Method and laser cutting machine for the laser cutting of workpiece parts from a workpiece

Abstract

The invention relates to a method (100) for the laser cutting of workpiece parts (44) from at least one workpiece (40) using a laser beam (1) of a laser cutting machine (10), wherein the method (100) has the following steps (102, 108, 110): - ascertaining at least one material quality parameter (2) of the material quality of the at least one workpiece (40), - determining at least one laser cutting parameter (2) for the laser cutting of the workpiece parts (44), said at least one laser cutting parameter (5) being determined on the basis of the at least one ascertained material quality parameter (2), and - laser cutting the workpiece parts (44) from the at least one workpiece (40) using the laser beam (1) of the laser cutting machine (10), the at least one determined laser cutting parameter (5) being used for the laser cutting process.

Description

[0001] Title: Method and laser cutting machine for

[0002] Laser cutting of workpiece parts from a

[0003] workpiece

[0004] Description

[0005] The invention relates to a method and a laser cutting machine for laser cutting workpiece parts from at least one workpiece by means of a laser beam.

[0006] It is known that the quality of a laser-cut workpiece depends significantly on the quality of the raw material used and on the cross-sectional image produced in the laser cutting process. This cross-sectional image in turn depends on the material quality, in particular on the choice of material and the condition of the workpiece used. This condition can also change due to the type and duration of storage of the workpieces, for example due to corrosion. It has been found that as a result of these quality fluctuations in the workpieces used, a cross-sectional image is typically produced which in turn can have certain quality deficiencies, in particular with regard to the length of the burr, the roughness of the surface, the colour of the cut (tarnish) or uncontrolled burn-out (in the case of flame cutting).

[0007] The object of the invention is to at least partially reduce the above-mentioned quality deficiencies of workpiece parts cut in a laser cutting process of a laser cutting machine.

[0008] The object is achieved by a method according to claim 1. Accordingly, a method is proposed for laser cutting workpiece parts from at least one workpiece by means of a laser beam of a laser cutting machine, the method comprising the following steps:

[0009] - Determining at least one material quality parameter of a material quality of the at least one workpiece,

[0010] - Determining at least one laser cutting parameter for laser cutting the workpiece parts, wherein the at least one laser cutting parameter is determined as a function of the determined at least one material quality parameter, and

[0011] - laser cutting the workpiece parts from the at least one workpiece by means of the laser beam of the laser cutting machine, wherein the at least one specific laser cutting parameter is used for the laser cutting process.

[0012] According to the invention, a material quality of the workpiece or workpieces intended for laser processing is first determined, whereby one or more

[0013] Material quality parameters are determined which can be used to specify the material quality in order to ensure comparability between different material qualities. One or more laser cutting parameters are then determined for the laser cutting process depending on the material quality parameter(s). Of course, the laser cutting parameters do not have to be determined solely on the basis of at least one material quality parameter, but can also be dependent on other influencing factors, such as the working range of the laser cutting machine. What is crucial is that the material quality parameter(s) are taken into account when determining the laser cutting parameter. The at least one previously determined laser cutting parameter is then used for the laser cutting process in order to carry out a laser cutting process that is adapted to the material quality.Consequently, the laser cutting process is adapted to the quality of the material of the workpiece(s) used by the method according to the invention to avoid quality deficiencies in the manufactured workpiece parts. The laser cutting process itself can then proceed according to a nesting plan that specifies the geometry of the workpiece parts to be cut and can specify their positioning on the workpiece.

[0014] Various applications can be used to determine the laser cutting parameters as a function of the material quality parameters so that a high quality or at least a required quality of the workpiece parts is achieved. For example, a database can be used to determine at least one laser cutting parameter, in which database optimal laser cutting parameters are specified as a function of material quality parameters (and possibly the further dependencies for determining the laser cutting parameters mentioned later). Such a database can, for example, be based on empirical values ​​and / or tests. However, it can also be based on a simulation. A simulation of different laser cutting parameters can also be carried out for specific material quality parameters, in particular combinations of material quality parameters, and depending on a simulation result with regard toOne or more laser cutting parameters, in particular a set of laser cutting parameters, are determined based on the quality of the cut-out workpiece parts. Additionally or alternatively, artificial intelligence, in particular machine learning, can be used, for example, to determine the at least one laser cutting parameter.

[0015] In the present case, a workpiece is understood to mean, in particular, a workpiece panel or workpiece plate which has its greatest extent in a horizontal plane and is designed with a thickness in the vertical plane orthogonal thereto. A workpiece can, in particular, be a workpiece sheet. Such a workpiece can also be referred to as a machined workpiece if workpiece parts are incorporated therein which are connected to the workpiece by a predetermined breaking point. Such a predetermined breaking point can, in particular, be in the form of a web between the workpiece parts and the workpiece or a remaining skeleton of the workpiece.The predetermined breaking point ensures, on the one hand, that the workpiece with all workpiece parts can be safely removed from the laser cutting machine and, on the other hand, that the workpiece parts can be easily detached from the workpiece and thus removed from the laser cutting machine.

[0016] The laser cutting process can be at least partially automated, in particular fully automated. The laser cutting machine used can be designed in particular as a flatbed machine tool, in particular a 2D laser flatbed machine. The flatbed machine tool cuts the workpiece parts, which are defined in their shape by a nesting plan of the

[0017] Flatbed machine tool can be specified, separated from the rest of the workpiece by means of laser cutting. The workpiece parts are therefore cut out of the workpiece in particular by means of a laser beam. However, the predetermined breaking point can remain, which connects each workpiece part to the rest of the workpiece, which is also referred to herein as the residual skeleton and may represent recyclable waste. Several predetermined breaking points can also remain between each workpiece part and the workpiece. The workpiece machined in this way can now be fed to the so-called sorting in or on the laser cutting machine, since the workpiece parts are still attached to the residual skeleton of the workpiece by means of the predetermined breaking point. The breaking of the predetermined breaking point or the detachment of the workpiece parts from the residual skeleton of the workpiece can be done manually, semi-automatically or fully automatically. A tool, for example a vibrator, a so-calledA vibrating hammer or a drill can be used. A vibrator or vibrating hammer uses vibration to create periodically repeated vibrations or impacts on the workpiece, so that the workpiece parts are released from the workpiece. A drill can break open the predetermined breaking point by drilling at the predetermined breaking point or at a drilling point provided next to the workpiece part, in particular a so-called microjoint.

[0018] It can be provided that the method further comprises the step of specifying a target workpiece part quality, wherein the determination of the at least one laser cutting parameter is carried out in such a way that the predetermined target workpiece part quality is achieved in the laser cutting process.

[0019] In other words, it can be provided that a required workpiece part quality is specified in the process. The target workpiece part quality can in turn be quantified using workpiece part quality parameters in order to ensure comparability and evaluation. The laser cutting parameter(s) can then be determined in such a way that, depending on the material quality parameters, it can be ensured, in particular with a predefined expected value, that (at least) the required workpiece part quality is achieved during the laser cutting process.This makes the process particularly efficient because the maximum achievable workpiece quality, which may not even be necessary for the subsequent processing or use of the workpiece parts, is not offset by other disadvantages, such as slow laser cutting, high wear or high energy and cutting gas consumption, which can be the case with a laser cutting process with maximum quality requirements.

[0020] It can also be provided that at least one machine state parameter of a machine state of the laser cutting machine is determined and that the at least one laser cutting parameter is also determined as a function of the determined at least one machine state parameter. As a result, a further parameter which has been determined as being relevant for the workpiece part quality can be included in the method according to the invention in order to be able to guarantee the production of workpiece parts of high, in particular required, workpiece part quality. In this case, it can be provided that the at least one machine state parameter indicates at least one maintenance state and / or an operating state of the laser cutting machine. The maintenance state and the operating state provide information about how reliably or error-free the laser cutting machine is expected to operate.Depending on this, countermeasures can be taken by determining the laser cutting parameter(s). For example, high tolerances of the laser cutting machine due to insufficient or long-ago maintenance can be counteracted by using low laser cutting speeds and low laser cutting intensities as possible laser cutting parameters to compensate for the tolerances. However, for an optimally or recently maintained laser cutting machine, the laser cutting parameters can be determined more closely depending on the material quality parameter(s), because a negative influence of the machine's condition can be largely ruled out. The same applies to the operating condition.This can, for example, indicate how long the laser cutting machine has been in operation overall or in an ongoing production cycle, whether it has already warmed up or whether a cold start is required for the laser cutting process, whether there is any contamination, e.g. of a protective glass on the laser cutting machine, or defects and / or what the condition of individual components of the laser cutting machine is, e.g. the nozzles. Different modules or units of the laser cutting machine can be used to determine the machine condition parameters. For example, a maintenance documentation module, a control unit, a sensor and / or a camera can be used to determine the maintenance status and / or the operating status.One possible example of a sensor is a scattered light sensor, which can detect a thermal shift in the laser beam using scattered light analysis, for example due to contamination of the protective glass. Based on the degree of contamination determined on the basis of the scattered light analysis, a machine status parameter can be determined accordingly and used to determine at least one laser cutting parameter. A focus position control, which is dependent on laser power and beam-on time, can also be used to calculate the thermal shift. For example, a low laser cutting speed can then be selected as the laser cutting parameter in order to compensate for the contamination in relation to the produced workpiece quality until it is removed.

[0021] Furthermore, it can be provided that the at least one material quality parameter is determined on the basis of manufacturer-side workpiece data and / or measurement data from a measurement of the at least one workpiece by means of at least one sensor and / or at least one camera. It is particularly advantageous if both manufacturer-side workpiece data and measurement data are used in order to be able to determine as many different material quality parameters as possible and with as much detail as possible, which advantageously creates a large amount of data for determining the laser cutting parameter(s). In this case, the manufacturer-side workpiece data can sometimes provide different material quality parameters than the measurement data. It is also possible to verify and check the manufacturer-side workpiece data using the measurement data.This allows for workpiece mix-ups, incorrect information in the workpiece data, or expired information, such as rust-free workpieces after extended storage or transport defects, to be detected and taken into account in the process. This ensures that the material quality is correctly determined and that the required target workpiece quality can be guaranteed through the appropriate selection of the laser cutting parameter(s).

[0022] It can also be provided that the at least one material quality parameter indicates at least one of a material composition, a grain size of the material, a surface quality, and / or a material condition. It has been shown that the aforementioned material quality parameters are highly significant for the subsequent workpiece quality, depending on the specific laser cutting parameters.

[0023] Furthermore, it can be provided that the at least one laser cutting parameter specifies at least one of a laser cutting power, a laser cutting feed, a focus position, a focus diameter, a nozzle position, and / or a laser cutting gas pressure. It has been shown that the above laser cutting parameters are particularly suitable adjustment screws in the laser cutting process for achieving a required target workpiece quality on the one hand, and for avoiding disadvantages during the laser cutting process on the other.

[0024] In particular, it may be provided that the method further comprises the following further steps:

[0025] Generating measurement data relating to the workpiece parts, the at least one workpiece and / or the laser cutting process by means of at least one sensor and / or at least one camera,

[0026] - Analyzing the measurement data to determine the actual quality of the workpiece parts, and

[0027] - Adjusting the at least one laser cutting parameter on the basis of the analyzed actual workpiece part quality, in particular in comparison to a predetermined target workpiece part quality.

[0028] By measuring the workpiece parts and / or the at least one workpiece and / or monitoring the laser cutting process, a check of the achieved workpiece part quality is provided during or between the laser cutting process, wherein countermeasures are also taken during the laser cutting process by adjusting the laser cutting parameter(s), in particular if the workpiece part quality determined by analysis of the measured data is below a predetermined target workpiece part quality. For example, to generate the measured data, a light section can be taken to measure the burr height and / or an incident light image of the cutting edge can be taken to determine the scoring and the tarnish colors. The analysis of the measured data to determine the actual workpiece part quality can also be supported by artificial intelligence, in particular machine learning.In this way, the analysis of sensor and / or camera images, for example, can become increasingly better in order to be able to determine the actual workpiece quality ever more quickly and precisely. It is also possible to adapt the laser cutting parameter(s) if the workpiece quality turns out to be (significantly) higher than specified, for example in order to speed up the laser cutting process. As already indicated, high quality also entails disadvantages with regard to process control, in particular with regard to the process duration and the costs associated with laser cutting. If a certain high quality is not expected, it can be ensured that the workpiece part quality produced essentially exactly as desired. The laser cutting parameter(s) determined at the outset therefore represent merely an initial configuration for the start of the laser cutting process or the initial laser cutting process.This initial configuration with one or more laser cutting parameters can be adapted as described above to a processing configuration that is determined for the further laser cutting process to achieve a specified target workpiece part quality.

[0029] In this case, it can be provided that the steps of generation, in particular with measuring and / or monitoring, analysis and adjustment are repeated, in particular until the actual workpiece part quality corresponds at least to the specified workpiece part quality. In this way, the laser cutting parameters can be adjusted step by step and continuously until the required target workpiece part quality is achieved. Of course, in addition, measurement data can also be generated by measuring and / or monitoring and the measurement data can be analyzed to determine the actual workpiece part quality in order to ensure that the achieved actual workpiece part quality can be maintained in the further laser cutting process.

[0030] It can also be provided that the at least one sensor and / or the at least one camera is connected to at least one of a slag expulsion unit for detecting a spray jet during laser cutting, a spark detection unit for detecting a spark size and / or spark brightness during

[0031] Laser cutting, a line spectroscopy sensor for detecting spectral lines during laser cutting and a hyperspectral camera for detecting a temperature profile during laser cutting. The aforementioned detectors have proven to be particularly advantageous because they allow the actual workpiece quality to be determined precisely. They can also be used to advantageously monitor the laser cutting process. For example, the sparks when cutting into the workpiece can be evaluated, which allows the number and size of the sparks to be determined. The viscosity of the melt or the appearance of the spray jet can also be determined to analyse the melt expulsion and thus the actual workpiece quality. In addition to the advantageous evaluation of the line spectrum, the use of a hyperspectral camera, which offers the option of measuring in a larger wavelength range, e.g.a heat imprint, the slag expulsion can be detected and thereby the cutting quality and the workpiece part quality.

[0032] In particular, it can be provided that the at least one sensor and / or the at least one camera are a multi-detection system with at least two sensors and / or cameras. Such a multi-detection system can improve the measurement data situation by increasing the available data volume. Monitoring is also more reliable in the event that a detection unit fails or does not provide any usable measurement data. The increased amount of measurement data enables a more reliable and precise analysis of the measurement data to determine the actual workpiece part quality.

[0033] The object mentioned at the outset is further achieved by a laser cutting machine according to claim 12. The laser cutting machine is designed for laser cutting workpiece parts from at least one workpiece by means of a laser beam from a laser cutting head of the laser cutting machine, wherein the laser cutting machine comprises:

[0034] - a determination module for determining at least one material quality parameter of a material quality of the at least one workpiece,

[0035] - a determination module for determining at least one laser cutting parameter for laser cutting the workpiece parts, wherein the at least one laser cutting parameter is determined as a function of the at least one determined material quality parameter, and

[0036] - a control module for controlling the laser cutting of the workpiece parts from the at least one workpiece by means of the laser beam from the laser cutting head using the at least one specific laser cutting parameter.

[0037] In this case, features described herein with reference to the method apply equally to the laser cutting machine, and vice versa. Thus, a laser cutting machine according to the invention offers the same advantages as those explained in detail with reference to the method according to the invention. In particular, the laser cutting machine can be configured or designed to carry out the method according to the invention.

[0038] The modules of the laser cutting machine can, for example, each be implemented by a separate computer program code or by a common computer program code, by separate or common functional units of a computer and / or control units and / or other units. For example, the determination module can be designed as a read-in unit, such as a read-in program code, a memory of a computer and / or a sensor and / or a camera of the laser cutting machine. It is also possible for individual modules to be partially or completely implemented in a common module, for example the determination module and the determination module. For example, the modules of the laser cutting machine can be implemented in a control device of the laser cutting machine.

[0039] It can be provided that the laser cutting machine further comprises a further determination module for determining a machine state parameter of a machine state of the laser cutting machine, and the determination module is configured to also determine the at least one laser cutting parameter as a function of the at least one determined machine state parameter. It can be provided that the further determination module is or comprises a machine documentation module, by means of which the machine state parameters are documented.

[0040] In particular, it can be provided that the laser cutting machine further comprises:

[0041] - at least one sensor and / or at least one camera for generating measurement data relating to the workpiece parts, the at least one workpiece and / or the laser cutting process,

[0042] - an analysis module for analyzing the measurement data to determine the actual workpiece quality of the workpiece parts, and

[0043] - an adaptation module for adapting the at least one laser cutting parameter on the basis of the determined actual workpiece part quality, in particular in comparison to a predetermined target workpiece part quality.

[0044] In addition to the modules mentioned above, the laser cutting machine can of course incorporate additional modules and components. These include, for example, the aforementioned database, artificial intelligence, and / or a simulation module for determining the laser cutting parameter(s), as well as a specification module for specifying the workpiece quality, etc.

[0045] Further details and advantageous embodiments of the invention can be found in the following description, on the basis of which embodiments of the invention are described and explained in more detail.

[0046] Shown are: Figure 1 a perspective view of a

[0047] Laser cutting machine according to an embodiment of the invention;

[0048] Figure 2 is a schematic view of a

[0049] Laser cutting device as part of the laser cutting machine of Fig. 1;

[0050] Figure 3 is a schematic view of the control device of the laser cutting device of Figure 2;

[0051] Figure 4 is a schematic view of a

[0052] Laser cutting process according to a first embodiment of the invention using the laser cutting machine of Fig. 1;

[0053] Figure 5 is a schematic view of a

[0054] Laser cutting process according to a second embodiment of the invention by means of the laser cutting machine of Fig. 1; and

[0055] Figure 6 is a schematic view of a

[0056] Laser cutting process according to a third embodiment of the invention using the laser cutting machine of Fig. 1.

[0057] In the following description and in the figures, the same reference symbols are used for identical or corresponding features.

[0058] Figure 1 shows a laser cutting machine 10 in the form of a laser cutting flatbed machine tool with a laser cutting device 20, in which a laser cutting process is carried out with a laser beam 1 (see Fig. 2). In particular, a focus of the laser beam 1 is guided by a control device 50 (see Fig. 2) of the laser cutting machine 10 along predetermined cutting contours 42 arranged in a cutting area over a plate-shaped workpiece 40, in particular a sheet metal extending essentially two-dimensionally, in order to cut out workpiece parts 44 with specific shapes predetermined according to a nesting plan. The nesting plan can be predetermined by a control plan for the control device 50.

[0059] The laser cutting machine 10 here also comprises, by way of example, a removal device 30. The removal device 30 is shown open here for the sake of clarity, but can alternatively be partially or completely enclosed, like the laser cutting device 20 in Fig. 1. By way of example, the removal device 30 here comprises a pallet changer 32. The pallet changer 32 is designed to position one or more pallets 38 during production. A workpiece 40 to be cut (as raw or starting material), in particular a workpiece panel, can be placed and stored on a pallet 38 and introduced into the housing of the laser cutting device 20 for the laser cutting process. After the cutting process has been completed, the pallet 38 can be removed, as shown in Fig.1, can be moved out of the laser cutting device 20 with a machined workpiece 40, so that workpiece parts 44 cut according to the control plan can be sorted from the remaining workpiece 40 and removed from the laser cutting machine 10. Figure 2 shows the laser cutting process in the laser cutting device 20. A laser cutting head 24, which is controlled by the control device 50 and emits the laser beam 1 onto the workpiece 40 to cut out the workpiece parts 44 from the workpiece 40, can be freely positioned in the cutting area, so that the laser beam 1 can be guided essentially along any desired two-dimensional cutting contours 42 over the workpiece 40 to be cut. In this case, a cutting contour 42 for the laser beam 1 is predetermined in each case on the basis of the nesting plan in the control device 50 in order to cut out the workpiece parts 44 from the workpiece 40.The nesting plan specifies the arrangement of the individual workpiece parts 44 in the workpiece 40, as can be seen in Fig. 1. In addition, the nesting plan can include the specification of piercing points and predetermined cuts for piercing the laser beam 1 and guiding the laser beam 1 along the cuts to the cutting contour 42 (not shown).

[0060] During laser cutting, the laser beam 1 heats the metal of the workpiece 40 along the predetermined cutting contours 42 until it melts. A cutting gas jet, in particular consisting of nitrogen and / or oxygen, can emerge from the laser cutting head 24 in the region of the laser beam 1 and force the molten material of the workpiece 40 downward and out of the gap that forms. The workpiece 40 is thus completely severed by the laser beam 1 during cutting.

[0061] To cut out a workpiece part 44, the laser beam 1 is moved along the predetermined cutting contours 42 of the respective workpiece 40. This begins at one of the previously mentioned piercing points, which lie outside the workpiece 40, and then approaches the contour of the workpiece 40, in particular in an arcuate cut.

[0062] In the illustrated embodiment, the pallet 38 has a workpiece support. The workpiece support has a plurality of support webs 34 that extend transversely, in particular perpendicularly, to the direction of insertion of the workpiece 40 into the laser cutting device 20 and are aligned parallel to one another. The support webs 34 form support areas 36 on which the workpiece 40 is placed or supported. The support areas 36 thus form a grid of areas that can influence the laser cutting process and the removal of the workpiece parts 44 cut out thereon.

[0063] Fig. 1 further shows a camera 22 of the laser cutting machine 10, which is arranged, for example, on the laser cutting device 20 or its housing. The camera 22 can be part of the detection module 51 of the control device 50 of the laser cutting machine or can be connected thereto. The camera 22 is directed here purely by way of example and for the sake of better illustration, towards the removal device 30 and can alternatively or additionally be directed towards the laser cutting device 20, in particular can be arranged within the housing of the laser cutting device 20. Furthermore, sensors can also be used alternatively or in addition to the camera 22.

[0064] Figure 3 shows, by way of example and schematically, the control device 50 of the laser cutting device 20 of the laser cutting machine 10 with its respective modules. In the present example, these are a determination module 51, a further determination module 52, a specification module 53, a determination module 54, an analysis module 55, an adaptation module 56, and a control module 57. Alternatively, fewer modules can also be used, as will become clear from the exemplary embodiments of the method 100 according to the invention explained below.

[0065] Figure 4 schematically shows a first embodiment of a method 100 for laser cutting workpiece parts 44 from at least one workpiece 40 by means of the laser beam 1 from the laser cutting head 24 of the laser cutting device 20 of the laser cutting machine 10 of Fig. 1.

[0066] In a first step 102 of the method 100, material quality parameters 2 of a material quality of a workpiece 40, from which workpiece parts 44 are to be cut out according to the predetermined nesting plan, are determined by means of the determination module 51. This can preferably be done using manufacturer-side workpiece data and measurement data from a measurement of the at least one workpiece 40 using a sensor and / or the camera 22, which send their measurement data to the determination module 51. The measurement data can be acquired when the workpiece 40 is located in the laser cutting machine 10, for example on the removal device 30 or in the laser cutting device 20. The determination module 51 determines the material quality parameters 2 on the basis of the measurement data and the manufacturer-side workpiece data.Different material quality parameters 2 determined in this way can be, for example, a material composition, a grain size of the material, a surface quality and / or a.

[0067] Specify the material condition. This

[0068] Material quality parameter 2 can be used to describe very precisely the material quality of the workpiece 40 from which the workpiece parts 44 are to be cut out of the workpiece 40 by the laser cutting machine 10 according to the nesting plan.

[0069] In parallel, before or after step 102, step 104 of method 100 takes place, in which the further determination module 52 determines machine status parameters 3, which can, for example, indicate a maintenance status and / or operating status of the laser cutting machine 10, in particular of the laser cutting device 20. The further determination module 52 can, for example, be or contain a machine documentation module, in particular for documenting the maintenance of the laser cutting machine 10, by which the machine status parameters 3 are documented.

[0070] The determined material quality parameters 2 and the machine condition parameters 3 are transmitted to the determination module 54, which, in a step 108 of the method 100, determines a plurality of laser cutting parameters 5, adapted to the previously determined material quality parameters 2 and machine condition parameters 3, for the laser cutting process of laser cutting the workpiece parts 44 from the workpiece 40. The different laser cutting parameters 5 determined in this way can, for example, specify a laser cutting power, a laser cutting feed, a focus position, a focus diameter, a nozzle position and a laser cutting gas pressure for execution by the control module 57 of the control device 50 of the laser cutting device 20. In step 110 of the method 100, the control module 57 uses the previously determined laser cutting parameters 5 to control the laser cutting process of the workpiece parts 44 from the workpiece 40 using the laser beam 1.This ensures that the laser cutting parameters 5 during laser cutting are adapted to the material quality of the workpiece 40 and the machine condition of the laser cutting machine 10, so that a high workpiece part quality of the manufactured workpiece parts 44 is achieved.

[0071] In a second exemplary embodiment of the method 100 according to FIG. 5, a specification module 53 of the control device 50 is also used. This specification module 53 specifies a required target workpiece part quality 4 in a step 106. This specified target workpiece part quality 4 is transmitted to the determination module 54. The determination module 54 also adapts the laser cutting parameters 5 to the required target workpiece part quality 4 in order to ensure that this is realized on the manufactured workpiece parts 44 with the determined material quality parameters 2 and the determined machine condition parameters 3.

[0072] A third embodiment of the method 100 is embodied by Fig. 6, which also uses the analysis module 55 and the adaptation module 56 of the control device 50. In this case, the method 100 according to the second embodiment of Fig. 5 with the steps 102, 104, 106, 108 and 110 is first run through. Unlike in Fig. 5, however, only an initial configuration of the determined laser cutting parameters 5 is determined for an initial laser cutting process, which is carried out in step 110. In a further step 112, this

[0073] Initial laser cutting process is monitored by the at least one camera 22 and / or the at least one sensor. In the process, measurement data 6 is recorded or generated. This measurement data 6 is transmitted to the analysis module 55, which analyzes it in order to determine an actual workpiece part quality 7 of the workpiece parts 44 cut out so far. Based on a comparison of the actual workpiece part quality 7 with the predetermined target workpiece part quality 4, it is determined whether the laser cutting parameters 5 of the initial configuration should be adjusted. If the actual workpiece part quality 7 does not yet correspond to or exceed the predetermined target workpiece part quality 4, this adjustment is carried out in step 116 of the method 100 by the adjustment module 56.The laser cutting parameters 5 adjusted in this way are fed back to step 110, i.e. to the laser cutting process, in order to continue an interrupted laser cutting process with the adjusted laser cutting parameters 5 or to continue an ongoing laser cutting process with the adjusted laser cutting parameters 5. It is also possible for steps 112, 114, 116 to be repeated until the actual workpiece part quality 7 corresponds at least to the predetermined target workpiece part quality 4. If this is the case, the laser cutting machine 10 has assumed its processing configuration with laser cutting parameters 5 that are optimally coordinated with regard to the material quality and the machine condition in order to produce an actual workpiece part quality 7 that essentially corresponds to the target workpiece part quality 4.

Claims

Patent claims Method (100) for laser cutting workpiece parts (44) from at least one workpiece (40) by means of a laser beam (1) of a laser cutting machine (10), wherein the method (100) comprises the following steps (102, 108, 110): - determining at least one material quality parameter (2) of a material quality of the at least one workpiece (40), - Determining at least one laser cutting parameter (2) for laser cutting the workpiece parts (44), wherein the at least one laser cutting parameter (5) is determined as a function of the at least one determined material quality parameter (2), and - Laser cutting the workpiece parts (44) from the at least one workpiece (40) by means of the laser beam (1) of the laser cutting machine (10), wherein the at least one specific laser cutting parameter (5) is used for the laser cutting process. Method (100) according to claim 1, wherein the method (100) further comprises the step (106) of specifying a target workpiece part quality (4), wherein the determination of the at least one laser cutting parameter (5) is carried out such that the specified target workpiece part quality (4) is achieved in the laser cutting process. Method (100) according to claim 1 or 2, wherein at least one machine state parameter (3) of a machine state of the laser cutting machine (10) is further determined. and the at least one laser cutting parameter (5) is also determined as a function of the at least one determined machine condition parameter (3). Method (100) according to claim 3, wherein the at least one machine condition parameter (3) indicates at least one maintenance condition and / or an operating condition of the laser cutting machine (10). Method (100) according to one of the preceding claims, wherein the at least one material quality parameter (2) is determined on the basis of manufacturer-side workpiece data and / or measurement data from a measurement of the at least one workpiece (40) is determined by means of at least one sensor and / or at least one camera (22). Method (100) according to one of the preceding claims, wherein the at least one material quality parameter (2) indicates at least one of a material composition, a grain size of the material, a surface quality, and / or a material condition. Method (100) according to one of the preceding claims, wherein the at least one laser cutting parameter (5) indicates at least one of a laser cutting power, a laser cutting feed, a focus position, a focus diameter, a nozzle position, and / or a laser cutting gas pressure. Method (100) according to one of the preceding claims, wherein the method (100) further comprises the following further steps (112, 114, 116): - generating measurement data (6) relating to the workpiece parts (44), the at least one workpiece (40) and / or the laser cutting process by means of at least one sensor and / or at least one camera (22), - analyzing the measurement data (6) to determine an actual workpiece part quality (7) of the workpiece parts (44), and - Adjusting the at least one laser cutting parameter (5) based on the determined actual workpiece part quality (7), in particular in comparison to a predetermined target workpiece part quality (4). Method (100) according to claim 8, wherein the steps of generating, analyzing, and adjusting are repeated, in particular until the actual workpiece part quality (7) corresponds at least to the predetermined workpiece part quality (4). Method (100) according to claim 8 or 9, wherein the at least one sensor and / or the at least one camera (22) comprises at least one of a slag expulsion unit for detecting a spray jet during laser cutting, a spark detection unit for detecting a spark size and / or spark brightness during laser cutting, a line spectroscopy sensor for detecting spectral lines during laser cutting, and a hyperspectral camera for detecting a temperature profile during laser cutting.Method (100) according to one of claims 8 to 10, wherein the at least one sensor and / or the at least one camera (22) are a multi-detection system with at least two of a sensor and / or a camera (22). Laser cutting machine (10) for laser cutting workpiece parts (44) from at least one workpiece (40) by means of a laser beam (1) from a laser cutting head (24) of the laser cutting machine (10), wherein the laser cutting machine (10) comprises: - a determination module (51) for determining at least one material quality parameter (2) of a material quality of the at least one workpiece (40), - a determination module (54) for determining at least one laser cutting parameter (5) for laser cutting the workpiece parts (44), wherein the at least one laser cutting parameter (5) is determined as a function of the at least one determined material quality parameter (2), and - a control module (57) for controlling the laser cutting of the workpiece parts (44) from the at least one workpiece (40) by means of the laser beam (1) from the laser cutting head (24) using the at least one determined laser cutting parameter (5). The laser cutting machine (10) according to claim 12, wherein the laser cutting machine (10) further comprises a further determination module (52) for determining a machine state parameter (3) of a machine state of the laser cutting machine (10), and the determination module (54) is configured to also determine the at least one laser cutting parameter (5) as a function of the at least one determined machine state parameter (3). Laser cutting machine (10) according to claim 13, wherein the further determination module (52) is or comprises a machine documentation module, by which the machine state parameters (3) are documented. Laser cutting machine (10) according to one of claims 12 to 14, wherein the laser cutting machine (10) further comprises: - at least one sensor and / or at least one camera (22) for generating measurement data (6) relating to the workpiece parts (44), the at least one workpiece (40) and / or the laser cutting process, - an analysis module (55) for analyzing the measurement data (6) to determine an actual workpiece part quality (7) of the workpiece parts (44), and - an adaptation module (56) for adapting the at least one laser cutting parameter (5) on the basis of the determined actual workpiece part quality (7), in particular in comparison to a predetermined target workpiece part quality (4).

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