Device for a laser coating process

Abstract

Device (1) for a laser coating process, comprising at least the following components: - a laser device (2) for generating a laser beam (3); - a feeding device (4) for feeding at least one welding consumable (5); and - a tool chuck (6) for fixing a rotating workpiece (7); - a feed actuator (8) with a plurality of actuators (26, 29) by means of which a relative linear-radial feed movement of the laser device (2), the feed device (4) and the tool chuck (6) relative to each other can be carried out for coating purposes, and the workpiece is rotatable; and - a control device (9) for controlling the power output of the laser device (2), wherein the laser device (2) is configured to coat a surface (10) of a workpiece (7) fixed in the tool chuck (6) with welding filler material (5) supplied via the feed device (4) and / or to thermally treat this surface (10) under a correspondingly controlled power output, characterized by the fact that the control device (9) is configured to reduce the power output of the laser device (2) below a predetermined power limit and then raise it again at least to the predetermined power limit, synchronized with the delivery movement of the delivery actuator (8), where coating of a surface (10) of a workpiece (7) below the performance limit does not take place, so that the surface (10) of the fixed workpiece (7) is coated according to a predetermined pattern (14) on the surface (10) of the workpiece (7).

Description

[0001] The invention relates to a device for a laser coating process, comprising at least the following components: - a laser device for generating a laser beam; - a feeding device for feeding a welding filler material; - a tool chuck for fixing a workpiece; - a delivery actuator; and - a control device for controlling the power output of the laser device, wherein the laser device is configured to coat a surface of a workpiece fixed in the tool chuck via the feed device with welding filler material supplied and / or to thermally treat this surface with a correspondingly controlled power output. The device is characterized primarily in that the control device is configured to reduce the power output of the laser device below a predetermined power limit and to raise it again at least to the predetermined power limit, synchronized with the feed movement of the feed actuator. wherein coating of a surface of a workpiece below the power limit does not occur. The invention further relates to an engraving method within a laser coating method, a computer program using such an engraving method, and a computer program product using such a computer program.

[0002] Additive manufacturing processes are becoming increasingly attractive for large-scale production. The goal of additive coating processes is usually to provide a base body with a coating that is more suitable for the respective application. This opens up the possibility of using a base body made of a mechanically and / or thermally more suitable material and / or that can be manufactured more cost-effectively. This is well known, for example, in the field of brake discs, cylinder barrels in engine blocks, and pistons for exterior applications.

[0003] Among the additive manufacturing processes, local coating processes, i.e., those that deliver coating material to the processing point in a timely manner, are advantageous in many respects. Among these are laser spraying and laser cladding, for example, extremely high-speed laser cladding [EHLA], as known, for example, from DE 10 2011 100 456 A1. This allows a mostly thin layer to be applied to the surface of a base body within a very short process time, with low energy consumption, efficient use of powder material, and a high bond quality, which in turn can save material depending on the application. However, this also means that the weld paths to be applied must be applied with high precision.In currently known manufacturing processes, this precision depends to a large extent on the skills of the worker at the production machine, where, for example, test tracks are welded and then readjusted by hand.

[0004] US Pat. No. 6,046,426 A from 1996 discloses a method and system for producing complex, three-dimensional, mesh-like objects, wherein the material is provided from a variety of powdered materials. The system includes components that ensure a uniform and continuous flow of powdered materials and focus and localize the flow of powdered materials with respect to a laser beam that melts the powdered material. The system also includes a controller so that the flow of molten powdered materials can map and form complex, three-dimensional, mesh-like objects by layering the molten powdered material. For example, complex, three-dimensional objects can be produced from two or more different materials, allowing the composition of the object to transition from one material to another.

[0005] The disclosure of DE 10 2018 202 203 A1 relates to an arrangement for adjusting a powder flow relative to the central longitudinal axis of an energy beam for a work head designed for powder deposition welding. A device is provided for two- or three-dimensional alignment of the powder feed relative to the central longitudinal axis of the energy beam in a plane oriented perpendicular to the central longitudinal axis of the energy beam. From one side, a linear beam is directed toward the area where the particles of the powdered material collide.Perpendicular to this, an optical detector array is arranged for the spatially resolved detection of intensities and is connected to an electronic evaluation unit designed to determine the shape, size, and / or length of an irradiated area in which intensities exceeding a predefined threshold have been spatially resolved using the optical detector array. The irradiated area extends from the surfaces of particles onto which the laser beam impinges at reduced power during adjustment, to a sub-area of ​​the irradiated area containing powdery particles accelerated toward a workpiece surface, in which the particles heated by the laser beam move divergently.

[0006] DE 10 2019 132 191 A1 relates to a device for laser deposition welding with a plurality of laser deposition welding heads and a method for operating such a device with a laser deposition welding unit with a plurality of laser welding heads arranged thereon for the (quasi-) simultaneous application of material (M) to a surface of a component and one or more conveyor units for supplying the laser deposition welding heads with the material (M) to be applied and one or more laser beam sources for supplying the laser deposition welding heads with laser radiation (L) for carrying out the laser deposition welding.

[0007] US 6,459,951 B1 relates to a direct additive laser manufacturing system with image feedback control. A closed-loop direct laser manufacturing system with feedback control is disclosed. The feedback relates to the actual growth conditions, which are determined by real-time analysis of thermal radiation images. The resulting system can produce components with a multiple improvement in dimensional tolerances and surface quality.

[0008] US Pat. No. 4,323,756 A from 1979 relates to a method for manufacturing objects by sequential layer deposition. A method for producing solid, rapidly solidified metallic objects with an approximately net shape is described, in which multiple thin layers of a starting material are applied to a substrate using an energy beam to melt each layer. The starting material can be in the form of metal powder or wire. Various finished geometries are also described.

[0009] US Pat. No. 4,122,240 A from 1977 relates to a surface treatment for a class of metal objects, entitled "skin melting." The treatment involves melting a thin surface layer of the object using a concentrated energy source within a narrow set of parameters. The melting step is performed to maximize the temperature gradient between the molten and unmelted parts of the object, allowing for extremely rapid cooling and solidification after removal of the energy source, and the formation of unique microstructures. The preferred energy source is a continuous-wave laser, and in the preferred embodiment, a flowing protective gas atmosphere is used to minimize contamination of the melt and plasma formation. The process can be used to produce amorphous surface layers in a specific class of eutectic alloys.In another class of alloys based on transition metals and containing precipitates rich in one or more metalloids, uniquely fine microstructures can be created.

[0010] Based on this, the present invention is based on the object of at least partially overcoming the disadvantages known from the prior art. The features of the invention are derived from the independent claims, for which advantageous embodiments are presented in the dependent claims. The features of the claims can be combined in any technically reasonable manner, whereby the explanations from the following description as well as features from the figures, which comprise additional embodiments of the invention, can also be consulted for this purpose.

[0011] The invention relates to a device for a laser coating process, comprising at least the following components: - a laser device for generating a laser beam; - a feeding device for feeding at least one welding filler material; and - a tool chuck for fixing a rotating workpiece; - a feed actuator, by means of which a relative linear-radial feed movement of the laser device, the feed device and the tool chuck can be carried out for coating, and the workpiece can be rotated; and - a control device for controlling the power output of the laser device, wherein the laser device is designed to coat a surface of a workpiece fixed in the tool chuck via the feed device with welding filler material and / or to thermally treat this surface under a correspondingly controlled power output.

[0012] The device is characterized in particular in that the control device is designed to reduce the power output of the laser device below a predetermined power limit value and to raise it again at least to the predetermined power limit value, synchronized with the feed movement of the feed actuator, whereby coating of a surface of a workpiece below the power limit does not take place, so that the surface of the fixed workpiece is coated depending on a predetermined pattern on the surface of the workpiece.

[0013] In the following, reference is made to the specified axis of rotation whenever, without explicit indication to the contrary, the axial direction, radial direction, or the direction of rotation and corresponding terms are used. Ordinal numbers used in the preceding and following descriptions serve only to clearly distinguish them and do not reflect the order or ranking of the designated components. An ordinal number greater than one does not necessarily imply that another such component must be present.

[0014] The coating device is a laser spraying machine, for thermal coating, or a laser welding machine, for example, for deposition welding, preferably for the aforementioned extremely high-speed laser deposition welding [EHLA]. The coating, for example, for surface finishing, is realized with a material that is supplied as a welding filler material via the feed device as a wire, (liquefied) droplet-shaped, or (solid) powder-shaped. The welding filler material is molten by the laser device or kept in the liquid state, i.e., melted or only partially melted on the outside and / or introduced into a molten pool formed by the laser device in the surface to be coated, thus bonding it to the surface to be coated at the atomic level.

[0015] The laser device is powered by and / or comprises one or more laser sources. The laser beam or the multiple laser beams of the laser device are focused onto one or more laser focuses, wherein the energy density (intensity) for the desired (maximum) thermal input is preferably present only in this area when, controlled by the control device, a predetermined power limit or more power is emitted by the laser device. The laser focus has a spatial extent, for example with a diameter (in a plane parallel to the surface to be coated) of 1 mm [one millimeter] to 12 mm, for example of 1.2 mm to 8 mm, particularly preferably of 3 mm to 4 mm.It should be noted that the area depends on the power of the laser beam used and should have an increasing diameter with increasing power for a desired energy density on the surface to be coated. In one embodiment of the deposition process that can be carried out with the coating device, the intersection point or the interface between the laser focus of the laser device and the surface to be coated is formed outside the area of ​​the highest intensity of the laser beam. Nevertheless, for the sake of simplicity, this intersection between the laser beam and the surface to be coated is referred to here as the laser focus, because at least in laser deposition welding, this intersection point or interface is effective for melting the welding filler material or for thermally treating the surface.

[0016] It should be noted that in one embodiment of the engraving method, as explained in more detail below, the surface to be coated is a surface of the fixed workpiece, which in one embodiment is arranged on the workpiece with the surface to be subsequently coated, for example within the surface to be coated. Such a surface of the fixed workpiece is referred to here for simplicity as the surface to be coated. Preferably, the surface to be coated is not impaired, but only the optical properties are changed, for example (as a result of leveling a roughness) the degree of reflection is increased or a predetermined reflection image is created (for example a drop shape or puddle shape as a result of selective melting of the surface).In another embodiment, the surface of the fixed workpiece is a surface outside of an area to be coated (for the desired function), for example in the case of a brake disc or a piston on the continuous and / or uniformly aligned surface for the respective function but outside the functional surface, i.e. outside the braking surface or the sliding surface. Alternatively, the surface to be coated with the laser device (additionally with the engraving method described in more detail below) is arranged in a section which is not continuous with the functional surface and / or uniformly aligned, but for example on a surface that is angled and / or offset therefrom. This is, for example, a shoulder or, for example, in the case of a brake disc, its cylindrical outer peripheral surface and, in the case of a piston, one of its cover surfaces.

[0017] The feed device for welding consumables is configured, for example, for wire or powder material. A powder nozzle for transporting powder material for powder buildup welding has one (e.g., lateral) or multiple outlets and / or an annular gap outlet, wherein the powder material is transported by means of a gas stream (e.g., air or an inert carrier gas). The powder material is thus conveyed as a powder stream along a powder trajectory by means of the shape of the at least one outlet and (at least approximately) the speed of the gas stream. A more complex feed device for welding consumables or a more complex gas jet must be referred to as a powder focus.The powder focus is defined, for example, in a design coaxial with the laser beam, by a conical arrangement of the plurality of nozzle channels (powder ring as an imaginary ring line through a plurality of points and / or line segments) or by a ring nozzle (circumferential powder ring). Due to the conical design, the coaxial powder ring tapers concentrically to a powder focus. After passing through the powder focus, the powder gas jet diverges along the propagation direction (of the laser beam). In one embodiment, the powder focus is to be aligned relative to the laser focus.

[0018] The tool chuck is designed to clamp, i.e., fix, a rotating workpiece, whereby a defined spatial axis, for example a central rotation axis, of the workpiece can be precisely aligned. As a rule, the workpiece is already finished, except for the coating to be applied or, if necessary, other minor post-processing steps. Precise positioning is therefore necessary. This is preferably supported by a gripper arm and defined gripping surfaces on the workpiece and / or appropriate measuring technology. For example, the tool chuck includes a device for detecting imbalances, whereupon clamping can be corrected or, if balancing of the workpiece has not yet been carried out or may still be added (e.g., within the scope of admissibility), at least appropriate material removal or material addition can be carried out.For the rotating workpiece, the tool chuck is, for example, a collet chuck. The tool chuck itself is preferably integrated into a fixed, possibly adjustable, machine coordinate system (at least within the scope of an adjustment tolerance).

[0019] The feed actuator is configured to feed the laser device (or its laser focus) and the feed device for welding filler material (or its powder focus) relative to the workpiece or its surface to be coated. The feed actuator comprises a plurality of actuators for the translational and rotational movement of the laser device and the feed device for welding filler material and the workpiece. For example, with a brake disc as the workpiece, the feed actuator rotates the brake disc about its rotational axis (fixed in the tool chuck) and guides the laser device and the feed device for welding filler material radially, resulting in an (at least approximately) spiral shape of the deposition track.In addition, a movement axis aligned perpendicular to the surface of the workpiece is often provided. This is intended for workpieces of different sizes and / or for the possibility of clamping the workpiece in the tool chuck of the device for the laser coating process without collision and / or for convenient maintenance or replacement of the laser device and the feed device. In a preferred embodiment, the feed actuator (per spatial axis) can only be moved with sufficient precision for the coating process, for example, in the range of a few millimeters, preferably from 0.1 mm [one tenth of a millimeter] to 1 mm.

[0020] The control device is configured to control or regulate the power output of the laser device. In one embodiment, the control device is provided exclusively for this purpose. In another embodiment, the control device is also configured to control or regulate other components of the device for a laser coating process, for example, the feed actuators and / or the tool chuck.

[0021] The control device comprises a processor and / or a volatile and / or fixed data memory, wherein these are formed by separate units and / or integrated circuits. The control device is connected to the controlled component, i.e., at least the laser device, in a data-transmitting, i.e., communicatively connected manner. Furthermore, the control device, preferably for regulation, is preferably connected to at least one sensor for receiving signals and / or data. In one embodiment, the power output is controlled by the control device using optics, for example, mechanically.Alternatively or additionally, the laser source is controlled by means of the control device so that laser light is provided with a changed intensity, for example by changing the power voltage, coupling or decoupling phases and / or laser sources from a plurality of phases or laser sources.

[0022] Here, it is proposed that the power output of the laser device be synchronized with the feed movement. In previously known applications, only one layer needs to be applied, the relative position of the applied material webs (compare the spiral for a rotating workpiece above) to the workpiece is irrelevant. Precise assignment is particularly difficult when coating rotating workpieces. Here, however, it is proposed that the control device be configured accordingly, and that the power output can be varied in a manner coupled to the feed movement by means of control values ​​for the feed actuators, which control the feed movement, and / or by means of direct path measurement or movement measurement on the components involved in the feed movement (i.e., at least the laser device, the feed device, and / or the tool chuck).The power output can be reduced below a predetermined power limit at which no coating with the feedable or supplied welding filler material takes place, wherein the power output is preferably switched off with a sufficiently large safety margin, particularly preferably to reduce energy consumption within an available reaction time, the laser source or individual phases and / or individual phases from a plurality of sources are switched off or used for other laser devices of other laser consumers. In one embodiment, the power limit is also defined below a desired power output for coating. In any case, coating with the feedable or supplied welding filler material is not possible below the predetermined power limit. This means that the coating can be switched on and off in synchronization with the feed movement of the feed actuator.It is therefore possible to carry out coating or control of the power output of the laser device that is synchronized pixel-precisely with the relative feed movement.

[0023] With the device proposed here for a laser coating process, a depression similar to an engraving can be created in the applied layer during the process, i.e. inline, and thus a pattern can be created in the coating on the surface of the workpiece by omitting a layer of material. In contrast to an embossed or machined engraving to create a pattern, no additional tool and no additional processing time are required. Due to the speed of the controllability of the laser device, a very precise pattern can be created and the degrees of freedom for creating a pattern are at least no less than in subsequent processing processes for creating an engraving. In contrast to embossing, no mechanical load is applied to the coating and the workpiece and therefore no special design and quality assurance is necessary for this processing.In contrast to machining, a suitable rounding at the transition between a coating surface and a pattern recess is intrinsic to the solidification process or the shape (particles or droplets) of the melted or molten material applied during the laser coating process. Examples of the patterns that can be created with this method are shown further below in connection with the engraving process.

[0024] It is further proposed in an advantageous embodiment of the device that the welding filler material is supplied in powder form and is output unsynchronized to the feed movement of the feed actuator.

[0025] In this powder deposition process, such as laser spraying or extremely high-speed laser cladding [EHLA], the powder is fed conventionally, for example continuously, but does not bond to the surface of the workpiece if the power falls below the predetermined power limit. In one embodiment, the powder particles rebound in this operating state and / or are subjected to sufficiently strong shear forces by the transport gas or by means of (for example, enhanced) suction due to low adhesion forces and are released again. Alternatively or additionally, in a subsequent step, (slightly) adhering powder particles are separated by means of suction (for example, more enhanced compared to suction within a coating period), by means of a gas jet (for example, air), and / or by means of brushes.It should be noted that the welding filler material is preferably only added once a predetermined coating area has been reached, so that energy and effort, as well as material loss, are kept to a minimum. In an advantageous embodiment, the feed movement, as defined here, is exclusively a movement within the coating area. The coating area preferably corresponds to the portion of a workpiece surface that is to be coated with the welding filler material, i.e., the surface of the workpiece to be coated. Alternatively, to ensure correct, i.e., as desired, application of the powdered welding filler material, the coating area comprises a feed section within which the laser device is switched off or operated below the predetermined power limit.During this feed section, the workpiece is not coated with the welding filler material.

[0026] In a laser coating process in which several layers are formed to form a layer and the recess also affects several or a lower layer, potentially adhering powder particles are removed in an intermediate step or in the process by means of a tool following the laser device and the feed device.

[0027] It should be noted that (regardless of the type of welding filler material) it is not absolutely necessary to form the depression in the later outer layer, but can also be formed below a layer that will later form the outer surface or several layers adjacent to this outer layer. The material that impacts such a depression in deeper layers compared to the adjacent, i.e. normal, areas will shape this depression accordingly and thus the pattern will be formed on the outside, for example be visible. This is advantageous, for example, if the outer layer performs a protective function, e.g. for improved corrosion resistance, whereas this is not fulfilled by a lower layer, e.g. due to the use of a different welding filler material in lower layers.Another welding filler material in lower layers is advantageous, for example, for forming a bonding layer, for example in a brake disc, which is designed for mechanical and / or thermal mediation between the material of the workpiece or its surface and the material of the functional layer forming the outer layer.

[0028] It is further proposed in an advantageous embodiment of the device that the device further comprises: - a measuring device for detecting coordinates of a point on a surface to be coated of a workpiece fixed in the tool chuck; and - at least one adjusting device for the relative adjustment of the laser device and the feeding device to each other.

[0029] For simple yet highly precise pattern application, it is proposed that a measuring device and an adjustment device be provided. This allows the machine coordinate system and the coordinate system of the fixed workpiece to be aligned.

[0030] The measuring device is configured (e.g., tactilely or optically) to detect a point on the surface to be coated and its position relative to the machine coordinate system. In one embodiment, such a point can be arbitrarily designed. In one embodiment, such a point is clearly defined and reliably machine-detectable based on its shape (e.g., a characteristic elevation or depression) and / or its appearance (e.g., color, reflectance, and other factors). In one embodiment, such a reliably machine-detectable point is a burn-in, which can be introduced into the surface to be coated by the laser device using its thermal input. The measuring device, or rather its measurement result, is preferably more precise with regard to the detected coordinates relative to the machine coordinate system than the feed precision of the feed actuator system.The measuring device is designed, for example, to detect (relative) coordinates in the range below one-tenth of a millimeter, for example from 0.01 µm [one-hundredth of a micrometer] to 10 µm, preferably 0.05 µm to a maximum of 5 µm. In one embodiment, the measuring device comprises a plurality of measuring units which are configured based on different measuring methods, to detect different objects and / or to detect from complementary or redundant viewing angles. For example, one or a plurality of measuring units are provided for detecting the appearance of the penetration, a measuring unit for detecting the depth of the penetration, and a measuring unit for determining the coordinates of the penetration. For example, one or a plurality of measuring units are provided for detecting the laser focus and / or the alignment of the laser focusing lens, and optionally the powder focus.

[0031] The device proposed here for a laser coating process with a power output of the laser device that can be synchronized with the feed movement, or its feed device for welding filler material and the laser device, can be manually aligned, i.e., adjusted, with respect to one another using the adjustment device. Using this adjustment device, the relative alignment of the feed device for welding filler material (e.g., the powder focus) to the laser focus can be adjusted within the range of the precision of the measuring device (e.g., halving, i.e., doubling the tolerance), preferably only in the plane parallel to the surface to be coated. Alternatively, a relative position along the normal to the surface to be coated and / or a relative rotation can also be adjusted using the adjustment device.

[0032] It should be noted that although the feed device for welding filler material is preferably moved by the adjustment device for adjustment purposes, alternatively or additionally the laser device and / or the laser focus (for example by aligning a laser focusing lens) can be adjusted by means of the adjustment device.

[0033] The device proposed here for a laser coating process is adjustable in a process that is at least machine-assisted, allowing the measurement procedure for high-precision engraving to be carried out as often as required, for example, for each workpiece or once during a maintenance cycle. This makes the device suitable for a laser coating process for large-scale production, while simultaneously ensuring high precision and reliable production quality.

[0034] According to a further aspect, an engraving method within a laser coating method is proposed by means of a device according to an embodiment as described above, comprising at least the following steps in the order mentioned: a. Providing a rotary workpiece fixed in the tool chuck; b. by means of the feed actuator, for coating a surface of the workpiece fixed in the tool chuck, starting a relative linear-radial feed movement between the laser device and the feed device and rotating the workpiece fixed in the tool chuck; c. by means of the control device, controlling the power output of the laser device relative to a predetermined power limit value in a manner synchronized with the feed movement, so that the surface of the fixed workpiece is coated depending on a predetermined pattern on the surface of the workpiece.

[0035] The engraving method proposed here can be carried out on the device for a laser coating process in an embodiment as described above. It should be noted that the engraving method does not necessarily exclusively comprise the coating of the surface to be coated.

[0036] The control device is part of the device for the laser coating process (for example a control unit there) or an external unit which is communicatively connected to the device for the laser coating process (or the control unit there).

[0037] In step a., a workpiece is first provided, wherein in one embodiment this step is carried out at least partially in parallel with the start of step b., for example if the paths for changing a machining tool and / or servicing the machining tool (for example, cleaning a nozzle) do not cause a collision despite simultaneous movement. Alternatively, the relative feed movement of step b. is defined such that it begins from a position adjacent to the machining area. Any other movement of the feed actuator that may be necessary can be carried out at any time, for example simultaneously with step a. In such an embodiment, the feed device and the laser device are therefore also provided in step a.

[0038] In step b, the relative feed movement between the workpiece or its surface to be coated and the feed device with the laser device begins and is carried out. In one embodiment, the feed device and the laser device are permanently coupled to one another in terms of movement, whereby preferably only relative adjustment to one another is possible. Alternatively, the laser device and the feed device can be moved separately from one another relative to the workpiece by means of at least one separate actuator each and / or can be coupled to one another, for example, coupled to one another in terms of movement at least within the coating area.In a preferred embodiment, the supply of welding filler material is started at the beginning or before the beginning of the relative feed movement, particularly preferably in the case of a powder-form welding filler material, so that a desired powder flow is reliably established before the laser beam is activated for laser deposition welding.

[0039] It should be noted that in some embodiments, the relative feed movement comprises solely the movement of the workpiece, i.e., the tool chuck. For a rotating workpiece, such as a brake disc or a piston, the workpiece is rotated (preferably exclusively), and the feed device and the laser device are moved (preferably exclusively) linearly and radially relative to the workpiece. For a flat surface or a surface that is (for example, approximately flat and therefore) machined as flat, a relative vertical movement (i.e., axial to the rotational axis of the workpiece) is performed only prior to and / or after completion of the coating process, or not at all.

[0040] In one embodiment, step c. begins immediately with step b. or later in the course of coating. Step c. can be understood as overlapping in time with a coating; because in this case, in a section of the coating area at least one layer is not applied when the surface is coated, so that a depression and / or an elevation and thus a pattern, for example in the manner of an engraving, is formed in the coating. In one embodiment, step c. is carried out exclusively outside of a functional coating, for example the friction layer in the case of a brake disc and the sliding surface in the case of a piston, so that such a pattern does not impair the function. Alternatively or additionally, such a pattern is introduced into the functional surface of the workpiece.

[0041] For this purpose, the laser beam, or rather its intensity or power output, is varied relative to a predetermined power limit, as already explained above. In a simple embodiment, the laser beam is switched on and off, for example by switching the laser source and / or by deflecting the laser beam. By synchronizing the laser beam with the relative feed movement, at least with regard to its power output sufficient for coating, a pattern can be created that is integrated into the coating process, for example during the coating process. Thus, a pattern, for example a brand logo, a serial number, or the like, can be incorporated into the coating on the surface of the workpiece during the process, i.e., inline.

[0042] It should be noted that in conventional laser coating processes, the coating is not synchronized with the relative feed movement. Rather, there is a starting point and an end point when the power output for coating is provided (i.e., above the predetermined power limit). In other words, the coating is temporally superimposed on step c. Furthermore, the precision of the synchronous change in the power output of the laser device for generating a pattern in the process is very high, simply due to the often high feed speeds. Pixel-precise synchronization is therefore implemented. A pixel is preferably the same size or smaller in its extension in the feed direction than the process-dependent extension transverse to the feed direction of the relative feed movement.In one embodiment, such a pixel is as large as the extent of the laser focus on the surface of the workpiece, in which the melting or fusing required for coating takes place. It should be noted that in one embodiment, a pixel has a shape other than a square, for example, rectangular or arcuate. Furthermore, the shape of the depression or elevation formed in the pattern depends on the flow and solidification behavior of the welding filler material as well as the surface to be coated, so that a droplet shape (like a solidified drop of wax on a table surface) often results.

[0043] It is further proposed in an advantageous embodiment of the engraving method that at least one of the following patterns is created by means of step c.: - a contact tip; - a structure; - a logo; - a functional rounding off; and - a water drainage channel.

[0044] A contact tip, for example, is advantageous for creating a defined surface roughness, for example for a friction surface or for a sliding surface, for example in the manner of a lotus effect. A structure is advantageous, for example, for a function, for example a ventilation duct, and / or a design, for example reflection effects or characteristic ribbing. A logo, for example of a brand or other product identification, such as a serial number, is often a desired detail in the (final, i.e. coated) surface of a workpiece for branding and / or clear identifiability (of the individual workpiece and / or the manufacturer). Functional rounding is advantageous, for example, for edges and transitions, whereby it is then possible to deviate from the amount of welding filler material in the remaining area.For some applications, a water drainage channel is advantageous, for example in a brake disc, in order to be able to drain away splash water and rainwater efficiently and to maintain the braking effect of a disc brake to a high degree even when the brake disc is wet.

[0045] It is further proposed in an advantageous embodiment of the engraving method that the engraving method is carried out with a device according to an embodiment as described above, wherein the engraving method is carried out by the control device and further comprises at least the following steps: i. by means of the feed actuator, moving the laser device to a predetermined point on a surface of the workpiece fixed in the tool chuck and remaining there; ii. by means of the feed actuator, the feed device for the welding filler material is moved to the predetermined point on the surface of the fixed workpiece; iii. after step i., using the laser device, determining the relative position of its laser focus to the point on the surface of the fixed workpiece; iv. after steps ii. and iii. displaying the relative position of the laser focus determined in step iii., so that the feed device for welding filler material can be adjusted relative to the displayed relative position of the laser focus and thus relative to the laser focus by means of the adjustment device.

[0046] In this embodiment, the engraving method further comprises an alignment method, which begins with step i., wherein the laser device moves to a predetermined point by means of the feed actuator. This can, but does not have to, be the point at the beginning of step b. This point is on a workpiece that comprises the surface to be coated and, for example, within this surface to be coated, or on a sacrificial workpiece that is not fed into a production result of a (subsequent) coating process. The predetermined point is preferably located outside the surface to be coated. The surface of the fixed workpiece is thus a separate surface from the surface to be coated.Alternatively, it is accepted that at this predetermined point, for example as a result of penetration, a surface property is changed, for example impaired, or even that a coating can no longer be applied at this point.

[0047] The laser device is now (at least after the current adjustment) positioned at the predetermined point and remains there. In the subsequent step iii., the actual relative position of the laser focus to the base body is detected at the predetermined point using the laser device, for example by generating a penetration in the surface of the fixed workpiece and / or by means of a caustic measurement, while the laser device has moved to the predetermined point. It should be noted in advance that the actually detected laser focus (as previously determined) and the predetermined point may differ if a current adjustment of the laser device relative to the machine coordinate system (of the control device) differs. A more detailed explanation of this follows below, and various approaches are presented.The predetermined point has therefore been approached at least according to the machine coordinate system.

[0048] Parallel to, before, or after step i., in step ii., the feed device for welding filler material is aligned to the predetermined point to which the laser device is to be or is to be moved. In an advantageous embodiment, the laser device and the feed device for welding filler material are always moved together by means of the feed actuator, preferably without the possibility of a relative movement by means of the feed actuator. Such a relative movement is then only possible by means of the adjustment device.

[0049] In the final step (iv), the penetration formed in the surface of the fixed workpiece, or the relative position of the laser focus, is recorded using caustic measurement by the measuring device, and its coordinates are recorded in the control unit. During this time, the laser device remains at the point approached in step (i).

[0050] In one embodiment, the feed device for welding filler material is aligned to this detected laser focus based on (sufficiently) precisely known machine-internal coordinate data. This is advantageous if the laser focus forms the basis for the machine coordinate system (see below). In another embodiment, the feed device for welding filler material is started (preferably without welding operation), i.e., a powder stream is discharged, and the position of the feed device for welding filler material (or the powder focus) is detected by the measuring device, and its coordinates are recorded in the control device.

[0051] The feed device for welding filler material (or its powder focus) is then adjusted relative to the laser focus by means of the adjustment device, i.e. the feed device for welding filler material is aligned relative to the laser focus. For a particularly simple embodiment of the engraving process, an embodiment of the coating device is particularly advantageous in which the feed device for welding filler material and the laser device are movable relative to the surface of the fixed workpiece solely by means of a common feed actuator. The adjustment device is then connected in series with the feed actuator relative to the laser device and the feed device for welding filler material, or is designed with a spatial axis as the adjustment direction that deviates from the at least one feed direction of the feed actuator.

[0052] It is further proposed in an advantageous embodiment of the engraving method that in step iii a raised pattern is applied to the surface of the fixed workpiece by means of the laser device.

[0053] This takes advantage of the fact that all components involved in the coating process are essentially correctly configured, and only their relative position needs to be checked or adjusted. The synchronized power output of the laser device allows a raised pattern to be created, for example a raised cross or a cross recessed in one area. In one embodiment, the shape of the raised pattern can be used to determine not only a relative alignment to the workpiece, but also a relative alignment of the laser focus and the focus of the feed device, for example the powder focus of a powder nozzle. This information is, for example, the amount of welding filler material used to form the raised pattern and / or a deviation from a pixel dimension.

[0054] In one embodiment, the raised pattern is leveled again (completely or approximately) in the subsequent coating process by interrupting the coating process by synchronized control of the laser device's power output based on the known position and the shape of the raised pattern, or by applying a smaller number of layers. With a suitable design, such a raised pattern is then no longer visible later and / or has no physical effect relevant to the intended application.

[0055] It is further proposed in an advantageous embodiment of the engraving method that in a step v. after step iii. and before step iv. the laser focus is adjusted, in a sub-step v.1, in order to determine a deviation by means of the measuring device, the coordinates of the predetermined point are compared with the coordinates of the relative position of the laser focus determined in step iii., and preferably the relative position displayed in step iv., and in a sub-step v.2, the laser focus is adjusted relative to a fixed machine coordinate system of the device by means of the feed actuator and / or the adjustment device in accordance with the deviation determined in sub-step v.1.

[0056] This embodiment takes into account that a deviation may also exist between the predetermined point and the detected laser focus (e.g., penetration, elevation pattern, and / or the result of the caustic measurement) due to an (incorrect) current adjustment of the laser focus to the machine coordinate system. In step v., this is compensated for in sub-step v.2, which is carried out analogously to the above description with regard to the powder nozzle or the powder focus. Preferably, only a single penetration, a single elevation pattern is formed, or a single caustic measurement is performed by aligning the laser focus to the machine coordinate system using the feed actuator and / or the adjustment device based on the measurement result in sub-step v.1.

[0057] In an advantageous embodiment, at least a second penetration and / or a second elevation pattern is generated or a second caustic measurement is carried out after the laser focus has been adjusted, wherein particularly preferably (if necessary beforehand) the infeed has been corrected accordingly by means of the infeed actuator. In the latter case, the (not yet adjusted) first and the at least one (adjusted) second detected laser focus overlap. The optionally present adjustment unit for the laser focus and the adjustment unit for the powder nozzle (or the powder focus) are connected in parallel or in series, for example physically acting directly on one another or spaced far apart from one another. For example, the adjustment unit for the laser focus is arranged on the machine bed side of the infeed actuator, i.e. upstream of it, or connected in parallel to it.

[0058] According to a further aspect, a computer program is proposed, comprising a computer program code, wherein the computer program code is executable on at least one computer such that the at least one computer is caused to carry out the engraving method according to an embodiment as described above, wherein at least one unit of the computer: - is arranged in the device for the laser coating process, preferably according to an embodiment as described above; - is configured to communicate with an edge device on which at least part of the computer program code is preferably provided; and / or - is configured to communicate with a cloud on which at least part of the computer program code is preferably provided.

[0059] The engraving method described here, preferably including the alignment method, is computer-implemented according to this embodiment. The computer-implemented engraving method is stored as computer program code. When executed on a computer, for example, comprising a memory unit and a processor, the computer program code causes the computer to execute the engraving method according to an embodiment as described above.

[0060] The computer-implemented engraving method is realized, for example, by a computer program, wherein the computer program comprises computer program code. When executed on a computer, the computer program code causes the computer to carry out the engraving method according to an embodiment as described above. Computer program code is synonymously referred to as one or more instructions or commands that cause a computer to perform a series of operations, which represent, for example, an algorithm and / or other processing methods.

[0061] The computer program is preferably partially or completely executable on a server or a server unit of a cloud system, a handheld device (e.g., a smartphone), and / or on at least one unit of the computer. The term server or server unit refers here to a computer that provides data and / or operational services for one or more other computer-based devices or computers, thus forming the cloud system. For example, one unit of the computer is arranged as an integrated control device, a so-called edge device, near a machine tool and / or is configured to communicate with a cloud, with at least part of the computer program code preferably being provided on the cloud.

[0062] The terms cloud system or computer are used here synonymously with devices known from the prior art. A computer therefore comprises one or more general-purpose processors (CPUs) or microprocessors, RISC processors, GPUs, and / or DSPs. The computer has, for example, additional elements such as memory interfaces or communication interfaces. Alternatively or additionally, the terms refer to a device capable of executing a provided or embedded program, preferably using a standardized programming language (e.g., C++, JavaScript, or Python), and / or controlling and / or accessing data storage devices and / or other devices such as input and output interfaces.The term computer also refers to a plurality of processors or a plurality of (sub-)computers that are interconnected and / or connected and / or otherwise communicatively connected and possibly share one or more other resources, such as memory. A (data) storage device is, for example, a hard disk drive (HDD) or a (non-volatile) solid-state memory, such as ROM or flash memory [Flash EEPROM]. Memory often comprises a plurality of individual physical units or is distributed across a plurality of separate devices, so that it is accessed via data communication, such as package data services. The latter is a decentralized solution, whereby the memory and processors of a plurality of separate computers are used instead of a (single) central server or in addition to a central server.

[0063] According to a further aspect, a computer program product is proposed on which a computer program code is stored, wherein the computer program code is executable on at least one computer such that the at least one computer is caused to carry out the engraving method according to an embodiment as described above, wherein at least one unit of the computer: - is arranged in the device for the laser coating process, preferably according to an embodiment as described above; - is configured to communicate with an edge device on which at least part of the computer program code is preferably provided; and / or - is configured to communicate with a cloud on which at least part of the computer program code is preferably provided.

[0064] As a computer program product comprising the computer program code described above, a medium such as RAM, ROM, an SD card, a memory card, a flash memory card, or a disc, or stored and downloadable on a server, for example, is possible. Once the computer program is made readable via a readout unit, for example, a drive and / or an installation, the computer program code contained therein and the engraving method contained therein, preferably including the alignment method, can be executed by a computer or in communication with a plurality of server units, for example, as described above.

[0065] The invention described above is explained in detail below against the relevant technical background with reference to the accompanying drawings, which show preferred embodiments. The invention is in no way limited by the purely schematic drawings, whereby it should be noted that the drawings are not to scale and are not suitable for defining proportions. It is shown in Fig. 1: a device for a laser coating process in a schematic view with a workpiece; Fig. 2: a coated workpiece with patterns in the surface; Fig. 3: a flow chart for an engraving process within a laser coating process; and Fig. 4: a flowchart of an alignment procedure as part of the engraving process.

[0066] In Fig. 1 shows a device 1 for a laser coating process in a schematic view with a workpiece 7. The workpiece 7 is clamped here by means of the device 1 for coating and is, for example, a brake disc. For this purpose, the workpiece 7 has a surface 10 to be coated (as shown), the upper one, and optionally an opposite rear side (as shown), the lower one. In the state shown, a layer can be applied to the surface 10 to be coated for coating the surface 10 of a base body. For this purpose, the workpiece 7 is clamped in a tool chuck 6 of the device 1 for coating and is held precisely positioned by the latter. In this exemplary embodiment, the tool chuck 6 is, for example, a clamping chuck with a rigid axis of rotation 25, and the workpiece 7 is aligned coaxially to the axis of rotation 25. The axis of rotation 25 is thus aligned perpendicular to the surface 10 to be coated.In the illustrated embodiment, the tool chuck 6 is optionally driven by a rotary drive 26, allowing the workpiece 7 to rotate about the rotation axis 25. The workpiece 7 can preferably be repeatedly and precisely fed to the coordinates by the rotary drive 26 according to a coordinate system. In this embodiment, the rotary drive 26 is part of the feed actuator system 8.

[0067] As shown, a coating unit 27 of the coating device 1 is positioned above the workpiece 7. The coating unit 27 comprises a laser device 2, a control device 9, and a feed device 4. The laser device 2 is configured to emit a laser beam 3, wherein the power output of the laser beam 3 is controllable by the control device 9. The control device 9 is configured such that the power output of the laser beam 3 can be raised or lowered in synchronization with the feed movement of the feed actuator 8. In this embodiment, a welding filler material 5 (for example, a powder material) is focused by the feed device 4 in the form of a cone into a powder focus 20. With the alignment adjusted, the powder focus 20 overlaps with the laser focus 19 of the laser device 2 just above the surface 10 to be coated.A deviation 22 (this is not the distance 28 normal to the surface 10 to be coated) between the surface coordinates of the laser focus 19 and the parallel coordinates of the powder focus 20 is not recognizable in this illustration (compare . Fig. 2). The laser device 2 is formed by a single-beam or multi-beam laser beam 3 (preferably in a protective gas atmosphere). The coating unit 27 shown is configured, for example, for precise high-speed coating using EHLA. As shown, a measuring device 11 (here shown as a camera) is arranged to the left of the coating unit 27, which, for example, measures a point 12 and / or a pattern 14 (see Fig. 2) and transmits the relative position to the machine coordinate system 23 of the laser coating device 1 to the feed actuator 8. The coating unit 27 (here purely optionally itself) can be moved relative to the workpiece 7 radially with respect to the rotation axis 25 (feed) by means of the horizontal actuator 29 of the feed actuator 8. In addition, the coating unit 27 can be fed vertically (i.e., parallel to the rotation axis 25) by means of the vertical actuator 30 of the feed actuator 8.

[0068] The coordinate systems shown here are purely optionally represented as Cartesian coordinate systems, with the z-axis pointing upwards in the image plane, the x-axis pointing to the left in the image plane, and the y-axis pointing out of the image plane. The data and the actuator coordinates 31 (here shown purely symbolically in the horizontal actuator 29) of the feed actuator 8 are processed in the control device 18 or in a computer 24 (here shown purely schematically with a processor 32 and a memory 33), used for control, and compared with each other. A first adjustment unit 34 acts (indirectly) on the feed device 4 in the horizontal direction in the image plane (i.e., the x-direction or the radial direction relative to the rotation axis 25 of the workpiece 7) to the laser device 2.Preferably, the first adjustment unit 34 also includes an adjustment direction out of the image plane (i.e., in the y-direction or in the direction of rotation relative to the rotation axis 25 of the workpiece 7). Purely optionally, the adjustment device 13 further includes a second adjustment unit 35, by means of which the laser focus 19 can be aligned. This second adjustment unit 35 is shown here acting (horizontally) (preferably also in both the x-direction and the y-direction) on the laser focusing lens.

[0069] In Fig. 2 shows a schematic plan view of a coated workpiece 7 with patterns 14 in the surface 10. The workpiece 7 is, for example, a brake disc arranged coaxially to a rotation axis 25, wherein, as shown, a pattern 14, a logo 15 (here purely optionally shown as a brand name) is applied as a depression (in the manner of an engraving) and / or elevation on the surface 10 below the rotation axis 25. Alternatively or additionally, the surface 10 comprises a pattern 14 as a structure, for example as a plurality of contact points (not visible) for a defined roughness or an effect for draining water and / or dirt. Furthermore, a (purely optional) single water drainage channel 17 for a plurality of water drainage channels 17 is shown here parspro-toto. In one embodiment, a point 12 is coated by means of an elevation pattern 21 using a laser coating process (cf. Fig. 3) is applied to the surface 10, whereby the coordinates of the position of the laser focus 19 are determined by means of a measuring device 11 (as shown in Fig. 1). For example, with correct adjustment, the elevation pattern 21 should be arranged concentrically to the crosshairs shown. Accordingly, the relative alignment of the laser device 2 to the workpiece 7 is adjustable. In an advantageous embodiment, during powder build-up welding, a deviation 22 in the relative alignment between the laser focus 19 and the powder focus 20 can also be determined and adjusted due to the shape of the elevation pattern 21. The surface 10 of the workpiece 7 is coated exclusively within a coating area 36 (shown here as the width of a circular ring), wherein the relative feed movement and thus the generation of a pattern 14 takes place within this coating area 36.

[0070] In this exemplary embodiment, the coating of the surface 10 of the workpiece 7 is provided with a functional rounding 16, here for example at the radially outer edge of the coating (or at the transition from the coating area 36 to the area of ​​the surface 10 of the workpiece 7 not to be coated) and / or at a water drainage channel 17.

[0071] In Fig. Figure 3 shows a flowchart for an engraving process within a laser coating process. In step a, a workpiece 7 is first provided, with the feed device 4 and the laser device 2 preferably also being provided.

[0072] In step b, the relative feed movement between the workpiece 7 or its surface 10 to be coated and the feed device 4 is carried out with the laser device 2. In a preferred embodiment, the feeding of welding filler material 5 is started at the beginning of or before the beginning of the relative feed movement, particularly preferably in the case of a powdered welding filler material 5, so that a desired powder flow is reliably established before the laser beam 3 is activated for laser deposition welding.

[0073] Step c. can be understood as temporally overlapping with a coating, because in this case, in a section of the coating area 36, ​​at least one layer is not applied when coating the surface 10, so that a depression and / or an elevation and thus a pattern 14, for example in the manner of an engraving, is formed in the coating.

[0074] For this purpose, the laser beam 3, or rather its intensity or power output, is varied relative to a predetermined power limit. In a simple embodiment, the laser beam 3 is switched on and off.

[0075] In Fig. Figure 4 shows a flow chart of an alignment process as part of the engraving process. In step i, the laser device 2 moves to a predetermined point 12 by means of the feed actuator 8. This point 12 is on a workpiece 7, which comprises the surface 10 to be coated and, for example, within this surface 10 to be coated (cf. Fig. 2).

[0076] Parallel to, before, or after step i., in step ii., the feed device 4 for welding filler material 5 is aligned to the predetermined point 12 to which the laser device 2 is or is to be moved. Thus, with correct adjustment, welding filler material 5 would be fed into the laser focus 19.

[0077] In the subsequent step iii., the actual relative position of the laser focus 19 to the base body is detected at the predetermined point 12 by means of the laser device 2, for example by generating a raised pattern 21 in the surface 10 of the fixed workpiece 7, while the laser device 2 is moving to the predetermined point 12.

[0078] In an advantageous embodiment, an (optional) step v. is executed with the substeps v.1 and v.2. Substep v.1 takes into account that a deviation 22 may also exist between the predetermined point 12 and the detected laser focus 19 (for example, the elevation pattern 21) due to an (incorrect) current adjustment of the laser focus 19 to the machine coordinate system 23. Therefore, in substep v.1, this deviation 22 of the predetermined point 12 from the coordinates of the relative position determined in step iii. is determined using the measuring device 11.

[0079] In sub-step v.2, this deviation 22 is then compensated. The compensation of the deviation 22 is performed in such a way that only a single elevation pattern 21 is formed. Based on the measurement result from sub-step v.1, the laser focus 19 is aligned to the machine coordinate system 23 by means of the feed actuator 8 and / or the adjustment device 13, thus ensuring the compensation of the deviation 22.

[0080] In an advantageous embodiment, at least a second elevation pattern 21 is generated after the adjustment of the laser focus 19 has taken place, wherein particularly preferably (if necessary beforehand) the delivery has been corrected accordingly by means of the delivery actuator 8.

[0081] In the final step iv., possibly simultaneously with or before step v., the raised pattern 21 formed on the surface 10 of the fixed workpiece 7 is detected by the measuring device 11, and its coordinates are recorded in the control device 18. During this time, the laser device 2 remains at the point 12 approached in step i.

[0082] The alignment method described here within the engraving process is computer-implemented, i.e., executable on a computer 24 using computer program code. For example, a unit of the computer 24 is arranged as an integrated control device 18, a so-called edge device, near a machine tool and / or configured to communicate with a cloud, wherein at least part of the computer program code is preferably provided on the cloud.

[0083] The laser coating device proposed here enables synchronized coating of a workpiece surface. List of reference symbols 1 device for laser coating 2 Laser device 3 laser beam 4 Feeding device 5 Welding consumables 6 tool chucks 7 Workpiece 8 Delivery actuators 9 Control device 10 Surface 11 Measuring device 12 point 13 Adjustment device 14 patterns 15 Logo 16 Functional rounding 17 Water drainage channel 18 Control device 19 Laser Focus 20 Powder Focus 21 survey patterns 22 Deviation 23 Machine coordinate system 24 computers 25 Rotation axis 26 Rotary drive 27 Coating unit 28 distance 29 horizontal adjusters 30 vertical adjusters 31 actuator coordinates 32 processor 33 storage 34 first adjustment unit 35 second adjustment unit 36 Coating area

Claims

[1] Device (1) for a laser coating process, comprising at least the following components: - a laser device (2) for generating a laser beam (3); - a feeding device (4) for feeding at least one welding filler material (5); and - a tool chuck (6) for fixing a rotary workpiece (7); - a feed actuator (8) with a plurality of actuators (26, 29), by means of which a relative linear-radial feed movement of the laser device (2), the feed device (4) and the tool chuck (6) can be carried out to one another for coating, and the workpiece can be rotated; and - a control device (9) for controlling the power output of the laser device (2), wherein the laser device (2) is designed to coat a surface (10) of a workpiece (7) fixed in the tool chuck (6) via the feed device (4) with welding filler material (5) and / or to thermally treat this surface (10) under a correspondingly controlled power output, characterized by , that the control device (9) is designed to reduce the power output of the laser device (2) below a predetermined power limit value and to raise it again at least to the predetermined power limit value, synchronized with the feed movement of the feed actuator (8), wherein a coating of a surface (10) of a workpiece (7) below the power limit does not take place, so that the surface (10) of the fixed workpiece (7) is coated depending on a predetermined pattern (14) on the surface (10) of the workpiece (7). [2] Device (1) according to claim 1, wherein the welding filler material (5) is supplied in powder form and is output unsynchronized to the feed movement of the feed actuator (8). [3] Device (1) according to claim 1 or claim 2, wherein the device (1) further comprises: - a measuring device (11) for detecting coordinates of a point (12) on a surface (10) to be coated of a workpiece (7) fixed in the tool chuck (6); and - at least one adjusting device (13) for adjusting the laser device (2) and the feeding device (4) relative to one another. [4] Engraving process within a laser coating process by means of a device (1) according to one of the preceding claims, comprising at least the following steps in the order mentioned: a. Providing a rotary workpiece (7) fixed in the tool chuck (6); b. by means of the feed actuator (8), for coating a surface (10) of the workpiece (7) fixed in the tool chuck (6), starting a relative linear-radial feed movement between the laser device (2) and the feed device (4) and rotating the workpiece (7) fixed in the tool chuck (6); c. by means of the control device (9), controlling the power output of the laser device (2) relative to a predetermined power limit value, synchronized with the feed movement, so that the surface (10) of the fixed workpiece (7) is coated depending on a predetermined pattern (14) on the surface (10) of the workpiece (7). [5] Engraving method according to claim 4, wherein by means of step c. at least one of the following patterns (14) is created: - a contact tip; - a structure; - a logo (15); - a functional rounding (16); and - a water drainage channel (17). [6] An engraving method according to claim 4 or claim 5, wherein the engraving method is carried out with a device (1) according to claim 3, wherein the engraving method is carried out by the control device (18) and further comprises at least the following steps: i. by means of the feed actuator (8), moving the laser device (2) to a predetermined point (12) on a surface (10) of the workpiece (7) fixed in the tool chuck (6) and remaining there; ii. by means of the feed actuator (8), with the feed device (4) for the welding filler material (5) moving to the predetermined point (12) on the surface (10) of the fixed workpiece (7); iii.after step i., by means of the laser device (2), determining the relative position of its laser focus (19) to the point (12) on the surface (10) of the fixed workpiece (7); iv.after steps ii. and iii. displaying the relative position of the laser focus (19) determined in step iii., so that by means of the adjusting device (13), the feed device (4) for welding filler material (5) can be adjusted relative to the displayed relative position of the laser focus (19) and thus relative to the laser focus (19). [7] Engraving method according to claim 6, wherein in step iii a raised pattern (21) is applied to the surface (10) of the fixed workpiece (7) by means of the laser device (2). [8] An engraving method according to claim 6 or claim 7, wherein in a step v. after step iii. and before step iv. the laser focus (19) is adjusted, in a sub-step v.1, in order to determine a deviation (22) by means of the measuring device (11), the coordinates of the predetermined point (12) are compared with the coordinates of the relative position of the laser focus (19) determined in step iii., and in that in a sub-step v.2, according to the deviation (22) determined in sub-step v.1, the laser focus (19) is adjusted relative to a fixed machine coordinate system (23) of the device (1) by means of the feed actuator (8) and / or by means of the adjusting device (13). [9] Computer program, comprising a computer program code, wherein the computer program code is executable on at least one computer (24) such that the at least one computer (24) is caused to carry out the engraving method according to one of Claim 4 to Claim 8, wherein at least one unit of the computer (24): - is arranged in the device (1) for the laser coating process according to one of claims 1 to 3; - is configured to communicate with an edge device; and / or - is set up to communicate with a cloud. [10] Computer program product on which a computer program code is stored, wherein the computer program code is executable on at least one computer (24) such that the at least one computer (24) is caused to carry out the engraving method according to one of Claim 4 to Claim 8, wherein at least one unit of the computer (24): - is arranged in the device (1) for the laser coating process according to one of claims 1 to 3; - is configured to communicate with an edge device; and / or - is set up to communicate with a cloud.

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