NOZZLE

Abstract

An oscillating nozzle, in particular for a cleaning device, includes a fluid oscillator having an oscillation chamber. The oscillating nozzle is configured in an angled manner, so that the plane of the fluid jet is deflected in the interior of the nozzle. The deflection occurs downstream of the oscillation chamber. A cleaning device and a suction roller are also provided.

Claims

1-15. (canceled)

16. An oscillating nozzle for ejecting a fluid jet or an oscillating nozzle for ejecting a fluid jet in a cleaning device, the oscillating nozzle comprising: a fluid oscillator having an oscillation chamber; and a nozzle interior being angled for deflecting the fluid jet along a jet plane in said nozzle interior downstream of said oscillation chamber.

17. The oscillating nozzle according to claim 16, which further comprises two ducts guiding a fluid stream downstream of said oscillation chamber, an island separating said two ducts, and an overrun region, said jet plane being deflected in said overrun region.

18. The oscillating nozzle according to claim 16, wherein said jet plane is deflected by an angle of between 1° and 90°.

19. The oscillating nozzle according to claim 16, wherein said jet plane is deflected by an angle of between 5° and 45°.

20. The oscillating nozzle according to claim 16, which further comprises an exit of the oscillating nozzle, and at least one lip disposed at said exit for preventing the fluid jet from widening perpendicularly to said jet plane.

21. The oscillating nozzle according to claim 16, wherein said fluid jet oscillates and sweeps an oscillation angle in a range of between 90° and 170°.

22. The oscillating nozzle according to claim 16, wherein said fluid jet oscillates and sweeps an oscillation angle in a range of 120°.

23. The oscillating nozzle according to claim 16, wherein the nozzle is completely or partially composed of a metal or a plastics material.

24. The oscillating nozzle according to claim 16, wherein the nozzle is constructed to be integral or in one piece.

25. A cleaning device able to clean a suction roller for a plant for producing or processing a fibrous web, the cleaning device comprising: a distribution line; and a plurality of cleaning nozzles configured to be supplied with a cleaning fluid by said distribution line and to eject a fluid jet; at least one or each of said plurality of cleaning nozzles being an oscillating nozzle according to claim 16.

26. The cleaning device according to claim 23, wherein said plurality of cleaning nozzles includes a first quantity and a second quantity of oscillating nozzles each having a jet plane exit angle, and said jet plane exit angles of said first quantity of cleaning nozzles and of said second quantity of cleaning nozzles are different.

27. The cleaning device according to claim 26, wherein one oscillating nozzle of said first quantity of cleaning nozzles and one oscillating nozzle of said second quantity of cleaning nozzles are disposed in an alternating manner.

28. The cleaning device according to claim 26, wherein said jet plane exit angle of said first quantity of cleaning nozzles and said jet plane exit angle of said second quantity of cleaning nozzles differ by more than 2°.

29. The cleaning device according to claim 26, wherein said jet plane exit angle of said first quantity of cleaning nozzles and said jet plane exit angle of said second quantity of cleaning nozzles differ by between 5° and 25°.

30. The cleaning device according to claim 25, which further comprises a releasable connection, a screw connection or a plug connection connecting said plurality of cleaning nozzles to said distribution line.

31. The cleaning device according to claim 25, wherein said plurality of cleaning nozzles are disposed at a mutual spacing of less than 500 mm.

32. The cleaning device according to claim 25, wherein said plurality of cleaning nozzles are disposed at a mutual spacing of between 150 mm and 350 mm.

33. A suction roller for a plant for producing or processing a fibrous web, the suction roller comprising at least one cleaning device according to claim 25.

34. The suction roller according to claim 33, wherein the cleaning device is disposed in an interior of the suction roller.

Description

[0063] Further advantageous developments of the invention will be explained by means of exemplary embodiments with reference to the drawings. The features mentioned can be advantageously implemented not only in the combination illustrated but can also be combined individually with one another. In the figures:

[0064] FIGS. 1a, 1b and 1c show examples of the fluid oscillators from the prior art.

[0065] FIG. 2 schematically shows a section through the construction of an angular oscillating nozzle according to one aspect of the invention.

[0066] FIG. 3 schematically shows views of an angular oscillating nozzle according to one aspect of the invention.

[0067] FIG. 4 schematically shows a fragment of a cleaning device according to another aspect of the invention.

[0068] FIGS. 5a, 5b and 5c show details pertaining to a cleaning device according to one aspect of the invention.

[0069] The figures will be described in more detail hereinbelow.

[0070] FIGS. 1a, 1b and 1c schematically show different design embodiments of fluid oscillators as are known from t prior art. These fluid oscillators are suitable for use in oscillating nozzles 20 according to different aspects of the present invention. However, the present inventions are not limited to these embodiments of the fluid oscillators. In general, all types of fluid oscillators are suitable.

[0071] The fluid can enter the flow chamber through an inlet 1. An acceleration nozzle, for example in the form of a constriction, can optionally be provided, as is shown in FIG. 1c. The fluid thereafter enters the oscillation chamber 3. Depending on the type of the oscillator, flow obstacles 6 in the form of islands 6 can be provided in the oscillation chamber 3. Alternatively or additionally, return flow ducts 4 which return parts of the flow of fluid back in the direction of the inlet 1 can also be provided. At the outlet 7 the fluid exits the oscillator as an oscillating jet 10.

[0072] In the embodiment in FIG. 1a, the flow runs straight through the oscillator, that is to say that the direction of the inflow into the inlet 1 lies in the plane of the oscillating jet 10. In the embodiments as per FIGS. 1b and 1c the flow inlet 1 is illustrated from below. A deflection of the flow takes place ahead of the actual oscillator.

[0073] FIG. 2 shows an angular oscillating nozzle 20 according to one aspect of the invention. In this embodiment, the fluid is directed into the nozzle 20 by way of an inlet 1. While not mandatory, the fluid is then advantageously directed through an acceleration nozzle 2 into the oscillator chamber 3 by way of the oscillator inlet 3a. An oscillator which comprises two return flow ducts 4 is illustrated in FIG. 2. The nozzle in FIG. 2 has a constriction 5 at the location where the outlet 7 is disposed in the known oscillators. Thereafter, the fluid is directed through two ducts 12 which are separated by an island 6. It is very advantageous for the ducts and the island 6 to have a high degree of symmetry. The island 6 can in particular be embodied so as to be circular, elliptic, teardrop-shaped or similar.

[0074] The ducts 12 are converged again behind the island 6, and the fluid as an oscillating jet subsequently exits the nozzle 20 by way of an outlet 7. The region between the constriction 5 and the outlet 7 is referred to as the overrun region 11. The overrun region 11, conjointly with the oscillator, here forms the interior of the nozzle 20. In order to achieve that the oscillating jet 10 and the inflow direction do not lie in the same plane, the oscillating nozzle 20 is embodied so as to be angular. In order for the effect of the oscillator not to be disturbed, the nozzle 20 is angled by an exit angle within the overrun region. This exit angle can advantageously be between 1° and 90°, in particular between 5° and 45°. An angle of 30° is illustrated in an exemplary manner in FIG. 2.

[0075] In order to avoid that the oscillating jet 10 is widened after the outlet 7, a lip 8 is provided in the nozzle 20 in FIG. 2. This lip 8 prevents the downward evasion by the jet 20. Alternatively or additionally it can be provided that a lip 8 which prevents the upward evasion by the jet is provided. The lip 8, or lips 8, respectively, are not angled or curved, respectively, in FIG. 2 but embodied so as to be straight. Angling or curving the lips 8 is also not necessary for deflecting the jet because the angling takes place already prior thereto in the interior of the nozzle 20.

[0076] Nevertheless, in some cases it may be expedient for an additional curvature, or an additional angulation, respectively, to be provided in the region of the lips 8.

[0077] Such an angular oscillating nozzle 20 can be used for a multiplicity of applications. Said angular oscillating nozzle 20 is extremely suitable for the use as an oscillating nozzle 20 in a cleaning device 100 according to one aspect of the invention.

[0078] An angular oscillating nozzle 20 according to one aspect of the invention is again illustrated in various views from the outside in FIG. 3. The profile of the internal flow chambers is plotted as a dashed line. B1 here refers to the inlet width after the acceleration nozzle 2; B2 refers to the width of the constriction 5; B3 refers to the width of the ducts 12; and B4 refers to the width of the outlet 7. These four widths B1-B4 in conjunction with the length of the lip 8 influence the development of the oscillating jet 10. A jet propagation of 120° in the jet plane, this having been demonstrated as very advantageous, can be achieved, for example, when the widths B1 and B2, thus the inlet width and the width of the construction, are identical. The width of the ducts as well as of the outlet opening may be somewhat wider than the inlet width B1.

[0079] Particularly advantageous here is the combination:

B2=B1

B3=1.25*B1

B4=1.5*B1

[0080] The absolute values for these widths of course 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 chosen for example between 1 mm and 5 mm, in particular as 2 mm.

[0081] The geometry of the flow chambers advantageously is consistent across the entire height of said flow chambers. In the embodiment in FIG. 2 the height H is chosen so as to be equal to the inlet width B1. This results in a square cross section of the inlet 1.

[0082] The length of the lip 8 can advantageously be at least three times the inlet width B1. This is advantageous with a view to achieving a jet 20 bundled in the direction of the normal.

[0083] A very advantageous embodiment of the oscillating nozzle thus has the following dimensions:

TABLE-US-00001 B1 B2 B3 B4 H Lip 2 mm 2 mm 2.5 mm 3 mm 2 mm ≥6 mm

[0084] The nozzles 20 shown in FIGS. 2 and 3 at the base have in each case a thread. This is advantageous with a view to connecting to a fluid supply line. Alternatively, this connection can also be performed for example by way of a plug connection. A simple replacement of the nozzles 20 is possible in both cases. Depending on the applications, however, other types of connections, in particular also non-releasable connections, to the fluid line may be provided.

[0085] FIG. 4 shows a fragment of a cleaning device 100 according to one aspect of the invention. Such a cleaning device 100 can in particular be used as a cleaning device 100 for a suction roller 130 for a plant for producing or processing a fibrous web. A multiplicity of cleaning nozzles 120a, 120b are attached to a distribution line 110 which can be embodied as a distributor pipe 110. These cleaning nozzles 120a, 120b can be supplied with a cleaning fluid such as, for example, splash water, by the distribution line 110. The cleaning fluid can be supplied by way of a single fluid connector 111 or by way of a plurality of fluid connectors 111 of the distribution line 110. All cleaning nozzles in FIG. 4 are embodied as oscillating nozzles 20. It is particularly advantageous for the cleaning nozzles to be designed as angular oscillating nozzles 20, for example such as are described in FIGS. 2 and 3. The embodiment in FIG. 4 has a first quantity 120a and a second quantity 120b of angular cleaning nozzles, wherein the exit angle of the jet plane of the first quantity 120a and that of the second quantity 120b are dissimilar. A difference of 5°-10° in the angles is often advantageous. It can thus be provided, for example, that the exit angle of the first quantity 120a is 30° and the exit angle of the second quantity 120b is 35°.

[0086] It is advantageous for the spacing between two adjacent cleaning nozzles to be between 150 mm and 350 mm. A cleaning device 100 in which the mutual spacing of the cleaning nozzles is variable is illustrated in FIG. 4. The cleaning nozzles here are positioned for example in groups of two composed of a nozzle of the first quantity and a nozzle of the second quantity, for example. This can be advantageous as will be explained below by means of FIG. 5c.

[0087] Alternatively, the spacing of adjacent cleaning nozzles may also be identical, for example 250 mm. However, it can be also provided, for example, that in regions where contamination is less likely, for example on the periphery of a suction roller 130, larger spacings between the cleaning nozzles are provided than in the other regions.

[0088] A potential method for positioning the cleaning nozzles in a cleaning device according to one aspect of the invention is to be explained by means of FIGS. 5a, 5b and 5c. The installed situation of a cleaning device 100 in a suction roller 130 is illustrated in FIG. 5a. The distribution line 110 here runs parallel, or at least largely parallel, to the axis of the suction roller 130. The cleaning device 100 comprises, for example, a first quantity 120a and a second quantity 120b of angular oscillating nozzles 20 which are disposed in an alternating manner. The respective exit angles are provided with the reference signs θ1 and θ2. The spacing of the cleaning device 100 from the casing of the suction roller 130 (measured from the exit point of the jet from the nozzle) is I.sub.d. FIG. 5b shows a device as in FIG. 5a in a plan view. To be seen here is the oscillation angle θW, thus the angle which is swept by the oscillating jet 10 when oscillating. This oscillation angle can be between 90° and 170°, for example. As can be seen in FIG. 5b, the nozzles 20 can be disposed such that the regions in which the jets 10 oscillate overlap in the case of adjacent nozzles. In this instance it is advantageous for respective adjacent nozzles 20, 120a, 120b to have different exit angles θ1, θ2. As a result, the jet planes of adjacent nozzles lie in space such that the jets to not contact one another and thus do not interfere with one another. As can be seen in FIG. 5a, the jet of the first quantity θ1 impacts the casing of the suction roller 130 above the jet of the second quantity θ2.

[0089] FIG. 5c illustrates why overlapping of adjacent jet regions according to one aspect of the invention is not only possible without problems but indeed advantageous. The graph shows the volumetric flow of fluid of four adjacent oscillating nozzles 20. A typical “M profile” can be seen here, meaning that less fluid per unit of time impacts the suction roller 130 in the center of the swept region than toward the peripheries. This is generally typical of oscillators. As described, the distribution of the fluid can be homogenized by using an overrun region 11, as a result of which wider oscillation angles θW, or larger swept regions bs become possible, respectively. As a result, the cleaning device 100 can be implemented with fewer nozzles 20. It can be seen that the nozzles of the first quantity 120a are positioned such that the jets of said nozzles do not contact one another. The nozzles of the second quantity 120b now can be positioned such that the regions with a high volumetric flow of the fluid are where there is a smaller impact of the volumetric flow of the nozzles of the first quantity 120a, and vice versa. It can thus be achieved that the casing of the suction roller 130, or else other moving areas to be cleaned or to be humidified, respectively, are on average impinged uniformly with fluid across the width.

[0090] The variable bs in FIG. 5c moreover describes the width of the region swept by the oscillating jet 10. With the aid of the oscillation angle θW and the spacing of the oscillating nozzle 20 from the casing of the suction roller 120, this width is derived from

[00002]$b_S=2l_d\tan \frac{\theta W}{2}$

[0091] It has proven advantageous for the cleaning nozzles, as is illustrated in FIG. 4, to be positioned in groups of two composed of a nozzle of the first and of the second quantity. These two nozzles of one group have the spacing I.sub.A, while the spacing from the first nozzles of the next group of two is I.sub.B. Here, it preferably applies that I.sub.A=0.25 bs, and I.sub.B=0.75 bs. This results in particularly homogenous cleaning of the suction roller 130. In more general terms, the spacings should be chosen as:

l.sub.A∈[0.2, 0.3]b.sub.S; l.sub.B∈[0.7, 0.8]b.sub.S

LIST OF REFERENCE SIGNS

[0092] 1: Inlet

[0093] 2: Acceleration nozzle

[0094] 3: Oscillation chamber

[0095] 3a: Oscillator inlet

[0096] 4: Return flow ducts

[0097] 5: Constriction

[0098] 6: Island

[0099] 7: Outlet opening

[0100] 8: Lip

[0101] 9: Exit angle

[0102] 10: Oscillating jet

[0103] 11: Overrun region

[0104] 12: Duct

[0105] 15: Flow chamber

[0106] 20: Oscillating nozzle

[0107] 100: Cleaning device

[0108] 110: Distribution line

[0109] 111: Fluid connector

[0110] 120a: First quantity

[0111] 120b: Second quantity

[0112] 130: Suction roller

[0113] B1: Inlet width

[0114] B2: Width of the constriction

[0115] B3: Width of the ducts

[0116] B4: Width of the outlet opening

[0117] H: Height of the flow chamber

[0118] θ1, θ2 Exit angles

[0119] θW Oscillation angle