Adjustment aid for a laser processing device

Abstract

The invention relates to an adjustment aid (20) for a laser processing device (1), comprising a housing (21) which accommodates at least three light sources that emit collimated light, wherein a first light source is denoted a master light source and the further light sources are denoted reference light sources, wherein a first light beam (16) from the master light source and a second and a third light beam (17, 18) from the reference light sources can emerge from the housing (21) in spaced apart fashion at respective different emergence locations; in this context, provision is made for the reference light sources or the emergence points of the second and third light beams from the reference light sources to be movably mounted in the housing (21) such that the directions of the second and the third light beam can each be adjusted, preferably manually, by means of actuators such that the first and second light beams and the first and third light beams can intersect at respective different distances from the adjustment aid (20).

Description

[0001] BOCKHORNI www.patguarci.de

[0002] Thomas Fischli Linthlistrasse 4 8868 Oberurnen

[0003] Switzerland

[0004] VAT ID: DE 31 9 186 450

[0005] Munich, November 29, 2024 T 96249 WO

[0006] The invention relates to an adjustment aid, a laser processing device and a method for adjusting the positions of a working laser beam of a laser processing device that can be focused by means of a lens.

[0007] STATE OF THE ART

[0008] More and more companies are demanding product traceability and anti-counterfeiting measures. This requires reliable marking systems that can withstand the corrosion of critical data such as serial numbers, barcodes, and logos on manufactured components. The market is being driven by the increasing use of laser marking for brand identification, identification, and aesthetic customization.

[0009] Galvano laser marking machines are particularly attractive due to their remarkable resolution and high-speed marking capabilities, as they produce legible and durable markings even on complex or delicate surfaces. Galvo laser marking machines utilize high-precision galvanometer scanners to quickly and accurately position a focused laser beam on a workpiece surface. This enables the precise marking, engraving, or etching of a wide variety of materials, including composites, metals, plastics, glass, and ceramics. Numerous industries, including automotive, aerospace, electronics, medical devices, jewelry, and packaging, utilize these systems extensively.

[0010] The market for galvo laser marking machines is primarily driven by technological advancements, such as the integration of fiber lasers for increased reliability and efficiency, and the creation of user-friendly software interfaces for ease of operation. Further drivers of market growth include the introduction of compact and modular systems for smaller manufacturers and the integration of automation features for seamless integration into production lines. The galvo laser marking machine market is highly competitive, as both established competitors and innovative startups constantly strive to improve the functionality, price, and performance of their products.

[0011] Thanks to ongoing advancements in laser technology, the galvo laser marking machine industry is undergoing a significant transformation towards greater efficiency and precision. To meet the expectations of various sectors, manufacturers are gradually integrating features such as enhanced automation, improved software functionality, and faster processing rates. Furthermore, environmentally friendly options and customization are becoming increasingly important to address evolving customer preferences and regulatory requirements.

[0012] The development of ultrafast galvanometer scanners is driven by the need for more complex designs and faster production cycles. The rapid beam deflection speeds of these scanners enable high production rates and precise marking on a range of materials. This trend is particularly important for components used in electronics, medical devices, and automobiles, where accurate identification and traceability are essential.

[0013] Robots and automation systems are also being integrated into galvo laser marking machines thanks to the emergence of Industry 4.0 principles. This enables seamless integration of the systems into production lines, data analysis, adaptive marking processes, and real-time monitoring. Automation and galvo laser marking work together to maximize manufacturing productivity and reduce human error.

[0014] Due to their portability, effectiveness, and ability to mark a wide variety of materials, fiber lasers currently dominate the market for galvo laser marking machines. However, alternative laser sources are increasingly being researched. UV lasers, for example, are gaining popularity in applications requiring ultra-fine marking on sensitive materials such as plastics and polymers. Furthermore, the potential of femtosecond lasers for cold ablation and 3D marking is being investigated.

[0015] TASK OF INVENTION

[0016] The invention is based on the objective of being able to perform a lens change of a laser processing device quickly and efficiently.

[0017] REVELATION OF THE INVENTION

[0018] To solve the problem, an alignment aid for a laser processing device is proposed, comprising a housing that accommodates at least three light sources emitting collimated light. A first light source is designated as the master light source, and the other light sources as reference light sources. A first light beam from the master light source and a second and third light beam from the reference light sources each exit the housing at different points, spaced apart from one another. The reference light sources, or the points of exit of the second and third light beams of the reference light sources, are movably mounted within the housing, allowing the directions of the second and third light beams to be adjusted, preferably manually, using actuators. This ensures that the first and second light beams, and the first and third light beams, can intersect at varying distances from the alignment aid.

[0019] By adjusting the intersection points of the light beams from the reference light sources with the master light source at varying distances from the alignment aid, this aid can be used in a laser processing machine to "remember" the working positions of the laser processing machine in space. The manual adjustment of the light beam directions allows for easy operation and can be performed even without specially trained personnel. This makes lens changes on the laser processing machine particularly quick and efficient, resulting in significant time savings.

[0020] For example, if the laser processing device is operated with two or more different lenses of different focal lengths, the intersection points of the light rays for the respective lens can be set at the corresponding distances, so that a working point once set for the respective lens can be easily found again in a simple way, namely by finding the corresponding intersection point of the light rays in space.

[0021] The alignment aid expediently includes a number of light sources adapted to the specific application. For example, if it is clear that the laser processing device will be operated alternately with exactly two different lenses of different focal lengths, the alignment aid can be equipped with exactly three light sources. If more lenses are required for the application, the alignment aid can be equipped with the corresponding number of reference light sources. For example, three to ten reference light sources can be provided, preferably three to five.

[0022] The invention is not limited to the type of light source, provided it is capable of emitting collimated light to generate a defined visible point of impact. Ultimately, it should be possible to determine the intersection point of the light beams as precisely as possible by visual observation. This enables precise adjustment of the focal point of the processing laser. The light sources are, for example, and preferably, laser diodes emitting visible light.

[0023] With this invention, it is no longer necessary to measure the settings for each lens multiple times. This saves time and simplifies the process, as the focus is preset and can be used for different applications.

[0024] In advantageous embodiments, the exit point of the light rays is formed by the opening of a movably mounted pipe section. The pipe section can be, for example, a pipe stub, a pipe flange, or the like.

[0025] Advantageously, the light beam from the light source exits the opening of the tube section in a collimated manner, such that a clearly recognizable and sharply defined point of incidence is achieved within the range of the focal length of the lens intended for the respective application, or at the distances between the lens carrier housing and a work surface, or at the adjustment point. Preferably, the incident light points overlap as much as possible at the intersection point, i.e., they are congruent there.

[0026] An adjustment point for the adjustment aid can, for example, be provided on a workpiece carrier, e.g., and preferably exactly in the middle of the workpiece carrier, or on a worktable, or, if a workpiece is located on the workpiece carrier, directly on the workpiece. However, this is not a limitation of the invention.

[0027] Preferably, the actuator forms the movable section of pipe from which the light beam of the light source emerges. The pipe section is dimensioned such that it can be rotated in different directions, for example, by a user's thumb and forefinger. In the case of a pipe flange, the tip of the actuator, i.e., the flange, is particularly easy to manipulate.

[0028] In one possible embodiment, the reference light sources are arranged in a movable sphere or in another way. Alternatively, the reference light sources can be located in the housing of the adjustment aid, e.g., permanently installed there, and their light beams are guided, for example, by means of a light guide through a movable sphere or other movable component. The directions of the light beams from the reference light sources can be adjusted.

[0029] Additionally or alternatively, the master light source may be arranged in a movable sphere or in another way that allows movement. Alternatively, the master light source may be located in the housing of the adjustment aid, e.g., fixed there, and its light beams may be guided through a movable sphere or other movable component.

[0030] The direction of the light beam from the master light source is preferably manually adjustable by means of an actuator to define an adjustment point for the device. Preferably, the actuator is a movable tube section. The tube section is dimensioned such that it can be rotated in different directions, for example, with the thumb and forefinger of a user. In the case of a tube flange, the tip of the actuator, i.e., the flange, is particularly easy to manipulate.

[0031] In preferred embodiments, the respective actuator is rigidly connected to the movably mounted ball. For example, the actuator is designed as a pin or tube section, such as a pipe fitting or pipe flange, which is driven into a blind hole in the ball. Alternatively, and preferably, the ball and the actuator are formed in one piece, e.g., as an injection-molded plastic part or a metal casting, or the like. A number of alternatives are known to those skilled in the art.

[0032] Preferably, the actuator, designed as a tube section, also serves as the light source; alternatively, additional tube sections can be provided as light source points. Even more alternatively, the actuator can be designed as a pin or tube section, with the light source being formed by the surface of a sphere or similar. A multitude of variations are apparent to a specialist.

[0033] In an advantageous embodiment, the light sources can preferably be switched on and off individually by means of switches. It is particularly preferred that the switches are integrated into the housing of the adjustment aid. This results in easy handling of the device, in which, depending on the required setting, the appropriate reference light source is switched on together with the master light source and the intersection point of their light beams is aligned with the adjustment point.

[0034] A laser processing device according to the invention comprises a lens carrier housing having at least one base for connecting a lens and a working laser, wherein the working laser is configured to generate at least one working laser beam that can be focused by means of the connectable lens. The working laser can be arranged in the lens carrier housing or can have its own housing, in which case the laser beam of the working laser is optically guided into the lens carrier housing and through the lens.

[0035] The term "base" is to be understood broadly within the scope of this disclosure and includes any possible direct or indirect means of attaching a lens to the lens carrier housing, e.g. flanges or fittings with threaded connections or clips or the like. The invention also includes a permanently installed lens with a changeable or variably adjustable focal point.

[0036] The laser processing device according to the invention comprises one of the described adjustment aids, wherein the adjustment aid is fixedly connected to the microscope slide housing. Due to the fixed connection of the adjustment aid to the microscope slide housing, it is possible to define and relocate the working points of the working laser beam, which can be focused by means of the lockable lens, with respect to a workpiece to be processed, by aligning the second and third light beams with the first light beam at different distances from the adjustment aid and locking the reference light sources in the respective position.

[0037] A fixed connection means that the adjustment aid moves with the lens carrier housing when it moves in space. For example, the adjustment aid and the lens carrier housing are screwed, welded, riveted, or otherwise directly or indirectly connected to each other. Preferably, the adjustment aid is directly connected to the lens carrier housing. Advantageously, existing laser processing devices can be retrofitted with the adjustment aid by permanently connecting the adjustment aid to the lens carrier housing.

[0038] The operating point of the working laser beam varies depending on the focal length of the lens used. Generally, the operating point of the laser processing device is the focal point (focus) of the working laser beam, but this is not a limitation of the invention.

[0039] In a preferred embodiment, at least the lens carrier housing is height-adjustable and mounted on a stand. For the purposes of this disclosure, the stand is understood to be part of the laser processing device, although this is not a limitation of the invention. Preferably, the lens carrier housing and the working laser are height-adjustable and mounted on the stand. This allows for simple and safe adjustment of different distances between the working laser and a workpiece carrier, or between the working laser and the workpiece located on the workpiece carrier.

[0040] The height adjustment is preferably manual. With manually adjustable intersection points of the light beams from the reference light sources and the master light source, and manually adjustable height, the device is easy to operate without special expertise. In particular, lens changes for applications with different focal lengths can be carried out efficiently and quickly by untrained personnel.

[0041] In a preferred embodiment, the laser processing device is a galvo laser marking machine, as described above. Modern galvo laser marking machines include, for example, a working laser whose working laser beam is focused onto the object to be processed by means of a lens. A laser triangulation device is typically used to adjust the focus of the working laser on the workpiece. The invention is not limited to this and may include other methods for locating and defining the working point.

[0042] In an advantageous embodiment, the laser processing device includes an adjustment device, for example, a laser triangulation device, for setting the focus of the working laser on the workpiece. A single laser beam is generated, reflected, and detected by a sensor to precisely measure the distance between the lens and the work surface. Since such a laser triangulation device for setting the working point of the working laser, for example, its focus, is often already present on existing laser processing devices, the laser processing device can be retrofitted with this adjustment aid to enable efficient and cost-effective lens changes.

[0043] An inventive method for adjusting the positions of a working laser beam of one of the described laser processing devices, which can be focused by means of a lens, in relation to a workpiece to be processed, comprises the following steps:

[0044] First, the first laser beam of the master light source is preferably manually aligned to an adjustment point, for example to the center of the workpiece carrier, using an actuator.

[0045] Then, for a first lens with a first focal length, a first operating point of the laser processing device, for example, the focal point of the working laser beam, is set by determining the distance of the lens carrier housing to a working surface by means of a height adjustment. The operating point of the working laser beam is preferably determined by optical triangulation. The working surface of the working laser beam is, for example, the surface of the workpiece, but in some applications also the surface of the workpiece carrier, although the invention is not limited to this.

[0046] The two steps can be performed in the described order or in reverse. In a further step, the second light beam from the first reference light source is crossed with the first light beam from the master light source, so that the visible points of impact of the first and second light beams coincide at the adjustment point. The exit point of the light beam from the first reference light source is then locked in this position.

[0047] Advantageously, this method allows the first operating point of the first lens with the first focal length to be reliably determined, since at the set distance of the lens carrier housing to the working surface, the light rays of the first reference light source and the master light source intersect, which can be determined by simply looking at it.

[0048] After changing lenses to a second lens with a different focal length than the first, the operating point of the working laser beam is readjusted by resetting the distance between the lens mount and the work surface using the height adjustment. In a further step, the third light beam from the second reference light source is then intersected with the first light beam from the master light source, so that the visible points of impact of the first and third light beams coincide at the adjustment point. The exit point of the light beam from the second reference light source is then locked in this position.

[0049] At this point, the adjustment aid has “stored” two different working points of the working laser beam for two different lenses, so that these can be easily found again even by untrained personnel.

[0050] When changing lenses for a third, fourth, fifth lens, etc. with different focal lengths, the necessary process steps are repeated to lock the laser processing device with the stationary adjustment aid at different heights to the workpiece carrier or workpiece so that it can be located again.

[0051] BRIEF DESCRIPTION OF THE FIGURES

[0052] The invention is described below with reference to the accompanying drawings. These schematically depict the subject matter of the invention.

[0053] They show:

[0054] Figure 1 shows a laser processing device according to an embodiment of the invention in perspective view.

[0055] Figure 2 shows an adjustment aid in a perspective view from an oblique angle above according to an embodiment of the invention.

[0056] Figure 3 shows the adjustment aid from Figure 2 in a perspective view from a low angle.

[0057] Figure 4 shows the adjustment aid from Figure 2 in exploded view.

[0058] Figure 5 shows the adjustment aid from Figure 2 with the housing partially opened in side view.

[0059] Figure 6 shows an assembly of a light source according to an embodiment of the invention in exploded view, and

[0060] Figures 7 to 9 show schematic representations of different operating points of a laser processing device with an adjustment aid according to an embodiment of the invention.

[0061] FORMS OF EXECUTION OF THE INVENTION

[0062] Figure 1 shows a laser processing device 1 in a perspective view from an oblique angle above.

[0063] The laser processing device 1 comprises a lens carrier housing 2, which has at least one base on its underside for connecting a lens 3 (not shown), and a working laser, which in the illustrated embodiment is arranged in a support arm 5 of the laser processing device 1 by way of example but not limiting the invention.

[0064] The support arm 5 is attached to a stand 4 and its height is manually adjustable. The stand 4 is attached to a mounting plate 8 by a foot 7, on which a workpiece carrier 9 is also attached. The stand 4 and the support arm 5 are aligned such that the lens carrier housing 2 with the lens 3 (not shown) can be positioned essentially vertically above the workpiece carrier 9.

[0065] The workpiece carrier 9 is attached to a clamping block 11 by means of adjusting screws 12. A scale 14 is located on the stand 4, from which the distance of the support arm 5, and thus of the lens 3, to the workpiece carrier 9 can be read. The support arm 5 can be manually moved to different distances from the workpiece carrier 9 by means of a height adjustment 6. The height adjustment 6 determines the distance of the lens carrier housing 2 to the work surface. The operating point of the working laser beam is determined, for example, by optical triangulation, as is known from the prior art.

[0066] An adjustment aid 20 according to the invention is permanently connected to the lens carrier housing 2. In the illustrated embodiment, which is not limiting to the invention, a housing 21 of the adjustment aid 20 is screwed to the lens carrier housing 2.

[0067] Without the adjustment aid 20, the laser processing device 1 is known from the prior art. The laser processing device 1 was retrofitted with the adjustment aid 20 to enable a quick and easy lens change with adjustment of the corresponding focal length to the working point.

[0068] By means of the adjustment aid 20 according to the invention, the once-made setting of the operating point of the working laser beam can be “saved” in a way that allows it to be found again.

[0069] The following section describes the adjustment aid 20 in more detail with reference to Figures 2 to 6. Figure 1 shows only the housing 21 and a series of switches 24 for the light sources 22, 23 contained therein. Figure 2 shows an adjustment aid for the laser processing device in Figure 1 in a perspective view from a slightly oblique angle above. The adjustment aid 20 includes, by way of example, five switches 24 integrated into the housing, with which the light sources arranged in the housing 21 can be switched on and off individually.

[0070] In different embodiments, different numbers of light sources 22, 23 can be installed, with a corresponding number of switches 24 being present.

[0071] In the illustrated embodiment, the central light source is a master light source 22. Two reference light sources 23-1, 23-2 are arranged in a row above and two further reference light sources 23-3, 23-4 are arranged below the master light source 22, so that a first light beam from the master light source 22 and further light beams from the reference light sources 23-1, 23-2, 23-3, 23-4 can exit the housing 21 at different exit points spaced apart from each other.

[0072] Figure 3 shows the adjustment aid from Figure 2 in a bottom view. The light sources 22, 23 each comprise actuators 26 in the form of pipe fittings, which are expediently, but not limitingly for the invention, fixed with movably mounted balls 25. The actuators 26 are dimensioned such that they can be gripped with the thumb and forefinger and rotated in different directions due to the movably mounted balls 25. The balls 25 are movably mounted by means of bearing rings 27 and, here purely by way of example, but not limiting to the invention, three locking screws 28.

[0073] After switching on a light source 22, 23, the point of incidence of the light source can be positioned at an adjustment point. First, the light from the master light source 22 is positioned, for example, on the center of the workpiece carrier 9. It is then locked in this position using the adjusting screws 28. The master light source 22 preferably remains in the same position for all lenses used.

[0074] After the operating point of the working laser has been set, for example by optical triangulation using a device not shown, the master light source 22 and one of the reference light sources 23 are aligned by means of the actuators 26 such that their light beams 16, 17 intersect at a desired point in space. The reference light source 23 is then locked in this position using the adjusting screws 28. After changing the lens, this process is repeated for another reference light source 23.

[0075] In the illustrated and described embodiment, it is assumed that the reference light source 23 and the master light source 22 are located in movably mounted spheres 25, which can be locked in their respective positions. Although the invention has been described in the context of movably mounted spheres 25, it is not limited thereto. Within the scope of the present disclosure, the invention also encompasses, for example, other types of movable mounting, or that the light sources 22, 23 can be located outside the spheres 25 and only their light is guided through the sphere 25, for example through an inlet opening, and exits at the outlet flange of the actuator 26.

[0076] Figure 4 shows an exploded view of the adjustment aid 20 according to Figure 2. The housing 21 is shown here as an example, but not as a limitation of the invention, and is made of three individual parts which are clipped together. The housing contains the switch 24 and the assembly of the light sources 22, 23. The light sources 20, 23 are each connected to the switches 24 by means of electrical leads 29.

[0077] In alternative embodiments not shown, a smaller switch can be provided instead of the relatively space-consuming switch 24, and where the reference numeral 24 points in Figure 4, the light sources 22, 23 can be permanently installed in the housing 21, the light from which is introduced into the spheres 25 by means of lines running at the level of the electrical lines 29.

[0078] Figure 5 shows an interior view of the adjustment aid 20 with the housing 21 open. Advantageously, but not limitingly for the invention, the switch 24 for the master light source 22 is arranged at the outer end of the row of switches and is marked with a special symbol. The other switches extend linearly in the same order as the reference light sources 23-1, 23-2, 23-3, 23-4 switched by them.

[0079] Figure 6 shows an assembly with the movable ball 25 and the components supporting it in an exploded view. In one direction, the ball 25 is blocked in its movement by the bearing ring 27 already described with reference to Figure 3. In the opposite direction, the ball 25 is blocked in its movement by another bearing ring 27. The two bearing rings 27 are shown here, by way of example but not as limiting to the invention, held together by means of adjusting screws 28. The distance between the bearing rings 27 can be changed using the adjusting screws 28 and the locknuts 30 attached to them.

[0080] Figure 7 shows a schematic representation of an adjustment aid 20 in a working position. A first lens 3-1 is also shown, positioned at a distance of its focal length from the workpiece carrier 9 or the workpiece 13 located on it, here a honeycomb panel for illustrative purposes only. The focal length of the lens 3-1 can be identified on the scale 14.

[0081] The adjustment aid 20 is now used to make this distance easily locatable. For this purpose, a first light beam 16 from the master light source 22 is generated by actuating the switch 24. The light beam 16 from the master light source 22 is, for example, directed at the center of the workpiece 13. A first reference light source 23-1 is manually adjusted using the actuator 26 so that a second light beam 17-1 from the reference light source 23-1 intersects with the first light beam 16 from the master light source 22 at the adjustment point, the adjustment point being located directly in the center of the workpiece 13 in the illustrated embodiment. The incident light points overlap as much as possible at the adjustment point, or preferably are perfectly congruent there, which facilitates the identification of the working position. The first reference light source 23-1 is fixed in this position.

[0082] After changing the lens, a second lens 3-2, shown in Figure 8, with a different focal length, is inserted into the laser processing device 1 in place of the lens 3-1 shown in Figure 7. After measuring and adjusting the operating point of the laser with respect to the second lens 3-2, a second reference light source 23-2 is adjusted such that a third light beam 17-2 and the first light beam 16 intersect at the adjustment point. At this point, the second reference light source 23-2 is locked in place, as described with reference to Figure 7.

[0083] Figure 9 shows the same situation with a fourth reference light source 23-4 and a third lens 3-3 with an even different focal length. The fourth reference light source 23-4 is aligned by means of the adjusting element 26 so that a fourth light beam 17-4 intersects the first light beam 16 at the adjustment point.

[0084] A quick change of the three lenses shown here, 3-1, 3-2, 3-3, is easily possible in the manner described above.

[0085] The invention is not limited to the embodiments shown. For example, it may be possible to define different operating points with a given laser and a single lens, within an off-focus operating position of the laser. Furthermore, it is of course possible to use one and the same lens with a variable focal length instead of changing lenses. For a given setting in the lens, the operating point of the laser processing device 1 can always be found again for different settings using the adjustment aid.

[0086] REFERENCE MARK LIST

[0087] 1 Laser processing unit; 2 Lens carrier housing; 3, 3-1, 3-2, 3-3 Lens; 4 Stand; 5 Support arm; 6 Height adjustment; 7 Foot; 8 Mounting plate; 9 Workpiece carrier; 10 Work surface; 11 Clamping block; 12 Adjustment screw; 13 Workpiece; 14 Scale; 16 First light beam; 17, 17-1, 17-2, 17-4 Reference light source beam; 19 Fourth light beam; 20 Adjustment aid; 21 Housing; 22 Master light source; 23, 23-1, 23-2, 23-3, 23-4 Reference light source; 24 Switch; 25 Ball; 26 Actuator; 27 Bearing ring; 28 Locking screw; 29 Electrical cable; 30 Lock nut

Claims

Patent claims 1. Adjustment aid (20) for a laser processing device (1) comprising a housing (21) that accommodates at least three light sources (22, 23) which emit collimated light, wherein a first light source is designated as a master light source (22) and the other light sources as reference light sources (23), wherein a first light beam (16) of the master light source (22) and a second and a third light beam (17) of the reference light sources (23) can exit the housing (21) at different exit points spaced apart from one another, characterized in that the reference light sources (23) or the exit points of the second and third light beams (17) of the reference light sources (23) are movably mounted in the housing (21) such that the directions of the second and third light beams (17) can be adjusted, preferably manually, by means of actuators (26) so that the first and second light beams (16, 17) and the first and third light beams are aligned. (16,17) each can cross at different distances from the adjustment aid (20).

2. Adjustment aid (20) according to claim 1 , characterized in that the light sources (22, 23) are designed as laser diodes.

3. Adjustment aid (20) according to one of the preceding claims, characterized in that the adjustment aid (20) comprises 3 to 10 reference light sources (23).

4. Adjustment aid (20) according to one of the preceding claims, characterized in that the exit point of at least one of the light rays (16, 17) is formed by the opening of a movably mounted tube section.

5. Adjustment aid (20) according to claim 4, characterized in that one of the actuating elements (26) forms the movably mounted pipe section.

6. Adjustment aid (20) according to one of the preceding claims, characterized in that at least the reference light sources (23) are arranged in a movably mounted sphere (25) or their light rays (17) are passed through it.

7. Adjustment aid (20) according to claim 6, characterized in that the respective actuating element (26) is firmly connected to the movably mounted ball (26), wherein the ball (25) and the actuating element (26) are preferably formed in one piece.

8. Adjustment aid (20) according to one of the preceding claims, characterized in that the light sources (22, 23) can preferably be switched on and off individually by means of switches (24), wherein the switches (24) are preferably integrated into the housing (21).

9. Laser processing device (1) with a lens carrier housing (2) which has at least one base for connecting a lens (3), and with a working laser which is designed to generate at least one working laser beam which can be focused by means of the connectable lens (3), characterized in that the laser processing device (1) has an adjustment aid (20) according to one of the preceding claims, wherein the adjustment aid (20) is fixedly connected to the lens carrier housing (2) in order to define working points of the working laser beam which can be focused by means of the connectable lens (3) with respect to a workpiece (13) to be processed by aligning the second and third light beams (17) to the first light beam (16) at different distances from the adjustment aid (20) and locking the reference light sources (23) in the respective position.

10. Laser processing device (1) according to claim 9, characterized in that at least the lens carrier housing (2), preferably also the working laser, are height-adjustable on a stand (4) with a preferably manually operable height adjustment (6).

11. Laser processing device (1) according to one of claims 9 or 10, characterized in that the laser processing device (1) comprises an adjustment device, in particular a laser triangulation device, to adjust the focus of the working laser on the workpiece to be processed.

12. Laser processing device (1) according to one of claims 9 to 11 , characterized in that the laser processing device is a galvo laser marking machine.

13. Method for adjusting the position of a working laser beam of a laser processing device (1) according to one of claims 9 to 12, which can be focused by means of a lens (3), with respect to a workpiece (13) to be processed, characterized in that the first light beam (16) of the master light source (22) is preferably manually aligned to an adjustment point, in particular a workpiece carrier (9), by means of the actuating element (26), a first working point, in particular the focal point of the working laser beam, is set for a first lens (3) with a first focal length by means of a height adjustment (6), the second light beam (17) of the first reference light source (23) is crossed with the first light beam (16) of the master light source (22), so that visible points of impact of the first light beam (16) and the second light beam (17) at the adjustment point,in particular the workpiece carrier (9) is covered, and the exit point of the light beam (17) of the first reference light source (23) is locked in this position.

14. Method according to claim 13, characterized in that after a lens change for a second lens (3) with a second focal length different from the first, the working point of the working laser beam is readjusted by redefining the distance of the lens carrier housing (2) to the working surface (10) by means of the height adjustment (6), - 19 - the third light beam (17) of the second reference light source (23) is crossed with the first light beam (16) of the master light source (22), so that visible points of impact of the first light beam (16) and the third light beam (17) coincide at the adjustment point, in particular workpiece carrier (9), and the exit point of the light beam (17) of the second reference light source (23) is locked in position.

15. Method according to claim 13 or 14, characterized in that the operating point of the working laser beam is determined by means of optical triangulation. - 20 -

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