle of more than 1° and less than 30°, in particular at an angle of more than 2° and less than 20°.

The front light source and the further front light source are preferably designed to illuminate the cut edge in parallel. The angled light source and the further angled light source are preferably arranged mirrored about a plane of symmetry running perpendicular to the plane of the workpiece. The side light source and the further side light source are preferably arranged mirrored to a plane of symmetry running perpendicular to the plane of the workpiece.

The light sources can be of the same design. The light source(s) is/are preferably in the form of light-emitting diodes (LEDs). The light source(s) can particularly preferably be embodied in the form of high-power LEDs, in particular in the form of warm-white LEDs.

More preferably, the light sources are ±40%, in particular ±25%, preferably ±20%, particularly preferably ±15%, equidistant from the center of the cutting edge. The light sources can be arranged hemispherically around the center of the cutting edge.

The light sources can be controlled via a DigIO card or a DigIO board of the device.

The device can have a smartphone, with the camera being designed in the form of a smartphone camera.

The cutting edge image can be transmitted from the smartphone to a computer via a suitable interface, in particular via an Android Debugging Bridge (ADB).

The device can have a computer with a trained neural network, in which case the cut edge image can be supplied to the neural network in order to determine and output the roughness, the cut edge bevel and/or the burr formation.

A convolutional neural network, in particular one of the following neural networks mentioned above, is preferably used as the neural network: AlexNet, MobileNet, Xception.

The computer can have an algorithm which is designed to split the intersection image before supplying the intersection image to the neural network and to combine it into a square intersection image.

Further advantages of the invention result from the description and the drawing. Likewise, the above and still know According to the invention, the features described can each be used individually or collectively in any combination. The embodiments shown and described are not to be understood as an exhaustive list, but rather have an exemplary character for the description of the invention.

character list

• 1a shows schematically a device according to the invention with several light sources and a camera for creating a meaningful cut edge image in plan view.
• 1b shows the device schematically 1a in side view.
• 2 shows an isometric view of the device according to the invention.
• 3 shows a circuit diagram of the device for driving the light sources and the camera.
• 4a-4n show cutting edge images that were recorded with different light sources switched on and off.

the 1a and 1b show a device 10 for creating at least one cutting edge image of a cutting edge 12 of a workpiece 14. 1a shows the device 10 in a plan view, 1b shows the device 10 in a side view. the 1a and 1b are described together below.

The cut edge 12 is produced in a method step A) with a beam, in particular a laser beam, the cutting direction of which is indicated by an arrow 16 . The cutting direction is understood to be the direction of the axis of the beam, here the optical axis of the laser beam. The workpiece 14 is preferably cut perpendicularly to the workpiece plane 18 . The workpiece plane 18 is understood to mean a plane that extends infinitely far and runs through the center of the workpiece 14 .

At least one cutting edge image is created with a camera 20 in method step B). In the present case, the camera 20 is part of a smartphone 22. Several cutting edge images can be created with different lighting.

A first light source 24 is provided to illuminate the cutting edge 12 . In addition to this, a second light source 26 lying opposite the first light source 24 can be provided. In the exemplary embodiment shown, the first light source 24 illuminates the cutting edge 12 almost parallel to the cutting direction 16 and the second light source 26 illuminates the cutting edge 12 almost antiparallel to the cutting direction 16. However, it is also possible for the first light source 24 to illuminate the cutting edge 12 almost antiparallel or the second Light source 26 illuminates the cut edge 12 almost in parallel.

The first light source 24 and the second light source 26 are arranged at a significant distance from the workpiece plane 18 and illuminate the cutting edge 12 at an acute angle w1. As a result, details of the cut edge 12 are particularly clearly visible.

• • Eine Frontallichtquelle 28, die die Schnittkante 12 frontal, d.h. in Richtung der Werkstückebene 18, beleuchtet;
• • eine weitere Frontallichtquelle 30, die die Schnittkante 12 frontal beleuchtet;
• • eine Winkellichtquelle 32, die die Schnittkante 12 in der Werkstückebene 18 in einem Winkel w2 von ca. 45° zur optischen Achse 34 der Kamera 20 beleuchtet;
• • eine weitere Winkellichtquelle 36, die die Schnittkante 12 in der Werkstückebene 18 im Winkel w2 von ca. 45° zur optischen Achse 34 der Kamera 20 beleuchtet;
• • eine Seitenlichtquelle 38, die die Schnittkante 12 in der Werkstückebene 18 in einem spitzen Winkel w3 zur Längsachse 40 der Schnittkante 12 beleuchtet;
• • eine weitere Seitenlichtquelle 42, die die Schnittkante 12 in der Werkstückebene 18 im Winkel w3 zur Längsachse 40 der Schnittkante 12 beleuchtet.

One or more of the following light sources can be provided to illuminate the cutting edge 12:

• • A frontal light source 28, which frontally illuminates the cut edge 12, ie in the direction of the workpiece plane 18;
• • another frontal light source 30, which frontally illuminates the cutting edge 12;
• • an angled light source 32, which illuminates the cut edge 12 in the workpiece plane 18 at an angle w2 of approximately 45° to the optical axis 34 of the camera 20;
• • a further angled light source 36, which illuminates the cutting edge 12 in the workpiece plane 18 at an angle w2 of approximately 45° to the optical axis 34 of the camera 20;
• • a side light source 38, which illuminates the cutting edge 12 in the workpiece plane 18 at an acute angle w3 to the longitudinal axis 40 of the cutting edge 12;
• • Another side light source 42 that illuminates the cut edge 12 in the workpiece plane 18 at an angle w3 to the longitudinal axis 40 of the cut edge 12 .

The longitudinal axis 40 of the cutting edge 12 is understood to be an infinitely extending axis running through the center of the cutting edge 12 .

The angles w1 and w3 are preferably equal.

How from the 1a and 1b As can be seen, the light sources 24, 26, 28, 30, 32, 36, 38, 42 have essentially the same distance from the center of the cutting edge 12, ie the crossing point between the optical axis 34 and the longitudinal axis 40. The light sources 24 , 26 , 28 , 30 , 32 , 36 , 38 , 42 are arranged essentially hemispherically towards the center of the cutting edge 12 .

2 shows another view of the device 10. From 2 it can be seen that the device 10 has a workpiece holder 44 for receiving, esp special edition, the workpiece 14 with the cutting edge 12 has.

The device 10 has a smartphone holder 46 for the smartphone 22 . Furthermore, the device 10 has a light source holder 48 for the light sources 24, 26, 28, 30, 32, 36, 38, 42 (see 1a , 1b ; in 2 only the side light source 38 is clearly visible). The smartphone holder 46 and/or the light source holder 48 can have at least one profile bar 50, in particular a plurality of profile bars (not provided with reference numbers for reasons of clarity), in particular in the form of an aluminum profile bar or in the form of aluminum profile bars, in order to allow flexible adjustment of the To allow device 10. The device 10 can furthermore have a perforated plate 52 for the flexible mounting of the device 10 .

3 shows a circuit diagram of the device 10. The light sources 24, 26, 28, 30, 32, 36, 38, 42 (see 1a , 1b) shown schematically in the form of circles. A computer 54 is provided for controlling the light sources 24 , 26 , 28 , 30 , 32 , 36 , 38 , 42 and the smartphone 22 or the camera 20 . The light sources 24, 26, 28, 30, 32, 36, 38, 42 can be switched on and off via a DigIO board or a DigIO card 56.

The computer 54 can have a neural network 58 . The neural network 58 can be trained to analyze, in particular in a method step D), the at least one recorded cutting edge image, in particular a plurality of recorded cutting edge images, and to identify features of the cutting edge 12 (see 1a , 1b and 2 ) to identify. The neural network 58 is preferably trained to detect the roughness, cut edge bevel and/or burr formation of the cut edge 12 (see 1a , 1b and 2 ) to determine.

The neural network 58 can be part of an algorithm 60 . The algorithm 60 can be designed to divide the cutting edge image or images by the neural network 58 in particular in a method step C), before the analysis of the cutting edge image or images, and to output it in square form. As a result, the cutting edge image or images can be better processed by the neural network 58 and the information content of the cutting edge image or images is increased.

the 4a until 4n show the same cutting edge 12 (see 1a , 1b and 2 ) at different illuminations by the light sources 24, 26, 28, 30, 32, 36, 38, 42 (see 1a , 1b) .

• • 4a: Alle Lichtquellen 24, 26, 28, 30, 32, 36, 38, 42 aus;
• • 4b: Frontallichtquelle 28 und weitere Frontallichtquelle 30 an, alle weiteren Lichtquellen 24, 26, 32, 36, 38, 42 aus;
• • 4c: Winkellichtquelle 32 und weitere Winkellichtquelle 36 an, alle weiteren Lichtquellen 24, 26, 28, 30, 38, 42 aus;
• • 4d: Frontallichtquelle 28, weitere Frontallichtquelle 30, Winkellichtquelle 32 und weitere Winkellichtquelle 36 an, alle weiteren Lichtquellen 24, 26, 38, 42 aus;
• • 4e: Seitenlichtquelle 38, weitere Seitenlichtquelle 42, erste Lichtquelle 24 und zweite Lichtquelle 26 an; alle weiteren Lichtquellen 28, 30, 32, 36 aus;
• • 4f: Seitenlichtquelle 38 an; alle weiteren Lichtquellen 24, 26, 28, 30, 32, 36, 42 aus;
• • 4g: Weitere Seitenlichtquelle 42 an; alle weiteren Lichtquellen 24, 26, 28, 30, 32, 36, 38 aus;
• • 4h: Erste Lichtquelle 24 an; alle weiteren Lichtquellen 26, 28, 30, 32, 36, 38, 42 aus;
• • 4i: Zweite Lichtquelle 26 an; alle weiteren Lichtquellen 24, 28, 30, 32, 36, 38, 42 aus;
• • 4j: Winkellichtquelle 32 an; alle weiteren Lichtquellen 24, 26, 28, 30, 36, 38, 42 aus;
• • 4k: Weitere Winkellichtquelle 36 an; alle weiteren Lichtquellen 24, 26, 28, 30, 32, 38, 42 aus;
• • 41: Seitenlichtquelle 38 und weitere Seitenlichtquelle 42 an; alle weiteren Lichtquellen 24, 26, 28, 30, 32, 36 aus;
• • 4m: erste Lichtquelle 24 und zweite Lichtquelle 26 an; alle weiteren Lichtquellen 28, 30, 32, 36, 38, 42 aus;
• • 4n: Frontallichtquelle 28, weitere Frontallichtquelle 30 und erste Lichtquelle 24 an; alle weiteren Lichtquellen 26, 32, 36, 38, 42 aus.

The light sources are switched on and off as follows:

• • 4a : All light sources 24, 26, 28, 30, 32, 36, 38, 42 off;
• • 4b : frontal light source 28 and further frontal light source 30 on, all further light sources 24, 26, 32, 36, 38, 42 off;
• • 4c : angled light source 32 and further angled light source 36 on, all further light sources 24, 26, 28, 30, 38, 42 off;
• • 4d : frontal light source 28, further frontal light source 30, angled light source 32 and further angled light source 36 on, all further light sources 24, 26, 38, 42 off;
• • 4e : side light source 38, further side light source 42, first light source 24 and second light source 26 on; all other light sources 28, 30, 32, 36 off;
• • 4f : side light source 38 on; all other light sources 24, 26, 28, 30, 32, 36, 42 off;
• • 4g : Another side light source 42 on; all other light sources 24, 26, 28, 30, 32, 36, 38 off;
• • 4 hours : First light source 24 on; all other light sources 26, 28, 30, 32, 36, 38, 42 off;
• • 4i : Second light source 26 on; all other light sources 24, 28, 30, 32, 36, 38, 42 off;
• • 4y : angle light source 32 on; all other light sources 24, 26, 28, 30, 36, 38, 42 off;
• • 4k : Further angle light source 36 on; all other light sources 24, 26, 28, 30, 32, 38, 42 off;
• • 41 : side light source 38 and further side light source 42 on; all other light sources 24, 26, 28, 30, 32, 36 off;
• • 4m : first light source 24 and second light source 26 on; all other light sources 28, 30, 32, 36, 38, 42 off;
• • 4n : front light source 28, further front light source 30 and first light source 24 on; all other light sources 26, 32, 36, 38, 42 off.

It has been shown that the neural network 58 (see 3 ) from the cutting edge image according to 4a (all light sources 24, 26, 28, 30, 32, 36, 38, 42 off, only backlight on) is best suited to avoid burring of the cut edge 12 (see 1a , 1b and 2 ) to investigate.

Furthermore, it has been shown that the lighting according to 4 hours , 4i and 4m (First light source 24 and/or second light source 26 on, all further light sources 28, 30, 32, 36, 38, 42) for the neural network 58 (see 3 ) is best suited to reduce the roughness and the bevel of the cutting edge 12 (see 1a , 1b and 2 ) to investigate.

In general, it has been shown that determining the correct parameters for the cutting edge 12 (see 1a , 1b and 2 ) by means of the neural network 58 (see 3 ) can be optimized by different illuminations.

Taking all the figures of the drawing together, the invention relates to an apparatus 10 for analyzing a cut edge 12 of a workpiece 14. The workpiece 14 can be held in a workpiece holder 44 in order to illuminate the cut edge 12 with a first light source 24 at an acute angle w1 . The illumination by the first light source 24 is preferably parallel or anti-parallel to the cutting direction 16 of the cutting edge 12 up to a few degrees. In other words, the illumination by the first light source 24 is at an acute angle w1 to a plane that is perpendicular to the workpiece plane 18 in Direction of the longitudinal axis 40 of the cutting edge 12 extends. The first light source 24 is preferably arranged offset parallel to the workpiece plane 18 . The device 10 has a camera 20 whose optical axis 34 preferably extends in the workpiece plane 18 . A computer 54 can have an algorithm 60, in particular with a neural network 58, in order to analyze cutting edge images created with the camera 20. The invention also relates to a method for analyzing the cut edge 12, in particular with such a device 10.

Reference List

10

contraption

12

cutting edge

14

workpiece

16

Cutting direction of a laser beam

18

workpiece level

20

camera

22

smartphone

24

first light source

26

second light source

28

frontal light source

30

additional frontal light source

32

angle light source

34

optical axis of the camera 20

36

another angle light source

38

side light source

40

Long axis of the cutting edge 12

42

further side light source

44

workpiece holder

46

smartphone holder

48

light source holder

50

profile bar

52

perforated plate

54

calculator

56

DigIO card

58

neural network

60

algorithm

w1

Angle of the first light source 24 and the second light source 26 to the cutting edge 12

w2

Angle of the angle light sources 32, 34 to the optical axis 34 of the camera 20

w3

Angle of the side light sources 38, 42 to the longitudinal axis 40 of the cutting edge 12

QUOTES INCLUDED IN DESCRIPTION

This list of the documents cited by the applicant was generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Patent Literature Cited

• DE 102008024806 A1 [0003]
• DE 2941815 A1 [0004]
• DE 102004050428 A1 [0005]
• DE 19758214 A1 [0006]
• DE 102017211680 A1 [0007]
• DE 102013107639 A1 [0008]

Claims (15)

Method for analyzing a cut edge (12) of a workpiece (14) with the method step: B) illuminating the cut edge (12) with a first light source (24) and recording a cut edge image with a camera (20), characterized in that the first light source (24) is arranged at a distance perpendicular to the workpiece plane (18) and illuminates the cutting edge (12) at an angle (w1) of more than 0° and less than 45°. procedure after claim 1 , in which the following method step is carried out before method step B): A) Laser cutting of the workpiece (14) to create the cutting edge (12). procedure after claim 1 or 2 , in which the cutting edge (12) is illuminated by a second light source (26) when the cutting edge image is recorded, the second light source (26) lying opposite the first light source (24), being arranged at a distance perpendicular to the workpiece plane (18) and the cutting edge ( 12) illuminated at an angle (w1) greater than 0° and less than 45°. Method according to one of the preceding claims, in which before or after method step B) a cut edge image is recorded with the camera (20) with the light sources (24, 26, 28, 30, 32, 36, 38, 42) switched off. Method according to one of the preceding claims, in which the cut edge (12) is illuminated by one or more of the following light sources (28, 30, 32, 36, 38, 42) when the cut edge image is created: • A frontal light source (28) which illuminates the cutting edge (12) frontally, i.e. in the workpiece plane (18); • a further frontal light source (30) which frontally illuminates the cutting edge (12); • an angled light source (32) which illuminates the cutting edge (12) in the workpiece plane (18) at an angle (w2) of between 30° and 60°; • a further angle light source (36) opposite the angle light source (32) and illuminating the cutting edge (12) in the workpiece plane (18) at an angle (w2) of between 30° and 60°; • a side light source (38) which illuminates the cut edge (12) in the workpiece plane (18) at an angle (w3) of more than 0° and less than 45°; • a further side light source (42) opposite the side light source (38), which illuminates the cutting edge (12) in the workpiece plane (18) at an angle (w3) of more than 0° and less than 45°. procedure after claim 5 combined with claim 4 , in which cut edge images are recorded with the camera (20), the cut edge (12) being illuminated in any order as follows when the respective cut edge images are recorded: All light sources (24, 26, 28, 30, 32, 36, 38, 42) off; • Frontal light source (28) and further frontal light source (30) on, all further light sources (24, 26, 32, 36, 38, 42) off; • angled light source (32) and further angled light source (36) on, all further light sources (24, 26, 28, 30, 38, 42) off; • Frontal light source (28), additional frontal light source (30), angled light source (32) and additional angled light source (36) on, all additional light sources (24, 26, 38, 42) off; • side light source (38), further side light source (42), first light source (24) and second light source (26); all other light sources (28, 30, 32, 36) off; • side light source (38) on; all other light sources (24, 26, 28, 30, 32, 36, 42) off; • additional side light source (42); all other light sources (24, 26, 28, 30, 32, 36, 38) off; • first light source (24) on; all other light sources (26, 28, 30, 32, 36, 38, 42) off; • second light source (26) on; all other light sources (24, 28, 30, 32, 36, 38, 42) off; • Angle light source (32) on; all other light sources (24, 26, 28, 30, 36, 38, 42) off; • further angle light source (36); all other light sources (24, 26, 28, 30, 32, 38, 42) off; • side light source (38) and further side light source (42); all other light sources (24, 26, 28, 30, 32, 36) off; • first light source (24) and second light source (26); all other light sources (28, 30, 32, 36, 38, 42) off; • Front light source (28), further front light source (30) and first light source (24); all other light sources (26, 32, 36, 38, 42) off. Method according to one of the preceding claims, in which the cutting edge image is created with a camera (20) in the form of a smartphone camera. Method according to one of the preceding claims, including the method step D) Supplying the cut edge image to a trained neural network (58), the neural network (58) using the cut edge image to determine and output the roughness, the cut edge inclination and/or the burr formation. procedure after claim 8 , in which the following process step is carried out before process step D): C) Splitting the crop edge image and merging it into a square crop edge image. Device (10) for analyzing a cutting edge (12), in particular with a method according to one of the preceding claims, the device (10) having the following: a) a workpiece holder (44) for receiving a workpiece (14) with a cutting edge (12 ); b) a camera (20) for capturing a cut edge image; characterized in that the device (10) comprises: c) a first light source (24), the first light source (24) being spaced perpendicularly to the workpiece plane (18) and for illuminating the cutting edge (12) at an angle (w1) of more than 0° and less than 45° can be arranged. device after claim 10 In which the device (10) has a second light source (26) which is opposite the first light source (24) and can be arranged at an angle (w1) of more than 0° and less than 45° to the cutting edge (12). device after claim 10 or 11 , in which the device (10) has one or more of the following light sources (28, 30, 32, 36, 38, 42): • A frontal light source (28) through which the cutting edge (12) frontally, ie in the direction of the workpiece plane (18) can be illuminated; • a further frontal light source (30) through which the cut edge (12) can be illuminated frontally, ie in the direction of the workpiece plane (18); • an angled light source (32) in the workpiece plane (18), through which the cutting edge (12) can be illuminated at an angle (w2) of between 30° and 60°; • a further angled light source (36) opposite the angled light source (32) in the workpiece plane (18), through which the cutting edge (12) can be illuminated at an angle (w2) of between 30° and 60°; • a side light source (38) in the workpiece plane (18), through which the cutting edge (12) can be illuminated at an angle (w3) of more than 0° and less than 45°; • a further side light source (42) opposite the side light source (38) in the workpiece plane (18), through which the cutting edge (12) can be illuminated at an angle (w3) of more than 0° and less than 45°. Device according to one of Claims 10 until 12 , In which the device (10) has a smartphone and the camera (20) is designed in the form of a smartphone camera. Device according to one of Claims 10 until 13 , in which the device (10) has a computer (54) with a trained neural network (58), the cut edge image being feedable to the neural network (58) in order to determine and output the roughness, the cut edge bevel and/or the formation of burrs . device after Claim 14 , in which the computer (54) has an algorithm (60) which is designed to split the cutting edge image before supplying the cutting edge image to the neural network (58) and to combine it to form a square cutting edge image.

Images