EP2953729B1 - Perforated plate for an application device and corresponding application and production method - Google Patents

Description

The invention relates to a perforated plate for an application device for applying a coating agent, such as, for example, a lacquer, a sealant, a functional layer or an adhesive or a release agent. The invention also relates to an application method in which such a perforated plate is used. In addition, the invention also comprises a novel production method for such a perforated plate.

To paint motor vehicle body parts, rotary atomizers are usually used, which atomize the paint to be applied by means of a rotating bell cup. These conventional rotary atomizers are well suited for full-surface painting of components, but the application of stripes or other patterns and also the coating of partial areas with them are problematic.

It is also known to use so-called drop generators for coating components, for example in DE 10 2010 019 612 A1 is described. The coating agent to be applied is passed through a perforated plate with numerous through-holes, whereby a jet of coating agent emerges from the individual through-holes of the perforated plate and breaks up into droplets, which then hit the component surface to be coated and form a coherent film of coating agent there. The problem with this known drop generator is the fact that the perforated plate has wetting surfaces at the hole openings which are partially wetted by the emerging coating agent during operation, which prevents the jet of coating agent from separating from the perforated plate.

Furthermore, with perforated plates according to the prior art, the problem arises that the required volume flow of coating agent is not achieved because the hole diameter is too small and the thickness of the perforated plate is too large to overcome the pressure loss that occurs with coating agents. If the thickness of the perforated plate is reduced, however, it loses its mechanical stability.

the end DE 691 23 224 T2 a nozzle plate for an inkjet printer is known, but this known nozzle plate cannot be used in the field of application technology.

Furthermore, reference should be made to the state of the art EP 0 928 637 A2 , DE 10 2004 030 640 A1 , DE 20 2011 000 324 U1 and DE 40 21 661 C2 .

Also disclosed JP 2003 165226 A a nozzle plate for an inkjet printer with a thickness of 50 µm - 90 µm.

Finally revealed EP 0 489 246 A2 a perforated plate according to the preamble of claim 1. However, this known perforated plate is designed for an inkjet printer and is therefore not suitable for producing a continuous coating agent film.

The invention is therefore based on the object of creating a correspondingly improved perforated plate and specifying a corresponding manufacturing method.

This object is achieved by a perforated plate according to the invention or by a manufacturing method according to the invention in accordance with the dependent claims.

The invention comprises the general technical teaching of providing the perforated plate on the downstream side with a three-dimensional structure which reduces the disruptive tendency to wetting and / or reduces the pressure loss when flowing through the through hole.

The invention initially comprises a perforated plate which is suitable for an application device for applying a coating agent, as is shown, for example, in FIG DE 10 2010 019 612 A1 is described. However, the invention is not limited to perforated plates for a specific type of application device, but also includes perforated plates which are suitable for other types of application devices. However, the perforated plate according to the invention is preferably suitable for an application device that applies a paint, a sealant, an adhesive or a release agent to a component, for example to a motor vehicle body component. However, with regard to the type of coating agent, the invention is not restricted to the aforementioned examples of coating agents, but can also be implemented with other types of coating agents. The functional layer category includes layers that result in surface functionalization, such as adhesion promoters, primers or layers to reduce transmission.

It should also be mentioned that the term “coating agent jet” used in the context of the invention includes both continuous coating agent jets and droplet jets.

In accordance with the prior art, the perforated plate according to the invention has a plurality of through holes which serve to pass the coating agent through, with a jet of coating agent emerging from the through holes which then strikes the component surface to be coated and there forms a coherent coating agent film.

The perforated plate according to the invention has a three-dimensional structure on its downstream side which reduces the wetting area at the opening of the hole and preferably reduces the pressure loss of the fluid flowing through.

When passing the coating agent through the through hole of the perforated plate, it must be taken into account that the downstream side of the perforated plate at the edge of the through hole forms a wetting surface that is wetted by the coating agent during operation, which makes detachment of the coating agent more difficult. To reduce this wetting area and thus to facilitate detachment of the coating agent from the perforated plate, provision is made for the through hole on the downstream side of the perforated plate to merge into a tube stub that protrudes from the downstream side of the perforated plate, so that only the end face of this Stub tube forms a disruptive wetting surface.

In addition, the disruptive wetting tendency can also be reduced in that the peripheral edge of the hole opening on the downstream side of the perforated plate has a structure which reduces the wetting tendency. Structures of this type are known per se from the prior art under the keyword “lotus effect” and can consist of microstructuring or nanostructuring, for example. Such a structuring can also improve the flushability of the component.

In the case of the above-mentioned pipe stub, in order to further reduce the disruptive wetting area, the pipe stub has an outer jacket surface which tapers, in particular conically, towards the free end of the pipe stub. Here, the wall thickness of the pipe stub decreases towards the free end of the pipe stub, so that the end face of the pipe stub at the mouth of the pipe stub is extremely small, which leads to a correspondingly small wetting area. For example, the wall thickness of the tube stub at its free end can be less than 100 μm, 50 μm, 10 μm or 5 μm.

Furthermore, within the scope of the invention there is the possibility that the tube stub has an orifice at its downstream free end which is inclined with respect to the longitudinal axis of the tube stub.

In order to achieve the smallest possible wetting surface of the pipe stub, it is preferably provided that the pipe stub has a wall thickness that is smaller than the inner diameter of the through hole. The wall thickness of the pipe stub is preferably in the range from 50% to 75% of the inner diameter of the through hole. In the preferred exemplary embodiment of the invention, the pipe stub has a wall thickness of at most 100 μm, 50 μm or 30 μm in order to form a correspondingly small wetting surface on the end face of the pipe stub.

Furthermore, in a preferred exemplary embodiment of the invention it is provided that the through hole has a hole opening on the upstream side of the perforated plate which is fluidically optimized. For example, this fluidic optimization can consist in a nozzle shape of the opening of the hole. However, it is also possible that the opening of the hole is only rounded in order to offer the lowest possible flow resistance.

In the same way, the opening of the through hole on the downstream side of the perforated plate can also be optimized in terms of flow, for example in the form of a nozzle or by rounding to reduce the flow resistance.

In the case of a nozzle-shaped configuration of the through hole, the through hole preferably forms a Laval nozzle, but other nozzle types are also possible.

The through hole itself preferably has an inner cross section which is constant along the longitudinal axis of the through hole, the inner cross section in the preferred exemplary embodiment of the invention being circular.

The inner cross-section can, however, also be similar to a rectangle or an oval.

However, within the scope of the invention, there is alternatively also the possibility that the inner cross section of the through hole changes along its longitudinal axis in order to form a nozzle shape, for example. Such a change in the internal cross-section of the through hole along its longitudinal axis is only possible to a limited extent or with certain restrictions in conventional manufacturing processes (e.g. drilling, milling). If, for example, the through hole between entry and exit is to be larger than the entry and exit itself, the limit of conventional manufacturing processes has been reached.

It should be mentioned here that the tube stub protrudes only slightly from the downstream surface of the perforated plate, for example with a length in the range of 25% -100%, 50% -100%, 25% -50% or 25% -75% of the Thickness of the perforated plate. Such a protruding length of the pipe stub is sufficient to limit the wetting to the face at the free end of the pipe stub.

The stub tube thus has a length between the downstream side of the perforated plate and the free end of the stub tube which is preferably greater than 10 μm, 20 μm, 50 μm or 100 μm and / or less than 1 mm, 500 μm, 200 μm or 100 µm.

It should also be mentioned that the perforated plate has a multiplicity of through holes, for example more than, 20, 50 or even more than 500 through holes.

The surface density of the through-holes, the distance between the immediately adjacent through-holes and the internal cross-section of the through-holes are dimensioned here in such a way that the coating agent jets emerging from the individual through-holes form a coherent coating agent film after striking the component.

It should also be mentioned that the through holes of the perforated plate have different internal cross sections. The same applies to the diameter of the through hole at the exit. The exit cross-section (diameter) determines the diameter of the coating agent jet (the droplets) and is therefore much more important than the inner diameter.

In addition, there is the possibility that the distance between the immediately adjacent through holes within the perforated plate is uniform.

Alternatively, however, there is also the possibility that the individual through holes are arranged at different distances from one another or are arranged in areas within which the distances between the through holes are the same, but differ from area to area.

In the preferred exemplary embodiment of the invention, the distance between the immediately adjacent through holes is at least equal to three, four or six times the inner diameter of the through holes.

It should also be mentioned that the through holes can be arranged, for example, at the corners of a polyhedron, such as, for example, at the corners of a triangle, a trapezoid or a rectangle.

The inside diameter of the individual through holes is preferably smaller than 0.2 mm, 100 μm, 50 μm or even smaller than 20 µm, which can hardly be achieved with machining processes.

The problem with the known drop generators is the manufacture of the perforated plate, since, for example, machining processes (e.g. drilling) only allow relatively large through holes with a diameter of at least 50 µm.

In addition, the aspect ratio of the inside diameter of the through holes on the one hand and the thickness of the perforated plate on the other hand is limited to an aspect ratio of 1:10, so that with a plate thickness of 0.5 mm an inside diameter of only at least 50 μm can be achieved.

Furthermore, the production of a large number of through holes in the perforated plate using machining processes (e.g. drilling, milling) is time-consuming and economically risky, since there is a risk that the tool (e.g. drill, milling cutter) will break off when the last through hole is made, causing the entire perforated plate becomes worthless.

It should also be taken into account that machining processes always produce burrs which impair the function of the perforated plate if they are not removed. In particular in the case of very small through holes, however, the removal of the burrs is difficult or even impossible from a manufacturing point of view.

It should also be taken into account that when the individual through-holes are made by piercing and punching processes, there is a displacement / deformation of material around the respective through-hole takes place around, which leads to a corresponding deformation of the perforated plate.

Through holes with an inside diameter of less than 50 μm can therefore only be produced with a high expenditure of time by laser processing with ultrashort pulse lasers.

The disadvantage of the known perforated plates for application devices (e.g. drop generators) is the problematic production of very small through holes and very small three-dimensional structures in particular.

The invention therefore preferably provides that the perforated plate is produced by etching technology, in particular by dry etching or wet etching. In this case, the through holes can be produced by an etching attack on the perforated plate, the other areas of the perforated plate between the through holes being protected by an etching stop and therefore not being removed. Etching production processes are known per se, for example, from the field of semiconductor technology and therefore do not need to be described in more detail. The term used in the context of the invention of an etching-technical production of the perforated plate means that at least the through-holes are made by etching, while the perforated plate itself (i.e. initially without the through-holes) can be provided as a blank.

One advantage of producing the perforated plate by means of etching is the possibility of economical production of a perforated plate with a large number of through holes, since the production costs are independent of the number of through holes.

A further advantage of the etching technology production of the perforated plate is that no burrs arise due to the production process, so that there is no need for costly post-processing to remove the burrs.

In addition, no chips or other processing residues (e.g. drilling emulsions) that could contaminate the through holes are created or left in an etching process.

It should also be mentioned as an advantage that the same surface quality can be achieved in the case of an etching technique on the outer surface of the bores as in the case of more easily accessible surfaces.

Another advantage that should be mentioned is that during the etching process there is no temperature effect on the component that could change the material structure. Furthermore, no mechanical stress is exerted on the component, which could cause stresses in the component.

Finally, an etching technique of the perforated plate enables an exact parallelism of the through-holes, because all through-holes are made simultaneously with the same process and because, in contrast to drilling the through-holes, no drill can run. If, for example, exposure is carried out completely vertically in a first process step of the etching-technical production, then all geometries are etched in the same way, since the etching attack can be controlled extremely evenly with gas, for example.

In a preferred exemplary embodiment of the invention, the perforated plate consists at least partially of a semiconductor material such as silicon, silicon dioxide, silicon carbide, gallium, gallium arsenide or indium phosphide. However, with regard to the semiconductor material, the invention is not restricted to the aforementioned examples of semiconductor materials. In addition, within the scope of the invention, the perforated plate can also consist of a different material that allows production by etching technology. For example, iron metals (e.g. steels, stainless steels and other alloys), non-ferrous metals (e.g. aluminum, molybdenum, tungsten, gold, silver, tin, zinc, titanium, copper and copper alloys), semi-metals (e.g. tellurium, boron), Transition metals (e.g. nickel and cobalt materials) and ceramics (e.g. zirconium oxide, aluminum oxide) should be mentioned.

It has already been mentioned briefly above that the etching technology production of the perforated plate offers the advantage that the through-bores can be aligned exactly in parallel. In the preferred embodiment of the invention, the through-bores with their longitudinal axes therefore have an extremely small angular deviation with one another or relative to the surface normal of the perforated plate, this angular deviation preferably being less than 1 °, 0.5 °, 0.01 ° or even less than 0.001 °.

However, with regard to the production of the perforated plate, the invention is not limited to etching production processes, but can also be implemented using conventional production processes. For example, machining processes (for example drilling, milling), punching or laser drilling can also be used.

In addition, a combination of machining manufacturing processes and etching manufacturing processes is also possible.

For example, a blank of the perforated plate can first be machined, whereupon the through holes are made by etching.

Alternatively, there is also the possibility that the perforated plate is first produced by etching and then subsequently machined.

Furthermore, within the scope of the invention there is the possibility that a coating can be applied to one or both sides of the perforated plate, such as a corrosion protection layer or an electrically conductive layer. In addition, the coating can also be part of a sensor or a logic circuit.

In a variant of the invention, the perforated plate has an essentially constant thickness over its entire surface.

In another variant of the invention, however, the perforated plate has an outer edge with a greater thickness and a central area with the through holes, the thickness of the perforated plate in the area with the through holes being smaller than at the edge. This reduction in the thickness in the region of the through holes is advantageous because it reduces the flow resistance of the through holes. The thickness of the perforated plate in the area of the through holes is therefore less than 1 mm and preferably even less than 0.5 mm or even less than 0.3 mm. Furthermore, within the scope of the invention there is the possibility that the perforated plate has at least one reinforcement strip for mechanical reinforcement, the perforated plate having a smaller thickness in the area of the through holes than in the area of the reinforcement strip. For example, the perforated plate on the edge or on the reinforcement strip can have a thickness of less than 2 mm, 1 mm or 0.7 mm.

In addition to the perforated plate according to the invention described above, the invention also claims protection for a complete application device with such a perforated plate.

The perforated plate can, for example, be part of a nozzle, a nozzle insert, a guide air ring, a diaphragm, a mixer, a sieve, a valve needle or a needle seat.

In addition, the invention also claims protection for an application method that uses an application device with such a perforated plate.

Finally, the invention also claims protection for a corresponding manufacturing method for manufacturing such a perforated plate.

For example, the perforated plate can be processed by etching technology on one or both sides here.

It should also be mentioned in this connection that, for example, dry etching or wet etching is possible.

Figur 1

eine Aufsicht auf eine nicht erfindungsgemäße Lochplatte,

Figur 2

eine Querschnittsansicht durch ein Durchgangsloch der Lochplatte aus Figur 1,

Figur 3

eine Abwandlung von Figur 2,

Figur 4A

eine Querschnittsansicht durch ein Durchgangsloch der Lochplatte in einer anderen nicht erfindungsgemäßen Variante,

Figur 4B

die Querschnittsansicht aus Figur 4A mit Beschichtungsmittel in dem Durchgangsloch,

Figur 5A

eine erfindungsgemäße Abwandlung von Figur 4A mit einem zusätzlichen Rohrstummel zur Verringerung der Benetzungsfläche,

Figur 5B

die Querschnittsansicht aus Figur 5A mit Beschichtungsmittel in dem Durchgangsloch,

Figur 6A

eine erfindungsgemäße Abwandlung von Figur 5A mit einem konisch zulaufenden Rohrstummel,

Figur 6B

eine erfindungsgemäße Abwandlung von Figur 6A mit einer geneigten Mündungsöffnung des Rohrstummels,

Figur 6C

eine erfindungsgemäße Abwandlung von Figur 5A mit einer geneigten Mündungsöffnung des Rohrstummels,

Figur 7A

eine schematische Querschnittsansicht durch eine nicht erfindungsgemäße Lochplatte mit einem verstärken Rand und einem dünneren mittigen Bereich mit den Durchgangslöchern,

Figur 7B

eine Abwandlung von Figur 7A,

Figur 8A

eine schematische Querschnittsansicht durch eine nicht erfindungsgemäße Lochplatte mit Verstärkungsstreifen,

Figur 8B

eine Aufsicht auf die Lochplatte aus Figur 8A,

Figur 9

einen Einsatz mit mehreren Lochplatten,

Figur 10

ein erfindungsgemäßes Applikationsgerät mit einer erfindungsgemäßen Lochplatte,

Figur 11

eine nicht erfindungsgemäße Abwandlung von Figur 2.

Other advantageous developments of the invention are characterized in the subclaims or are summarized below explained in more detail with the description of the preferred exemplary embodiments of the invention with reference to the figures. Show it:

Figure 1

a plan view of a perforated plate not according to the invention,

Figure 2

a cross-sectional view through a through hole of the perforated plate Figure 1 ,

Figure 3

a variation of Figure 2 ,

Figure 4A

a cross-sectional view through a through hole of the perforated plate in another variant not according to the invention,

Figure 4B

the cross-sectional view Figure 4A with coating agent in the through hole,

Figure 5A

an inventive modification of Figure 4A with an additional pipe stub to reduce the wetting area,

Figure 5B

the cross-sectional view Figure 5A with coating agent in the through hole,

Figure 6A

an inventive modification of Figure 5A with a conical pipe stub,

Figure 6B

an inventive modification of Figure 6A with an inclined mouth of the pipe stub,

Figure 6C

an inventive modification of Figure 5A with an inclined mouth of the pipe stub,

Figure 7A

a schematic cross-sectional view through a perforated plate not according to the invention with a reinforced edge and a thinner central area with the through holes,

Figure 7B

a variation of Figure 7A ,

Figure 8A

a schematic cross-sectional view through a perforated plate not according to the invention with reinforcing strips,

Figure 8B

a plan view of the perforated plate Figure 8A ,

Figure 9

an insert with several perforated plates,

Figure 10

an application device according to the invention with a perforated plate according to the invention,

Figure 11

a non-inventive modification of Figure 2 .

Figure 1 shows a plan view of a perforated plate 1, not according to the invention, which can be used, for example, in a drop generator. With regard to the design details of the drop generator, see also DE 10 2010 019 612 A1 referenced.

The perforated plate 1 has a multiplicity of through holes 2 which are arranged in the perforated plate 1, the through holes 2 in the perforated plate 1 being arranged equidistantly and in the form of a matrix.

The perforated plate 1 according to the invention is distinguished by an etching technique.

Figure 2 shows a cross-sectional view through the perforated plate 1 in the area of one of the through-holes 2, the arrow in the cross-sectional view indicating the direction of flow of the coating agent through the through-hole 2. From the cross-sectional view it can be seen that the through-hole 2 has a flow-optimized hole opening 3, as a result of which the flow resistance of the through-hole 2 is reduced.

In addition, on the downstream side on the peripheral edge of the through holes 2, the perforated plate 1 has a structuring which reduces the tendency to wetting.

In the embodiment according to Figure 3 In addition to the flow-optimized hole opening 3, the through-hole 2 also has a flow-optimized hole opening 4, so that the through-hole 2 forms a Laval nozzle.

the Figures 4A and 4B show an alternative cross-sectional view through the perforated plate 1 in the area of a through hole 2, wherein Figure 4A shows the through hole 2 without a coating agent, whereas in FIG Figure 4B a coating agent 5 is shown.

It can be seen from this that the coating agent 5 wets a wetting surface 6 on the downstream surface of the perforated plate 1, which makes a jet-shaped detachment of the coating agent 5 from the perforated plate 1 difficult despite the structuring.

the Figures 5A and 5B show a preferred embodiment of the invention with a further reduced tendency to wetting. For this purpose, the perforated plate 1 has a tubular stub 7 on the circumferential edge of the individual through holes 2, the through hole 2 merging into the tubular stub 7 so that the end face of the tubular stub 7 forms a wetting surface 8 at the free end of the tubular stub 7. The wetting surface 8 is therefore limited to the free end face of the pipe stub 7 and is therefore significantly smaller than the wetting surface 6 according to FIG Figure 4A . This facilitates the detachment of the coating agent 5 from the perforated plate 1.

The tubular stub 7 protrudes from the downstream surface of the perforated plate 1 with a length L = 100 μm.

Figure 6A shows a modification of Figure 5A , wherein the outer jacket surface of the tubular stub 7 tapers conically towards the free end of the tubular stub 7, so that the wetting surface at the free end of the tubular stub 7 is minimal.

Figure 6B shows a modification of Figure 6A , wherein the mouth opening of the tubular stub 7 is inclined with respect to the longitudinal axis of the through hole 2.

Figure 6C shows a modification of Figure 5A , wherein the mouth opening of the tubular stub 7 is inclined with respect to the longitudinal axis of the through hole.

Figure 7A shows a schematic cross-sectional view through a perforated plate 1 not according to the invention, which partially corresponds to the perforated plates described above, so that to avoid repetitions on the above Description is referred to, the same reference numerals being used for corresponding details.

A special feature of this exemplary embodiment is that the perforated plate 1 has a relatively thick edge 9 on the outside and a thinner area 10 with the through holes 2 in the middle. The thick edge 9 of the perforated plate 1 ensures sufficient mechanical stability, while the reduction in thickness in the area 10 with the through holes 2 ensures that the through holes 2 offer only a relatively low flow resistance.

Figure 7B shows a modification of FIG. 7A, not according to the invention, so that to avoid repetition, reference is made to the description Figure 7A is referred to, the same reference numerals being used for corresponding details.

A special feature of this exemplary embodiment is that the area 10 is only reduced in thickness on one side.

the Figures 8A and 8B show a perforated plate 1 not according to the invention, which partly coincide with the exemplary embodiments described above, so that reference is made to the above description to avoid repetition, the same reference symbols being used for corresponding details.

A special feature of this exemplary embodiment is that, in addition to the edge 9 of the perforated plate 1, thicker reinforcement strips 11 are also provided.

The sharp edges and corners shown in the figures are only shown by way of example and can advantageously also be rounded off in order to make them more fluid in terms of flow or to achieve better flushability.

Figure 9 shows a holder 12 with three perforated plates 13, 14, 15 which directly adjoin one another.

Also shows Figure 10 In a greatly simplified schematic representation, an application device with a perforated plate 1 according to the invention for coating a component 16 (for example a motor vehicle body component).

Coating agent jets 17 emerge from the individual through-holes 2 of the perforated plate 1, as they do themselves DE 10 2010 019 612 A1 is known. After striking the surface of the component 16, these coating agent jets 17 form a coherent coating agent film on the surface of the component 16.

The drawing also shows an applicator 18 connected to the perforated plate 1 and application technology 19 which is connected to the applicator 18 by lines shown schematically.

List of reference symbols:

1

Perforated plate

2

Through holes

3

Opening of the hole

4th

Hole outlet

5

Coating agents

6th

Wetting surface

7th

Pipe stub

8th

Wetting surface

9

edge

10

Area with through holes

11

Reinforcement strips

12th

bracket

13th

Perforated plate

14th

Perforated plate

15th

Perforated plate

16

Component

17th

Coating agent blasting

18th

Applicator

19th

Application technology

20th

Cylindrical area of the through hole

21

Conical area of the through hole

d1

Inner diameter of the cylindrical area

d2

Inner diameter of the conical area

Claims (14)

1. A perforated plate (1) for an application device (18, 19) for the application of a fluid, in particular a coating agent, a paint, a sealant, a glue, a functional layer or a separating agent, to a component (16), in particular to a motor vehicle body component, with

   a) a plurality of through-holes (2) for passing the coating agent through, each with

   a1) a hole inlet opening (3) on the side of the perforated plate (1) that is located upstream, and

   a2) a hole exit opening (4) on the side of the perforated plate (1) that is located downstream, and

   a3) a three-dimensional structuring on the side of the perforated plate (1) that is located downstream,

   a4) wherein the structuring comprises a pipe stub (7) which protrudes from the side of the perforated plate (1) that is located downstream and into which the through-hole (2) transitions, in order to reduce a wetting surface (6, 8) at the hole exit opening (4),

   b) wherein the surface density of the through-holes (2), the distance between the through-holes (2) and the internal cross-section of the through-holes (2) are dimensioned such that the coating-agent jets (17) emerging from the through-holes (2), after impinging on the component (16), form a coherent coating-agent film, characterised in

   c) that the through-holes (2) have different internal cross-sections, and

   d) that the perforated plate (1) in the region with the through-holes has a thickness of less than 1 mm.
2. A perforated plate (1) according to Claim 1, characterised in

   a) that inlet openings (3) are each nozzle-shaped, and/or

   b) that the through-holes (2) each have an internal cross-section which is substantially constant along its longitudinal axis, and/or

   c) that the perforated plate (1) comprises more than 10, 20, 50, 100 or 500 through-holes.
3. A perforated plate according to one of the preceding claims, characterised in

   a) that the hole inlet openings (3) each have a larger cross-section than the hole exit opening (4), and/or

   b) that the through-holes (2) at the hole inlet opening (3) each have a cylindrical portion, and at the hole exit opening (4) a portion which tapers conically in the direction of flow.
4. A perforated plate (1) according to any of the preceding claims, characterised by

   a) identical distances between the directly neighbouring through-holes (2) or

   b) different distances between the directly neighbouring through-holes (2).
5. A perforated plate (1) according to one of the preceding claims, characterised in

   a) that the distance between the directly neighbouring through-holes (2) is at least equal to 3 times, 4 times or 6 times the internal diameter of the through-holes (2), and/or

   b) that the through-holes (2) are arranged at the corners of a polyhedron, in particular at the corners of a triangle, a trapezium or a rectangle, and/or

   c) that the through-holes (2) each have an internal diameter of at most 0.2 mm, 100 µm, 50 µm or 20 µm, and/or

   d) that the through-holes (2) are arranged with their longitudinal axes parallel relative to each other and/or have an angular deviation of less than 1°, 0.5°, 0.01° or 0.001° relative to the surface normal of the perforated plate (1), and/or

   e) the through-holes (2) in the perforated plate (1) are produced at least partially by one of the following production methods, or by a combination of at least two of the following production methods:

   e1) etching production methods, in particular dry etching or wet etching,

   e2) cutting production methods, in particular drilling or milling,

   e3) punching,

   e4) laser drilling.
6. A perforated plate (1) according to one of the preceding claims, characterised in

   a) that the perforated plate (1) consists at least partially of a semiconductor material, in particular of one of the following materials:

   a1) silicon,

   a2) silicon dioxide,

   a3) silicon carbide,

   a4) gallium,

   a5) gallium arsenide,

   a6) indium phosphide, or

   b) that the perforated plate (1) consists at least partially of a ferrous metal, in particular of one of the following materials:

   b1) steel,

   b2) high-grade steel,

   b3) steel alloy, or

   c) that the perforated plate (1) consists at least partially of a non-ferrous metal, in particular of one of the following materials:

   c1) aluminium,

   c2) gold

   c3) silver

   c4) tin,

   c5) zinc,

   c6) titanium,

   c7) copper,

   c8) copper alloy, or

   d) that the perforated plate (1) consists at least partially of a semimetal, in particular of one of the following materials:

   d1) tellurium,

   d2) boron, or

   e) that the perforated plate (1) consists at least partially of a transition metal, in particular of one of the following materials:

   e1) nickel,

   e2) cobalt, or

   f) that the perforated plate (1) consists at least partially of ceramic, in particular of one of the following materials:

   f1) zirconium oxide,

   f2) aluminium oxide and/or

   g) that the perforate plate (1) comprises a coating on one side or on both sides, the coating

   g1) forming protection against corrosion, and/or

   g2) being electrically conductive, and/or

   g3) being a constituent of a sensor, and/or

   g4) being a constituent of a logic circuit.
7. A perforated plate (1) according to one of the preceding claims, characterised in

   a) that the perforated plate (1) has a substantially constant thickness, or

   b) that the perforated plate (1) at the edge (9) has a greater thickness than in a central region (10) with the through-holes, and/or

   c) that the perforated plate (1) in the region (10) with the through-holes has a thickness of less than 1 mm, 0.5 mm or 0.3 mm, and/or

   d) that the perforated plate (1) for mechanical reinforcement has at least one reinforcing strip (11), the perforated plate (1) in the region (10) of the through-holes having a lesser thickness than in the region of the reinforcing strip, and/or

   e) that the perforated plate (1) at the edge (9) and/or at the reinforcing strip (11) has a thickness of less than 2 mm, 1 mm or 0.7 mm.
8. An application device (18, 19) for the application of a fluid, in particular a coating agent, in particular a paint, a sealant, a glue, a functional layer or a separating agent, to a component (16), in particular to a motor vehicle body component, with at least one perforated plate (1) according to one of the preceding claims.
9. An application device (18, 19) according to Claim 8, characterised in that the perforated plate (1) is a constituent of one of the following components:

   a) nozzle,

   b) nozzle insert,

   c) shaping air ring,

   d) diaphragm,

   e) mixer,

   f) screen,

   g) valve needle,

   h) needle seat.
10. An application method for the application of a fluid, in particular a coating agent, in particular a paint, a sealant, a glue, a functional layer or a separating agent, to a component (16), wherein the coating agent is passed through at least one through-hole (2) in a perforated plate (1) and after emerging from the through-hole (2) forms a coating-agent jet (17) which impinges on the component (16) to be coated, characterised in that the perforated plate (1) is formed in accordance with one of Claims 1 to 7.
11. An application method according to Claim 10, characterised in

    a) that stripes and/or patterns of the coating agent are applied to the component (16) with the perforated plate (1), or

    b) that the component (16) is coated with the coating agent over its full surface using the perforated plate (1) .
12. A production method for a perforated plate (1) for an application device (18, 19) for the application of a coating agent, in particular for a perforated plate (1) according to one of Claims 1 to 7, with the following steps:

    a) producing a plurality of through-holes (2) for passing the coating agent through into the perforated plate (1), so that a hole exit opening (4) of the through-holes (2) on the side of the perforated plate (1) that is located downstream each forms a wetting surface which can be wetted by the coating agent during operation,

    b) producing a three-dimensional structuring on the side of the perforated plate (1) that is located downstream,

    c) producing a pipe stub (7) on the side of the perforated plate (1) that is located downstream, in order to reduce the wetting surface (6, 8) at the hole exit opening (4), the pipe stub (7) protruding from the side of the perforated plate (1) that is located downstream and the through-hole (2) transitioning into the pipe stub (7),
    characterised in

    d) that the surface density of the through-holes (2), the distance between the through-holes (2) and the internal cross-section of the through-holes (2) are dimensioned such that the coating-agent jets (17) emerging from the through-holes (2), after impinging on the component (16), form a coherent coating-agent film,

    e) that the through-holes (2) have different internal cross-sections, and

    f) that the perforated plate (1) in the region with the through-holes has a thickness of less than 1 mm.
13. A production method according to Claim 12, characterised in that the through-hole (2) is produced at least partially by one of the following production methods or by a combination of the following production methods:

    a) etching production methods, in particular by dry etching or wet etching,

    b) cutting production methods, in particular drilling or milling,

    c) punching,

    d) laser drilling.
14. A production method according to Claim 13, characterised in

    a) that the perforated plate (1) is processed by etching on both sides, or

    b) that the perforated plate (1) is processed by etching only on one side.

Images