Nozzle with a first grip and a second grip surrounding the first grip and nozzle assembly

Abstract

The present invention relates to a nozzle assembly (20) for cleaning a filter element (12) by means of a fluid flow; this consists of a supply line (22) structured as a pipe with a supply line opening on one lateral surface of the supply line (22), at least one nozzle (1.1, 1.2, 1.3, 1.4) structured as a hollow body with a base surface (4.2), where the nozzle (1.1, 1.2, 1.3, 1.4) has an inlet opening (16) on its base surface (4.2) and at least one nozzle holder (23) with a housing (25) for the nozzle (1.1, 1.2, 1.3, 1.4), where the nozzle (1.1, 1.2, 1.3, 1.4) has a recess (26) on its base surface (4.2) for placement on the lateral surface of the supply line (22); Thus the inlet opening (16) is supported on the supply line (22) and aligned with the supply line opening where the nozzle (1.1, 1.2, 1.3, 1.4) The nozzle holder (23) is held detachably in its housing (25) and centered, and the nozzle holder (23) is held detachably on the supply line.

Description

Technical field

[0001] The present invention relates to a nozzle arrangement comprising a pipeline and a nozzle attached thereto. Background of the invention

[0002] Nozzles with diverse geometries and for diverse purposes are already known from the prior art, in particular as air nozzles or liquid nozzles.

[0003] When cleaning filter elements, such as cartridge filters, bag filters, flat filters, or cylindrical filters, a controlled fluid flow is used to remove a filter cake from the filter element. For example, cleaning is carried out by backflow, as known from DE 44 23 439 A1. However, cleaning can also be achieved by guiding the fluid along a surface of the filter element where the filter cake has accumulated, transversely to this surface, in order to shear the filter cake off. Cleaning a filter using an airflow is also known, for example, from DE 20 2013 100 593 U1.

[0004] In the aforementioned cleaning methods, particularly for cylindrical filter elements where the fluid flow is directed transversely to an inner surface and along the central axis of the cylindrical filter element, nozzles are used to generate or guide a specific fluid flow. For example, bursts of air are released from a compressed air tank or line via solenoid valves and directed through the nozzle onto the filter element. A disadvantage of this method is that the flow is often not sufficiently uniform across the surface to be cleaned and / or lacks sufficient momentum for complete surface cleaning. In particular, sufficient momentum or shear force cannot be achieved beyond a certain distance from the nozzle.

[0005] Another disadvantage is that known nozzles are often permanently mounted in a corresponding nozzle arrangement and are then difficult to detach from the supply line or from the nozzle arrangement, for example for maintenance or replacement.

[0006] US Patent 2004 / 0124283 A1 discloses a branching unit for a field sprayer, which is located at an inlet on a dispensing hole of a pipeline and has several pipe sections, several outlets, and nozzles arranged at the outlets for dispensing a fluid. WO 2012 / 074901 A1 discloses a similar branching unit that has integrated outlet nozzles. A similar branching unit is also disclosed, for example, in US Patent 2017 / 0050206 A1.

[0007] From DE 25 28 758 A1 a holding device for holding a nozzle on a shell surface of a pipeline in the area of ​​a transverse bore is also known, comprising a pipeline, a nozzle, an elastic intermediate piece and a metal band. Description of the invention

[0008] Starting from this situation, it is an object of the present invention to propose a nozzle arrangement that is easy to handle.

[0009] The object of the invention is achieved by the features of the independent main claims. Advantageous embodiments are specified in the dependent claims. Where technically feasible, the teachings of the dependent claims can be combined arbitrarily with the teachings of the main and dependent claims.

[0010] The advantages of the claimed aspects of the invention are explained below, followed by a description of preferred modified embodiments of these aspects. Explanations, particularly regarding advantages and definitions of features, are essentially descriptive and preferred examples, but not limiting ones. If an explanation is limiting, this will be explicitly stated.

[0011] Where elements are designated by means of a numbering system, for example, "first element," "second element," and "third element," this numbering is solely for differentiation purposes and does not imply any dependency between the elements or a mandatory sequence. This means, in particular, that a device or method does not need to have a "first element" to have a "second element." The device or method can also have a "first element" and a "third element" without necessarily having a "second element." Multiple units of an element with a single numbering system are also possible, for example, multiple "first elements."

[0012] According to one aspect of the invention, the problem is solved by a nozzle arrangement for cleaning a filter element by means of a fluid flow, comprising at least one tubular supply line with a supply line opening in a surface of the supply line, at least one nozzle designed as a hollow body with a base, wherein the nozzle has an inlet opening in the base, and at least one nozzle holder with a receptacle for the nozzle, wherein the nozzle has a recess on its base for resting against the surface of the supply line such that the inlet opening rests against the supply line and is aligned with the supply line opening, and wherein the nozzle is detachably held and centered on the receptacle of the nozzle holder, and the nozzle holder is detachably held on the supply line. The supply line is, for example, connected to a pressure tank or a pressure line.

[0013] A tubular shape is understood to be a geometry that extends primarily in one longitudinal direction. The profile can be any type of hollow profile and, for example, round or polygonal. The cross-section of the profile can be constant or variable along its length.

[0014] A nozzle is defined as a device with an inlet side or cross-section and an outlet side or cross-section, wherein a fluid flows into the nozzle at the inlet side or through the inlet cross-section and flows out of the nozzle at the outlet side or through the outlet cross-section. The fluid flow between the inlet side / cross-section and the outlet side / cross-section, and in particular by means of nozzle openings that form the outlet side or cross-section, is influenced with respect to its flow characteristics. Specifically, the fluid flow is influenced with respect to the flow contour, the flow velocity, and the mass flow. The flow contour is understood as the sum of the spatial positions and velocities traversed by the individual fluid particles. A fluid is, in particular, air, another gas, or a liquid such as water.

[0015] A filter element is designed, for example, as a cylindrical filter element, a pocket filter, a cartridge filter, or a flat filter, and comprises a filter medium such as a fleece or similar material that is permeable to part of the fluid flow to be filtered and impermeable to another part. For example, dust and particles are filtered out of an airflow in this way. The retained portions of the fluid flow to be filtered form a filter cake on and / or within the filter medium over time, depending on the amount of fluid flowing through it. This filter cake increases the flow resistance for the fluid. Cleaning involves at least partially removing the filter cake from the surface of the filter medium to reduce the flow resistance.

[0016] The solution to the problem described above comprises the teaching that a nozzle is held on the supply line by means of a nozzle holder, wherein both the nozzle and the nozzle holder are detachably held on the supply line. The nozzle holder is designed such that the nozzle is centered relative to the nozzle holder and the supply line. For example, appropriately shaped centering elements are provided on the nozzle and the nozzle holder for this purpose. This centering ensures that the nozzle's inlet opening is aligned with the supply line opening. Furthermore, this nozzle arrangement advantageously allows a nozzle to be attached to the supply line with minimal effort and tools. In this way, the nozzle arrangement can be easily disassembled and subsequently reassembled for maintenance, nozzle geometry changes, or cleaning.Furthermore, the nozzle arrangement is simple in design and inexpensive to manufacture. The nozzle arrangement described above also allows for free positioning of the nozzle on the pipeline, depending on the position of the inlet opening.

[0017] Due to the aforementioned design of the nozzle assembly, the nozzle is securely held on the nozzle holder or the supply line in all spatial directions, and in particular, it is also secured against rotation. This prevents the nozzle from slipping and / or twisting during operation of the nozzle assembly.

[0018] The inlet opening is preferably aligned transversely, and in particular exactly perpendicularly, to a central axis of the inlet or is oriented at an angle to this central axis. The recess arranged on the base of the nozzle is oriented at a corresponding angle to allow it to rest against the outer surface of the inlet.

[0019] In a preferred embodiment, the nozzle is positively locked to the nozzle holder and can be inserted into the recess from an inner side of the nozzle holder concealed by the supply line. This positive locking mechanism makes it particularly easy to attach and center the nozzle on the nozzle holder. The positive locking is preferably designed such that the nozzle assumes a centered position within it. In this embodiment, where the nozzle can be inserted into the recess from an inner side of the nozzle holder concealed by the supply line, the supply line allows for easy fixation of the nozzle in the receptacle, thus achieving centering and securing it. During assembly / disassembly of the nozzle assembly, the nozzle is then inserted into the recess or removed from the receptacle when the nozzle holder is disconnected from the supply line.

[0020] In a preferred embodiment of the aforementioned design, the nozzle has a collar and is positively locked to the nozzle holder by means of the collar. Such a collar enables the nozzle to be held securely and centrally on the nozzle holder in a simple manner, particularly when the nozzle can be inserted into the recess from an inner side of the nozzle holder concealed by the supply line, and the collar then engages the nozzle holder from behind. A collar can also serve, for example, as a sealing surface and / or for receiving a sealing compound.

[0021] In a preferred embodiment, the nozzle holder is held securely to the supply line and, in particular, clamped to the supply line in a clamp-like manner. This allows for a secure and quickly releasable hold of the nozzle holder. Furthermore, since the nozzle can be inserted into the nozzle holder from an inner side, positioning the nozzle holder on the supply line is simple and unobstructed thanks to the nozzle already inserted into the holder.

[0022] In one embodiment of the aforementioned design, the nozzle holder is designed to be hinged or bendable and secured in a folded / bent position by means of connecting elements, and clamped onto the supply line. The nozzle holder is then a single piece even in the folded / bent position and has no detachable parts. Furthermore, positioning the nozzle holder on the supply line is particularly easy when the nozzle holder is folded / bent or partially folded / bent, and securing the nozzle holder to the supply line is made particularly easy by closing the connecting elements. If the nozzle holder is designed to be hinged / bent through a sufficient opening angle, it is also possible to position the nozzle holder on the supply line in a radial direction, thus minimizing the required installation space.

[0023] In one embodiment, a plurality of nozzles are arranged on the supply line by means of a corresponding plurality of nozzle holders. The teaching of the described solution can then be used for more than one nozzle on a single supply line. In particular, several filter elements can be cleaned simultaneously, or a single filter element can be cleaned using multiple nozzles. Different nozzles with different geometries or flow contours can be used simultaneously.

[0024] Preferably, the nozzle has a projection at the inlet opening that extends into the supply opening. This ensures simple and reliable centering of the nozzle relative to the supply line and of the inlet opening relative to the supply line, and guarantees that the openings are aligned. If the inlet opening and the supply line opening are round, additional anti-rotation protection is provided, for example, by a corresponding positive fit between the nozzle and the nozzle holder.

[0025] In In one embodiment, the nozzle has at least one first nozzle section designed as a hollow truncated cone, at least one first through-pass, wherein the first through-pass forms a first nozzle opening in a cover surface of the first nozzle section, and a plurality of second through-passes surrounding the first through-pass, wherein the second through-passes form second nozzle openings in the lateral surface of the first nozzle section, wherein the second through-passes each have a through-pass axis tilted relative to a parallel axis parallel to a central axis of the nozzle in order to imprint a helical flow contour onto the fluid flow.

[0026] A hollow truncated cone is a geometry that forms a coaxial connecting surface between a round base and a round top surface that is smaller than the base. Due to its hollow shape, the truncated cone has an interior space that geometrically corresponds to the outer contour, and this interior space is free of material. The truncated cone thus forms a wall that defines the lateral surface of the outer contour and the lateral surface of the inner contour. In particular, the interior space at the base forms an inlet opening for the truncated cone, allowing a fluid flow to enter.

[0027] A through-hole is understood to be a recess through a material, in particular a wall or multiple walls, whose walls are, in particular, parallel to each other and, in particular, parallel to a through-hole axis. A through-hole can also increase or decrease in cross-section along the through-hole axis, so that the walls are then, for example, not exactly, but nearly parallel to each other. A through-hole is defined, in particular, by the direction of the through-hole axis and by its geometry. Any through-hole geometry is possible, especially with regard to the cross-section; however, a through-hole is preferably designed as a circular bore with a bore diameter.

[0028] A helical flow contour is defined by the fact that individual fluid particles follow a helical path. This imparts a swirl to the flow contour and / or the individual fluid particles.

[0029] The embodiment described above comprises the technical teaching that a first nozzle opening is provided centrally on the top surface for expelling a core flow, and several second nozzle openings are provided around the first nozzle opening on the outer surface for expelling an outer flow. The first nozzle opening, or the first opening provided for forming the first nozzle opening, is preferably arranged concentrically with the central axis of the nozzle, i.e., it has a through-axis concentric with the central axis and walls parallel to the central axis. The flow direction of the core flow thus points straight out of the nozzle. The second openings are each arranged at an angle, so that the outer flow exhibits an imprinted swirl or flow direction towards the helical shape.Advantageously, the core flow, which without the outer flow would fan out in a funnel shape relatively close to the nozzle and thus act on the surface of the filter element with significantly reduced momentum, can be constricted or focused and thus directed by the helical outer flow. By imprinting the helical flow contour, the outer flow is prevented from fanning out and acts on the entire flow contour in such a way that the flow contour is constricted / focused and stabilized in space. Such a stabilized flow contour can then act more precisely on the surface of the filter element, particularly at greater distances from the nozzle, and apply a higher momentum component to a desired area of ​​the surface.In particular, the precise geometric design of the nozzle, especially the diameter ratio of the first through-passage to the second through-passages, the number and arrangement of the second through-passages, and the selection of tilt angles by which the second through-passages are tilted relative to the parallel axes, makes it possible to precisely adapt the flow contour to specific filter elements, particularly in terms of their diameter or the development of the diameter over the axial distance from the nozzle. The flow contour then precisely fills, for example, a cylindrical filter element, and a particularly favorable shear is achieved on the inner surface of the cylindrical filter element.In simplified terms, tilting the second passages allows for a particularly stable flow contour and simple and precise control over the nozzle's directional characteristics, enabling the directional characteristics to be precisely selected for a specific application.

[0030] In one embodiment of the aforementioned design, the second through-flows are arranged on a circular path concentric with the central axis of the nozzle. The flow contour is then advantageously axially symmetrical about the central axis of the nozzle or about a core flow concentrically aligned therewith, and therefore particularly stable. Furthermore, such a flow contour is especially suitable for cleaning a cylindrical filter element. Such a cylindrical shape is a standard geometry for filter elements used in filtering airflows in industrial applications.

[0031] Furthermore, when arranging the second passages on a circular path concentric with the central axis at the nozzle, whose basic body formed at least by the first nozzle section is round in cross-section, it is advantageous to create a uniform pressure distribution within the nozzle, so that the material load on the nozzle is kept low.

[0032] In a further embodiment of the aforementioned design, the first nozzle section has a concavely tapered surface. A concave taper of the surface, or of the truncated cone, is understood to mean that the surface, in the axial direction of the truncated cone, is not linearly but rather tapers in a concave manner, decreasing sharply from the base to the top. In this sense, a truncated cone is also understood to be a geometry whose surface exhibits concavity (and / or convexity) compared to a geometrically ideal truncated cone. Advantageously, the concave taper results in an elongation of the second nozzle openings, thus increasing their cross-section and increasing the proportion of the external flow to the overall flow contour compared to a linearly tapered surface.

[0033] In a further embodiment of the aforementioned design, the nozzle has a second nozzle section, designed as a hollow cylinder, adjoining a base surface of the first nozzle section. The nozzle is then extended towards its inlet side and has an internal region in the second nozzle section within which the fluid flow can establish and stabilize itself laminarly, independent of upstream components, before the fluid reaches the nozzle openings. In this way, a stable and uniform or axially symmetrical flow is still ensured.

[0034] In particular, the second through-passes project radially outwards from the inside into an outer wall of the second nozzle section to form a contour on the inner side of the outer wall. Thus, the second through-passes overlap with the wall of the second nozzle section without, however, intersecting its outer contour. This creates groove-like recesses on the inner side of the wall of the second nozzle section. The imprinting of a swirl or a helical flow contour then advantageously occurs within the nozzle itself, namely in the second nozzle section, comparable to the imprinting of a swirl onto a bullet in a rifle by rifling in the barrel. In this way, the flow contour is further stabilized.

[0035] Furthermore, the second nozzle section has, in particular, a recess on its base for conforming to a cylindrical contour running at an angle to the nozzle's central axis, and especially a collar. The second nozzle section can then be contour-fitted to an opening in the side wall of a tubular supply line, creating a particularly flow-optimized and uninterrupted, and especially tight, transition between the supply line and the nozzle. The nozzle can be positioned with its central axis, for example, perpendicular to the supply line or at any other angle. The collar increases the contact area of ​​the nozzle on the supply line, for example, to accommodate sealing materials. However, such a collar is particularly preferably also used to hold the nozzle on the supply line, especially for positive locking.The collar is preferably formed along the recess for fitting to the cylinder contour or forms the contour itself.

[0036] In a further embodiment of the aforementioned design, the through-passage axes of the second through-passages are each tilted about a first transverse axis perpendicular to the parallel axis and intersecting the central axis of the nozzle by a first tilting angle. Preferably, the first tilting angle is 0 to 45°, particularly preferably 23°. The first tilting angle is, for example, 1°, 2°, 3°, 5°, 10°, 15°, 20°, 23°, 25°, 30°, 35°, 40°, 45°, or an angle between these values. The provision of the first tilting angle particularly influences the slope of the helical contour of the external flow. The selected first tilting angle advantageously achieves a favorable constriction of the flow contour and a favorable range of the flow contour, i.e., a sufficient distance from the nozzle at which the flow contour remains stable.

[0037] In a further embodiment of the aforementioned design, the through-passage axes of the second through-passages are each tilted about a second transverse axis perpendicular to both the parallel axis and the first transverse axis by a second tilting angle. Preferably, the second tilting angle is 0 to 90°, particularly preferably 45°. The second tilting angle is, for example, 1°, 2°, 3°, 5°, 10°, 15°, 20°, 25°, 30°, 35°, 40°, 45°, 50°, 55°, 60°, 65°, 70°, 75°, 80°, 85°, 90°, or an angle between these values. The selected second tilting angle influences the diameter or the development of the diameter over the axial distance from the nozzle of the flow contour.Advantageously, the nozzle can be adjusted in the selected range of the second tilt angle for cleaning the inner surface in the axial direction of a variety of cylindrical filter elements, especially for a variety of length-to-diameter ratios of such cylindrical filter elements.

[0038] Preferably, the reduction ratio between the inlet cross-section and the outlet cross-section of the nozzle is between 1:1 and 3:1. An inlet cross-section is formed, in particular, by an inlet opening created by the interior space at the base of the first or second nozzle section. An outlet cross-section is the sum of the cross-sections of all nozzle openings. With these ratios, a favorable ratio between the flow velocity and the mass flow of the airflow is achieved for cleaning filter elements using air pulses from a pressure tank or pressure line.

[0039] In a further embodiment of the aforementioned design, the first through-passage is round and has a diameter of 1 to 70% of the nozzle diameter. The nozzle diameter is understood here as the maximum outer diameter of the nozzle. In a further embodiment, preferably combined with this one, the second through-passages are also round and have a diameter of 1 to 70% of the nozzle diameter. With these diameters, a favorable flow contour is achieved for cleaning conventional cylindrical filter elements for air purification in industrial applications. Furthermore, a favorable ratio of core flow to outer flow is then present, resulting in a stable flow contour with a favorable reach.

[0040] An odd number of second passes is preferred. This avoids point symmetries that could have mutually canceling effects.

[0041] In In another embodiment, the nozzle has a plurality of third passages, each intersecting an inner contour of the first passage and parallel to the nozzle's central axis. These third passages contour the first passage, thereby focusing and directing the core flow. This advantageously results in a particularly well-directed and stable flow contour.

[0042] Preferably, a nozzle is manufactured using an additive manufacturing process. Advantageously, this allows for the targeted selection of one or more tilt angles for cleaning a specific filter element and enables production with minimal effort. In particular, additive manufacturing allows for complex nozzle geometries with low manufacturing costs. Brief description of the drawings

[0043] The invention is explained in more detail below with reference to the accompanying drawings and preferred embodiments. The term "figure" is abbreviated as "Fig." in the drawings.

[0044] In the drawings show Fig. 1a a perspective view of a nozzle according to a first embodiment; Fig. 1b the nozzle according to Fig. 1a in a side view; Fig. 1c the nozzle according to Fig. 1a und Fig. 1b Top view; Fig. 1d the nozzle according to Fig. 1a, Fig. 1b und Fig. 1c in another perspective view; Fig. 2a a perspective view of a nozzle according to a second embodiment; Fig. 2b the nozzle according to Fig. 2a in a side view; Fig. 2c the nozzle according to Fig. 2a und Fig. 2b Top view; Fig. 2d the nozzle according to Fig. 2a, Fig. 2b und Fig. 2c in a further perspective view; Fig. 3 a schematic representation of a nozzle arrangement according to one aspect of the invention in an exemplary embodiment; Fig. 4a a side view of a nozzle and a nozzle holder for a nozzle arrangement according to Fig. 3 ; Fig. 4 leg perspective view of a nozzle holder according to Fig. 3 or Fig. 4a ; and Fig. 4 shows a perspective view of a nozzle according to Fig. 3 or Fig. 4a . Detailed description of the drawings

[0045] The described embodiments are merely examples that can be modified and / or supplemented in various ways within the scope of the claims. Each feature described for a particular embodiment can be used independently or in combination with other features in any other embodiment. Each feature described for an embodiment of a particular claim category can also be used accordingly in an embodiment of a different claim category.

[0046] The Figuren 1a bis 1d Figure 1 shows a first embodiment of a nozzle 1.1. The nozzle 1.1 comprises a first nozzle section 2.1 and a second nozzle section 2.2. The first nozzle section 2.1 is designed as a hollow truncated cone with a top surface 3.1 and a base surface 3.2 (shown partially obscured). A lateral surface 3.3 of the truncated cone tapers concavely from the base surface 3.2 to the top surface 3.1. The second nozzle section 2.2 is designed as a hollow cylinder and connects to the base surface 3.2 of the first nozzle section 2.1 with a top surface 4.1 (shown partially obscured). Furthermore, the second nozzle section 2.2 itself has a base surface 4.2 (shown partially obscured) and a lateral surface 4.3.

[0047] The nozzle 1.1 has a first through-pass that forms a first nozzle opening 5.1 in the cover surface 3.1 of the first nozzle section 2.1. Furthermore, the nozzle 1.1 has five second through-passes arranged on a circular path around the first through-pass and forming second nozzle openings 5.2 in the outer surface 3.3. The first through-pass has a through-pass axis that runs concentrically with a central axis 7 of the nozzle 1.1. Seven third through-passes, overlapping the first through-pass, are also formed on the first through-pass, creating a contour with grooves 6.1 on the inner walls of the first through-pass. The second through-passes have through-pass axes 9 that are each tilted relative to a parallel axis 8 parallel to the central axis 7 of the nozzle 1.1. The through-axis 9 of the second through-axis is perpendicular to the parallel axis 8 and the central axis 7 of the nozzle 1.The intersecting first transverse axis 10 is arranged tilted about a first tilting angle α. Furthermore, the through-passage axes 9 of the second through-passages are each arranged tilted about a second transverse axis 11, which is perpendicular to the parallel axis 8 and perpendicular to the first transverse axis 10, by a second tilting angle β. Fig. 1d The figure shows a view along the line of one of the second penetrations, from which the course of the penetration axis 9 of this second penetration can be seen in more detail. Furthermore, it is shown from Fig. 1a to recognize that the second penetrations 5.2 project radially into an inner surface of the second nozzle section 2.2 and form a contour with grooves 6.2 there.

[0048] The Figuren 2a bis 2d Figure 1.2 shows a second embodiment of a nozzle 1.2, which corresponds to nozzle 1.1 in its essential features and differs from nozzle 1.1 in particular in that it has seven instead of five secondary passages or secondary nozzle openings 5.2. The secondary passages have a reduced cross-section. Furthermore, nozzle 1.2 does not have any third passages. The first passage has a smooth inner wall. A repeated description of the similar features of nozzles 1.1 and 1.2 is omitted.

[0049] Figur 3 Figure 1 shows a schematic representation of a nozzle arrangement 20 with a pressure tank 21, a supply line 22 connected to the pressure tank 21, and two nozzles 1.3 and 1.4 arranged on the supply line 22. The nozzles 1.3 and 1.4 are arranged above cylindrical filter elements 12 and are oriented to clean an inner surface of the filter elements 12. The nozzle 1.3 is similar in its essential features to the nozzles 1.1 and 1.2 according to the Figuren 1a bis 2d The flow contour 13 is designed and therefore has a bundled flow contour 13, the diameter of which essentially corresponds to the inner diameter of the cylindrical filter element 12 and is thus particularly advantageous for shearing off a filter cake at the inner surface of the filter element 12. The helical shape of the flow contour 13 is indicated by corresponding directional arrows. Due to the bundling / constriction of the flow contour 13, the flow contour 13 is approximately stable over the entire length of the filter element 12. The nozzle 1.4, on the other hand, is not designed according to the invention, but according to the prior art and has a widely fanned-out flow contour 14 extending shortly behind the nozzle 1.4, by means of which targeted shearing off of a filter cake at the inner surface of the filter element 12 is only possible inadequately or with very high pressures in the pressure tank 21.

[0050] The Figuren 4a bis 4c Figure 1 shows the design of a nozzle 1.3 held on the supply line 22 by means of a nozzle holder 23, or the nozzle holder 23 and the nozzle 1.3 are shown separately. The nozzle holder 23 is designed as a bendable, clamp-shaped component and can be clamped to a round supply line 22 by means of connecting elements 24 designed as clamping elements. The nozzle holder 23 also has a receptacle 25 for the nozzle 1.3, which is formed on the one hand by a round recess 25.1 for inserting the nozzle 1.3 from an inner surface of the nozzle holder 23 and on the other hand by a hexagonal recess 25.2 for positive engagement with a collar 15 of the nozzle 1.3. The recess 25.2 and the collar 15 can also have any other geometries corresponding to each other for positive engagement.

[0051] The nozzle 1.3 has a collar 15 on its base 4.2 with a hexagonal outer contour for positive engagement with the recess 25.2. The collar 15 forms a recess 26 for contacting the outer surface of the supply line 22, such that when the nozzle 1.3 is inserted into the nozzle holder 23 from the inside, the collar 15 fits into the inner contour 23.1 of the nozzle holder 23. The nozzle 1.3 also has a projection 27 extending into this inner contour 23.1 of the nozzle holder 23, which surrounds an inlet opening 16 of the nozzle 1.3. As shown in Figur 4a As can be seen, the projection 27 extends into the nozzle holder 23 and is thus designed to engage in a supply opening (not shown) and thereby ensure the alignment of the inlet opening 16 with the supply opening or to center the openings on each other.

[0052] Overall, the nozzle 1.3 is held securely in position and against rotation on the nozzle holder 23. In particular, the nozzle 1.3 is held in the recess 25 by the supply line 22 when the nozzle holder 23 is mounted on the supply line 22. Reference symbol list

[0053] 1.1 Nozzle 1.2 Nozzle 1.3 Nozzle 1.4 Nozzle 2.1 First nozzle section 2.2 Second nozzle section 3.1 Top surface of the first nozzle section 3.2 Base surface of the first nozzle section 3.3 Shell surface of the first nozzle section 4.1 Top surface of the second nozzle section 4.2 Base surface of the second nozzle section 4.3 Shell surface of the second nozzle section 5.1 First nozzle opening 5.2 Second nozzle opening 6.1 Groove 6.2 Groove 7 Central axis of the nozzle 8 Parallel axis 9 Through-axis of the second through-axis 10 First transverse axis 11 Second transverse axis 12 Filter element 13 Flow contour 14 Flow contour 15 Collar 16 Inlet opening 20 Nozzle arrangement 21 Pressure tank 22 Supply line 23 Nozzle holder 24 Connecting element 25 Receptacle 25.1 Recess of the receptacle 25.2 Recess of the receptacle 26 Recess for contact with the outer surface of the supply line 27 Projection α First tilt angle β Second tilt angle

Claims

1. Nozzle assembly (20) for cleaning a filter element (12) by means of a fluid flow, comprising a tubular supply line (22) with a supply line opening in a shell surface of the supply line (22); at least one nozzle (1.1, 1.2, 1.3, 1.4) designed as a hollow body with a base surface (4.2), wherein the nozzle (1.1, 1.2, 1.3, 1.4) has an inlet opening (16) in the base surface (4.2); and at least one nozzle holder (23) with a receptacle (25) for the nozzle (1.1, 1.2, 1.3, 1.4); wherein the nozzle (1.1, 1.2, 1.3, 1.4) on the base surface (4.2) has a recess (26) for fitting to the shell surface of the supply line (22), such that the inlet opening (16) is against the supply line (22) and is aligned with the supply line opening; wherein the nozzle (1.1, 1.2, 1.3, 1.4) is detachably held and centered on the receptacle (25) of the nozzle holder (23) and the nozzle holder (23) is detachably held on the supply line; wherein the nozzle (1.1, 1.2, 1.3, 1.4) is held in a positive fit at the nozzle holder (23) and can be inserted into the recess (25) by an inner side of the nozzle holder (23) covered by the supply line (22); and wherein the nozzle (1.1, 1.2, 1.3, 1.4) is held through the supply line (22) in the recess (25) when the nozzle holder (23) is mounted on the supply line (22).

2. Nozzle assembly (20) according to claim 1, wherein the nozzle (1.1, 1.2, 1.3, 1.4) has a collar (15) and is held in a form-fit on the nozzle holder (23) by means of the collar (15).

3. Nozzle assembly (20) according to one of claims 1 or 2, wherein the nozzle holder (23) is held in a force-fit manner on the supply line (22) and in particular is connected in a clip-on form to the supply line (22).

4. Nozzle assembly (20) according to claim 3, wherein the nozzle holder (23) is designed to be hinged or bendable and is designed to be held in a folded / bent position by means of connecting means (24) and to be clamped onto the supply line (22).

5. Nozzle assembly (20) according to one of claims 1 to 4, wherein the nozzle (1.1, 1.2, 1.3, 1.4) has a projection (27) at the inlet opening (16) projecting into the supply opening.

6. Nozzle assembly (20) according to one of claims 1 to 5, wherein the nozzle (1.1, 1.2, 1.3) comprises: at least one first nozzle section (2.1) designed as hollow truncated cone; at least one first passage, wherein the first passage forms a first nozzle opening (5.1) in a cover surface (3.1) of the first nozzle section (2.1); and a plurality of second passages surrounding the first passage, wherein the second passages form second nozzle openings (5.2) in the shell surface (3.3) of the first nozzle section (2.1); wherein the second passages for imprinting a helical flow contour (13) onto the fluid flow each have a passage axis (9) tilted relative to a parallel axis (8) parallel to the central axis (7) of the nozzle (1.1, 1.2, 1.3).

7. Nozzle assembly (20) according to claim 6, wherein the second passages are arranged on a circular path concentric with the central axis (7) of the nozzle (1.1, 1.2, 1.3).

8. Nozzle assembly (20) according to claim 6 or 7, wherein the first nozzle section (2.1) has a concave tapered shell surface (3.3).

9. Nozzle assembly (20) according to one of claims 6 to 8, comprising a second nozzle section (2.2) designed as a hollow cylinder adjoining a base surface (3.2) of the first nozzle section (2.1), wherein in particular the second passages project radially outwards from the inside into an outer wall of the second nozzle section (2.2) to form a contour on an inner side of the outer wall.

10. Nozzle assembly (20) according to claim 9, wherein the second nozzle section (2.2) has a recess (26) on a base surface (4.2) for contact with a cylindrical contour extending at an angle to the central axis (7) of the nozzle (1.1, 1.2, 1.3) and in particular has a collar (15).

11. Nozzle assembly (20) according to one of claims 6 to 10, wherein the passage axes (9) of the second passages are each arranged tilted by a first tilt angle (α) about a first transverse axis (10) which is perpendicular to the parallel axis (8) and intersects the central axis (7) of the nozzle (1.1, 1.2, 1.3), wherein, in particular, the first angle of inclination (α) is 0 to 45°, and particularly preferably 23°.

12. Nozzle assembly (20) according to any one of claims 6 to 11, wherein the passage axes (9) of the second passages are each arranged at a second tilt angle (β) relative to a second transverse axis (11) which is perpendicular to the parallel axis (8) and perpendicular to the first transverse axis (10), wherein, in particular, the second tilt angle (β) is 0 to 90°, particularly preferably 45°.

13. Nozzle assembly (20) according to one of claims 6 to 12, wherein a taper ratio between an inlet cross-section and an outlet cross-section of the nozzle (1.1, 1.2, 1.3) is between 1:1 and 3:1.

14. Nozzle assembly (20) according to one of claims 6 to 13, wherein the first passage is round and has a diameter of 1 to 70% of a nozzle diameter and / or wherein the second passages are each round and have a diameter of 1 to 70% of the nozzle diameter.