Production of improved nozzle discs by means of laser machining

Abstract

The invention relates to an improved nozzle disc for use in a fluid transfer device, in particular an atomiser, and a laser machining device as well as an arrangement and a method for producing such a nozzle disc by means of laser machining. The nozzle disc has a nozzle geometry with a taper factor, i.e. a ratio of the surface area of a nozzle inlet opening to the surface area of a nozzle outlet opening, of 10 or more, in particular 20 or more, particularly preferably 100 or more. The device comprises a laser beam source for emitting a laser beam to laser optics, wherein by means of a beam-shaping element the laser beam can be split into a plurality of grid-like partial beams, and a controller having a control unit for controlling the laser beam source and the laser optics, wherein the control unit controls the laser beam source and / or the laser optics such that the partial beams generated by the laser optics simultaneously drill a plurality of nozzle openings in a first desired grid arrangement and drill each of the nozzle openings with a desired nozzle geometry completely or partially in the blank.

Description

[0001] Production of improved nozzle discs by laser processing

[0002] The present invention relates to a device and a method for producing improved nozzle disks comprising a plurality of nozzle openings by means of laser processing, wherein the nozzle openings have a desired nozzle geometry which is optimized for the discharge of aerosols with an advantageous droplet size distribution.

[0003] Various types of nebulizers for generating a fine-droplet medication mist from a medication liquid are known in the art. One type operates on the principle that the medication liquid applied to a nozzle disc with a plurality of outlet holes is released as a fine-droplet mist through vibrations of the membrane on an outlet side opposite the medication side. The outlet holes, or nozzle holes / openings, or simply nozzles, typically have a cross-section that varies along their shape to achieve specific fluid transport properties through the nozzle. Such nozzle discs are used not only in nebulizers but also in other fluid transfer devices, such as pumps or filters.

[0004] In a pump, effective fluid transport is to be achieved by means of the diaphragm. For this purpose, the diaphragm is usually moved back and forth periodically, or in pumps with a static diaphragm, the fluid is passed over the diaphragm by means of a piston that is moved back and forth periodically. When moving in one direction, fluid is pushed through the nozzles of the diaphragm, and when moving in the opposite direction, it is pushed back again. In order to achieve effective fluid transport in a desired direction, averaged over the movement cycle, nozzles with a cross-section that is not symmetrical to the plane of the diaphragm are used. In particular, nozzles in which the cross-section widens from one side to the opposite side pointing in the desired transport direction.

[0005] Such pumps, which are based on a back-and-forth moving diaphragm, have the advantage of being mechanically simpler than rotary pumps. Miniaturization is also easier. This is offset by the disadvantage of higher power consumption per volume transported, i.e., lower energy efficiency. Optimizing the nozzle cross-sections or cross-sectional shapes is important here to minimize power consumption as much as possible.

[0006] The goal of filters is to recover particles suspended in a fluid. To ensure this, the nozzles must have a diameter that is smaller than all linear dimensions of the particles to be retained. For a perforated membrane of the type described above to be used effectively as a filter, it is therefore important that the sizes of the individual nozzles differ as little as possible, otherwise uniform and reliable filtration cannot be ensured.

[0007] Perforated membranes in the form of nozzle discs of the type described above are also used in nebulizers, where they are also known as mesh membranes. The goal here is to deliver a droplet mist with droplet sizes of 5 pm or less, provided that respirable droplets are desired.

[0008] A mesh membrane is used in the aerosol generator of a nebulizer in such a way that the medication liquid is applied to one inlet side. If the membrane is then set into periodic oscillation in the direction perpendicular to the surface of the membrane, this causes pressure fluctuations in the fluid applied to the inlet side, forcing it through the nozzles and dispensing it as a fine mist droplet on the opposite outlet side. The droplet size and, as another important parameter, the efficiency—that is, the energy efficiency and the percentage of medication liquid that is actually dispensed as mist and not condensed on the outlet side of the membrane—should be as high as possible.This efficiency depends on various factors, such as the average diameter of the nozzles, the change in cross-section along the nozzles and the presence of surfaces without unevenness inside the nozzle or at the nozzle inlet or outlet opening.

[0009] European Patent Application EP 1295647 A1, for example, discloses a nozzle disk in which the nozzles have two distinctly different sections along their path, namely an approximately cylindrical nozzle throat with a smaller diameter and a continuous region adjoining the nozzle throat. According to this document, the transition between the nozzle throat and the widening region should not be continuous, but rather have a bend, as this would advantageously prevent any liquid remaining in the nozzle after droplet discharge from being completely ejected from the nozzle, which would result in the nozzle being completely filled with liquid again when the membrane springs back.

[0010] The nozzles have a monotonically tapered geometry with a taper factor, i.e. a ratio of nozzle inlet area to nozzle outlet area, of significantly greater than one, more precisely in the range between 10 and 50.

[0011] This document also discloses a manufacturing method for such nozzle disks using laser drilling. This method uses a two-step process, whereby the widening area of ​​the nozzle is formed in a first step and, after changing the laser focus, the neck area is formed in a second step. To achieve the smoothest and most uniform nozzle inner surface possible, an electropolishing step is then recommended to remove sharp surface structures. The disadvantage here is that the method thus represents a three-step process in which the parameters of the position of the laser focus and the applied laser energy must be controlled very precisely, especially during laser drilling. Furthermore, this method is not suitable for cutting out or shaping the contour of the membrane.

[0012] In contrast, the applicant's patent application DE 10 2020 110 404.9 proposes a simplified and improved manufacturing process in which the nozzles of the nozzle disks are manufactured by laser drilling, but the contour, i.e., the outline, is formed by etching. During etching, a photosensitive material is applied to a membrane surface in a known manner and then exposed to light of a wavelength to which this material is sensitive via a mask. The exposed area is then removed by a chemical bath, and the actual etching fluid is then applied to create the nozzle contour.

[0013] The disadvantage of this process, however, is that the etching of the contours takes a comparatively long time and must be carried out in an apparatus separate from the production of the nozzles.

[0014] The patent specification DE 10 2014 200 633 B3 discloses a laser processing device for processing the surface of a workpiece, in which a laser beam bundle can be displaced in parallel by means of a rotation unit rotating around an optical axis, wherein the displaced laser beam bundle can be fanned out into a plurality of partial beam bundles by means of a divergence unit, the partial beam bundles are each focused, some partial beam bundles are removed, angles of rays of the partial beam bundles to one another are each reduced, the remaining partial beam bundles are deflected in a time-dependent manner and can each be focused.

[0015] The published patent application DE 10 2004 043 895 A1 shows a system and a method for delivering (laser) energy onto a substrate, in which a main beam is split into a plurality of partial beams, which are then directed to selectable locations on the substrate by means of independently positionable beam control elements in order to produce desired structures there.

[0016] The aforementioned publications do not propose any method for controlling the geometry of the machined structures, nor does they propose layer-by-layer processing. Their use in the production of nozzle disks is also not considered.

[0017] International publication WO 2007 / 041460 A2 discloses a laser processing system for the accelerated machining of frequently repeating, similar structures. In particular, an embodiment is proposed in which multiple structures can be machined simultaneously by splitting a laser beam from a laser beam source into several sub-beams. Splitting occurs by diffraction of the laser beam in a variable diffractive element in the form of an acousto-optical modulator. The use of the laser processing device for drilling the several hundred nozzle openings of a nozzle disk is also proposed, with achievable production times of 0.6–0.7 seconds being stated, provided the sub-beams are optically moved across the surface of the raw material.The laser beam source is to be controlled by a signal from an analyzer mounted on the back of the raw material, which monitors the individual holes for penetration. The laser beam is switched off individually for each opening as soon as the detected brightness exceeds a threshold.

[0018] A disadvantage of the control system used there is that it does not monitor the nozzle shape, i.e., the cross-sectional profile, because the light intensity passing through it only allows limited conclusions about this. Likewise, this document is silent regarding the definition of the nozzle disk contours.

[0019] Against this background, the present invention has set itself the task of finding improved nozzle discs with nozzle geometries which, when used in a nebulizer, lead to an advantageous droplet size distribution, whereby they can be manufactured quickly and economically using laser processing methods.

[0020] Furthermore, it is an object of the invention to develop laser processing devices and arrangements optimized for the production of such nozzle disks and nozzle disk production methods using these.

[0021] This object is achieved by a device according to claim 1, an arrangement comprising at least one such device according to claim 9, a manufacturing method using the device and / or arrangement according to claim 15 and a nozzle disc according to claim 20.

[0022] According to the invention, the device comprises a laser beam source for emitting a laser beam to a first laser optics system having a beam input for receiving the laser beam and a beam output, wherein the laser beam can be divided into a plurality of partial beams arranged in a grid by means of a beam-shaping element of the laser optics, a control of the system having a control unit for controlling the laser beam source and the laser optics. The control unit is configured according to the invention to control the laser beam source and / or the laser optics in such a way that the partial beams generated by the laser optics simultaneously drill a first plurality of nozzle openings in a desired grid arrangement into the raw material strip within a region of a nozzle disk to be produced, wherein each of the nozzle openings has a desired geometry with a taper factor, i.e. a ratio of nozzle inlet to nozzle outlet area, of greater than one.

[0023] The nozzle geometry can have a taper factor of 50 or more, especially 100 or more. Since the size of the nozzle inlet area is limited by the distance between adjacent nozzle openings, the key to this is

[0024] Furthermore, the nozzle geometry can have a monotonically tapered shape.

[0025] When drilling the nozzle openings according to the invention, material is removed in a targeted manner by precisely applying local laser pulses. Their pulse energy and duration can be selected such that the material of the blank is vaporized abruptly. This benefits the precision of material removal and largely avoids material artifacts at the nozzle edges. High pulse energies and short pulse durations are recommended for this purpose, so that each partial beam used for processing receives a corresponding pulse energy. Depending on the bore shape and geometry, partial beam pulse energies are used, in particular a fluence (energy per area) of at least the ablation threshold of the raw material up to approximately 5 J / cm 2 .

[0026] In some designs, the control system guides the multitude of partial jets in multiple layers over the surface of the raw material strip, so that the desired geometry of the nozzle openings is created layer by layer. Layer by layer, or more precisely horizontal layer by layer, means that the desired nozzle geometry is first completed to a first depth of, for example, 1 / 10 of the total depth, which also corresponds to the thickness of the machined nozzle disk blank, within the achievable manufacturing tolerance, before drilling deeper, for example a second layer is completed to a second depth of 2 / 10 or 3 / 10 of the total depth. This process is continued layer by layer until the nozzle opening is completed. As can be seen from the values ​​given as examples, the individual layers removed can be of the same or different thicknesses.

[0027] Alternatively, some or all of the nozzle openings can be drilled in layers, not just horizontally, but in other ways, either layer by layer or not layer by layer. The laser ablation of the blank material to be removed can, for example, be performed in layers that are adapted to the contour of the inner surface of the desired nozzle geometry. In this case, a central cylindrical channel, i.e., one containing the nozzle axis, can be drilled first, and then the inner surface of this channel can be ablated layer by layer until the desired nozzle geometry is completed. The vertical extension of the layers decreases with increasing distance from the nozzle axis.

[0028] Alternatively, the above-described removal process of vertical or at least non-horizontal layers can also be carried out from the outside inwards, i.e. working from the edge of the nozzle inlet opening inwards. In both cases, each of the partial beams of the laser beam is guided over the surface of the blank in discrete concentric circles or, alternatively, in a spiral pattern in the area of ​​the nozzle opening to be drilled by the respective partial beam. In the case of concentric circles, the laser beam should be briefly switched off or the beam power greatly reduced when changing from one to the next to avoid deviations from the desired geometry. The partial beams can be moved at a constant or variable speed. In order to realize the desired geometry, which prescribes a target drilling depth d(x,y) for each point (x,y) of the nozzle opening, care should be taken to ensure that the product of traversing speed u, beam cross-section or-diameter w and target depth d(X, Y) at the current beam center (X, Y) is at any time proportional to the beam power or, in the case of pulsed beam sources, the period-averaged beam power, i.e.

[0029] P = kwud(X, Y) applies with the material-dependent constant k.

[0030] The number of nozzles that can be drilled simultaneously corresponds to the number of partial beams determined by the diffractive element of the laser optics. This can be designed in such a way that a large number of partial beams can be generated, for example, several hundred or thousand partial beams. In some embodiments, for example, 140 or more partial beams can be generated. A structured quartz glass disc can be used as the diffractive element, for example.

[0031] The arrangement according to the invention comprises one or more laser processing devices (laser drills) according to the invention, which are combined with a belt conveyor system which can transport a raw material belt provided on a roll in a conveying direction past the beam output of the laser optics of the laser drill(s).

[0032] In the inventive method for manufacturing nozzle disks using the inventive device, preferably all or a majority of the nozzles of a nozzle disk are drilled out simultaneously. In preferred embodiments of the manufacturing method in which an arrangement according to the invention is used, the laser optics can be focused on a point in another area of ​​the metal strip serving as the blank after all nozzle openings of a nozzle disk have been drilled in order to drill the nozzles of another nozzle disk. For this purpose, the sheet metal is preferably moved past the stationary optics, either in a stop-and-go process or continuously. With continuous movement, there is no need for frequent starting and stopping of the material strip and the associated waiting times until vibrations subside. This benefits the manufacturing speed. If the highest possible precision is desired, a stop-and-go process is preferred.

[0033] In this case, the material strip, such as sheet metal, in particular stainless steel sheet, can be unwound from a reel on which it is wound. The sheet metal provided with the drilled holes can be rewound onto a second reel for further processing at a different location or at a different time, or further processing can take place directly, for example, in an arrangement further developed according to the subclaims or the embodiments below.

[0034] In principle, the first laser optics of the laser drill can also be designed in such a way that it is capable of flexibly splitting off one or more contour beams from the input laser beam by means of a bypass, which serve to shape the outlines of the nozzle disks. This can be done, for example, by moving a single laser beam in the desired contour over the surface of the material to be processed. Alternatively, the laser beam can also be imprinted with any desired shape, such as a circular ring, by the optics. However, for machining the contours of the nozzle disks, a dedicated device for completely or partially separating the nozzle disks is preferably provided, which device is arranged before or after the laser drill - viewed in the direction of travel of the belt.Of the two possible arrangements, the latter is preferred because in this case the separation device can orient itself on the already existing nozzle hole areas when positioning the contour to be created, i.e. the area of ​​the drilled nozzle holes is detected and the contour which completely or partially separates the nozzle disk is introduced in such a way that it has a desired position relative to the respective detected nozzle hole area. For example and preferably in such a way that the nozzle hole area is located centrally, in particular concentrically, in the nozzle disk. Conversely, however, it is also conceivable and encompassed by the invention to first create the nozzle disk contour using the separation device and then drill the nozzle holes, it then being the laser drill which, with corresponding optical detection means, detects the contour of one or more nozzle holes.each nozzle disc and positions the nozzle holes so that they have the desired position relative to the contour.

[0035] In a partial separation, the connection between the nozzle disc and the rest of the material strip is not completely severed, but only along a portion of the contour. In particular, one, two, three, or more webs can initially be left standing and only removed in a subsequent contouring step by a device following the separation device in the direction of travel of the strip, for example, a pressing tool comprising a punch and a die.

[0036] This separation device is preferably a laser cutter / laser separator with its own laser optics and laser beam source. On the one hand, this fundamentally reduces the production speed due to the possibility of parallel processing of the material strip at different points. On the other hand, it also enables the use of devices optimized for the respective purpose: on the one hand, a laser drill, which can drill as many nozzle openings as possible simultaneously, where high accuracy is essential; on the other hand, the laser cutter, which can create the linear contours of the nozzle disks as quickly as possible, whereby the accuracy requirements are lower than for nozzle openings, whose size is in the micrometer range.

[0037] The arrangement can further comprise a forming device by means of which a desired three-dimensional shape can be imprinted on the nozzle disks. Here, the flat and planar material of the strip or nozzle disk is plastically deformed before or after contouring in the direction perpendicular to the surface of the strip. In particular, the forming device serves to form a dome-shaped or cupola-shaped region in which the nozzle holes are located, in particular centrally or even concentrically. The forming device can be a pressing tool such as the one used to create the contour of the nozzle disk or to completely separate the pre-contoured nozzle disks (preferably by means of a laser separator) from the rest of the strip. It is particularly preferred to use the same pressing tool for the three-dimensional embossing of the nozzle disk that is also used for the (complete) separation.In principle, the forming device can also be a separate device and can be arranged before or after the separation device or the laser drill.

[0038] The method according to the invention for producing a nozzle disk comprises moving the raw material strip past the beam exit of the first laser optics, thereby impinging on the surface of the material, for example a metal sheet, with the plurality of partial beams arranged in a grid shape generated by the first laser optics, and thereby simultaneously drilling a first plurality of grid-shaped nozzle openings in the region of the nozzle disks to be produced, wherein during drilling the plurality of partial beams are guided in several layers over the surface of the raw material strip and thereby a desired geometry of the nozzle openings is generated layer by layer.

[0039] In addition, the contour of the nozzle discs is machined out of the raw material. This can generally be done before, during, or after the nozzle openings have been drilled. In the first case, the correct positioning of the numerous nozzle openings relative to the contour would have to be ensured during the subsequent drilling of the holes; in the latter case, the same applies in reverse for the positioning of the contour relative to the nozzle openings. In both cases, this can be achieved using a camera system, for example, which recognizes the respective existing structure and passes its position on to the processing device downstream in the conveying direction of the belt, in the first case the laser drill, in the latter case the laser separator. In simple test systems, manual adjustment of the blank to be processed by an operator is another possible solution; this is particularly useful for larger batch sizes or high-volume production runs.parallel processing of several blanks or several nozzle discs to be formed is no longer economical or even practical.

[0040] If the contouring of a nozzle disk is to be performed while the corresponding nozzle openings are being drilled, it is preferable to expand the laser drill's optics to include the option of emitting a contour laser beam that can be moved separately or shaped according to the contour. This is achieved via a bypass. A distinction must be made here: either the nozzle holes can be created with the beam bundle, or the beam split off by the bypass can be used for this purpose. In some embodiments, these two processing modes can be flexibly selected and switched via the appropriately prepared control system, for example, using suitable software.

[0041] The nozzle disk according to the invention is characterized by the high taper factor of 50 or more, preferably 100 or more, of its nozzle openings. For example, the nozzle inlet and outlet openings can be circular and have a diameter of 20 micrometers or more, preferably 25 micrometers or more, particularly preferably 50 micrometers or more in the case of the inlet opening, and 3 micrometers or less, in particular 2.5 micrometers or less in the case of the outlet opening. The large taper factor results in high flow acceleration and thus flow velocity at the outlet opening, which leads to rapid separation of the liquid emerging from the outlet opening and thus to advantageously small droplet sizes. At the same time, unwanted wetting of the nozzle disk outlet side is reduced. It has been found that the precise shape of the nozzle inner surface does not have a very significant influence on these properties.In particular, a simple cone shape or bell or trumpet shapes that are close to the cone shape produce equally good results.

[0042] By means of the manufacturing method according to the invention using the device and / or arrangement according to the invention, it is possible to quickly and easily form a plurality of nozzle disks, in particular of the type according to the invention, from a strip-shaped raw material. Compared to a combined laser drilling and etching process for producing a nozzle disk, a significant acceleration is achieved, since the comparatively time-consuming etching step is eliminated. Compared to known laser manufacturing processes, a higher precision in the geometry of the drilled holes is achieved. The accelerated production makes it possible to produce customer- and / or drug-specific perforated disks for use in nebulizers, which are optimized for delivering a droplet mist with a desired size distribution tailored to the drug to be administered.

[0043] Further advantageous further training courses, which can be implemented individually or in combination, provided they are not obviously mutually exclusive, will be presented below.

[0044] Preferably, all nozzle holes of a nozzle disk are drilled simultaneously. If the number of partial jets is insufficient for this, alternatively, only one part is drilled simultaneously, each corresponding to an arrangement of the multiple partial jets generated by the diffractive element. This partial jet arrangement is then laterally offset to drill the next plurality of nozzle openings, and so on. Advantageously, the total number of nozzle openings corresponds to an integer multiple of the number of partial jets. For example, with 140 partial jets, 980 nozzle holes can be drilled in 7 steps.

[0045] In some embodiments, the first laser optics comprises a multi-beam laser scanner, by means of which the plurality of grid-like partial beams generated by the diffractive element can be moved in two directions perpendicular to each other and to a beam axis. This allows the partial beam arrangement to be moved freely over the surface of the workpiece.

[0046] This is preferably used to drill a second plurality of nozzle openings which are offset relative to the first. This offset or offset vector particularly preferably originates from the unit cell of the partial beam grating, i.e. is a weighted sum of the basis vectors of the partial beam grating with weighting factors less than 1.0. Thus, for each nozzle opening of the first plurality, there is an associated nozzle opening of the second plurality within the unit cell spanned by the basis vectors. More than one offset vector can also occur. The number of offset vectors, including the zero vector, corresponds to the number of steps required to drill all of the nozzle openings. The offset vectors can be randomly selected within the unit cell, whereby it is only necessary to ensure that the edges of the individual nozzles do not come too close to one another.However, to ensure the most densely packed and homogeneous distribution of the nozzles possible, the offset vectors should preferably also be arranged in a grid pattern. This type of grid arrangement can, but does not have to, correspond to that of the partial jets.

[0047] The grid-like arrangement of the partial beams, as well as the offset vectors, preferably forms a hexagonal grid. However, other grid arrangements of the partial beams and / or offset vectors are also possible, such as triangular, rectangular, or square grids, and different grid types can also be combined.

[0048] In some embodiments of the invention, the beam-shaping element is reconfigurable by appropriate control signals from the process control system, allowing various grating-shaped arrangements of partial beams to be generated. In particular, the grating geometry (triangle, square, hexagon, regular, compressed, grating constant(s), etc.) and the outline or layout of the generated partial beam (rectangular, hexagonal, cross-shaped, star-shaped, hollow, filled, etc.) can be changed. For this purpose, the beam-shaping element preferably comprises an electro-optical element and variable apertures.

[0049] In some embodiments of the present invention, the beam-shaping element is a diffractive element, such as a diffraction grating, and the splitting into partial beams occurs by diffraction of the first laser beam at this grating. Preferably, the zeroth diffraction order, which corresponds to direct transmission, is omitted and only the first diffraction order is used. During the drilling of the nozzle holes of a nozzle disk, in some embodiments of the method according to the invention, the beam-shaping element can be reconfigured so that first a first plurality of nozzle holes with a first configuration, such as a hollow square grating arrangement with a square footprint, are drilled, and subsequently a second plurality of nozzle openings with a different configuration, such as a cross-shaped square grating arrangement, which can have the same or a different grating constant.

[0050] In some embodiments of the invention, a reconfiguration of the jet-shaping element and thus of the grid-like arrangement of partial jets takes place even before the first or one of the further plurality of nozzle openings has been completely drilled. For example, drilling can begin with a first grid arrangement having a first outline and a first hole shape and be carried out to a certain depth, which can correspond to or be smaller than the thickness of the raw material. Then, a first reconfiguration of the jet-shaping element takes place into a second grid arrangement and a second outline, which only includes a first portion of the hole positions of the first grid arrangement, and the partially completed nozzle openings drilled at these positions are further drilled or completed with a second nozzle shape. Furthermore, nozzle openings can also be started at new positions extending beyond the first grid arrangement.Subsequently, a second, third, etc. reconfiguration can take place, in which further partially completed nozzle openings are further drilled and / or finished according to a third, fourth, etc. nozzle shape, or new nozzle openings are started at further positions until finally all nozzle openings with a desired nozzle shape have been completely drilled. For example, in a first step, a first partial jet arrangement corresponding to a hexagonal grid with an outline in the shape of a regular hexagon can be started and, by means of layer-by-layer removal according to the invention in several passes down to a first depth, a first nozzle shape, i.e. a first nozzle cross-sectional profile, can be drilled. Then, in a second step, a reconfiguration of the jet-forming element takes place, in which the hexagonal grid arrangement is retained but the outline is changed to a regular triangle.Using this arrangement, the central nozzle openings are then finished drilling according to a second nozzle shape, i.e., a second nozzle cross-sectional profile. In a subsequent third step, the remaining, not yet completed nozzle openings of the first partial jet arrangement are finished drilling with as few reconfigurations as the contours possible using the jet-shaping element allow, ideally with a single reconfiguration.

[0051] Alternatively or additionally, additional nozzle openings extending beyond the first partial jet arrangement can also be started. For example, in the third step, a reconfiguration can be carried out to form a partial jet arrangement corresponding to the hexagonal grid of the first partial jet arrangement, but with a triangular outline in which the hexagonal outline of the first partial jet arrangement is inscribed, but the outline of the second arrangement is left out. With this third partial jet arrangement, the outer nozzle openings of the first arrangement begun in the first step but not yet completed in the second step are then drilled to a third desired nozzle shape, and additionally, new nozzle openings extending beyond this first arrangement are started with the third nozzle shape.In a subsequent fourth step, with a correspondingly selected fourth partial jet arrangement, the nozzle openings newly started in the third step are then finished drilling according to the third or another nozzle shape, again by removing in horizontal, vertical, or other layers according to the invention. The result in this example is a nozzle opening arrangement with an outline in the shape of an equilateral triangle, in which the nozzle openings of the points of the triangle extending beyond an inscribed area with the outline of a regular hexagon are arranged according to the third, if necessary.in conjunction with another nozzle shape, the nozzle openings of the inscribed hexagonal region, with the exception of a central region inscribed therein with an outline of an equilateral triangle, are drilled with a nozzle shape which is a combination of the first and third nozzle shapes, and the nozzle openings of the central triangular region are drilled with a nozzle shape which is a combination of the first and second nozzle shapes.

[0052] The types of nozzle drilling described herein, i.e. the previously described method with intermediate reconfiguration (reconfiguration before completion of all nozzle openings at the positions exposed to the respective partial beam arrangement) as well as the drilling of the nozzle openings by ablation of horizontal, vertical or inclined layers described at the beginning, can be realized particularly easily in conjunction with a pulsed laser beam source.

[0053] Thus, for example, in some embodiments of the invention, a reconfiguration of the beam-shaping element can also take place between two pulses, so that a first pulse or a first series of pulses with a first configuration, a second pulse or a second series of pulses with a second configuration, etc., are emitted until all desired nozzle openings with the respective desired nozzle shape have been machined.

[0054] The arrangement according to the invention preferably comprises a laser cutting device or a laser separator for cutting out and shaping the contour of the nozzle disks. This laser separator has its own laser optics for this purpose, which creates a cutting laser beam or contour beam from an input laser beam. This can be a focused Gaussian beam that is moved over the surface to create the contour. Alternatively, it is a fanned-out beam or a beam bundle whose shape corresponds to the desired contour. A separate laser beam source of the laser separator preferably serves to provide the cutting laser beam.

[0055] The contour is preferably created using the laser separator after the nozzle openings have been drilled. In order to identify where a nozzle disk contour is to be cut into the still continuous surface of the raw material strip, in preferred embodiments a camera takes images of the material's surface, in which the areas with the drilled nozzle holes are identified using image recognition. The coordinates of these identified areas are then transmitted to the laser separator's control system, allowing it to cut out the desired nozzle disk contour, typically preferably a circular contour, at the corresponding locations around the nozzle opening arrangements. Additionally, other geometries can be incorporated, such as hole circles with a desired diameter.

[0056] The laser beam sources of the laser drill and / or the laser separator / laser cutter are preferably operated in pulsed mode, whereby laser pulses of different durations can be used. For the first laser beam source, to provide at least the laser beams for drilling the nozzle openings, a laser beam source in the femtosecond range is preferred, which allows for greater precision. The pulse duration is preferably in the range of 10 fs to 50 ps. This range is optimal for avoiding heat accumulation and results in a reduced occurrence of material melting and the associated resolidification artifacts, which may have to be removed in complex post-treatment when longer pulses are used. A second laser beam source is preferably used to provide the contour beams. This particularly preferably operates with laser pulses in the picosecond range, with a pulse duration of up to 50 ps.Furthermore, it preferably has a higher power than the first laser beam source, which is preferably used exclusively for generating the drilling beams.

[0057] According to the method according to the invention, which utilizes the laser processing arrangement according to the invention, a sheet metal blank is subjected to drilling beams generated by the first laser beam source and the first laser optics, and the nozzles of the nozzle disks are drilled. Using the first or a further, second laser optics, preferably as part of a separate laser cutting device with its own laser beam source, one or more contour beams are generated, and the contours of the nozzle disks are formed. In this process, the nozzle disk can be separated immediately from the surrounding material, or merely a predetermined breaking point is created, and the nozzle disk is released mechanically in a later or subsequent step. For this purpose, a pressing tool with a punch and a die can be provided, for example.

[0058] More than one laser drill and / or multiple laser separators can be present, such as two, three, four, etc., so that multiple nozzle disks can be processed in parallel. The number of laser drills does not have to correspond to the number of laser separators.

[0059] If multiple laser drills are present, they can be arranged one behind the other in the conveying direction of the material belt. In order to be able to machine multiple nozzle disks simultaneously, the belt is preferably started up periodically to further transport semi-finished nozzle disks and remove unprocessed material areas and then stopped for precise laser drilling of the nozzle openings. Alternatively, a serial arrangement of multiple laser drills can be combined with step-by-step drilling of the nozzle openings if the number of partial beams is fewer than the desired number of nozzle openings. In this case, a first laser drill in the conveying direction would drill a first plurality of nozzle openings, a second laser drill a second plurality offset from the first by an offset vector, and so on, until all the desired nozzle openings have been drilled after the last laser drill has passed.

[0060] In some of these embodiments, all of the laser drills arranged one after the other have a similar reconfigurable beam-shaping element, so that they can also generate a similar grid-like arrangement of partial beams. In particular, a diffractive element is used as the beam-shaping element, which enables the beam from the first laser beam source to be split into the plurality of partial beams by means of diffraction.

[0061] Alternatively, one or more of the laser drills arranged one behind the other can have a different diffractive element, so that the partial beam arrangement generated by it differs from the others. This makes it easier to arrange the nozzle openings so that their outline corresponds to the contour of the nozzle disk. For example, nozzle disks with a round contour are common, and it is usually desired to make the outline of the nozzle opening arrangement as close as possible to a circular shape. If all holes are drilled using partial beams generated by the same diffractive element, this is only possible to a limited extent. A hexagonal arrangement of the partial beams already deviates significantly from a circular shape. By appropriately selecting the offset vectors when drilling all of the nozzles in several steps, a circle can be better approximated.

[0062] However, the use of different diffractive elements would allow the desired shape of the nozzle arrangement to be achieved by different

[0063] TI-shaped sections. For example, a circular nozzle arrangement could be approximated by three rectangular and four triangular sections, one square and four triangular sections, or seven hexagonal and six triangular sections.

[0064] In all of the above-described embodiments, correct positioning of the additional plurality of nozzle openings relative to those already drilled must be ensured. This can be achieved by using a camera system, in particular one camera per laser drill, in conjunction with image recognition. This system detects the position of the drilled holes and transmits this information to the respective laser drill, so that the nozzle openings to be drilled by the laser drill are correctly positioned relative to the existing ones.

[0065] In alternative embodiments of the arrangement according to the invention, several laser drills are arranged next to one another in a transverse direction. The material strip can be moved either in stop-and-go mode, as described above, to increase manufacturing precision, or at a continuous speed for a higher production rate. In either case, a number of nozzle discs corresponding to the number of laser drills will be drilled simultaneously.

[0066] In preferred embodiments of the method, the strip material is cleaned after laser drilling to remove contaminants created during laser drilling, particularly at the nozzle opening edges. An ultrasonic bath, for example, is suitable for this purpose. Furthermore, this cleaning step preferably takes place after drilling but before cutting out the nozzle disk contour.

[0067] To implement this step, the arrangement according to the invention has a cleaning section downstream of the laser drill in the conveying direction of the material strip, which particularly preferably provides an ultrasonic bath for cleaning. Furthermore, this cleaning section is preferably arranged between the laser drill and the laser separator / cutting device.

[0068] Alternatively or additionally, particulate ablation residues can also be removed by laser cleaning. The laser drill(s) themselves are suitable for this purpose. Furthermore, the laser separator(s) can also be used.

[0069] Suitable raw materials for use in the arrangement and method according to the invention are any that can be formed into a thin layer and rolled up. Stainless steel or nickel sheet are particularly interesting for nozzle discs.

[0070] Further properties, advantages, and features of the present invention will become apparent from the preferred embodiments explained below with reference to the figures. These are intended merely to illustrate the invention and in no way limit its generality or scope.

[0071] In detail:

[0072] Fig. 1: A schematic perspective view of an embodiment of the device according to the invention.

[0073] Fig. 2A A schematic section through a blank in which a desired nozzle geometry is machined in horizontal layers.

[0074] Fig. 2B A schematic section through a blank in which a desired nozzle geometry is machined in vertical layers. Fig. 2C A schematic section through a blank in which a desired nozzle geometry is machined in inclined layers.

[0075] Fig. 3: A schematic view from an elevated perspective of a nozzle disk blank during a drilling process in which the material is removed in vertical layers.

[0076] Fig. 4: A schematic side view of an embodiment of the arrangement according to the invention.

[0077] Figure 1 shows a schematic perspective view of an embodiment of a laser processing device according to the invention for producing nozzle disks.

[0078] The laser drill 1 comprises a laser beam source 2, which emits a laser beam 21, which is fed to a laser optics 3. In the laser optics 3, the laser beam 21 first passes through a diffractive beam splitter 310 of the beam-shaping element 31 and is thereby split into a plurality of partial beams. The desired grating arrangement of partial beams is predetermined by a mask 312, which is arranged in the propagation direction of the laser beam or the laser (partial) beams between a first imaging optics 311 and a second imaging optics 313.The partial beam emerging from the second imaging optics 313 in the desired grid arrangement strikes a mirror 332 in the scanner head 33, also referred to as a galvano scanner, which can be pivoted in two axes. The beams are then focused in the form of a plurality of partial beams 32, which have the desired grid arrangement, by the focusing optics 331 onto the area 51 within the blank 5 intended for the nozzle disk to be produced and shown here as a circle. By pivoting the galvano scanner 332 under the control of the control unit 41 of the controller 4, the partial beams can be moved together over the surface of the blank 5, for example in order to drill the nozzle openings layer by layer with the desired geometry in each case according to the invention.

[0079] Detailed view B shows a top view of the nozzle disk area 51. By reconfiguring the jet-shaping element 31 between drilling operations, nozzle openings with different geometries 52a, 52b and grid arrangements can be drilled.

[0080] Figures 2A to 2C illustrate different possibilities for layer-by-layer drilling of nozzle openings of different geometries provided within the scope of the present invention.

[0081] Figure 2A illustrates horizontal layer-by-layer ablation. A nozzle opening 52 with the monotonically tapering (truncated) conical geometry G1 is drilled by successively ablating horizontal layers 522, i.e., layers parallel to the surface of the blank 5, starting from the entry surface 521. For this purpose, the laser (partial) beam is guided in concentric circles or spirally over each layer such that the product of beam width and travel speed is proportional to the (time-averaged, in particular period-averaged) beam power, whereby the proportionality constant depends on the material of the blank and on the thickness or strength of the respective layer 522. The layers 522, 528 can all have the same thickness. Alternatively, the layer thickness can also be adjusted during the drilling process, for example, thicker layers can be ablated with increasing depth.After removing a final layer 528, which creates the nozzle outlet opening 523, the nozzle opening 52 with the desired geometry G1 is completed, except for any necessary post-treatment. Figure 2B illustrates a vertical layer-by-layer removal. The nozzle opening 52 with a monotonically tapered bell-shaped geometry G2 is drilled by removing vertical layers 525, i.e., layers running perpendicular to the surface of the blank 5, starting from the axis of symmetry S of the nozzle opening 52.For this purpose, the laser (partial) beam is guided outwards over each layer in concentric circles or spirals, starting from the axis of symmetry S, such that the product of beam width, travel speed and desired drilling depth D(R) for the current distance R of the beam center from the axis of symmetry is proportional to the (time-averaged, in particular period-averaged) beam power, whereby the proportionality constant depends on the material of the blank. The layers 522, 528 can all have the same thickness. Alternatively, the layer thickness can also be adjusted during the drilling process by changing the beam width and adjusting the distance between adjacent concentric circles or spiral arcs of the path on which the laser beam is guided over the surface of the blank.

[0082] The figure shows the process at the time when a cylindrical central channel 520 has already been created by the layer-by-layer removal described.

[0083] As an alternative to starting at the axis of symmetry S, the ablation can also start at the outer edge of the entrance opening 521 and the laser beam can be guided inwards in concentric circles or spirally.

[0084] To ensure better absorption of the laser energy by the exposed surface of the resulting nozzle opening 52 and to avoid reflection and scattering losses, the layers 525 may not run exactly vertically, but rather form a small angle of between 0 and 10 degrees with the vertical. However, within the scope of the invention, this is considered vertical layer removal.

[0085] Finally, Figure 2C shows a mixed form in which the layer-by-layer removal occurs along inclined layers, which can also be adapted to the nozzle geometry to be created. In this figure, the nozzle opening 52 is intended to have a trumpet-shaped geometry G3. To this end, inclined and increasingly trumpet-shaped layers 527, which slowly approach this desired geometry, are removed in a similar manner to that described above in connection with Figures 2A and 2B.

[0086] The combinations of geometries and layerings illustrated in Figures 2A-20 are merely examples. The illustrated geometries G1-G3 can also be produced with the other illustrated or other conceivable layer removals. Likewise, nozzle disks according to the invention are not limited to the illustrated nozzle geometries G1-G3, but can also have others.

[0087] Figure 3 shows a perspective view of a nozzle disk blank during a drilling process in which material is removed in vertical layers. The partial laser beam 32 is guided at a speed u along a spiral path SB, shown here as an example, over the surface of the blank 5. At the time shown, a portion of the material to be removed has already been removed by the laser ablation, thereby creating the curved trench 52'. The traversing speed u, the average beam power, and the beam width w can be varied during drilling, for example, to meet accuracy requirements in certain parts of the nozzle opening. For example, there are no special requirements for areas of the material to be removed that are not close (measured relative to the beam width) to the future inner surface of the nozzle. The goal here is to remove the material as quickly as possible.This does not apply to locations near the inner surface of the nozzle; here, the desired nozzle geometry should be implemented as precisely as possible, or at least precisely enough. Accordingly, the jet power P, jet width w, and travel speed can be adjusted for locations near the inner surface of the nozzle. For example, the jet power P can be reduced, which may require a corresponding adjustment of the other parameters as well.

[0088] Figure 4 shows schematically an embodiment of an arrangement according to the invention.

[0089] The arrangement 100 comprised a belt conveyor system 9 which transports a raw material strip 95 unwound from a roll 90 by means of a plurality of deflection rollers 92 in a conveying direction V through a plurality of successive processing areas.

[0090] In a first area 101, the raw material strip is guided over a support 934, where the laser drilling of the nozzle openings takes place using laser drills 1a, 1b. As shown, several of these can be arranged one behind the other in the conveying direction V, but additionally several can be arranged side by side (not shown) transversely to the conveying direction V. A side-by-side arrangement enables the simultaneous processing of several adjacent nozzle disks.

[0091] In the illustrated embodiment of the arrangement according to the invention, the laser drills 1a, 1b each comprise a laser beam source which, by means of a reconfigurable beam-shaping element, preferably in the form of a controllable diffraction grating with a downstream aperture arrangement, each feeds a laser beam to a laser optics 3a, 3b, which splits the beam into a bundle of partial beams 32. Depending on the configuration of the beam-shaping element, the partial beam bundles 32 have a different two-dimensional grid-like arrangement of the partial beams and a different outline, created, for example, by means of apertures. Possible grating geometries include, for example, a triangular, quadrangular, or hexagonal grating with different grating constants in both spatial directions transverse to the beam direction. Possible outlines are triangular, rectangular or square, hexagonal, cross-shaped, or star-shaped.Shapes can be cut out within an outer outline, so that (initially) areas without holes remain within the outline.

[0092] According to the invention, the partial beam bundles 32 are guided over the surface of the raw material strip 95 in multiple passes, so that nozzle openings with a desired nozzle shape are drilled at the desired positions by layer-by-layer material removal. In this case, a reconfiguration of the beam-shaping element of the respective laser optics 3a, 3b can be performed for one or all of the laser drills 1a, 1b during processing.

[0093] After a first plurality of nozzle openings have been fully or partially drilled using a first configuration, a second plurality can be drilled. The nozzle openings or nozzle opening positions of this second plurality can all be different from those of the first. For example, the grid geometry and outline of the second plurality can be identical to those of the first, but offset from it by a certain vector. Alternatively, the first and second plurality of nozzle openings (positions) can overlap, i.e. have common nozzle openings (positions). The nozzle openings (positions) of the second plurality of nozzle openings (positions) can also be a subset of those of the first plurality of nozzle openings (positions).For example, after a reconfiguration to a partial jet arrangement with an identical grating geometry but a different outline, a part of the unfinished nozzle openings of the first plurality of nozzle openings can be finished with a different nozzle shape.

[0094] The laser drills are controlled by a process controller 104 comprising a control unit 41 that sends commands to the controlled devices via control lines 43 and in which a control program is stored, as well as an input unit 42 that provides a user interface for writing and modifying the control program. Control unit 41 and input unit 42 are shown as separate devices in Figure 1, but can also be combined into a single device. Furthermore, control unit 41 is not necessarily responsible for the fine control of all degrees of freedom of laser drills 1a, 1b or other devices controlled by them, such as laser separator 96 and / or punch 93. While this is possible, it is inefficient. Preferably, the control unit sends commands from a higher hierarchical level to the controlled devices 1a, 1b, 96, 93, thus ensuring that the nozzle disks are manufactured according to the program.The controlled devices 1a, 1b, 96, 93 preferably each have their own control or regulating units (not shown), which convert the commands from the central control unit 41 into targeted movements of their degrees of freedom or actions of their respective actuators.

[0095] In preferred embodiments, the laser beam sources are ultrashort pulse laser sources that emit pulses with a fluence of up to 5 J and a duration of between 1 fs and 50 ps, ​​particularly preferably between 350 and 1000 fs. The pulse frequency is preferably between 10 kHz and 1000 kHz. By using ultrashort pulses of comparatively high energy, the material of the strip 22 is rapidly transformed from a solid to a gaseous state at the irradiated areas, preventing large-scale liquefaction. This significantly reduces the formation of irregular resolidification artifacts, which could negatively impact the nozzle shape and thus the function of the nozzle disk being produced.

[0096] Nevertheless, such artifacts cannot be completely avoided. For this reason, after all nozzle openings of all nozzle disks to be produced have been completely drilled in the laser drilling area 101, the material strip 95 passes through a cleaning section 94, in which any artifacts of melted and resolidified material are removed in an ultrasonic bath. Subsequently, in a finishing section 107, the nozzle disks are contoured, i.e., cut out along a desired contour. This usually has the basic shape of a circle. Depending on the application and attachment of the nozzle disk, however, further structures deviating from this basic shape can be formed or cut out. In the preferred embodiment of the inventive arrangement shown in Figure 1, this is done by a laser separator 96.As with the laser drilling 1a, 1b, several laser separators arranged next to each other transversely to the conveying direction V can also be present here.

[0097] The laser separator 96 comprises its own laser beam source 961 and laser optics 962, which focus the laser beam generated by the laser beam source in the form of the cutting laser beam 963 onto the surface of the material strip 95 supported by the base 964 and, using a laser scanner, guide it along the desired nozzle disk contour. The laser separator is controlled according to the program by the central control unit 41.

[0098] A camera system with image analysis (not shown) can enable the laser separator 96 to detect the areas with nozzle openings and to correctly align the cutting beam 963 relative to them.

[0099] Preferably, the nozzle disks are not completely separated from the rest of the material of the strip 95 by the laser separator 96, but rather only a predetermined breaking point is created and / or one, two or more, preferably regularly arranged, material bridges or webs remain. The separation then takes place in a punch 93 comprising a punch 931 and a die 932. A robot arm 99 then lifts the finished punched nozzle disks from the strip 95 into a container (not shown). The remnants of the raw material strip are subsequently shredded by a shredder 91. The punch 93 or a similar pressing tool arranged upstream or downstream of it in the travel direction V of the strip can additionally assume the function of imprinting a calotte- or dome-shaped region on the nozzle disks, in which the nozzle holes are arranged centrally or preferably concentrically.The curvature of this area is oriented in such a way that the tapering direction of the nozzle openings coincides with the direction of the curvature.

[0100] When used in nebulizers, the nozzle discs can be bonded to a vibration generator using an adhesive. This bond is advantageously improved if bonding openings are provided in the areas of the nozzle discs to be bonded, usually in the outer edge area. Depending on their size and number, these bonding openings can be created in the nozzle discs either by the laser drills 1a, 1b or the laser separator(s) 96.

[0101] List of reference symbols

[0102] 1, 1a, 1b laser drill

[0103] 2 Laser beam source

[0104] 21 Laser beam

[0105] 3 Laser optics

[0106] 31 beam-forming element

[0107] 310 diffractive beam splitter

[0108] 311 first imaging optics

[0109] 312 Mask

[0110] 313 second imaging optics

[0111] 33 Galvanoscanner housing

[0112] 331 Focusing optics

[0113] 332 Galvano scanner / 2-axis mirror

[0114] 32 drilling beams in the desired grid arrangement

[0115] 4 Control

[0116] 41 Control unit

[0117] 42 Input unit / PC

[0118] 43 control linesAsignals

[0119] 5 blank

[0120] 51 Nozzle disc area

[0121] 52, 52a, 52b nozzle opening

[0122] 520 central channel

[0123] 521 Nozzle inlet area

[0124] 522 horizontal material layer

[0125] 523 Nozzle outlet opening

[0126] 525 vertical material layer

[0127] 527 inclined material layer

[0128] 528 lowest horizontal material layer

[0129] G1 - G6 nozzle geometries

[0130] P beam power Beam width and beam speed

[0131] R Distance of the jet from the nozzle axis

[0132] D(R) Target drilling depth depending on R

[0133] 100 arrangement

[0134] 101 Laser drilling section

[0135] 104 Arrangement control

[0136] 105 Cleaning section

[0137] 107 Separation section

[0138] 9 Belt conveyor system

[0139] 90 material tape roll

[0140] 91 shredders

[0141] 92 Deflection / transport roller

[0142] 93 Punch

[0143] 931 stamps

[0144] 932 matrix

[0145] 95 material tape

[0146] 96 laser separator

[0147] 961 separator laser source

[0148] 962 separator optics

[0149] 963 Contour beam

[0150] 964 Underlay

[0151] 99 Robot arm

Claims

Patent claims 1. A device for producing a nozzle disk for use in a fluid transfer device, in particular a nebulizer, by means of laser processing, comprising: a laser beam source (2) for emitting a laser beam (21) to a laser optics (3) having a beam input for receiving the laser beam and a beam output, wherein the laser beam can be divided into a plurality of partial beams (32) arranged in a grid by means of a beam-shaping element (31) of the first laser optics (3), a controller (4) having a control unit (41) for controlling the laser beam source (2) and the laser optics (3), wherein the control unit (41) is prepared to control the laser beam source (2) and / or the laser optics (3) in such a way that the partial beams (32) generated by the laser optics (3) simultaneously form a first plurality of nozzle openings (52a,52b) in a first desired grid arrangement, completely or partially into the blank (5), wherein each of the nozzle openings (52a, 52b) has a desired nozzle geometry (G1, G2, G3) in which a taper factor, i.e. the ratio of an area of ​​a nozzle inlet opening (521) to an area of ​​a nozzle outlet opening (523), is 50 or more, in particular 100 or more.

2. Device according to claim 1, wherein the control unit (41) is further prepared to realize the desired nozzle geometry (G1, G2, G3) of the nozzle openings by varying a cross section of the partial jets (32) during the drilling process, in particular to realize a monotonously tapering nozzle geometry (G1, G2, G3) the jet cross section in During the drilling process, the jet cross-section is to be reduced in such a way that the jet cross-section at any time corresponds to the cross-section of the nozzle opening (52a, 52b) of the desired nozzle geometry (G1, G2, G3) at a drilling depth reached at that time.

3. Device according to one of the preceding claims, wherein the control unit (41) is further prepared to move each of the partial jets (32) in a pattern over the respective nozzle opening to be drilled, in particular such that material of the blank (5) to be removed is removed layer by layer, or in particular to realize a monotonically tapered nozzle geometry (G1, G2, G3), to move each of the partial jets from an outer edge of the inlet opening (521) on discrete concentric circles or spirally from the outside inwards to a central axis of the nozzle opening (52a, 52b) or vice versa, wherein the four variables average jet power of the partial jet (P), average jet cross-section (w), travel speed of the jet (w) and desired depth of the nozzle opening are selected at any time according to the desired nozzle geometry (G1, G2, G3) at the location of the current jet center point (D(R)) in such a way thatthat the first quantity is proportional to the product of the last three.

4. Device according to one of the preceding claims, wherein the control unit (41) is prepared to drill at least one nozzle opening, in particular all nozzle openings, such that a nozzle inlet opening has a diameter of 20 pm or more, in particular 25 pm or more and / or a nozzle outlet opening has a diameter of 3 micrometers or less, in particular 2.5 pm or less.

5. Device according to one of the preceding claims, wherein the beam-shaping element (31) of the laser optics (3) is reconfigurable so that the number and arrangement of the grid-shaped partial beams (32) can be selected by the control unit (41) according to a programming, and / or is a diffractive element and the division of the laser beam of the laser beam source (2) into a plurality of partial beams (32) takes place by diffraction.

6. Device according to one of the preceding claims, wherein the control unit (41) is further prepared to use the plurality of partial beams (32) to newly drill a second plurality of nozzle openings (52a, 52b) in a second desired grid arrangement in the region of the first nozzle disk (51) to be produced, and / or to further drill or finish drilling only partially completed nozzle openings of the first plurality of nozzle openings (52a, 52b), and in particular to reconfigure the beam-shaping element before drilling the second plurality of nozzle openings (52a, 52b) so that the second plurality of nozzle openings (52a, 52b) have a different grid geometry and / or a different outline, and / or to adjust an average beam power of the laser beam.

7. Device according to one of the preceding claims, wherein the laser optics (3) comprises a multi-beam laser scanner by means of which the plurality of partial beams (32) arranged in a grid shape can be displaced relative to a beam axis in two lateral directions perpendicular to one another and to the beam axis, and the control unit (41) is further prepared to re- relative to the first plurality by a vector contained in the unit cell of the grid arrangement of the first plurality of nozzle openings (52a, 52b) laterally offset.

8. Device according to one of the preceding claims, wherein the laser beam source (3) operates in a pulsed manner, in particular having a pulse duration between one femtosecond and one millisecond, preferably ultrashort pulse laser beam sources with a pulse duration between one femtosecond and one nanosecond, particularly preferably one or several femtoseconds.

9. Arrangement for producing nozzle disks for use in a fluid transfer device by means of laser processing, comprising: a device according to one of the preceding claims as a laser drill (1) with a first laser optics (3), and a belt conveyor system (9), which o comprises a raw material strip (95) provided on a roll (90) as a blank, which can be transported past the beam outlet of the laser optics (93) of the laser drill (91) in a conveying direction (V), and o can be controlled, in particular started and stopped, by a system control system (94).

10. Arrangement according to the preceding claim, characterized by a separation device (96) by means of which nozzle discs of a desired contour can be completely or partially separated from the raw material strip (95).

11. Arrangement according to the preceding claim, wherein the separation device is a laser separator (96) with a further laser optics (961), which in particular has its own laser beam source (962), wherein the further laser optics (961) is is prepared to generate a contour beam (963) which can be moved over the surface of the raw material strip (95) moving past a beam outlet of the second laser optics (961) in order to work out the desired contour of the nozzle disc (51) to be produced in the region of the nozzle disc (51) to be produced, or can be brought into a shape corresponding to the desired contour.

12. Arrangement according to the preceding claim, characterized by a camera system for detecting the areas of nozzle discs (51) to be produced based on the plurality of nozzle openings (52a, 52b) drilled by means of the laser drill (1), wherein the arrangement is prepared to transmit a position of the detected areas to the laser separator (96) for the purpose of correct alignment of the contour beam (963).

13. Arrangement according to one of the preceding arrangement claims, characterized in that the laser separator (96) is prepared not to completely sever the material of the raw material strip (95) along the contour, so that a nozzle disc (51) to be produced remains mechanically connected to the rest of the raw material strip after completion of the contouring, in particular via one or more webs, wherein in particular the separation is preferably carried out by means of a pressing tool (93) comprising a punch (931) and a die (932) following the laser separator (96) in the conveying direction (V) of the raw material strip (95).

14. Arrangement according to one of the preceding claims, characterized in that the further laser optics (961) of the laser separator (96) is fed by a pulsed laser beam source (962), which in particular generates pulses with a pulse duration between see a femtosecond and a millisecond, preferably ultrashort pulses with a pulse duration between a femtosecond and a nanosecond, particularly preferably one or a few picoseconds.

15. Arrangement according to one of the preceding claims, characterized by a cleaning section (94), which is arranged in particular between the laser drill (91) and the laser separator (96) and preferably comprises an ultrasonic bath (941).

16. Arrangement according to one of the preceding claims, characterized by a forming device (93) which is prepared to plastically deform the region in which the nozzle openings (52a, 52b) and / or the completely or partially separated nozzle disc (51) to be produced are located, in a direction perpendicular to the surface of the raw material strip, in particular to create a dome-shaped curved region, in particular such that the nozzle openings (52a, 52b) are located centrally therein.

17. Arrangement according to the preceding claim, characterized in that the forming device is a pressing tool (93) comprising a punch (931) and a die (932), which preferably simultaneously with the forming of the nozzle disc (51) completely separates it from the rest of the raw material strip (95).

18. Arrangement according to one of the two preceding claims, wherein the forming device is arranged in the transport direction of the raw material strip (95) after the laser drill (91) and immediately after a cleaning section or a separation device, in particular a laser separator (96).

19. A method for producing a nozzle disk comprising a plurality of nozzle holes for a fluid transport device, in particular a nebulizer, by means of the device (1) according to one of claims 1 - 9, wherein the surface of the blank (5) is subjected to the plurality of grid-shaped partial beams (32) generated by the laser optics (3) and as a result a first plurality of nozzle openings (52a, 52b) are drilled simultaneously in whole or in part in a desired grid arrangement in the region of the nozzle disks (51) to be produced, wherein each of the nozzle openings (52a, 52b) has a desired nozzle geometry (G1, G2, G3), in which in particular the ratio of an area of ​​a nozzle inlet opening to an area of ​​a nozzle outlet opening is 50 or more, in particular 100 or more.

20. Method according to the preceding claim, the desired nozzle geometry (G1, G2, G3) of the nozzle openings is realized by varying a cross-section of the partial jets during the drilling process, in particular to realize a monotonously tapered nozzle geometry (G1, G2, G3) the jet cross-section (w) is reduced during the drilling process so that at any time it corresponds to the cross-section of the nozzle opening according to the desired nozzle geometry (G1, G2, G3) in a drilling depth reached at that time, 21. Method according to claim 15, wherein each of the partial jets (32) is moved in a pattern over the opening to be drilled, in particular such that material of the blank (5) to be removed is removed layer by layer, or, in particular to realize a monotonously tapered nozzle geometry (G1, G2, G3), each of the partial jets is moved from an outer edge of the inlet opening (521) on discrete concentric circles or spirally from the outside to the inside to a central axis of the nozzle opening (52a, 52b) or vice versa, wherein the four The values ​​of average jet power of the partial jet (Pp), jet cross-section (w), travel speed of the jet (u) and desired depth of the nozzle opening according to the desired nozzle geometry (G1, G2, G3) at the location of the current jet center point (d(x)) can be selected at any time in such a way that the first value (Pp) is proportional to the product of the last three (wud(x)).

22. Method according to the preceding claim, characterized in that in the region of the nozzle disc (51) to be produced, a second plurality of nozzle openings (52b) arranged in a grid shape are drilled, which have a different grid arrangement and / or a different outline relative to the first plurality of nozzle openings (52a) arranged in a grid shape, and / or are offset by a lateral vector, wherein the first and the second plurality of grid-shaped nozzle openings can in particular overlap, i.e. can have one or more nozzle openings (52a, 52b) in common.

23. Method according to one of the preceding method claims, using an arrangement according to one of claims 10 - 14, wherein by means of the separation device, in particular the laser separator (96), the contour of the nozzle discs (51) to be produced is machined out of the raw material strip (95), and in this case in particular only a predetermined breaking point is created, and a removal of the nozzle discs takes place mechanically in a subsequent step, in particular by means of a pressing tool (93), wherein this is furthermore carried out in particular at a location different from the location of the laser processing.

24. Method according to one of the preceding method claims, characterized in that the nozzle disc (51) is arranged before or after it has been completely or partially separated from the rest of the raw material strip by means of a separation device, in particular a laser separator (96), it is deformed by means of a shaping device (93) in a direction perpendicular to the surface of the raw material strip (95), in particular in such a way that a dome-shaped curved region is created in which the nozzle openings (52a, 52b) created by the laser drill (91) are located, preferably centrally.

25. Nozzle disc for use in a fluid transfer device, in particular a nebulizer, comprising a plurality of nozzle openings (52a, 52b) in a grid arrangement, wherein each nozzle opening (52a, 52b) has a nozzle geometry in which a taper factor, i.e. the ratio of an area of ​​a nozzle inlet opening (521) to an area of ​​a nozzle outlet opening (523) is greater than one, characterized in that the taper factor is 50 or more, in particular 100 or more.

26. Nozzle disc according to the preceding claim, wherein the inlet opening (521) and the outlet opening (523) of at least one or part of the nozzle openings (52a, 52) are circular and the inlet opening (521) has a diameter of 20 pm or more, in particular 25 pm or more, and the outlet opening (523) has a diameter of 3 pm or less, in particular 2.5 pm or less.

Images