Method for cutting out a component, and laser cutting machine
Patent Information
- Application Number
- PCT/EP2026/057234
- Authority / Receiving Office
- WO · WO
- Patent Type
- Applications
- Current Assignee / Owner
- Priority Date
- 2025-03-25
- Filing Date
- 2026-03-16
- Publication Date
- 2026-10-01
Smart Images
Figure EP2026057234_01102026_PF_FP_ABST
Abstract
Description
[0001] Title: Method for cutting out a component and laser cutting machine
[0002] Description
[0003] The invention relates to a method for cutting out a component from a workpiece and a laser cutting machine.
[0004] Laser cutting machines are typically used to cut components out of a workpiece. The laser cutting machine generates a laser beam for this purpose. It directs the laser beam across the workpiece in such a way that a kerf forms, cutting the component out. In other words, the component is separated from the remaining part of the workpiece, often referred to as the residual grid, by the laser beam. After the component is cut out, it can be removed from the residual grid. However, the component can become jammed and caught in the residual grid during removal.
[0005] The invention aims to provide a method for cutting out a component from a workpiece and a laser cutting machine, each with improved properties, in particular enabling safe and reliable removal.
[0006] The invention solves this problem by providing a method with the features of claim 1 and a laser cutting machine with the features of claim 14. Advantageous embodiments and further developments of the invention are set forth in the dependent claims.
[0007] A method according to the invention serves to cut out a component from a workpiece by creating a cutting gap using a laser beam. The method comprises: defining a target contour of the component; defining or determining the path of the cutting gap for cutting out the component; determining the width of the cutting gap along the path as a function of the target contour of the component; generating the laser beam using a laser beam source; and creating the cutting gap with the determined width by guiding the laser beam across the workpiece. By creating the cutting gap, the component is cut out of the workpiece.
[0008] By determining the width of the cutting gap as a function of the component's target contour, a contour-dependent adjustment of the cutting gap width can be achieved. Particularly with problematic contours or contour sections, a wider cutting gap can be produced, thereby reducing or completely eliminating the risk of the component tilting and / or snagging in the remaining part of the workpiece. Specifically, the contour-dependent width of the cutting gap can allow the component to tilt slightly, for example, by a maximum of 5° or 2°, during removal without the component tilting or snagging in the remaining grid. Therefore, this method enables safe and reliable component removal.
[0009] Another advantage of this method is that the contour-dependent width of the cutting gap minimizes productivity losses, particularly those resulting from increased material consumption. Furthermore, this allows for optimal production of the cutting gap. For example, the feed rate for creating the cutting gap can be varied along its path, ensuring that the component is still manufactured quickly.
[0010] Another aspect of the process is that it enables trouble-free automated component removal. It can also prevent crooked stacks of parts resulting from unremoved internal contours or burrs. In particular, a wider cutting gap can be determined if the target contour has an internal contour smaller than the distance between two adjacent support ribs on which the workpiece rests during the cutting process.
[0011] Another aspect of the process is that it eliminates an additional work step for removing, for example, waste internal contours or unremoved burrs, thereby reducing the manufacturing costs of the component.
[0012] Preferably, the width of the cutting gap along the path can be determined as a function of the desired contour. Determining the width of the cutting gap can be done based on an analysis of the desired contour using an algorithm, in particular a software algorithm. The algorithm can be a recognition algorithm, a comparison algorithm, and / or a machine learning algorithm. The recognition algorithm can include feature extraction and / or feature reduction. The machine learning algorithm can include a neural network, in particular a trained one.
[0013] The algorithm can be configured to detect or identify a region of the target contour that is highly likely to become jammed during component removal. Such a region can be designated as a critical region. The remaining region of the target contour, which is less likely to become jammed during component removal, can be designated as a non-critical region. The algorithm can be configured to determine the width of the cutting gap such that the width of the cutting gap for removing the critical region is larger than the width of the cutting gap for removing the non-critical region. This reduces the probability of the component becoming jammed during removal.
[0014] Determining the width of the cutting gap along the path as a function of the target contour of the component can be done in such a way that problematic sections of the target contour are produced with a larger width of the cutting gap than non-critical sections of the target contour.
[0015] The workpiece can also be referred to as a sheet of material. The workpiece can be in the form of a sheet or plate. In particular, the width and / or length of the workpiece can be more than five times, and in particular ten times, its thickness. The workpiece can have a thickness of at least 4 mm, and in particular 5 mm. For such workpiece thicknesses, the method is particularly advantageous in order to prevent tilting of the component. The thickness of the workpiece can be at most 100 mm, 30 mm, or 10 mm. However, it is also conceivable that the workpiece has a greater thickness.
[0016] The component can be a sheet metal blank. The portion of the workpiece remaining after cutting the component can be referred to as the residue or residual grid. The laser beam can have a power output ranging from 5 kW (kilowatts) to 120 kW, preferably from 8 kW to 20 kW.
[0017] The target contour of the component can be specified electronically, especially in the form of a CAD file.
[0018] If the path of the cutting gap is predetermined, the path of the cutting gap can be adjusted depending on the determined width of the cutting gap.
[0019] When the path of the cutting gap is determined, the determination of the path of the cutting gap can be done simultaneously with the determination of the width of the cutting gap.
[0020] Once the cutting gap has been created, the width of the cutting gap can be measured orthogonally to a direction of the cutting gap.
[0021] The width of the cutting gap can change along its path or remain constant. The width of the cutting gap can be constant along its path if, for example, the entire target contour is identified as the critical area.
[0022] The laser source can be designed as a solid-state laser, in particular in the form of a fiber laser, a disk laser or a rod laser.
[0023] Guiding the laser beam across the workpiece can involve guiding the laser beam along a trajectory for the purpose of creating the cutting gap.
[0024] By creating the cutting gap, the component can be cut out of the workpiece in such a way that the component has a contour that is equal to the target contour.
[0025] In a further development of the process, the component has a first section and a second section. The determined width of the cutting gap for removing the first section of the component has a first value. The determined width of the cutting gap for removing the second section of the component has a second value. The first value of the width is larger than the second value of the width. This further reduces the probability of the component becoming misaligned during removal.
[0026] Another aspect is that this allows the cutting gap to be created more quickly. In particular, the second section can be cut out with a smaller laser beam focus diameter than the first section, meaning that the laser beam strikes the component with a higher intensity during the second section cutting process, allowing the component to be cut out particularly quickly.
[0027] The first section may contain the area of the target contour that is highly likely to become misaligned when the component is removed. The first section may contain the critical area of the target contour. The second section may contain the area of the target contour that is low or very low likely to become misaligned when the component is removed. The second section may contain the non-critical area of the target contour.
[0028] Cutting the component out of the workpiece can include creating the cutting gap along the first section and along the second section.
[0029] In a further development of the method, the first width value is at least 25%, preferably 50%, larger than the second width value. This can be particularly advantageous for short production times and simultaneously safe and reliable removal of the component.
[0030] In other words, the first value of the width can satisfy the condition: a > 1.25 * b, where a is the first value of the width and b is the second value of the width. In particular, the first value of the width can satisfy the conditions: a > 1.5 * b.
[0031] The first width value can be greater than the second width value by at most 300%, and in particular 200%. In other words, the first width value can satisfy the condition: a < 3 * b. Specifically, the first width value can satisfy the conditions: a < 2 * b.
[0032] In a further development of the process, the first section of the component has an internal contour and / or an undercut. This makes the process particularly suitable for cutting out complex components.
[0033] The second section can be free of an inner contour and / or an undercut.
[0034] The inner contour can be formed by a structure located within the component. The inner contour can be independent of any outer contour of the component. The inner contour can be created using a laser beam. The inner contour can be formed, for example, by a hole or a slot.
[0035] The undercut can be described as an undercut. An undercut can be an almost closed contour. An undercut can be an area of the component that is enclosed by at least 50% of its circumference by an area of the workpiece that is not part of the component. An undercut can be an area of the workpiece that is not part of the component and that is enclosed by at least 50% of its circumference by an area of the component. The undercut can be hook-shaped or U-shaped.
[0036] In a further development of the process, creating the cutting gap involves piercing the laser beam into an area of the workpiece that is not part of the component itself. At least one sector of the first section is cut out before the second section is cut out of the workpiece. This allows for the determination of the tilting direction of the component, the internal contour of the waste material, or the slug.
[0037] Creating the cutting gap can involve guiding the laser beam from a piercing point or entry point, where the laser beam is inserted into the area of the workpiece, to the first section.
[0038] In a further development of the process, the laser beam strikes the workpiece during the creation of the cutting slit, forming a laser spot. The area of the laser spot during the cutting of the first section of the component is larger than the area of the laser spot during the cutting of the second section. Changing the size of the laser spot can be done easily. The area of the laser spot during the cutting of the first section can be more than or equal to twice the area of the laser spot during the cutting of the second section.
[0039] The diameter of the laser spot on the workpiece during the cutting of the first section can have a value in the range of 400 pm (micrometers) to 1000 pm, in particular 500 pm to 900 pm. The diameter of the laser spot on the workpiece during the cutting of the second section can have a value in the range of 100 pm to 350 pm, in particular 150 pm to 250 pm.
[0040] In a further development of the process, creating the cutting gap involves focusing the laser beam onto the workpiece using a focusing device. The laser beam is focused using a first magnification ratio for cutting out the first section of the component. The laser beam is focused using a second magnification ratio for cutting out the second section of the component. The values of the first magnification ratio and the second magnification ratio differ. This allows the laser beam to strike the workpiece with a different beam diameter during the cutting of the first section compared to the beam diameter during the cutting of the second section.In particular, the beam diameter of the laser beam for cutting out the first section can be larger than the beam diameter of the laser beam for cutting out the second section.
[0041] The imaging ratio can also be described as magnification. The imaging ratio can be the ratio of the laser beam diameter on the workpiece to the beam diameter of the laser beam at a point that is imaged onto the workpiece by the focusing device.
[0042] For example, the focusing device can be used to focus the laser beam in such a way that a focus is formed downstream of the focusing device in the direction of the laser beam's propagation. During the cutting of the second section, the laser beam can strike the workpiece in such a way that the focus is located at the workpiece. During the cutting of the first section, the laser beam can strike the workpiece in such a way that the focus is not located at the workpiece. In particular, the focus can be positioned between the focusing device and the workpiece. This allows the laser beam to strike the workpiece with a larger beam diameter during the cutting of the first section.
[0043] In a further development of the process, during the creation of the cutting gap, the laser beam is guided section by section from the laser beam source to the workpiece using a waveguide. The waveguide has a cladding and a core. The laser beam for cutting out the first section of the component is guided in the cladding of the waveguide. The laser beam for cutting out the second section of the component is guided in the core of the waveguide. This allows the first and second sections to be cut out on the workpiece with different beam diameters using the waveguide. The waveguide enables the process to be carried out with simple means. In particular, a device that performs the process can be designed compactly using the waveguide.
[0044] The waveguide can be designed as a fiber optic cable. In particular, the waveguide can contain a single optical fiber.
[0045] In a further development of the process, creating the cutting gap involves creating a section of the cutting gap. This section is created by guiding the laser beam along a first trajectory and then along a second trajectory. The first and second trajectories are parallel but offset from each other. In other words, the cutting gap section can be created by two independent and sequential process steps. This allows the size of the laser spot, with which the laser beam strikes the workpiece, to be kept constant. In particular, this allows the size of the laser spot, with which the laser beam strikes the workpiece, to be kept constant during the cutting of the first section and during the cutting of the second section.
[0046] The first section can be cut out by creating the cutting gap section. The cutting gap section can be used to cut out the first section. The cutting gap section cannot be used to cut out the second section.
[0047] The size of the laser spot during the first trajectory and the size of the laser spot during the second trajectory can be the same.
[0048] In a further development of the method, the distance between the first and second trajectories ranges from 25% to 75% of the laser beam diameter on the workpiece. This allows the laser beam to be guided along the first and second trajectories to create the cut gap, resulting in an overlap zone. This ensures that no workpiece material remains between the first and second trajectories after the cut gap is created. In other words, this allows the workpiece to be completely removed between the first and second trajectories using the laser beam.
[0049] In a further development of the process, creating the cutting gap includes producing an additional cutting gap section. This additional cutting gap section is created by guiding the laser beam along a third trajectory and subsequently along a fourth trajectory. The third and fourth trajectories run parallel to each other but are offset. After guiding the laser beam along the first trajectory and then along the third, a connecting element is formed. This prevents unwanted displacement or changes in the position of the component during the cutting process.
[0050] The connecting element can be referred to as a connecting bridge. The connecting element can be designed as a nanojoint or a microjoint. The connecting element can form a fixing point where the component is connected to the rest of the workpiece.
[0051] The connecting element can be positioned between the first cut gap section, which has not yet been fully completed, and the second cut gap section, which has not yet been fully completed.
[0052] The length of the connecting element can be greater than its width. The length of the connecting element can be determined or measured transversely to the first trajectory or transversely to the third trajectory. The width of the connecting element can be determined or measured parallel to the first trajectory or parallel to the third trajectory.
[0053] In a further development of the process, the connecting element is cut by the laser beam after it has been guided along the second trajectory and before it is guided along the fourth trajectory. This reduces the manufacturing time of the component. In particular, it allows the laser beam to be guided continuously over the workpiece at a constant speed.
[0054] In particular, after being guided along the second trajectory, the laser beam can be guided further over the workpiece at a constant speed, cutting through the connecting element, and then guided along the fourth trajectory.
[0055] In a further development of the process, the connecting element is cut by the laser beam after it has been guided along the second trajectory and after it has been guided along the fourth trajectory. This allows the component to be selectively separated from the rest of the workpiece.
[0056] In other words, the fastener can be cut with the laser beam after the initial cutting gap section and the subsequent cutting gap section have been created. This allows the laser beam to be guided across the workpiece for the purpose of cutting the fastener.
[0057] In particular, a number of connecting elements can be formed during the cutting of the component, which are then cut through one after the other in a defined sequence using the laser beam.
[0058] A laser cutting machine according to the invention is designed for cutting out a component from a workpiece by creating a cutting gap using a laser beam. The laser cutting machine comprises a laser beam source and a control unit. The laser beam source is designed for generating the laser beam. The control unit is designed to determine, from a predetermined target contour of the component, the width of the cutting gap along a path of the cutting gap as a function of the target contour of the component for cutting the component out of the workpiece.
[0059] The laser cutting machine can be designed and specifically configured to be operated using a previously described method. The previously given description of the method can also apply to laser cutting machines with identical or functionally equivalent features. The laser cutting machine can have a focusing device for focusing the laser beam onto the workpiece.
[0060] The laser cutting machine can have a beam guidance device for guiding the laser beam across the workpiece. The beam guidance device can include a drive that moves the focusing device across the workpiece.
[0061] Further advantages and advantageous embodiments of the invention can be seen from the figures, their description, and the claims. All features disclosed in the figures, the description, and the claims can be essential to the invention, both individually and in any combination. The figures show:
[0062] Fig. 1 shows a schematic representation of a laser cutting machine for cutting out a component from a workpiece.
[0063] Fig. 2 shows a schematic representation of the workpiece with the cutting gaps to be made for cutting out the component.
[0064] Fig. 3 shows another schematic representation of the workpiece with the cutting gaps to be produced,
[0065] Fig. 4 shows another schematic representation of the laser cutting machine from Fig. 1.
[0066] Fig. 5 shows a schematic representation of a cross-section of a waveguide of the laser cutting machine,
[0067] Fig. 6 shows a schematic representation of a section of the cutting slits,
[0068] Fig. 7 shows a schematic representation of one section of the cutting gap and another section of the cutting gaps.
[0069] Fig. 8 shows a schematic representation of another embodiment of a component with a cutting gap to be produced for cutting out the component.
[0070] Fig. 9 shows a schematic sectional view of the component along a section line IX-IX according to Fig. 8, and
[0071] Fig. 10 shows a schematic representation of a further embodiment of another component. Fig. 1 shows a laser cutting machine 10. The laser cutting machine 10 cuts a component 12 out of a workpiece 14 using a laser beam 16.
[0072] The workpiece 14 is a plate, in particular a metal plate. The width and length of the workpiece 14 are more than five times, in particular ten times, its thickness. In the illustrated embodiment, the workpiece 14 has a thickness in the range of 5 mm to 15 cm.
[0073] The laser cutting machine 10 has a laser beam source 18 for generating the laser beam 16. The laser beam 16 has a power with a typical value in the range of 8 kW to 20 kW, although the power can also deviate from this.
[0074] The laser cutting machine 10 has a waveguide 20 in the form of an optical fiber for guiding the laser beam 16 section by section from the laser beam source 18 to the workpiece 14.
[0075] After passing through the waveguide 20, the laser beam 16 strikes a focusing device 22 of the laser cutting machine 10. The focusing device 22 serves to focus the laser beam 16 onto the workpiece 14. The focusing device 22 has a focusing lens 24, over which the laser beam 16 is guided and by means of which the laser beam 16 is focused onto the workpiece 14.
[0076] The laser beam 16 passes through the focusing lens 24 and is directed onto the workpiece 14 by means of a laser processing head 26. A cutting gas 28 is supplied to the laser processing head 26. The cutting gas 28 can be an inert gas, for example, nitrogen. The cutting gas 28 exits the laser processing head 26 together with the laser beam 16 in such a way that the material of the workpiece 14 is locally melted by the laser beam 16 and the locally melted material of the workpiece 14 is expelled by the cutting gas 28.
[0077] The laser cutting machine 10 has a beam guidance device 30 for guiding the laser beam 16 over the workpiece 14. The beam guidance device 30 is designed as a drive that moves the focusing device 22 together with the laser processing head 26 and a free end of the waveguide 20 in a feed direction 32. This creates a cutting gap in the workpiece 14 and cuts out the component 12 from the workpiece 14. The laser cutting machine 10 has a control unit 34. The control unit 34 can include an electronic computing unit, in particular a computer and / or a microcontroller. The control unit 34 is designed to control the beam guidance device 30 and thereby cause the laser beam 16 to be guided over the workpiece 14, thus cutting out the component 12 from the workpiece 14.
[0078] The control unit 34 is given a target contour of the component 12. Depending on the target contour of the component 12, the control unit 34 determines the profile of the cutting gap required for cutting out the component 12. For this purpose, the control unit 34 has an algorithm, stored within the control unit 34, which calculates the profile of the cutting gap based on the target contour of the component 12.
[0079] Fig. 2 shows the workpiece 14 in a top view. In order to cut out the component 12 from the workpiece 14, the control device 34 has determined a first cutting gap 36 and a second cutting gap 38.
[0080] The first cutting gap 36 is produced to form an outer contour of the component 12. The outer contour is an outer boundary of the component 12.
[0081] The second cutting gap 38 is created to form an inner contour of the component 12. A waste inner contour 40 is formed by means of the second cutting gap 38, which is to be removed after the component 12 has been cut out.
[0082] The waste inner contour 40 has a hook-shaped area that forms an undercut 42. The algorithm recognizes or identifies the undercut 42 as a critical area that is highly likely to jam against the component 12 when the waste inner contour 40 is removed.
[0083] The control unit 34, in particular the algorithm, determines a width of the first cutting gap 36 and a width of the second cutting gap 38. To prevent tilting, the control unit 34 determines the width of the second cutting gap 38 depending on the specified target contour of the component.
[0084] Fig. 3 corresponds to Fig. 2, with the additional feature that the determined width of the cutting gaps 36, 38 is represented by the line thickness. Fig. 3 shows that the first cutting gap 36 has a constant width along its path. The second cutting gap 38 has a variable width along its path. Thus, the component 12 has a first section 44, which is cut out with a first value of the width of the second cutting gap 38, and a second section 46, which is cut out with a second value of the width of the second cutting gap 38. The first value of the width is 25% to 200% greater than the second value of the width. Therefore, the line thickness in Fig. 3 of the second cutting gap 38 is thicker for cutting out the first section 44 than for cutting out the second section 46.
[0085] The second cutting gap 38 has a cutting gap section 60, in which the width of the second cutting gap 38 has the first value, and an additional cutting gap section 62, in which the width of the second cutting gap 38 has the second value. The first section 44 of the component 12 is cut out by means of cutting gap section 60, and the second section 46 of the component 12 is cut out by means of the additional cutting gap section 62. Cutting gap section 60 and the additional cutting gap section 62 are seamlessly adjacent to each other.
[0086] To cut out component 12, the control unit 34 controls the laser beam source 18 such that the laser beam source generates the laser beam 16. The control unit 34 controls the beam guidance device 30 such that the laser beam 16 is guided over the workpiece 14, forming the cutting gaps 36, 38. By creating the cutting gaps 36, 38, component 12 is cut out of the workpiece 14. After the cutting gaps 36, 38 have been created, component 12 has a contour that is equal to the specified target contour.
[0087] During the cutting of the second section 46, the laser beam 16 is focused onto the workpiece 14 by means of the focusing device 22 such that the laser beam 16 forms a focus 48 at the location of the workpiece 14, see Fig. 1. To form the focus 48 at the location of the workpiece 14, the laser beam 16 is focused onto the workpiece 14 by means of the focusing device 22 with a first imaging ratio. In other words, during the cutting of the second section 46, the laser beam 16 strikes the workpiece 14, forming a laser spot 50, the laser spot 50 having a size equal to the size of the focus 48.
[0088] During the cutting of the first section 44, the laser beam 16 is focused onto the workpiece 14 by means of the focusing device 22 such that the focus 48 is located between the workpiece 14 and the focusing device 22, see Fig. 4. This places the focus 48 at a distance 52 from a surface of the workpiece 14. To form the focus 48 at this distance 52 from the workpiece 14, the laser beam 16 is focused onto the workpiece 14 by means of the focusing device 22 using a second imaging ratio.
[0089] The second imaging ratio is achieved by the control unit 34 controlling the beam guidance device 30 in such a way as to increase the distance between the workpiece 14 and the laser processing head 26. This results in a difference between the first and second imaging ratios. In other words, the laser beam 16 strikes the workpiece 14 during the production of the first section 44, forming the laser spot 50, and the laser spot 50 has a size larger than the focus 48. Therefore, the area of the laser spot 50 on the workpiece 14 during the cutting of the first section 44 is larger than the area of the laser spot 50 on the workpiece 14 during the cutting of the second section 46.
[0090] Due to the different sizes of the laser spot 50, the second cutting slit 38 is produced with a different width along its course.
[0091] An alternative approach for cutting out the first section 44 and the second section 46 by creating the second cutting slit 38 with variable width can be achieved by changing the coupling of the laser beam into the waveguide 20. A cross-section of the waveguide 20 is shown in Fig. 5. The waveguide 20 has a core 54, a cladding 56, and a protective sheath 58. The laser beam 16 is coupled into the cladding 56 of the waveguide 20 for cutting out the first section 44 and into the core 54 of the waveguide 20 for cutting out the second section 46. This also allows a laser spot 50 with varying area to be achieved along the path of the second cutting slit 38 on the workpiece 14.
[0092] Another alternative approach for cutting out the first section 44 and the second section 46 by creating the cutting gap 38 with variable width is shown in Figs. 6 and 7. Fig. 6 shows the cutting gap section 60. The cutting gap section 60 is created by guiding the laser beam 16 over the workpiece 14 along a first trajectory 64 and subsequently guiding the laser beam 16 along a second trajectory 66.
[0093] In Fig. 6, the laser spot 50 is shown as a dashed line. The laser beam 16 is guided along the first trajectory 64 in a first feed direction 68, and the laser beam 16 is guided along the second trajectory 66 in a second feed direction 70. The first feed direction 68 and the second feed direction 70 are opposite directions.
[0094] The first trajectory 64 and the second trajectory 66 run parallel to each other and are offset. A distance 72 between the first trajectory 64 and the second trajectory 66 has a value of 25% to 75% of the beam diameter 74 of the laser spot 50 on the workpiece 14. This prevents material from the workpiece 14 from remaining between the two trajectories 64 and 66 after the cutting gap section 60 has been created.
[0095] This allows the size of the laser spot 50 on the workpiece 14 to be kept constant for producing the second cutting gap 38. Although the laser spot 50 has a constant size on the workpiece 14, the second cutting gap 38 is produced with a variable width 78 along its path.
[0096] The first section 44 can be cut out by producing a single cutting gap section 60. Alternatively, the first section 44 can be cut out by producing the cutting gap section 60 and a further cutting gap section 80, see Fig. 7.
[0097] The further section of the cut slit 80 is produced by guiding the laser beam 16 along a third trajectory 82 and subsequently along a fourth trajectory 84. The third trajectory 82 and the fourth trajectory 84 run parallel to each other and are offset from one another. The third trajectory 82 can be a continuation of the first trajectory 64. The fourth trajectory 84 can be a continuation of the second trajectory 66.
[0098] After guiding the laser beam 16 along the first trajectory 64 and after guiding the laser beam 16 along the third trajectory 82, a connecting element 86 forms between the cutting gap section 60 and the further cutting gap section 80. The connecting element 86 is a holding point at which the component 12 is connected to the remaining part of the workpiece 14. The connecting element 86 can be a nanojoint. The length 88 of the connecting element 86 is greater than the width 90 of the connecting element 86.
[0099] The connecting element 86 is cut by the laser beam 16 after the laser beam 16 has been guided along the second trajectory 66 and after the laser beam 16 has been guided along the fourth trajectory 84. However, it is also conceivable that the laser beam 16 is guided over the workpiece in such a way that it is guided along the first trajectory 64 and along the third trajectory 82 before the laser beam 16 is guided along the second trajectory 66 and the fourth trajectory 84. In this case, the cutting of the connecting element 86 can occur after the laser beam has been guided along the second trajectory 66 and before the laser beam 16 has been guided along the fourth trajectory 84.
[0100] In the embodiment shown in Fig. 6 or 7, the first trajectory 64 and the third trajectory 82 serve to create the contour of the component 12. In an alternative embodiment not shown, the second trajectory and / or the fourth trajectory can serve to create the contour of the component.
[0101] In another embodiment not shown, a plurality of connecting elements can be formed during the cutting of the component, which are cut through one after the other in a defined sequence using the laser beam.
[0102] Fig. 3 shows that the second cutting gap 38 is created by inserting the laser beam 16 at a piercing point 92. The piercing point 92 is located in an area of the workpiece 14 that does not form the component 12. In Fig. 3, the piercing point 92 is located within the waste inner contour 40. Subsequently, the laser beam 16 is guided over the workpiece 14 such that it cuts out a sector 94 of the first section 44. The second section 46 is then cut out, followed by the cutting out of the remaining portion of the first section 44.
[0103] Figures 8 and 9 show a further embodiment of a component 12 to be cut out, wherein identical and functionally equivalent elements use the same reference numerals and in this respect reference can be made to the above explanations of the embodiment of Figures 1 to 7, so that essentially only the existing differences are discussed.
[0104] In Fig. 8, the determined width of the cutting gap 38 is represented by the line thickness. The waste inner contour 40 is round. Fig. 9 shows a section through the component 12 during the removal of the waste inner contour 40 from the component 12. Due to the design of the cutting gap 38 with a varying width along its path, the waste inner contour 40 can fall downwards unimpeded from the viewer's perspective in Fig. 9, without becoming jammed in the component 12.
[0105] Fig. 10 shows a further embodiment of a component 12 to be cut out, wherein the same reference numerals are used for identical and functionally equivalent elements and in this respect refer to the above explanations regarding the embodiment of Fig.
[0106] Reference can be made to sections 1 to 7, so that essentially only the existing differences will be addressed.
[0107] The internal contour 40 of the waste shown in Fig. 10 is so complex that the cutting gap 38 is produced with a constant width. In particular, the algorithm recognizes the complex contour and determines the width of the cutting gap 38 as a function of the specified target contour of the component 12 in such a way that tilting is prevented. This results in the cutting gap 38 being produced with a greater width than if the algorithm did not recognize a complex contour. In such a case, the production of the cutting gap 38 can be carried out by forming at least one connecting element 86.
[0108] In another embodiment, not shown, the component is cut out by cutting and separating 6 mm structural steel parts. A 12 kW laser beam is used for cutting. In the first step, the algorithm identifies which contour areas (internal contours or undercuts) of the component could be problematic with regard to jamming or snagging. The algorithm then finds or identifies, for example, a problematic undercut. For this problematic undercut, the cutting gap is to be increased to facilitate cutting out the undercut. First, the component is cut up to the undercut using standard cutting data with nitrogen in a high-speed cutting process. For example, the focus diameter is 210 pm and the feed rate is 14.4 m / min (meters per minute). The cutting gap width is 0.25 mm (millimeters). At the undercut, the laser switches to the fiber cladding to increase the cutting gap.The focus diameter is increased to 840 pm, thereby widening the cutting gap to 1 mm. Before switching to the wider cutting gap, the cutting gap correction must be set to 1 mm, otherwise the component will exhibit dimensional deviations. The critical undercut can then be cut with the larger focus diameter. The feed rate used for this is reduced from 14.4 m / min to 3.6 m / min, a reduction by a factor of 4. After cutting the undercut, the cutting gap correction is again set to 0.25 mm. Subsequently, the focus diameter is reduced back to 210 pm via the fiber optic cable, and the remaining contour can be cut with a feed rate of 14.4 m / min.
Claims
Patent claims 1. Method for cutting out a component (12) from a workpiece (14) by creating a cutting gap (38) using a laser beam (16), wherein the method comprises: Specifying a target contour of the component (12), Specifying or determining a path of the cutting gap (38) for cutting out the component (12), Determining a width (78) of the cutting gap (38) along the path depending on the target contour of the component (12), Generating the laser beam (16) using a laser beam source (18), and creating the cutting gap (38) with the determined width (78) by guiding the laser beam (16) over the workpiece (14), whereby by creating the cutting gap the component (12) is cut out of the workpiece (14).
2. Method according to claim 1, wherein the component (12) has a first section (44) and a second section (46), wherein the determined width (78) of the cutting gap (38) for cutting out the first section (44) of the component (12) has a first value, wherein the determined width (78) of the cutting gap (38) for cutting out the second section (46) of the component (12) has a second value, where the first width value is greater than the second width value.
3. Method according to claim 2, wherein the first value of the width (78) is at least 25%, preferably 50%, greater than the second value of the width (78).
4. Method according to any one of the preceding claims 2 to 3, wherein the first section (44) of the component (12) has an internal contour and / or an undercut.
5. Method according to any one of the preceding claims 2 to 4, wherein the creation of the cutting gap (38) comprises piercing the laser beam (16) into an area of the workpiece (14) that does not form the component (12), whereby at least one sector (94) of the first section (44) is cut out before the second section (46) is cut out of the workpiece (14).
6. Method according to any one of the preceding claims 2 to 5, wherein the laser beam (16) strikes the workpiece (14) during the creation of the cutting gap (38) forming a laser spot (50), wherein the area of the laser spot (50) during the cutting of the first section (44) of the component (12) is larger than the area of the laser spot (50) during the cutting of the second section (46) of the component (12).
7. Method according to any one of the preceding claims 2 to 6, wherein the creation of the cutting gap (38) includes focusing the laser beam (16) onto the workpiece (14) by means of a focusing device (22), wherein the focusing of the laser beam (16) for cutting out the first section (44) of the component (12) is carried out with a first imaging ratio, wherein the focusing of the laser beam (16) for cutting out the second section (46) of the component (12) is carried out with a second imaging ratio, wherein a value of the first imaging ratio and a value of the second imaging ratio differ from each other.
8. Method according to any one of the preceding claims 2 to 7, wherein during the creation of the cutting gap (38) the laser beam (16) is guided section by section by means of a waveguide (20) from the laser beam source (18) to the workpiece (14), wherein the waveguide (20) has a cladding (56) and a core (54), wherein the laser beam (16) is guided in the cladding (56) of the waveguide (20) for cutting out the first section (44) of the component (12), wherein the laser beam (16) is guided in the core (54) of the waveguide (20) for cutting out the second section (46) of the component (12).
9. Method according to any one of the preceding claims 1 to 5, wherein the production of the cutting gap (38) comprises the production of a cutting gap section (60) by guiding the laser beam (16) along a first trajectory (64) and subsequently guiding the laser beam (16) along a second trajectory (66) which runs parallel and offset to the first trajectory (64).
10. Method according to claim 9, wherein a distance (72) between the first trajectory (64) and the second trajectory (66) has a value in the range of 25% to 75% of a beam diameter (74) of the laser beam (16) on the workpiece (14).
11. Method according to any one of the preceding claims 9 to 10, wherein the production of the cutting gap (38) comprises the production of a further cutting gap section (80) by guiding the laser beam (16) along a third trajectory (82) and subsequently guiding the laser beam (16) along a fourth trajectory (84) which runs parallel and offset to the third trajectory (82), wherein a connecting element (86) is formed after guiding the laser beam (16) along the first trajectory (64) and the laser beam (16) along the third trajectory (82).
12. Method according to claim 11, wherein the connecting element (86) is cut by the laser beam (16) after the laser beam (16) has been guided along the second trajectory (66) and before the laser beam (16) has been guided along the fourth trajectory (84).
13. Method according to claim 11 , wherein the connecting element (86) is cut by the laser beam (16) after guiding the laser beam (16) along the second trajectory (66) and after guiding the laser beam (16) along the fourth trajectory (84).
14. Laser cutting machine (10) for cutting out a component (12) from a workpiece (14) by creating a cutting gap (38) using a laser beam (16), comprising: a laser beam source (18) for generating the laser beam (16), and a control device (34) which is designed to determine a width (78) of the cutting gap (38) along a course of the cutting gap (38) from a given target contour of the component (12) as a function of the target contour of the component (12).