NOZZLE

Description

[0001] The invention relates to an oscillating nozzle, in particular for a cleaning device according to the preamble of claim 1, as well as a cleaning device with an oscillating nozzle and a suction roller with a cleaning device.

[0002] In the production of paper, board, and tissue products—as well as in the production of nonwoven products—suction rolls or blow rolls are used in many areas. These rolls have a perforated roll shell. During operation, suction rolls create a vacuum, so that air / water or other fluid streams are drawn through the perforations of the roll shell. Similarly, blow rolls create a positive pressure, so that a fluid stream is blown through the roll shell.

[0003] The fluid streams passing through the perforations of the suction roll typically carry a varying amount of contaminants. These can be mineral components, such as limescale in the process water, or mineral filler particles from the paper, or even fibers or fines from the paper or nonwoven product. This contaminant gradually accumulates at the edges of the perforations, completely or partially blocking them.

[0004] Even partially blocked perforations in the roll shell lead to disruptions in the production process. The effects depend heavily on the function of the suction or blowing roll. For example, in a suction roll used to guide or stabilize the fibrous web, blocked perforations can lead to web flutter. In suction press rolls, the dewatering performance decreases. In particular, uneven contamination of the perforations in the cross direction of the roll can also impair web quality parameters such as the moisture cross-section.

[0005] One possible solution is to clean the suction roll at regular intervals. However, this involves downtime of the production plant and the time-consuming removal and installation of the roll, which incurs high costs for the operator.

[0006] In the prior art, in particular DE 10 2008 002 259, it was therefore proposed to equip the suction roll with a cleaning device. A cleaning head is installed inside the roll, which has a number of nozzles from which a cleaning fluid is sprayed through the perforations at a certain pressure to remove the contaminants.

[0007] In conventional suction rolls in the paper or nonwoven industry, the individual perforations have a very small diameter of just a few millimeters. Several hundred such holes are arranged across the width of a suction roll, which can be 10m or more, and these holes can also be offset from one another in so-called drilling patterns. It is therefore technically and economically almost impossible to use a separate cleaning nozzle for each hole. DE 10 2008 002 259 solves this problem by designing a movable cleaning head within the roll. By oscillating the cleaning head, a single nozzle can clean a certain width of the roll shell. The disadvantage of this solution, however, is that the mechanism required to move the cleaning head is very complex and expensive. Furthermore, the required mechanical and hydraulic components are always prone to failure and require regular maintenance.

[0008] In addition, this cleaning system requires a comparatively large installation space. As a result, such a cleaning system cannot be used in suction rolls with a small diameter. DE 10 2017 206849 A1 discloses further fluidic components for creating an oscillation of the fluid flow at the outlet opening according to the prior art.

[0009] It is therefore an object of the present invention to propose an improved nozzle which is also suitable for use in a cleaning system in a suction roll.

[0010] It is a further object of the present invention to propose a cleaning system and a suction roll that overcome the problems of the prior art.

[0011] The objects are fully achieved by an oscillating nozzle according to the characterizing part of claim 1, as well as a cleaning system according to the characterizing part of claim 8 and a suction roll according to the characterizing part of claim 14. Advantageous embodiments are specified in the dependent claims.

[0012] For ease of reading, aspects of the invention are explained and claimed using the example of a suction roll. Unless explicitly stated otherwise, this always includes blow rolls.

[0013] With regard to the cleaning system, the object is achieved by a cleaning device, in particular for a suction roll, for a system for producing or processing a fibrous web, wherein the cleaning device comprises a distribution line and a number of cleaning nozzles that can be supplied with a cleaning fluid via the distribution line. It is provided that at least one, in particular all, of the cleaning nozzles are designed as oscillating nozzles.

[0014] Advantageous embodiments are described in the dependent claims.

[0015] It is clear to the person skilled in the art that the cleaning nozzles in such a cleaning device must be arranged in such a way that the emerging fluid jet hits the roller shell or the perforations.

[0016] Devices known for a long time under the term "fluid oscillator" or "fluid oscillator" are devices that can be used to generate a fluid jet that oscillates in a plane, creating a fan-shaped pattern. Such oscillators are described, for example, in European Patent Specification EP 0 007 950 and the literature cited therein. In contrast to a classic fan nozzle, the jet itself is not fan-shaped, but can essentially be point-shaped. By appropriately designing the nozzle geometry, the jet can be made to oscillate back and forth. As the explanations in EP 0 007 950 - which will be discussed in more detail later - show, no moving parts are necessary for this, which means the oscillator is very wear-resistant and requires little maintenance.

[0017] Such fluid oscillators have so far been used primarily in areas such as the automotive industry. The company Bowles Fluidics ( www.bowlesfluidics.com) markets such oscillators, for example, as wiping nozzles for headlights and windshields. The inventors have recognized that such an oscillator is surprisingly also suitable for use in cleaning suction rolls. It has been shown that such an oscillator has three properties that make it suitable for use in a cleaning device for a certain area of ​​the roll shell - particularly in the CD direction - and can therefore clean several adjacent perforations. In contrast to the cleaning devices known from the prior art, this occurs without the need for a mechanism or a hydraulic device to move the nozzle. Furthermore, it has been shown that the energy of the jet or the fluid when it hits the roll shell is high enough to achieve a sufficient cleaning effect. Finally, such oscillators can be manufactured very compactly.This allows the size of the cleaning device to be kept significantly smaller than in the prior art. This makes it possible to satisfy a long-standing need among manufacturers and to produce such cleaning devices even for suction rolls with very small diameters or with a particularly small distance between the suction box and the casing.

[0018] Advantageously, the oscillating nozzles are aligned so that the jet oscillates in the same direction for all oscillating nozzles, or these directions differ by less than 10°. When such a cleaning device is installed in a suction roll or in or on another unit of a fiber machine, this oscillation can advantageously occur in the CD direction.

[0019] The cleaning devices according to various aspects of the present invention are, as described, particularly suitable for cleaning suction and blow rolls. However, they can also be used advantageously for cleaning or moistening other parts of a paper or nonwoven machine. One example here is the cleaning or conditioning of clothing, in particular screens or felts.

[0020] In In preferred embodiments, it can be provided that the jet emerging from the oscillating nozzles covers an angle in the range between 90° and 170°, preferably between 110° and 130°, particularly preferably 120°, during oscillation.

[0021] InIn an advantageous embodiment, the cleaning device can be provided with a first set and a second set of oscillating nozzles, wherein the exit angle of the jet plane of the first set and the second set differs from one another. In particular, it can be provided that one oscillating nozzle each of the first and second sets is arranged alternately.

[0022] The advantage of differently directed jets is that they impact the roll shell at different circumferential positions. This makes it possible to position adjacent cleaning nozzles as close to each other as desired, without the risk of the emerging fluid jets crossing and potentially reducing the cleaning effect, since the jet from the adjacent nozzle always impacts the roll shell slightly above or below. It has proven advantageous for this purpose if the exit angle of the jet plane of the first and second jets differs by more than 2°, particularly between 5° and 25°.

[0023] If necessary, third, fourth, etc. exit angles can also be provided depending on the application.

[0024] Unless otherwise specified, the exit angle should be determined as the angle that the beam plane makes with the vertical.

[0025] In the oscillators known from the prior art, the flow path is straight, meaning that the direction in which the fluid flows into the oscillator lies in the plane of the oscillating jet. Using such oscillators, different exit angles of the jet plane can be achieved simply by changing the inflow direction accordingly.

[0026] The distribution line can advantageously be a cylindrical, or essentially cylindrical, pipe. By installing the above-mentioned straight oscillators at different angles into the distribution line, different outlet angles can be achieved.

[0027] However, such a design can result in an increase in the size of the cleaning device. Furthermore, from a manufacturing perspective, it would be desirable if all cleaning nozzles could be installed in the distribution line in a row and at the same angle.

[0028] It would therefore be highly desirable if the deflection of the jet plane could occur within the nozzle itself. However, this cannot be achieved by simply bending the known oscillator geometries, as this would otherwise prevent the formation of an oscillating jet.

[0029] To solve this problem, the inventors improved the known fluid oscillators in such a way that the jet plane is deflected within the nozzle, while still maintaining the oscillating jet. These angled oscillating nozzles represent a further invention in themselves and are described in more detail later in this application.

[0030] As mentioned above, it can be advantageous for the cleaning device if at least some, in particular all, of the oscillating nozzles are angled so that the jet plane is deflected inside the nozzle.

[0031] For example, due to impurities in the cleaning fluid, the cleaning nozzles, especially the oscillating cleaning nozzles, can become clogged after a certain period of time. Furthermore, wear and tear during operation can also cause damage to the cleaning nozzles. In contrast to the complicated maintenance of the cleaning device described in the prior art, the cleaning nozzles in the cleaning device according to one aspect of the invention can be easily replaced.

[0032] Changing the cleaning nozzles can be particularly easy if the cleaning nozzles are connected to the distribution line via a detachable connection, in particular a screw or plug connection.

[0033] In an advantageous embodiment, the cleaning nozzles are mounted next to one another on the distribution line, with the distance between two adjacent cleaning nozzles advantageously being less than 500 mm, for example between 150 mm and 350 mm. It can be advantageous if not all nozzles are evenly spaced. In particular, to achieve a uniform cleaning effect, it can be advantageous if the nozzles are arranged in groups of two, and the distance IA of the nozzles in a group of two is smaller than the distance IB to the next group of two. Details of this will be explained in more detail with reference to the figures. Alternatively, it can also be expedient if the cleaning nozzles are provided evenly along the distribution line.

[0034] With regard to the suction roll, the object is achieved by a suction roll for a plant for producing or processing a fibrous web, wherein the suction roll comprises at least one cleaning device according to one aspect of the invention.

[0035] While the cleaning device can in principle also be installed outside the suction roll, it is usually advantageous if the cleaning device is arranged inside the suction roll.

[0036] If the cleaning device is located inside a suction roll, the width of the area covered by the oscillating jet of a nozzle depends on the oscillation angle θW and the distance of the oscillating nozzle from the suction roll casing. This width is determined using the formula: b s = 2 l d tan θW 2

[0037] It is advantageous if an oscillating nozzle of a set (e.g. the first set or the second set) is spaced from the next nozzle of this set by this distance bs or further in order to avoid any influence of the oscillating jets by the jets of the neighboring nozzles

[0038] The invention further comprises a method for cleaning a suction roll according to one aspect of the invention.

[0039] The cleaning device can be subjected to a fluid, in particular a spray water, wherein the fluid has a pressure of less than 40 bar, in particular less than 10 bar, preferably between 1 and 5 bar.

[0040] At pressures above 40 bar, the material of the cleaning device is subjected to considerable stress, causing rapid wear. However, sufficient cleaning performance can often be achieved even at lower pressures, especially between 1 and 5 bar.

[0041] Furthermore, it can be advantageous to use less than 20 l / min / m, especially between 9 l / min / m and 11 l / min / m, for cleaning. This low water consumption is economically and ecologically desirable and simultaneously enables good cleaning effectiveness.

[0042] However, especially when working with higher fluid pressures, especially above 5 bar, it can also be helpful to clean with larger fluid quantities, for example 30 l / min / m, 40 l / min / m or even more.

[0043] The cleaning process described can be carried out either continuously during the operation of the suction roll or only in discrete cleaning intervals, which can also occur during a machine downtime.

[0044] As already mentioned above, the angled oscillating nozzles represent a further invention which can be used for a cleaning device according to one aspect of the previous invention, but are also suitable for a variety of other applications.

[0045] Starting from the known fluid oscillators, e.g. EP 0 007 950, it is the object of the further invention to provide an oscillator, in particular an oscillating nozzle, in which the direction of the fluid entering the oscillator is not in the plane of the oscillating jet.

[0046] This object is achieved by an oscillating nozzle, in particular for a cleaning device as described above, wherein the oscillating nozzle comprises a fluid oscillator and the oscillating nozzle is angled so that the jet plane is deflected inside the nozzle, characterized in that the deflection takes place after the fluid oscillator.

[0047] Advantageous embodiments are described in the dependent claims.

[0048] The fluid oscillator in the angled nozzle often includes an oscillation chamber after the oscillator inlet and usually one or two return channels. The shape and arrangement of these channels cause the oscillation of the fluid jet, which then exits the fluid oscillator at an outlet. While oscillators designed in this way are advantageous, the invention is not limited to them.

[0049] Attempts to angle the nozzle in the area of ​​the oscillator often fail because this prevents or impedes the formation of the oscillation. Therefore, the inventors consider the angle toward the oscillator outlet to be advantageous.

[0050] According to the invention, the nozzle geometry is designed such that the fluid is guided downstream of the oscillation chamber via at least two channels separated by an island. This region is referred to as the wake region. The deflection of the jet plane occurs in this wake region. The channels can advantageously be symmetrical. It can also be advantageous if the width of the channels remains constant, or at least largely constant, over their entire length. It should be particularly understood that the channel width in the initial and final regions can differ from the width in the remaining region. Such a design has proven to be very advantageous, as it allows a very wide range of angles to be realized without impairing the effect of the oscillator.

[0051] The inventors have discovered that providing a wake region and positioning the deflection within this wake region is particularly advantageous. Despite the complex internal structure of the oscillator or the entire flow chamber, nozzles of the described type can be manufactured very easily and cost-effectively using additive processes ("3D printing"). The nozzles can be made from a variety of materials, e.g., metals and / or polymer materials. A disadvantage of such additively manufactured nozzles, however, is that the inner surfaces of the flow chamber are usually relatively rough, making post-treatment inside the nozzle difficult or even impossible. This internal roughness means that when using a nozzle without a wake region, a large portion of the fluid is discharged in the area of ​​the reversal points of the oscillating jet.As a result, only limited opening angles can be achieved in practice, as otherwise insufficient fluid is delivered in the areas between the reversal points. The downstream wake, preferably in the ring shape described, can achieve a noticeable homogenization of the fluid delivery. Furthermore, it has surprisingly been shown that in this wake, the nozzle can be angled over a wide range of angles without impairing the formation of the oscillation.

[0052] In particularly advantageous embodiments, it can be provided that the beam plane is deflected by an angle between 1° and 90°, in particular between 5° and 45°.

[0053] Furthermore, it can be advantageous if at least one lip is provided at the outlet of the oscillating nozzle after the outlet opening to prevent the jet from expanding perpendicular to the jet plane. It can be particularly advantageous if two lips are provided. This can prevent the jet from expanding both upwards and downwards.

[0054] Advantageously, the length of the lip may be at least three times as long as the width of the oscillator inlet.

[0055] Even if it is clear to the person skilled in the art from the above, it should be emphasized again at this point that the term "interior of the nozzle," i.e., the area where the deflection of the jet plane takes place, refers to the area between the inlet, specifically between the oscillator inlet, and the outlet opening. This is where the flow chamber with the oscillator and the wake area is located. Any lips that may be provided are therefore not considered part of the interior of the nozzle.

[0056] The lip or lips are typically straight, not angled or curved. Bending or curving the lips isn't necessary to deflect the jet, as the bending is already done inside the nozzle.

[0057] Nevertheless, in some cases it may be useful to provide an additional curvature or angulation in the area of ​​the lips. Such designs are also encompassed by the present invention.

[0058] In preferred embodiments, it can be provided that the emerging beam covers an angle in the range between 90° and 170°, preferably between 110° and 130°, particularly preferably 120°.

[0059] Depending on the desired application or availability, the angled oscillating nozzle can be made from a variety of materials. These include metals such as steel, aluminum, etc., as well as plastics such as polyamide, especially PA12, or polyethylene.

[0060] In preferred embodiments, the nozzle may be made in one piece.

[0061] Another major advantage is that these nozzles can also be manufactured using additive processes.

[0062] Further advantageous embodiments of the invention are explained using exemplary embodiments with reference to the drawings. The features mentioned can be advantageously implemented not only in the illustrated combination, but also individually combined with one another. The figures show in detail: Figures 1a, 1b and 1c show examples of state-of-the-art fluid oscillators. Figure 2 shows schematically a section through the structure of an angled oscillating nozzle according to one aspect of the invention. Figure 3 shows schematic views of an angled oscillating nozzle according to one aspect of the invention. Figure 4 shows schematically a section of a cleaning device according to another aspect of the invention. Figures 5a, 5b and 5c show details of a cleaning device according to one aspect of the invention

[0063] The figures are described in more detail below.

[0064] The Figures 1a, 1b and 1c schematically show various designs of fluid oscillators as known from the prior art. These are suitable for use in oscillating nozzles 20 according to various aspects of the present invention. However, the present inventions are not limited to these designs of fluid oscillators. In general, all types of fluid oscillators are suitable.

[0065] The fluid can enter the flow chamber through an inlet 1. If necessary, as in Figure 1cAs shown, an acceleration nozzle may be provided, e.g., in the form of a taper. The fluid then enters the oscillation chamber 3. Depending on the type of oscillator, flow obstacles 6 in the form of islands 6 may be provided in the oscillation chamber 3. Alternatively or additionally, return flow channels 4 may also be provided, which redirect portions of the fluid flow back toward the inlet 1. At the outlet 7, the fluid then leaves the oscillator as an oscillating jet 10.

[0066] When executed in Figure 1a the flow goes straight through the oscillator, that is, the direction of the inflow into the inlet 1 lies in the plane of the oscillating jet 10. In the embodiments according to Fig. 1b and 1c The flow inlet 1 is from below. The flow is deflected before the actual oscillator.

[0067] Figure 2shows an angled oscillating nozzle 20 according to one aspect of the invention. In this embodiment, the fluid is introduced into the nozzle 20 via an inlet 1. Advantageously, although not absolutely necessary, the fluid is then guided through an acceleration nozzle 2 via the oscillator inlet 3a into the oscillator chamber 3. In Figure 2 An oscillator is shown which comprises two return channels 4. At the point where the outlet 7 is located in the known oscillators, the nozzle in Figure 2 a constriction 5. The fluid is then passed through two channels 12 separated by an island 6. It is very advantageous if the channels and the island 6 exhibit a high degree of symmetry. In particular, the island 6 can be circular, elliptical, teardrop-shaped, or similar.

[0068] Behind the island 6, the channels 12 are reunited, and the fluid subsequently leaves the nozzle 20 as an oscillating jet via the outlet 7. The area between the constriction 5 and the outlet 7 is referred to as the wake area 11. The wake area 11, together with the oscillator, forms the interior of the nozzle 20. To ensure that the oscillating jet 10 and the inlet direction are not in the same plane, the oscillating nozzle 20 is angled. To avoid disrupting the effect of the oscillator, the nozzle 20 is angled by an exit angle within the wake area. This exit angle can advantageously be between 1° and 90°, in particular between 5° and 45°. Figure 2 An angle of 30° is shown as an example.

[0069] In order to avoid widening of the oscillating jet 10 after the outlet 7, the nozzle 20 is provided with Figure 2A lip 8 is provided. This prevents the beam 20 from deflecting downward. Alternatively or additionally, a lip 8 may be provided to prevent the beam from deflecting upward.

[0070] The lip 8 or lips 8 are in Figure 2 not angled or curved, but straight. Bending or curving the lips 8 is also not necessary to deflect the jet, since the bending already occurs beforehand inside the nozzle 20. Nevertheless, in some cases it may be useful to provide an additional curvature or bending in the area of ​​the lips 8.

[0071] Such an angled oscillating nozzle 20 can be used for a variety of applications. In particular, it is ideally suited for use as an oscillating nozzle 20 in a cleaning device 100 according to one aspect of the invention.

[0072] In Figure 32 shows an angled oscillating nozzle 20 according to one aspect of the invention in various external views. The course of the internal flow spaces is shown as dashed lines. B1 denotes the inlet width after the acceleration nozzle 2, B2 the width of the constriction 5, B3 the width of the channels 12, and B4 the width of the outlet 7. These four widths B1-B4, combined with the length of the lip 8, influence the shape of the oscillating jet 10. A jet spread of 120° in the jet plane, which has proven to be very advantageous, can be achieved, for example, if the widths B1 and B2, i.e. the inlet width and the width of the constriction, are the same. The width of the channels and the outlet opening can be somewhat wider than the inlet width B1.

[0073] The combination is particularly advantageous: B 2 = B 1 B 3 = 1 , 25 * B 1 B 4 = 1 , 5 * B 1

[0074] The absolute values ​​for these widths naturally depend heavily on the application and the desired flow rates. For an application as an oscillating nozzle 20 in a cleaning device 100 according to one aspect of the invention, the width B1 can be selected, for example, between 1 mm and 5 mm, in particular 2 mm.

[0075] Advantageously, the geometry of the flow chambers remains the same over their entire height. When designed in Figure 2 The height H is chosen to be equal to the inlet width B1. This results in a square cross-section of the inlet 1. Advantageously, the length of the lip 8 can be at least three times as long as the inlet width B1. This is advantageous for achieving a beam 20 that is focused in the normal direction.

[0076] Thus, a very advantageous design of the oscillating nozzle has the following dimensions: B1 B2 B3 B4 H lip 2mm 2mm 2.5mm 3mm 2mm ≥6mm

[0077] The Figures 2and 3 The nozzles 20 shown each have a thread at the base. This is advantageous for connecting to a fluid supply line. Alternatively, this connection can also be made via a plug-in connection, for example. In both cases, the nozzles 20 can be easily replaced. Depending on the application, other connection types, in particular non-detachable connections to the fluid supply line, can also be provided.

[0078] Figure 4shows a section of a cleaning device 100 according to one aspect of the invention. Such a cleaning device 100 is particularly suitable for use as a cleaning device 100 for a suction roll 130 for a system for producing or processing a fibrous web. A plurality of cleaning nozzles 120a, 120b are attached to a distribution line 110, which can be designed as a distribution pipe 110. These nozzles can be supplied with a cleaning fluid, such as spray water, from the distribution line 110. The cleaning fluid can be supplied to the distribution line 110 via a single fluid connection 111 or via multiple fluid connections 111. The cleaning nozzles are arranged in Figure 4 all designed as oscillating nozzles 20. It is particularly advantageous if the cleaning nozzles are designed as angled oscillating nozzles 20, for example those as shown in the Figures 2 and 3 described. The execution in Figure 4comprises a first set 120a and a second set 120b of angled cleaning nozzles, wherein the exit angle of the jet plane of the first set 120a and the second set 120b differ from one another. A difference of 5° - 10° in the angles is often advantageous. For example, it can be provided that the exit angle of the first set 120a is 30°, and the exit angle of the second set 120b is 35°.

[0079] It is advantageous if the distance between two adjacent cleaning nozzles is between 150mm and 350mm. Figure 4 A cleaning device 100 is shown in which the distance between the cleaning nozzles varies. The cleaning nozzles are positioned, for example, in groups of two, consisting of a nozzle of the first and second set. This can be advantageous, as will be shown below with reference to Figure 5 c explained

[0080] Alternatively, the distance between adjacent cleaning nozzles can also be the same, for example, 250 mm. However, it can also be provided that in regions where less contamination is expected—for example, at the edge of a suction roller 130—the distances between the cleaning nozzles are larger than in the remaining regions.

[0081] Based on the Figures 5a, 5b and 5c is intended to describe a possible method for positioning the cleaning nozzles in a cleaning device according to one aspect of the invention. Figure 5aThe installation situation of a cleaning device 100 in a suction roll 130 is shown. The distribution line 110 runs parallel to the axis of the suction roll 130, or at least largely parallel. The cleaning device 100 comprises, for example, a first set 120a and a second set 120b of angled oscillating nozzles 20, which are arranged alternately. The respective exit angles are designated θ1 and θ2. The distance between the cleaning device 100 and the casing of the suction roll 130 (measured from the exit point of the jet from the nozzle) is I d . Figure 5b shows a device as in Figure 5a in the top view. This shows the oscillation angle θW, i.e. the angle covered by the oscillating beam 10 during oscillation. This oscillation angle can, for example, be between 90° and 170°. As shown in Figure 5bAs can be seen, the nozzles 20 can be arranged such that the areas in which the jets 10 oscillate overlap in adjacent nozzles. It is advantageous here if adjacent nozzles 20, 120a, 120b have different exit angles θ1, θ2. As a result, the jet planes of adjacent nozzles are positioned in space such that the jets do not touch and thus cannot interfere. We in Figure 5a As can be seen, the beam of the first quantity θ1 hits the casing of the suction roll 130 above the beam of the second quantity θ2.

[0082] Figure 5cillustrates why an overlap of adjacent jet areas according to one aspect of the invention is not only easily possible, but also advantageous. The graph shows the volume flow of fluid from four adjacent oscillating nozzles 20. A typical 'M-profile' can be seen, which means that less fluid impinges on the suction roller 130 per unit of time in the middle of the swept area than towards the edges. This is generally typical for oscillators. As described, the distribution of the fluid can be evened out by using a trailing area 11, whereby wider oscillation angles θW or larger swept areas bs become possible. The cleaning device 100 can therefore be realized with fewer nozzles 20. It can be seen that the nozzles of the first set 120a are positioned such that their jets do not touch.The nozzles of the second set 120b can now be positioned so that the regions with high fluid flow rates are where the nozzles of the first set 120a are subjected to a lower flow rate, and vice versa. This ensures that, on average, the surface of the suction roller 130—or other moving surfaces to be cleaned or moistened—is uniformly exposed to fluid across its entire width.

[0083] The size bs in Figure 5c describes the width of the area swept by the oscillating steel 10. With the help of the oscillation angle θW and the distance of the oscillating nozzle 20 to the casing of the suction roll 130, this width results from b s = 2 l d tan θW 2

[0084] It has proven advantageous to use the cleaning nozzles as in Figure 4shown, in groups of two consisting of a nozzle of the first and the second set. These two nozzles of a group have the distance IA , while the distance to the first nozzle of the next group of two concerns IB. Preferably IA = 0.25 bs and IB =0.75 bs This results in a particularly homogeneous cleaning of the suction roll 130. More generally, the distances should be l A ∈ 0.2 , 0.3 b s ; l B ∈ 0.7 , 0.8 b s be elected. List of reference symbols

[0085] 1:Inlet 2:Acceleration nozzle 3:Oscillation chamber 3a:Oscillator inlet 4:Return flow channels 5:Constriction 6:Island 7:Outlet opening 8:Lip 9:Exit angle 10:Oscillating jet 11:Wake-up area 12:Channel 15:Flow chamber 20:Oscillating nozzle 100:Cleaning device 110:Distribution line 111:Fluid connection 120a:First quantity 120b:Second quantity 130:Suction roll B1: Inlet width B2: Width of the constriction B3: Width of the channels B4: Width of the outlet opening H: Height of the flow chamber θ1, θ2 Exit angle θWOscillation angle

Claims

1. Oscillating nozzle (20), in particular for a cleaning device (100), wherein the oscillating nozzle (20) comprises a fluid oscillator having an oscillation chamber (3) and the oscillating nozzle (20) is embodied so as to be angular such that the jet plane is deflected in the interior of the nozzle (20), wherein the deflection takes place after the oscillation chamber (3), characterized in that the fluid after the oscillation chamber (3) is guided by way of two ducts (12) which are separated by an island (6) and define an overrun region (11) and the deflection of the jet plane takes place in this overrun region (11) .

2. Oscillating nozzle (20) according to one of the preceding claims, characterized in that the jet plane is deflected by an angle between 1° and 90°, in particular between 5° and 45°.

3. Oscillating nozzle (20) according to one of the preceding claims, characterized in that at least one lip (8) for preventing the jet (10) from widening perpendicularly to the jet plane is provided at the exit of the oscillating nozzle (20).

4. Oscillating nozzle (20) according to one of the preceding claims, characterized in that the oscillating jet (10) sweeps an oscillation angle in the range between 90° and 170°, particularly preferably of 120°.

5. Oscillating nozzle (20) according to one of the preceding claims, characterized in that the nozzle (20) is completely or partially composed of a metal or a plastics material.

6. Oscillating nozzle (20) according to one of the preceding claims, characterized in that the nozzle (20) is embodied so as to be integral.

7. Cleaning device (100), in particular for a suction roller (130), for a plant for producing or processing a fibrous web, wherein the cleaning device (100) comprises a distribution line (110) as well as a number of cleaning nozzles (20) which by way of the distribution line (110) are able to be supplied with a cleaning fluid, characterized in that at least one cleaning nozzle, in particular all cleaning nozzles, is / are embodied as oscillating nozzle / nozzles (20) according to one of Claims 1 to 6.

8. Cleaning device according to Claim 7, characterized in that a first quantity (120a) and a second quantity (120b) of oscillating nozzles (20) are provided, wherein the exit angle (θ1, θ2) of the jet plane of the first quantity (120a) and that of the second quantity (120b) are dissimilar.

9. Cleaning device (100) according to either of Claims 7 or 8, characterized in that one oscillating nozzle of the first quantity (120a) and one of the second quantity (120b) are in each case disposed in an alternating manner.

10. Cleaning device (100) according to either of Claims 8 or 9, characterized in that the exit angle of the jet plane of the first quantity (120a) and that of the second quantity (120b) differ by more than 2°, in particular by between 5° and 25°.

11. Cleaning device (100) according to Claims 7 to 10, characterized in that the cleaning nozzles are connected to the distribution line by way of a releasable connection, in particular a screw connection or plug connection.

12. Cleaning device (100) according to Claims 7 to 11, characterized in that the cleaning nozzles are disposed at a spacing of less than 500 mm, in particular of between 150 mm and 350 mm.

13. Suction roller (130) for a plant for producing or processing a fibrous web, characterized in that the suction roller (130) comprises at least one cleaning device (100) according to one of Claims 8 to 12.

14. Suction roller (130) according to Claim 13, characterized in that the cleaning device (100) is disposed in the interior of the suction roller (130).