EP1287200A1

EP1287200A1 - Influencing the profile of the properties of a web by means of an acoustic field

Info

Publication number: EP1287200A1
Application number: EP01943037A
Authority: EP
Inventors: Dieter Ronnenberg
Original assignee: Individual
Current assignee: Ronnenberg Dieter
Priority date: 2000-05-08
Filing date: 2001-05-08
Publication date: 2003-03-05
Also published as: DE10022110B4; AU2001265769A1; EP2345761A2; WO2001086061A1; US20060157213A1; DE10022110A1; EP2345761A3; US20030188842A1

Abstract

The invention relates to a method and a device for the processing of a fibre web or a suspension layer in a paper-, cardboard- or carding-machine or a size press for influencing the profile of the properties of a web by means of at least one sectional, directed acoustic field. In other words, the acoustic field is narrower than the width of the fibre web, or the suspension layer and the acoustic field affects components of the fibre web, or suspension layer at a defined angle. The profiles of the properties of a web influenced by acoustic fields are lamination, spatial orientation, fibre orientation, dry content, breaking length ratio, flocculation and colour coat depth. Furthermore the introduction of a signature mark into the fibre web or suspension layer is possible.

Description

Influencing a web property profile by means of at least one sound field

description

The invention relates to a method and a device for processing a fibrous web or a suspension layer in a paper, cardboard or coating machine or size press for influencing a web property profile and the paper or cardboard obtained in this way according to the preambles of claims 1, 23 and 25.

Since the present invention can be used both for paper machines and for cardboard machines, for the sake of language simplification only paper machines will be referred to below. The transition from a suspension layer to a fibrous web in the form of a paper machine is referred to by experts as the so-called immobility point. This is the point from which the fibers themselves - according to the previous opinion of the experts - no longer change their position in the fibrous web. However, because this point cannot be determined precisely locally and because the immobility point can be moved in the direction of the press section by means of the present invention, only one fibrous web is referred to below for reasons of simplification. This language agreement apply of course not for the claims and the summary of these documents.

A wide variety of paper machines and their assemblies are known from the prior art. The documents EP 0489094 AI and EP 0627523 AI should be mentioned as examples. Shapes are specifically described in these documents. These formers have in common that a machine-wide suspension jet coming from a headbox is injected between two sieve belts of the former. Various dewatering elements then take over the dewatering of the suspension jet in the former, so that at the end of the former a coherent fibrous web is formed. However, this fibrous web still has such a low strength that a take-off suction roll of the subsequent press section must carefully take over the web without a so-called "free pull".

The two most important properties of a fibrous web at the end of the paper machine are a uniform basis weight and a fiber orientation cross profile. Since the invention of the sectoral (i.e. zoned working width),

Regarding the density of the headbox, these cross profiles can be set independently of one another in the headbox. This is published in the special edition p2971 "Fiber Orientation Cross Profile" by Voith Sulzer Paper Technology, among others. Nevertheless, there are also when using this Headboxes often have a fiber orientation cross profile that is faulty.

With headboxes that are not sectionally density controlled, the approximate correct setting of the desired basis weight and fiber orientation cross profiles is even more difficult, as any expert knows from experience.

The dewatering of a fibrous web in the former takes place essentially by means of a forming roller and machine-wide subsequent dewatering strips arranged transversely to the direction of wire travel. In some cases, however, dewatering is also carried out using machine-wide drag blades, foils or so-called skimmers. In the case of Fourdrinier paper machines, register rollers were previously used for this. Despite the invention of the sectional, material density-controlled headbox, there is still a crucial problem in papermaking: because the drainage distance from the headbox nozzle to the immobility point is several meters and because the suspension jet is highly turbulent, the fiber orientation experiences during dewatering in the former Significant disturbances, which in turn lead to the deterioration of the fiber orientation cross profile.

Another disadvantage in the prior art is that the fiber orientation cross profile in the former only has a slight influence can be. This influencing takes place, for example, by - viewed across the width of the machine - different pressing of the drainage elements. Since in the prior art the dewatering elements are essentially rigid elements, even if the dewatering elements are pressed against the screen in a punctiform manner, neighboring regions of this point are also pressed. This results in a quasi "radiating" effect of the drainage elements. Overall, the actually pressed area of the drainage element can then be up to 1 meter. This different pressing of the dewatering elements then leads to transverse flows (ie transverse to the direction of wire travel) within the fibrous web. This again brings the disadvantages - as described in the cited document p2971 - of the dependent interaction between the basis weight profile, fiber orientation profile and dry content cross profile.

Every time the screen of a former runs over a dewatering element, pressure impulses are created on the fibrous web. This is described, for example, in the company publication p3025e "High Technology Components for Cost Effective Paper Mashine Upgrading" from Voith Sulzer Paper Technology, pages 4 and 5. Another disadvantage in the prior art consists in the fact that the number of impulses coinciding with the number of dewatering elements, and thereby the number of pulses is limited ^'. In addition, the impulse itself a technological disadvantage: It is known from Fourier mathematics that an impulse can be simulated by superposition of various sine and cosine functions, which are integer multiples of a basic frequency. The shape of the pulse is determined by the hydrodynamic conditions between the drainage element and the sieve. If these hydrodynamic conditions change slightly (for example due to a change in the water wedge between the drainage element and sieve), it may be the case that the frequency component responsible for better fiber orientation (or retention) is no longer available. Changes in the shape of the pulse primarily affect the higher frequency components, with these higher frequencies being particularly high in energy and therefore advantageous.

Another disadvantage in the prior art is that the pulses are essentially only perpendicular to the fibrous web or the screen. In addition, the impulses - viewed across the width of the machine - can only be partially influenced by the different pressing of the drainage elements, which again brings with it the disadvantages of the "radiating effect" mentioned above.

It is therefore an object of the invention to find a method, an apparatus and a paper which reduces or even avoids the mentioned disadvantages of the prior art.

The object is achieved by the characterizing features of claims 1, 23 and 25. The subclaims describe advantageous embodiments of the invention.

As already described, after leaving the suspension jet from the headbox there is only a slight and inadequate possibility of influencing the basis weight and / or fiber orientation cross profile through the drainage elements. Generally, the problem is that the fibrous web is sandwiched between two screens. Since the sieves move, you cannot "reach through" them, for example to influence the fiber orientation. The leader and drive-side gap between the sieves also offers no possibility - for example on the fiber orientation - of influencing, since otherwise from this gap, at least half the machine width would have to be knitted into the fiber web. With machine widths of up to 10 meters and a screen spacing of just a few millimeters, this cannot be managed from today's perspective, especially since the areas of the fibrous web that are closer to the driver or drive side block access to areas further to the center of the machine. The inventor therefore searched for a construction element that would allow him to "reach through" at least one of the screens. This tool should be able to work through the moving meshes into the area between the screens without being placed in the mesh itself. Since such a fine, physical tool is out of the question for rough use within a paper machine, the inventor came up with the idea of sending a directed energy through the sieve mesh. Since open electrical energy is not practical because of the moisture, the decision was made in favor of sound. Although the wavefronts of the sound waves are destroyed by the threads of the sieve, elementary waves form in the meshes of the sieve, which - according to Huyghens' principle - but after penetrating the meshes, again interfere with each other to form wavefronts.

Influencing the fibrous web by means of a sound field brings an elementary advantage over the prior art: the sound field can be placed directly at the point of the fibrous web to be influenced, on the side of the screen facing away from the fibrous web. The distance to the fibers between the screen surfaces is less than one millimeter (with a screen thickness of 0.7 millimeters, for example) and not several meters as before. As has been shown, the sieve itself does not pose any significant obstacle Another advantage of the sound field compared to the drainage strips is that there is no "radiating effect" transverse to the machine direction.

Kundt's dust figures and the Chladnian sound figures are known from physics. In these figures, particles are aligned by means of vibrations on a horizontal plane (particle accumulations in the vertical can be neglected because of the relation to the horizontal plane). Alignment of the particles around one of their body axes - as e.g. would be necessary for influencing the fiber orientation - is however not known from these figures. Furthermore, the shapes of the above-mentioned figures cannot be used for influencing the fibrous web, because homogeneity in the plane is expected from a fibrous web.

Since a single sound source would not be sufficient at today's fiber web widths of up to 10 meters, the use of at least two point sources in relation to the machine width would result in interference hyperbolas, which would make a homogeneous sound field impossible.

The question then arose as to what the shape of a sound field must be in order to influence fiber orientation, for example can. There was also the question: does a sound field penetrating the fibrous web shake the fibers just like the feathers of a pillow are shaken, or do the fibers experience a certain orientation through the direction of the sound field? Through the article "The Ultrasonic Field as a Cold Gas Trap" from "Spectrum of Science" from January 2000 (German edition), the inventor learned about the possibility of levitating ice crystals using an ultrasonic field. In the aspect that particles can be made to float with the aid of this device, the inventor saw a partial solution to the particles of the Kundt see dust figures or the Chladnian sound figures lying on one level. Ultrasound is not absolutely necessary for the "cold gas trap", but it offered itself as an aid because it is particularly energy-intensive. While studying basic literature (physics and technology of ultrasound, author Heinrich Kuttruff, S. Hirzel Verlag, Stuttgart, edition 1988), the inventor discovered on page 169 a treatise on the so-called Pohlman cell. This Pohlman cell (quotation) "... is a flat vessel with transparent walls; the wall facing the incident sound is a thin film and thus permeable to sound. In this cell there is a liquid in which numerous small and thin metals are found - Papers are suspended. When at rest, these papers are randomly oriented, but if they are hit by a sound wave, place them it is perpendicular to the direction of sound incidence ... ". Here too, ultrasound is not absolutely necessary, but is helpful because of its high energy density. The described alignment of the platelets is due to the" 2nd order effects "known from physics.

For production-related reasons, the main direction of the fibers in a paper machine is usually desired in the machine running direction, because this increases the tensile strength of the paper in this direction and thus reduces the risk of web breaks. If you want to use the effect of the Pohlman cell for fiber alignment (fibers = wood pulp and pulp), for example in the machine direction, the direction of propagation of the sound field must be aligned transversely to the machine direction and at the same time as acute as possible to the screen. As a result of this alignment of the sound field, the fibers of the fibrous web align - at least in part - in a plane which on the one hand points in the machine running direction and on the other is at an angle between the sieves. In this plane, however, in extreme cases the fibers can point with one end to one sieve and with their other end to the other sieve and are therefore not in the machine running direction. That is why they do not initially contribute to the increase in strength - the so-called tear length. Here, however, the inventor recognized that the gradual approach of the screens in the further course of the drainage and the associated drainage flow towards the outer surface of the sieve, these fibers are folded in or against the machine direction - while maintaining their position in the plane generated by the sound field.

Even if fibers move together with the sieves - while moving past the sound field - possibly only imperceptibly in the plane perpendicular to the direction of propagation of the sound field, the fibers still experience an angular momentum which gives them the desired rotation even after leaving the sound field can be carried out further.

For completeness, it should be mentioned that in the area of the former some aware of the main fiber direction - e.g. in the edge areas of the fibrous web - at an acute angle to the machine direction. The further dewatering and drying process of the fibrous web causes the fibers to shrink, for example, so that at the end of the paper machine the main direction of the fibers is essentially parallel to the machine direction. The desired fiber orientation cross profile at the end of the former is by no means a graph that is identical to the zero line.

In addition to the possibility of aligning fibers using a sound field, there is also the alternative of exposing the fibers to two sound fields. These two Sound fields either act on the fibers one after the other, as viewed in the machine running direction, or these sound fields simultaneously hit the fibers of a fibrous web width section (sectional width). It is important with this idea of the invention that the fibers are ultimately not leaflets - as in the Pohlman cell cited. The fibers are more comparable to rod-shaped bodies. Therefore, fibers can align both parallel to the plane of the wave fronts of a first sound field and to the plane of the wave fronts of a second sound field. The fibers then lie parallel to the line of intersection of these two sound fields and thereby create a new main direction of fiber. If the main fiber direction in the machine direction is desired, the line of intersection of the sound fields must point in the machine direction, which is done by swiveling the sound field around its axis perpendicular to the fiber web.

Influencing a fibrous web by means of at least one directional sound field also has another advantage: If the sound field has penetrated the fibrous web and possibly another second sieve, white water is pressed through the outer surface of the second sieve. A skimmer following in the machine direction can then skim off this surface water. This lifting of liquids is also called levitation in physics. Is there a sound field perpendicular to the fibrous web, the effect of levitation is strongest.

A directed sound field can also be used to separate fibers that are already hooked together, because the wavy fronts penetrating the fibrous web entrain fibers, but at the latest lay them down again on the inner surface of the second sieve. This effect allows the immobility point in the dewatering section of a former to be shifted further towards the press section.

Another advantage is that when several individual fibrous webs are laid one on top of the other to form a multilayer fibrous web, these can be “woven” together by means of a directional sound field.

Another advantage of the invention is given by the decoupling of the influence on the fiber orientation and the basis weight in the headbox. In other words: by means of the invention the fiber orientation can be accomplished solely by directional sound fields, while the headbox is only responsible for the desired basis weight cross section. It goes without saying, however, that even when using a sectional headbox which is regulated in terms of consistency, the fiber orientation in the subsequent former can be improved by means of the present invention. But not only fibers can be influenced in their alignment by means of a directional sound field: Color particles generally have no spherical shape. The kaolin used in paper production even has a lamellar structure. Based on what has been said so far, it is clear that color particles can also be aligned. If these color particles - or, for example, fine metal flakes - are added to the fiber suspension, they experience a parallel alignment of these particles to the surface of the fiber web through wave fronts of a sound field lying parallel to the fiber web surface. If the - at least one - sound field does not work across the entire width of the fibrous web in this embodiment of the invention, a color signature can be introduced here, which shines through the paper, for example. If the sound field is also operated in an oscillating and intermittent manner, a line and / or grid-shaped signature can even be designed. This has the advantage that, for example, document papers and also paper money can be provided with a signature which is in the paper, is not printed and is therefore particularly forgery-proof. But fibers can also be aligned and provided with a signature, which can then be read and checked, for example, using a special lamp. This method of reading then works on the principle of light reflection and / or light transmission. Color particles in the paint pan of a coating machine or color particles on the fibrous web in a coating machine can also be aligned parallel to the fibrous web surface by means of the invention. This has the advantage that the random ink sheets are arranged in layers and can therefore slide better against each other when applied or when doctoring; ie the shear forces in the coating color are reduced by means of the invention. This sliding does not result in the paint particles getting caught or blocked, which would otherwise lead to a higher - and above all irregular - application rate. As a positive side effect, a

Sound field in the paint tray of a coating machine also dissolve clumps of paint and / or remove dissolved gases in the coating color.

Another very important advantage of the invention is that the speed of propagation of the sound field in liquid is about 1500 m / s, while the working speed of a modern paper machine is only about 30 m / s. If, for example, a sound field of approximately 100 mm in width and a frequency of 20,000 Hz is used, the fibers experience a total of 67 vibrations when they sweep over this sound field. Compared to previous former designs - with their very limited total number of strips (drainage elements) - an invented sound field according to the invention represents a significantly higher number of impulses, the impulses / vibrations of a sound field not only influencing the drainage but also specifically influencing the fiber orientation. This just mentioned

The advantage is further enhanced if, for example, the frequency is selected to be significantly higher. Since the device according to the invention - viewed in the machine running direction - is very narrow, it can be used, for example, between two strips or instead of only a few strips (drainage elements). This means that at least a substantial number of strips are retained for the drainage process.

The sound fields according to the invention are generated by electrically operated transmitters. The transmitters consist of a drive unit and a housing. The drive is either by means of a coil, armature and membrane or piezo elements or works on the magnetostrictive or capacitive principle. The surface of the drive unit emitting the sound field exerts an essentially parallel stroke. Since the transmitters are electrically operated, the controls for the drive units can be designed in a variety of ways using electrical engineering and electronics. A central control unit allows individual vibrations to be set for each drive unit. Any periodic pulses can also be generated by superimposing vibrations. The vibrations are defined, for example, in the control unit in terms of their amplitude, phase position, frequency and energy. So that a separate cable does not have to be laid for each drive unit, it is particularly advantageous if the control takes place via a central control bus. Since different types of paper are manufactured on a paper machine and the production parameters are very diverse, it is advantageous if the parameters of the device according to the invention are stored in a database of the control unit. When a paper type is produced again, these parameters are then called up again. This saves time for finding the parameters again and thus lowers the production costs. It is also advantageous if the control unit is coupled to an online measuring system - for example a so-called measuring frame.

Further advantageous embodiments of the invention are the subject of the dependent claims and are described below with reference to the exemplary embodiments illustrated in FIGS. 9 to 43. Figures 1 to 8 show explanatory prior art.

Figure 1: embodiment of a former; Figure 2: Another embodiment of a former; Figure 3: Shaper cutout with drainage elements (strips and blades);

Figure 4: Drainage element foil;

Figure 5: Dewatering element register roller;

Figure 6: Graph of a fiber orientation cross profile;

Figure 7: Detail and top view of a fibrous web with the main fiber directions shown;

FIG. 8: enlarged section from FIG. 7;

FIG. 9: cross section through sieves and fibrous web with a sound field perpendicular thereto;

Figure 10: cross section through sieves and fibrous web with an oblique sound field;

Figure 11: Section A-A of Figure 10;

Figure 12: Section A-A of Figure 10 at a later time than in Figure 11;

FIG. 13: cross section through sieves and fibrous web with two oblique sound fields arranged one behind the other in the machine running direction;

Figure 14: Cross section through sieves and fibrous web with two oblique sound fields directly interfering with each other;

FIG. 15: cross section through sieves and fibrous web with two oblique sound fields directly interfering with one another, but arranged alternately;

Figure 16: Cross section through sieves and fibrous web with two oblique sound fields di interfering with each other and with sound field duplicator;

FIG. 17: cross section through sieves and fibrous web with an original sound field directly interfering with one another and several sound field duplicators;

Figure 18: Cross section through sieves and fibrous web with wedge-shaped sound field and diverging reflector; FIG. 19: cross section through sieves and fibrous web with a conical sound field and rotating, diverging reflector;

Figure 20: Like Figure 19, but reflected sound field perpendicular to the fibrous web;

Figure 21: Cross section through sieves and fibrous web with rotating pinhole;

Figure 22: Section of a fibrous web with different signatures; FIG. 23: cross section through sieves and fibrous web with a trapezoidal sound field;

FIG. 24: cross section through sieves and fibrous web with arrangement for standing waves;

Figure 25: Graph of a fiber orientation cross profile;

Figure 26: Section of a fibrous web;

FIG. 27: cross section through sieves and fibrous web with wedge-shaped water gap between inclined transmitter and first sieve; FIG. 28: cross section through sieves and fibrous web with a wedge-shaped water gap between the vertical transmitter and the first sieve; FIG. 29: cross section through sieves and fibrous web with a parallel water gap between the vertical transmitter and the first sieve; FIG. 30: top view of fibrous web with device for drawing a signature; FIG. 31: section AA from FIG. 30; Figure 32: Section through "Fresnel"reflector; Figure 33: top view of Figure 32; FIG. 34: section through triple prism reflector; FIG. 35: detail from view A from FIG. 34; FIG. 36: detailed view from FIG. 35; Figure 37: Cross section through sieves and fibrous web, transmitter and two reflectors; Figure 38: Cross section through sieves and fibrous web, transmitter and three reflectors; FIG. 39: section AA from FIGS. 37 and 38; Figure 40: Alternative section AA from the figures

37 and 38; Figure 41: coating unit of a coating machine; FIG. 42: section A from FIG. 41; FIG. 43: section B from FIG. 41;

1 shows a former variant from the already cited document EP 0489 094 AI. The suspension jet coming from the headbox 3 is enclosed by the two screens 1 and 2 and is initially in a first drainage section I by means of a curved drainage tion element (here formation shoe) dewatered. The subsequent drainage section II is characterized by partially fixed and partially flexible strips 5. The final drainage section III has at least one stationary drainage element (eg forming shoe, suction box or flat suction device). The forming shoe 4 also consists of lasts, which, in contrast to the lasts 5, are an integral part of the forming shoe 4.

The former of FIG. 2 is an embodiment from the document EP 0627 523 AI. The first dewatering element after the headbox 3 is a forming roller 10, which is followed by a forming shoe 4. In a further unit, double strips 9 and simple strips 5 are attached. The drainage in this twin-wire zone ends with a suction box 8 and a suction roller 7.

FIG. 3 illustrates the arrangement of spring plates 11 and strips 5 in a twin-wire zone of a former (FIG. 6 from EP 0516 601 AI). The strips 5 have ceramic coverings at their ends facing the screen 1, which are covered by a

Dovetail fit are fixed. Similar to the strips 5, the spring plates 11 cause pressure impulses on the screens 1 and 2 or on the fibrous web 12 lying in between when they move in the machine direction 15. The foil shown in FIG. 4 strips off the white water with the aid of an extended nose, which exerts a pressure pulse on the fibrous web 12. In the further path of the screen 2, this screen section arrives in the opening wedge between the foil 13 and the screen 2. The screen water adhering to the outer surface of the screen then causes a suction effect on the fibrous web 12 by the further movement of the screen.

In the example in FIG. 5, the relatively old dewatering principle of the dewatering impulse generation by register rollers 14 is shown. A screen 2 was generally only arranged on the underside of the fibrous web. When viewed in the machine direction 15, the tapered gusset between register roller 14 and screen 2 produces a pressure pulse. On the other side of the register roller 14 is an opening gusset which has a suction effect on the fibrous web 12.

The exemplary embodiments in FIGS. 1 to 5 relating to the prior art have in common that the number of impulses for the drainage and the fiber orientation or formation is very limited and that the contact pressure for the width sections (sectional adjustability) can be individually adjusted Paper machine is insufficient. Figures 6 to 8 must be viewed in context. FIG. 6 shows a graph with a measured 17 and a desired 18 fiber orientation cross profile. The letter A here stands for example for the driver side of a paper machine and the letter B accordingly stands for the drive side. The angle of the main fiber direction to the machine direction 15 is plotted on the left, vertical axis. FIG. 7 shows the section of the fibrous web 12 belonging to the graph of FIG. 6. The solid main fiber directions 20 correspond to the graph 17; the main fiber directions 20 shown in dashed lines correspond to the graph 18. The lengths of the main fiber directions 20 are intended to reflect the amount of the respective tearing length, which in this example was chosen to be the same length or the same size for each main fiber direction 20. FIG. 8 quasi shows the microscopically enlarged detail from FIG. 7. The fibers 21 are not all aligned in one direction - the main fiber direction 20 - but it can be seen that the majority of the fibers are nevertheless in the direction of the main fiber direction 20 lie. If several fibers were now aligned in the main fiber direction 20, the tearing length would increase in this direction - at the expense of the tearing length located transversely thereto. A ratio of tearing length from tearing length along (= R _L ) through tearing length across (= R _Q ) would, therefore a further shift of fibers 21 in the main fiber direction 20, increase.

FIG. 9 shows a basic idea of the invention. For a better illustration of the invention, the screens 1 and 2 and the fibrous web 12 are shown in a greatly enlarged manner in FIG. 9 (and partly also below) compared to the other components. The fibrous web 12 enclosed between the sieves 1 and 2 is penetrated by a sound field 25 which is perpendicular to the sieve plane. The sound field 25 is generated by a transmitter 22, which consists of a drive unit 23 and a housing 24. In this exemplary embodiment, between the housing 24, the

The outer surface of the sieve 2 and the surface of the drive unit 23 facing the sieve 2, including the transmission medium 27. In this exemplary embodiment, flat wavefronts 26 of the sound field 25 emanate from the surface of the drive unit 23. According to the principle of the Pohlman cell already explained, the fibers 21 align themselves parallel to the surface of the drive unit 23. Before the fibers get into the sound field 25 (shown on the left in the figure), they are random. In the sound field 25, the fibers 21 are aligned parallel to the planes of the wave fronts 26. The fibers 21 drawn in a dot shape in the sound field 25 - and also to the right thereof - represent fibers which are "rod-shaped" but are perpendicular to the image plane. The vertical arrangement of the blade The 25 causes a sound pressure that drives white water out of the fibrous web and transports it to the surface of the screen 1. This surface water 31 can then be skimmed off by a skimmer 6. Despite the permeability of a sieve to a sound field 25, it nevertheless represents a resistance. The more permeable the sieve is made in this exemplary embodiment, the more surface water 31 is generated.

The liquid transmission medium 27 is very similar in composition and composition to the white water; because there is the possibility of mixing with one another, it makes sense if the transmission medium 27 itself consists of white water or clear water. The transmission medium 27 is important for the invention because it provides good acousto-mechanical coupling between the drive unit 23 and the fibrous web 12. Would be, for example - at least

Part - if there is an air cushion between the drive unit 23 and the fibrous web 12, the energy of the drive unit 23 would only be transferred to the fibrous web 12 to a small extent. An air cushion in the sieve mesh is not to be expected in the dewatering section of a former because the mesh of the sieve is filled with white water here.

In contrast to FIG. 9, in FIG. 10 the transmitter 22 is at an angle 30 against the planes of FIG Fibrous web 12 inclined. The fibers 21 are not aligned parallel to the screens 1 and 2 here, but are parallel to the cutting plane AA. FIG. 11 shows the section plane AA and the alignment of all fibers in this plane. If the cutting plane AA has moved further in the machine direction 15 and the screens 1 and 2 have moved closer to one another, then finally all the fibers 21 have an orientation transverse to the machine direction 15. Since this orientation is usually not desired, a different orientation of the fibers 21 - based on the machine direction 15 - can be set by changing the pivoting angle 29 of the transmitter 22. The inclination of the transmitter 22 against the fibrous web 12 reduces the effect of expelling white water, but an arrangement of a skimmer 6 would also be conceivable in FIG.

The arrangement of an inclined transmitter 22 in FIG. 10 enables the fibers 21 to be aligned, which has an effect on the fiber orientation transverse profile.

Another basic idea of the invention is shown in FIG. Viewed in the machine direction 15, the fibrous web 12 is successively influenced by two sound fields 25. If the fibers 21 initially align themselves with the left sound field 25, those fibers become when the fibers 21 pass through the right sound field 25 21 aligned, which are transverse to the right sound field 25. After passing through the fibrous web 12 through the right sound field 25 at the latest, all fibers are aligned transversely to the machine direction 15. The alignment of the fibers 21 with two intersecting sound fields 25 is particularly effective when the sound fields 25 are at right angles to one another. Since a fiber alignment in the machine direction 15 is usually desired, the action of two sound fields 25 in succession in the machine direction 15 is not yet the structurally most favorable solution. If the machine running direction were perpendicular to the image plane in FIG. 13, the sound fields 25 would not intersect.

In Figure 14, two sound fields 25 are arranged such that they intersect in the fibrous web 12. The machine direction 16 drawn in (perpendicular to the image plane; arrow in or out of the image plane) makes it clear that the fibers are now parallel to the machine direction 16. Again, the fibers 21 are particularly effectively aligned when the sound fields 25 are at right angles to one another.

However, the sound fields 25 crossing each other in the fibrous web 12 do not have to act from one side of the fibrous web 12. FIG. 15 shows a solution in which the blade the 25 from each side of the fibrous web 12, act on it. However, this arrangement is not yet structurally satisfactory, because if the desired fiber orientation is changed, if possible both sound fields 25 must be pivoted synchronously by a pivot angle 29. This requires an adjustment mechanism on each side of the fibrous web 12.

A better solution is shown in FIG. 16. Here, too, two intersecting sound fields 25 act on the fibrous web 12. The first sound field 25 is generated directly by a transmitter 22. A so-called duplicator 32 is arranged in this sound field 25. This duplicator 32 consists of a preferably flat wall. The shape of the second sound field 25 arises according to the reflection laws for sound on the surface of the duplicator wall. The inclination of the duplicator 32 with respect to the first sound field 25 is selected such that both sound fields intersect in the fibrous web 12 (the angle of the duplicator wall to the center line of the first sound field is half as large as the angle between the sound field center lines) , The advantage of this construction is that only one transmitter 22 is still required, but two sound fields 25 are still available and in the case of a pivoting of the transmitter 22 to a different pivoting angle 29, only one pivoting mechanism is required. In FIG. 17 there are also intersecting sound fields 25 that were generated by means of duplicators 32. The difference from FIG. 16 is that only one transmitter 22 (in this case standing vertically on the fibrous web 12) and several duplicators generate the sound fields 25. The vertical sound field 25 also promotes the effect of levitation. Because of the large number of duplicators 32 used here, the distance from the surface of the drive unit 23 to the surface of the screen 2 facing it can be made very short for reasons of geometry. The width and the deflection angle of the duplicated sound fields 25 can be influenced or the “free passages” for the undeflected sound field 25 can be determined by suitable selection of the parameters a, b, c for the duplicators 32. The dashed, vertically drawn lines represent further transmitters 22 - which are viewed in the machine running direction 16 - are arranged, for example, behind the image plane. The other lines drawn in dashed lines represent sound fields 25 and duplicators 32 of these further transmitters 22. In addition, the transmitter 22 could also be pivotable about a sieve normal. In another

Embodiment, the transmitter 22 - alone or together with its duplicators 32 - can also be inclined to the plane of the fibrous web 12.

However, the wave fronts 26 do not always have to be flat within the scope of the invention. In Figure 18 are the wave fronts 26 bowl-shaped. This is achieved by a trough-shaped surface of the drive unit 23. As a result, the wave fronts 26 approach a focal point. Here is a reflector 34 with - preferably - parallel compensation. If the reflector 34 is designed to be approximately parabolic in two dimensions and the focal point of the bowl-shaped wave fronts 26 coincides with the focal point of the reflector 34, then plane wave fronts 26 are directed onto the fibrous web in the manner shown. With the specified machine running direction 15 there is then a fiber orientation transverse to this. If, in addition, a reflector 33 - for example as a flat structure - is used, the sound field coming from the reflector 34 would be reflected back to the fibrous web 12 and would result in a further alignment of the fibers 21 according to FIG. 13. The channel-shaped drive unit 23 has the advantage that the energy of a possibly weak, bowl-shaped sound field is bundled. Because the bowl-shaped wave fronts 26 - at least near the focal point - cannot bring about an unambiguous orientation of the fibers 21, such a sound field is less suitable for aligning fibers 21 without a reflector 34. However, these bowl-shaped wave fronts 26 are suitable for, for example, white water to expel from the fibrous web 12 or to heat the fibrous web 12, for example to support its dewatering and / or drying process. In FIG. 19, the surface of the drive unit 23 has a hollow spherical shape, as a result of which the sound field 25 becomes spherical shell-shaped. The reflector 34 is advantageously designed to be three diagonally parabolic, so that the reflected sound field has essentially flat wave fronts 26. The reflector 34 is connected to an annular motor rotor 38 by means of holders 37. The ring-shaped motor rotor 38 is guided by guides 39 in the housing 24 of the transmitter 22. An annular motor stand 35 is attached to the outside of the housing 24. This motor is advantageously a stepper motor. The stepper motor can then be controlled via the connecting cable 36 by means of the step frequency, the control of the running direction and the number of steps in the corresponding running direction. Different speeds, forward and backward running, swiveling movements (possibly only by a fraction of an angular degree) or certain angular positions are possible. The sound field 25 striking the fibrous web 12 is thus no longer stationary and can then "write" together with the movement of the fibrous web 12 in the machine direction 15 or 16. Fibers, color particles or leaflets - for example made of metal - experience a defined orientation through the sound field in the fibrous web 12, which can then be seen as the signature 40 in the finished paper as the sieves 1 and 2 come closer in the further dewatering process. A magnetic signature can also be generated for magnetizable metal particles.

The signature can also be made with ponds that are volume-elastic. This has the advantage that a raised signature, for example, which has been smoothed by the surface pressure of the drying cylinders or the smoothing rollers, can then be erected again.

In the context of the invention, a continuous metal strip, such as in the case of banknotes, can also be held in position. According to the invention, this metal strip can also be prevented from twisting about its longitudinal axis.

An optional reflector 33 can throw the sound field back into the fibrous web. Depending on the dimensioning of the sound field located in the fibrous web 12, this produces either a parallel signature 40 or, in the case of intersecting sound fields, the signature becomes more pronounced. If the sound field 25 coming from the drive unit 23 is operated intermittently, one can control the movements and the speed of the motor rotor 38 and the operation of the drive unit via a control logic depending on the machine direction 15 or 16, the associated speed Write signature 40 (as a defined pattern or lettering) on the paper. In contrast to FIG. 19, the sound field 25 in FIG. 20 is perpendicular to the fibrous web 12. This is possible because the sound field coming from the drive unit 23 can be guided into the reflector 34 by means of a deflection 41. The vertical sound field now brings about an alignment of the fibers and any color particles or metal flakes that are present parallel to the fibrous web surface, without the subsequent approximation of sieves 1 and 2 being necessary. Through an optional use of a reflector 33 and a coordinated sound wavelength, even the sound field in the fibrous web can be designed as a standing wave. A standing wave basically has the constructive design option that the heavier matter accumulates in the wave bellies. The lighter matter then concentrates away from the wave bellies. This results in a deliberate stratification which, together with the "writing" by means of a sound field 25, creates a three-dimensional signature possibility, which is retained even after the paper has dried and can thus even be felt. Human tactile ability is already given with unevenness of one hundredth of a millimeter. If, for example, the white water is the lighter material in the described layer formation, it is fed to the sieves and can leave them more easily. This method can also be used to ensure that the smallest - clogging the mesh of the sieves - tear away there and move towards the wave belly. In this way, sieve cleaning is even possible. It goes without saying that the use of standing waves can also be used without a "writing" sound field. This will be dealt with in later figures.

Another variant of FIGS. 19 and 20 is shown in FIG. 21. Here, the sound field 25 coming from the drive unit 23 - in this example - applies directly to the fibrous web 12. Around a narrow sound field for "writing" obtained, a pinhole 42 - for example with only one eccentric hole - is arranged in the motor rotor 38. FIG. 21 is intended to show this exemplary embodiment only as an example. The relatively long way shown here from the surface of the drive unit 23 to the fibrous web 12 can be shortened in construction.

FIG. 22 shows various signatures 40. The signature in example a) was generated by means of a circular sound field 25 and the movement of the fibrous web 12. In example b) the sound field 25 carried out different swiveling movements which were overlaid with the movement of the fibrous web 12. Finally, in example c), the sound field 25 circled, which in turn was overlaid with the translational movement, but the sound field was in intermittent operation, so that a "writing with discontinuation with a fictitious Pen "was also possible. Of course, other figures are also possible within the scope of the present invention, for example Lissajous figures, cycloids, epicycloids, lemniscates, etc.

In the description of FIG. 18, it was discussed that bowl-shaped wave fronts 26 - at least near the focal point - are not well suited for an alignment of the fibers 21. A sound field 25 with shell-shaped wave fronts 26 is shown in FIG. The wavefronts 26 penetrating the fibrous web 12 correspond approximately from the middle section of a sound field 25 between the surface of the drive unit 23 and the focal point of the sound field 25. In this section the wavefronts 26 are sufficiently flat so that in addition to levitation in a fibrous web 12, too a limited fiber orientation is possible. If the wave fronts 26 penetrating the fibrous web 12 originate from a section of the sound field 25 which is even closer to the surface of the drive unit 23, they are to be used to an even better extent for the fiber orientation. If the transmitter 22 is inclined against the plane of the fibrous web 12 or the sieves 1 and 2, the fiber orientation cross profile of a fibrous web 12 can even be influenced.

With FIG. 24, the embodiment of the invention in a - here inclined - dewatering section of a former will be discussed in more detail. In this exemplary embodiment, two opposing transmitters 22 are arranged in the left region of the fibrous web 12. The transmission media 27 present between the drive units 23 of these transmitters 22 are provided with feed lines 43 and discharge lines 44. The housings 24 of the transmitters 22 are provided with sliding surfaces 45 (preferably made of ceramic) to the interface of the screens 1 and 2. The sliding lining 45 is provided with an opening in its interior so that the transmission medium 27 and thus also the wave fronts 26 are in a vibration-mechanical connection with the fibrous web 12. Through the movement of the sieves 1 and 2 in the machine direction 15, the transmission medium 27 may be entrained. In order to compensate for this loss of transmission medium 27, the supply lines 43 are present. Since in the current exemplary embodiment the transmitters 22 are operated in such a way that a standing shaft 49 forms between them and therefore white water can escape from the side of the sieves 1 and 2 facing away from the fibrous web 12, the rooms with the transmission medium 27 must also be provided with a discharge line 44 so that there is no accumulation of white water or transmission medium 27 or water. Because within the scope of the invention, when working with sound fields 25, especially in the high-frequency range, air bubbles can form in the transmission medium 27, it is important that the discharge line 44 is at the highest point of the transmission medium 27 so that the air bubbles are removed. can be led. If a supply line 43 and a discharge line 44 are present at the same time, a continuous exchange of the transmission medium 27 is possible. This is advantageous because the transmission medium 27 also serves to cool the drive unit 23, the sliding linings 45 and the screens 1 and 2. In addition, a transmission medium 27 which may become contaminated gradually becomes renewable again and again. If feed lines 43 and discharge lines 44 are used at the same time, care should be taken to ensure that there is no overpressure in the transmission medium 27 relative to the fibrous web 12, because otherwise the transmission medium 27 is pressed into the fibrous web 12. In the upper arrangement in FIG. 24, the transmitter 22 is assigned a reflector 33 with a sensor 47. This sensor 47 is equipped with a sensor measuring line 48. This measuring line 48 allows the frequency of this transmitter 22 to be set by means of a control loop in such a way that the desired waveform - here standing wave 49 - is generated. The sliding linings 45 of the reflector 33 and the transmitter 22 are - facing the screens 1 and 2 - provided with a radius or a wedge-shaped bevel, so that small amounts of surface water 31 produce a water film. As a result, there is no dry friction between the sliding linings 45 and the screens 1 and 2.

Figures 25 and 26 must be considered together. The figures 6 and 7 already show that Connections of the influencing of the fiber orientation cross profile are presented. FIG. 25 shows a desired fiber orientation cross profile 18. FIG. 26 illustrates a section of a fibrous web 12 with the sound fields 25 arranged underneath. The elliptical shape of the sound fields 25 results because round sound fields fall onto the fibrous web 12 at an incline. The dashed line, which is congruent with the smaller diameter of the ellipse, shows the intersection of the wavefronts 26 with the fibrous web 12 and thus at the same time the main direction of fiber set 20. If, for reasons of space, the sound fields 25 - and thus the transmitters 22 - are not transverse to the machine - NEN running seal 15, arranged side by side, so it is also possible without disadvantage for a fiber orientation cross profile to be set, the arrangement of the sound fields 25 or the transmitter 22 in two rows. This two-row arrangement is even recommended in connection with an overlap 51 of the sound fields 25 because almost all fibers 21 of the fibrous web 12 are exposed to approximately the same length of time or the same amount of energy when they sweep over the sound fields 25. If an edge strip 50 is cut off on each long side of the fibrous web 12 between the former and the press section of a paper machine, the use of sound fields up to the outermost edge of a fibrous web 12 is not necessary. In FIGS. 27, 28 and 29 the machine running direction should be perpendicular to the image plane. These figures are transmitters which are operated, for example, magnetostrictively. The transmission medium 27 is only present as a liquid film in these exemplary embodiments. In Figures 27 and 28 there is a wedge-shaped gap between the transmitter surface and the screen 2. In addition, the transmitter surface is inclined to the direction of vibration 52. When the wave fronts 26 leave the transmitter surface, they are deflected by the transition from the denser to the thinner medium (= liquid transmission medium 27) in the manner shown. This represents a refraction of a sound field 25. One by the movement of the

Sieves 1, 2 and the loss of transmission medium 27 due to the fibrous web 12 is compensated for by surface water 31.

FIGS. 30 and 31 show a write head 53 for writing or drawing signatures 40. This write head 53 is an alternative device to the devices from FIGS. 19 to 21. This device has the advantage that - apart from the drive units 23 - no moving parts are required. FIG. 30 shows the top view of the write head 53 - without screen 1. The device is characterized in that several transmitters 22 - possibly also in planes one above the other - are arranged in a star shape around the area of a fibrous web 12 to be described. are arranged. This star-shaped arrangement allows sound fields 25 to be arranged compactly around the area of a fibrous web 12 to be described. The sound fields 25 are guided into the area to be described by means of channels 55. By sweeping over the fibrous web 12 of this writing head 53, cell-shaped areas are created, for which at least one transmitter 22 does the writing work. A suitable control - similar to the control for a needle or inkjet printer - can be used to generate a figure or a character or some other type of signature from individual sound field activities. The diameters of the channels 55 may be only a few millimeters. The result of this is that the fibrous web 12 stays only a fraction of a second over these channels 55 when it sweeps over the channels 55, but these areas of the fibrous web 12 can be sufficiently exposed to wave fronts 26 by a corresponding frequency of the sound fields 25, preferably in the ultrasound range.

The path of the sound fields 25 from the transmitters 22 to the fibrous web 12 from FIG

Figure 30 are more clearly highlighted. The channels 55 are deflected by means of the reflectors 33. The surface of the write head 53 is either spaced apart from the screen 2 (this gap being wetted with surface water 31) or the latter

Surface is provided with a sliding coating 45. Around to recover the energy of the sound fields 25 possibly emerging through the sieve 1, a flat reflector 33 can be arranged here. With a suitable adjustment of the wavelength, standing waves 49 can even be generated between the reflector 33 and the surface of the drive unit 23 - and thus also in the fibrous web 12.

FIG. 32 shows a reflector 33 which is intended to reflect back a sound field 25 which is inclined towards the screen surfaces or the fibrous web 12. For this it is necessary that the reflecting surfaces of the reflector 33 are parallel to the wave fronts 26. Due to the saw-shaped cross section shown, the reflector 33 can be built very flat. To a certain extent, the principle of the flat Fresnel lens was applied here. The indicated, dash-dotted shape of the reflector 33 has a simple structure but builds more in height and is therefore possibly not suitable in terms of design.

The top view of FIG. 32 is shown in FIG. 33. The incompletely shown transmitter 22 is here below the sieves and the fibrous web 12. An ellipse can be seen in the center of FIG. 33. This is the intersection of the sound field 25 with the plane of the sieves or the fibrous web 12. The vertical, dashed lines show the edges of the ribs of the saw-shaped reflector 33. So that the space between the sieve 1 and the reflecting surface is filled, rinsed and / or can be cooled, the reflector 33 has a feed line 43 and a discharge line 44 for the transmission medium. If a different swivel angle 29 of the sound field 25 is required for a correction of the fiber orientation cross profile and the reflection of the sound field 25 is to be retained, a synchronous change in the swivel angle of the reflector 54 is also necessary.

A further embodiment of the reflector 33 is shown with FIGS. 34 to 36. Here, the reflective surface consists of several composite triple mirrors. These triple mirrors are known from optics and reflect a light beam on the three mutually perpendicular mirror surfaces after three reflections back to its origin. This reflection also applies to the wave fronts 26 of a sound field 25. This triple mirror reflector has the decisive advantage over the saw-shaped reflector that when the sound field 25 is pivoted, a simultaneous pivoting of the reflector is not necessary. This saves the adjustment facial expressions and is also easier and quicker to use. If a transmission medium supply line 43 is attached in the manner shown and channels 55 direct the transmission medium 27 into the outermost corner of each triple mirror, it cannot close in the corners the particularly easy occurrence of fiber residues or dirt.

FIG. 35 shows view A from FIG. 34. The lamellar structure of the triple mirror arrangement is also visible here. This lamellar structure is of great advantage because the corners of a "hollow" triple mirror cannot be machined with a cutting or grinding tool. By means of fixing options 56 - for example clamping screws - large triple mirror plates can be assembled from many slats. FIG. 36 shows slats in a single view, the first (top) slat having the same pattern of surfaces as the last. If you imagine the third lamella rotated by 180 degrees in the paper plane, you can see that this is also identical to the first and last lamella.

FIGS. 37 and 38 show an approximately realistic representation of the proportions of the sieves 1, 2 or the fibrous web 12 to the other components. So far, the screens and the fibrous web have been shown enlarged in the figures - for reasons of illustration.

In FIG. 37, two sound fields 25 - which are generated by only one transmitter - are crossed with one another. The angle shown is preferably a right angle. After the sound field 25 the Has left the surface of the transmitter 22, it is reflected after penetrating the sieves 1, 2 and the fibrous web 12 on the horizontal reflector 13 towards the inclined reflector 33. Two intersecting sound fields 25 are already present in the fibrous web 12. As a result, the fibers 21 align in the machine direction 16. In order to be able to continue using the reflected sound field energetically, the inclined reflector is oriented in such a way that it reflects the reflected sound field back into itself. The sound field thus arrives again at the horizontal reflector 33 and from there to the surface of the transmitter 22. By a suitable selection of the wavelength and the distance dimensions, even a standing wave can be generated

Wave belly lies in the plane of the fibrous web.

The space between the screen 2 and the cross member 57, which preferably extends over the entire width of the machine, is filled with the transmission medium 27. The transmitter 22 and the inclined reflector 33 are advantageously on a mounting disc

58 arranged. As a result, the swivel angle 29 of the transmitter and the swivel angle 54 of the reflector 33, which is inclined here, coincide and thus only one adjustment mimic is required. In this example, the traverse 57 serves as an assembly level on or on which the other components are arranged. The mounting disc 58 is rotatably mounted on the cross member 57 by means of a retaining ring 60. A seal

59 prevents leakage of the transmission diums 27 in the lower part of the housing 61, which should remain dry because of the electrical lines 46. A servomotor for the swivel angles 29, 54 can be attached between the round rim of the mounting disk 58 - which is provided with teeth, for example - and - for example - the retaining ring 60.

The device shown in FIG. 38 is intended to show an improved variant of the device from FIG. 37. In FIG. 37, the diameter of the retaining ring 60 is approximately three times as large as the width of the crossed sound fields in the fibrous web 12. As a result, at least three rows of mounting disks 58 lying one behind the other - viewed in the machine direction 16 - should be arranged , which must then be offset from one another transversely to the machine running direction 16, so that the entire width of a fibrous web 12 can be covered with crossed sound fields. The use of a further reflector 33 - here drawn vertically - enables the transmitter 22 to be positioned differently, so that the diameter of the holding ring 60 can be significantly reduced. In the case of a desired covering 51 (see FIG. 26), a two-row arrangement of the crossed sound fields is sufficient in the device of FIG. A two-row arrangement can thus be installed between strips 5 of a former. Although the distance shown in FIG. dotted line = middle wave beam) from the inclined to the horizontal reflector is different than the distance from the horizontal reflector to the surface of the transmitter 22, a wave antinode can still be positioned in the plane of the fibrous web by generating several wave bellies (= standing waves) for the entire distance be and one of these wave bellies is placed in the plane of the fibrous web 12.

The section A-A indicated in FIGS. 37 and 38 can be carried out in the variants of FIGS. 39 and 40. The course of the sound fields 25 in FIGS. 37 and 38 was shown with the reflector of FIG. 39. In order to better emphasize the course of the incident sound field 25 to the reflected sound field 25, a slight swivel angle 29 of the transmitter or a slight swivel angle 54 of the reflector was assumed.

The recess in the reflector 33 in FIG. 40 causes the reflection plane to shift. In order for the reflection of a sound field to take place with as little energy loss as possible, this recess must be filled with transmission medium 27. Because sound fields 25 can drive white water out of the sieves 1, 2 or the fibrous web 12, the reflector 33 with a recess and a discharge line 44 is advantageous because the white water can then flow away. They also put the sieve 1 touching surfaces, two strips 5 or a double strip 9 with the known advantages. Depending on the hydrodynamic conditions, the transmission medium 27 may also be supplemented via the feed line 43. Since a large number of these feed 43 and exhaust lines 44 are present, these openings 43 and 44 can also be used for flushing the recess and for cooling the reflector 33.

It should also be mentioned at this point that screens with narrow meshes - depending on the energy of the sound field - can be so dense that they can also perform the function of a flat reflector.

FIGS. 41 to 43 are intended to show a further area of application for directional sound fields. It has already been explained that not only fibers, but also additives in paper production can be aligned by directional sound fields. Figures 41 to 43 are for use in a coating machine, but the solution described can also be used in the so-called gluing of a fibrous web.

In FIG. 41, the counter roller 62 of a coating machine rotates in the direction indicated. The fibrous web 12, which partially wraps around the counter roller 62, is also moved. In a color range ne 64, an application roller 63 is partially immersed in the coating color. The fibrous web 12 runs through in the nip between the application roller 63 and the counter roller 62 and takes over the coating color from the application roller 63. As the counter-roller 62 continues to rotate, excess coating ink is stripped off the fibrous web 12 by means of a doctor blade 67. The doctor blade 67 can be designed both as a blade and as a roller doctor blade.

If, as shown in FIG. 41, a transmitter 22 is arranged between the doctor blade 67 and the application roller 63, the ink particles are aligned parallel to the wave fronts (the

The coating color is the transmission medium 27 for the wave fronts). Because of the large diameter of the counter-roller 62, the particles are then also virtually parallel to the surface thereof and to the surface of the fibrous web 12. Color particles which have a platelet-like basic shape - such as kaolin - are then arranged in layers in this parallel orientation. If the squeegee then wants to strip off the excess ink, the parallel ink sheets slide better against each other. This significantly reduces the shear forces in the coating color. Under certain circumstances, this means that ink can be applied just the height of one color sheet. This saves coating color and technical effort for drying and energy for the Drying. The ink particles can also be aligned in the ink tank 64 below the surface of the ink bath 65 and in the vicinity of the application roller 63 by means of a transmitter 22, so that the transmitter 22 between the application roller 63 and doctor blade 67 can be omitted if necessary. The transmitter 22 in the ink tray 64 also has the advantage that clumps of paint can be dissolved and / or the coating color can be degassed.

The counter-roller 62 and the application roller 63 are in a way a reflector for the transmitters 22 shown here. If the surfaces of the transmitters 22 are also concave and also have the same center of curvature as the rollers assigned to them, one can also generate standing waves here despite the curved surfaces.

FIG. 42 shows the enlargement of view A and FIG. 43 shows the enlargement of view B from FIG. 41. These figures do not require any further explanation because they are - above all in connection with the list of reference symbols - self-explanatory.

LIST OF REFERENCE NUMBERS

1 sieve

2 sieve 3 headbox

4 Curved formation shoe

5 bars

6 skimmers

7 suction roller 8 suction box

9 double strips

10 forming roller

11 spring plate

12 fibrous web / suspension layer 13 foil

14 register roller

15 machine direction in the image plane

16 machine direction perpendicular to the image plane

17 measured fiber orientation cross profile 18 desired fiber orientation cross profile

19 angles of the main fiber direction

20 main fiber direction

21 fiber

22 transmitter 23 drive unit

24 housing

25 sound field 26 wavefront

27 Transmission medium 28 Direction of propagation of the sound field

29 Swivel angle of the transmitter Inclination of the transmitter to normal surface water Duplicator Reflector Reflector with parallel compensation Ring-shaped motor stand Connection cable holder Ring-shaped motor runner Guide for motor runner Signature Redirection Perforated screen Feed line for transmission medium Discharge line for transmission medium Sliding surface Electrical connection Sensor Sensor measuring line Standing wave Edge strips Covering Direction of vibration Print head Swivel angle of the reflector Channel Fixing option Traverse Mounting disc Seal Retaining ring Housing counter roller applicator roller ink pan surface of the ink bath ink application squeegee

Claims

Patent claims

1. Process for processing a fibrous web or a suspension layer (12) in a paper, cardboard or coating machine or

Glue press for influencing a web property profile, characterized in that for influencing the web property profile, at least one sectional, directed

Sound field (25) is used, i.e. that the sound field is narrower than the width of the fibrous web or suspension layer (12) and that the sound field (25) is directed at components of the fibrous web or at a defined angle

Suspension layer (12) acts.

2. The method according to claim 1, characterized in that the web property profile is perpendicular to the

Level of the fibrous web or suspension layer (12) standing profile - the so-called Z-profile.

3. The method according to at least one of claims 1 or 2, characterized in that the web property profile is a transverse profile, ie this profile lies transversely to the machine running direction (15, 16) and in the plane of the fibrous web or suspension layer (12).

4. The method according to at least one of claims 1 to 3, characterized in that the sound field generated by a transmitter (22).

(25) is transmitted by means of a liquid transmission medium (27).

5. The method according to at least one of claims 1 to 4, characterized in that at least one further sectional, directed sound field (25) acts on a section of the components of a fibrous web or suspension layer (12), this further

Sound field (25) - viewed in the machine direction (15, 16) - can be offset from the first sound field (25).

6. The method according to claim 5, characterized in that the first sound field (25) and the second sound field (25) simultaneously act on the components of a fibrous web or suspension layer (12) and thereby - at least partially - interfere with one another.

7. The method according to at least one of claims 1 to 6, characterized in that the second sound field (25) is generated by reflection - of at least a part - of the first sound field (25).

8. The method according to at least one of claims 1 to 7, characterized in that a standing wave (49) acts on the components of the fibrous web or the suspension layer (12).

9. The method according to claim 8, characterized in that the standing wave consists of at least one sound field (25) and - at least a part - of its reflection.

10. The method according to at least one of claims 1 to 9, characterized in that the direction of the sound field (25) is deflected by means of refraction at its transition from solid to liquid matter.

11. The method according to at least one of claims 1 to 10, characterized in that by means of at least one sound field (25).

Layering of the components of the fibrous web or a suspension layer (12) in Z-

Direction is influenced.

12. The method according to at least one of claims 1 to 11, characterized in that by means of at least one sound field (25).

Alignment of components of the fibrous web or a suspension layer (12) to the spatial axes is influenced.

13. The method according to at least one of claims 1 to 12, characterized in that the fiber orientation - i.e. the fibers in the plane of a fibrous web or a suspension layer (12) - is influenced by means of at least one sound field (25).

14. The method according to at least one of claims 1 to 13, characterized in that the dry content of a fibrous web or a suspension layer (12) is influenced by means of at least one sound field (25).

15. The method according to at least one of claims 1 to 14, characterized in that by means of at least one sound field (25).

Tear length ratio of a fibrous web or a suspension layer (12) is influenced.

16. The method according to at least one of claims 1 to 15, characterized in that the flocculation of a fibrous web or a suspension layer (12) is influenced by means of at least one sound field (25).

17. The method according to at least one of claims 1 to 16, characterized in that the layer height of a paint application on a fibrous web or a suspension layer (12) is influenced by means of at least one sound field (25).

18. The method according to at least one of claims 1 to 17, characterized in that the layer height of a glue application on a fibrous web or a suspension layer (12) is influenced by means of at least one sound field (25).

19. The method according to at least one of claims 1 to 18, characterized in that at least two fibrous webs or suspension layers (12) lying one on top of the other are woven together by means of at least one sound field (25).

20. The method according to at least one of claims 1 to 19, characterized in that at least one sound field (25) is operated intermittently.

21. The method according to at least one of claims 1 to 20, characterized in that the oscillations of the at least one sound field (25) are formed by superposition ^ro of at least two superimposed oscillations of different frequencies.

22. The method according to at least one of claims 1 to 21, characterized in that the frequency of the sound field (25) is more than

is 20,000 hertz.

23. Paper or cardboard according to at least one of the method claims 1 to 22, characterized in that at least one web property profile by means of at least one sectional, directed

Sound field (25) is influenced.

24. Paper or cardboard according to claim 23, characterized in that the fibrous web or the suspension layer

(12) through at least one sound field (25) witness contains - at least one - signature (40).

25. Paper or cardboard according to at least one of claims 23 or 24, characterized in that the fibrous web or the suspension layer

(12) contains magnetizable particles.

26. Paper or cardboard according to at least one of the

Claims 23 to 25, characterized in that the fibrous web or the suspension layer

(12) contains volume elastic particles.

27. Paper or cardboard according to at least one of claims 23 to 26, characterized in that a metal strip located in the fibrous web or in the suspension layer (12) is fixed in its position by means of at least one sound field (25).

28. Device for processing a fiber web or a suspension layer (12) in a paper, cardboard or coating machine or size press to influence a web property profile, characterized in that - at least one sectional transmitter (22).

Sound field (25) generated, - and a liquid transmission medium (27) is arranged between the transmitter (22) and the components of the fibrous web or the suspension layer (12).

29. The device according to claim 25, characterized in that the transmitter (22) is arranged in a sieve section (former).

30. The device according to claim 25, characterized in that the transmitter (22) is arranged in a press section, the surface of the transmitter (22) being directed directly onto a press felt or onto the fibrous web - for expelling or for heating water.

31. The device according to claim 25, characterized in that the transmitter (22) is arranged in a drying section, the surface of the transmitter (22) being directed directly onto the fibrous web (12) - for heating the water in the fibrous material.

32. Device according to claim 25, characterized in that the transmitter (22) is arranged in a coating machine.

33. The device according to claim 25, characterized in that the transmitter (22) is arranged in a size press.

3. Device according to at least one of claims 25 to 30, characterized in that the transmitter (22) has a supply line (43) for transmission medium (27).

35. Device according to at least one of claims 25 to 31, characterized in that the transmitter (22) has a withdrawal line (44) for the transmission medium (27), the withdrawal line (44) preferably being at the highest point of the transmission medium (27). Transmitter (22) is attached.

36. Device according to at least one of claims 25 to 32, characterized in that at least one reflector (33) is assigned to the transmitter (22).

37. Device according to claim 33, characterized in that the reflector (33) is essentially flat.

38. The device according to claim 33, characterized in that the reflector (33) is concavely curved - preferably parabolic.

39. Device according to claim 33, characterized in that the reflector (33) is sawtooth-shaped.

40. The device according to claim 33, characterized in that the reflector (33) is designed in the form of - at least - a hollow triple mirror.

41. The device according to claim 37, characterized in that the at least one hollow triple mirror is constructed from individual slats.

42. Device according to at least one of claims 25 to 38, characterized in that the housing (24) of the transmitter (22), at the end facing the fibrous web (12) or the sieve (2), has a sliding coating (45) is provided.

43. Device according to at least one of claims 25 to 39, characterized in that the sound field (25) is moved by means of a motor - preferably a stepper motor.

44. Device according to at least one of claims 25 to 39, characterized in that the plurality of sound fields (25) are applied to the fibrous web or by means of channels (55) of a - preferably star-shaped - writing head (53).

Suspension layer can be applied.

45. Device according to at least one of claims 25 to 39, characterized in that the - at least one - transmitter (22) is mounted on a traverse (57) - which preferably extends across the machine.

46. The device according to claim 42, characterized in that the - at least one - transmitter (22) is mounted on a rotatable mounting disk (58) and can be adjusted to a pivot angle 29 and this mounting disk (58) is attached to the traverse (57).