FILTER ARRANGEMENT FOR AN AIR SUPPLY DEVICE, INCLUDING A METHOD FOR ITS MANUFACTURING, AND THE AIR SUPPLY DEVICE

Description

[0001] The invention relates to a filter arrangement for an air supply device, in particular for living spaces equipped with a (fireplace) stove, according to claim 1.

[0002] The invention also relates to an air supply device, in particular for living spaces, with a filter arrangement according to the invention, as per claim 9.

[0003] Furthermore, the invention with claim 15 relates to a method for manufacturing a filter arrangement, in particular the filter arrangement according to the invention.

[0004] Finally, a method for maintaining the air supply device according to the invention is also disclosed.

[0005] In the ventilation of living spaces, especially those with wood-burning stoves, state-of-the-art air supply systems are regularly used in which the intake air is at least coarsely cleaned by the use of filter materials such as filter wool, filter baskets, or the like. These filter materials are contained in corresponding filter arrangements, which, according to the state of the art, can be designed in various ways.

[0006] In a first known filter arrangement, a pocket filter is clamped with its opening edge between two profiled metal rings. The filter is clamped by the inner ring, to which bent wires for assembly and disassembly are welded. A seal is attached below the outer ring. The entire assembly is placed on the crimped end of an intake tower, which forms an end section of the air supply system.

[0007] Besides this well-known concept, numerous other solutions exist on the market for securing the filter material, including clamping rings or filter baskets. The clamping ring presses the filter material against the outer wall of a pipe, while with the filter basket, the filter material is pulled onto the basket and secured under the seal within a groove on the filter basket.

[0008] While the use of clamping rings according to the state of the art is cost-effective, it disadvantageously offers no sealing and also does not guarantee the safe and permanently exact positioning in the air supply device, e.g. in a relevant ventilation pipe.

[0009] The filter basket requires a complex and correspondingly expensive manufacturing process for its geometry. The aforementioned seal must also be removed when the filter is replaced (a regularly required step), which complicates handling and incurs further costs.

[0010] The aforementioned double clamping rings involve a complex and therefore expensive manufacturing process because two molded parts are required. Handling is complicated by the time-consuming process of threading the filter material by an assembly worker and the additional need to apply plastic coatings to the wires. EP 179 746 B1, US 4 783 321 A, EP 2 404 567 A1 and US 7 381 385 B2 are relevant prior art documents.

[0011] The invention is based on the objective of creating a simplified, more cost-effective, durable, and yet high-quality technical solution, particularly with regard to the achievable tightness, with which a filter arrangement of the type outlined above can be provided. Furthermore, an air supply device, especially for residential spaces, a method for manufacturing a filter arrangement, and a method for maintaining the air supply device, all characterized by the same advantages, are to be specified.

[0012] In particular, maintenance should be made easier and – if the air supply device has an air intake hood with a removable cover – it should also be possible to replace the filter assembly or the filter material without removing the entire hood.

[0013] The problem is solved by a filter arrangement having the features of claim 1, by an air supply device having the features of claim 9, by a method for manufacturing a filter arrangement having the features of claim 15 and by the further disclosed method for maintaining the air supply device.

[0014] Advantageous embodiments of the invention are defined in the respective dependent claims.

[0015] A filter arrangement according to the invention for an air supply device comprises: a clamping ring made of sheet metal, e.g., (stainless) steel; a sealing ring; and a filter element made of filter material. The clamping ring has a base body and, distributed around its outer circumference, a plurality of first radial projections that extend from the base body and are bent (i.e., formed) radially inward so that they extend parallel to a plane of the base body and are each arranged at a finite distance from the base body. The sealing ring is attached concentrically to the base body. Preferably, the sealing ring and the base body have substantially the same (free) opening cross-sections.The filter part has a pocket or pouch shape with an opening and is held clamped by an edge area of ​​the opening between the base body and the bent-back first radial projections, from which the term "clamping ring" is derived.

[0016] The filter arrangement according to the present invention therefore consists of only three parts, namely the sealing ring, the clamping ring and the filter part (pocket filter).

[0017] The sealing ring can preferably consist of a PUR foam which has a self-adhesive surface and can therefore be applied easily and precisely to the clamping ring.

[0018] The sealing ring ensures, firstly, that the drawn-in outside air is actually directed through the filter material and does not bypass it. Secondly, a preferably (slightly) larger diameter of the elastically deformable sealing ring (compared to the inner diameter of a pipe or air duct element housing the filter assembly) can also provide additional tension and precise positioning.

[0019] An air supply device according to the invention, in particular for living spaces, has a filter arrangement according to the invention, as sketched above, and at least one tubular air supply element, wherein the filter arrangement is removablely inserted into the air supply device.

[0020] With appropriate further training, the air supply device can have a terminal intake hood that is fluidly connected to the air guide element.

[0021] The intake hood or air guide element itself can be designed in such a way that it / it catches the filter assembly by means of a pronounced groove or at least some other projection.

[0022] The clamping ring can preferably be designed such that it secures the pocket filter or filter element by bending over – without limitation – four tabs (corresponding to the aforementioned first radial projections). Additional hooks or retaining projections or points can ensure that the filter element cannot slip after the tabs have been bent over.

[0023] Furthermore, two tabs or handle parts can be attached or molded onto the inside of the clamping ring – without restriction – which can be bent over and gripped, thus enabling a smooth replacement of the filter by a specialist.

[0024] The clamping ring is preferably manufactured from a single piece and requires no further processing steps.

[0025] The pocket filter or bag filter is a standard filter component that is well-known in itself.

[0026] A method according to the invention for manufacturing a filter arrangement, in particular the filter arrangement according to the invention, comprises the steps: a) Providing a clamping ring made of sheet metal material, comprising a base body and a plurality of first radial projections distributed around its outer circumference, which extend from the base body; b) Providing a sealing ring; and c) Providing a pocket- or bag-shaped filter part made of filter material with an opening; d) Arranging the filter part on the clamping ring so that an edge of the opening rests fully against the base body; e) Bending the first radial projections radially inwards onto the side of the clamping ring against which the filter part rests, so that they extend parallel to a plane of the base body and each clamp a section of the edge of the opening of the filter part against the base body; f) Concentrically attaching the sealing ring to the base body.

[0027] A method for maintaining the air supply device according to the invention includes the following steps: i) If necessary, remove the cover; ii) remove the filter assembly from the air supply unit, in particular by grasping the handle; iii) bend open the first radial projections to release the clamping of the filter part; iv) remove and replace the filter part; v) step d) and step e), as defined above; vi) insert the filter assembly into the air supply unit, if necessary by grasping the handle; vii) if necessary, (re-)attach the cover.

[0028] The following specific embodiments of the invention have proven to be particularly advantageous from the applicant's point of view: In a first further development of the filter arrangement according to the invention, the clamping ring can be manufactured from the sheet metal material by laser cutting, water jet cutting or by punching.

[0029] This greatly simplifies and reduces the cost of production, because basically only a single process step is required.

[0030] In another embodiment of the filter arrangement according to the invention, the first radial projections can be reversibly bent outwards and inwards and backwards.

[0031] Reversible means that this process can be repeated multiple times without damaging the clamping ring. It can therefore be reused several times when the filter material is replaced, which is particularly sustainable.

[0032] In yet another embodiment of the filter arrangement according to the invention, at least some of the first radial projections can have a number of first retaining projections, preferably retaining tips, for the filter part on their outer sides facing away from the base body.

[0033] This ensures that the filter part can no longer slip after the first radial projections have been bent over, as has already been pointed out.

[0034] In yet another embodiment of the filter arrangement according to the invention, the clamping ring can have a number of second retaining projections, preferably retaining tips, for the filter part distributed over an inner circumference of the base body.

[0035] This further enhances the described effect, whereby the filter part can no longer slip after the first radial projections have been bent over.

[0036] In another advantageous embodiment of the filter arrangement according to the invention, the second retaining projections can be arranged in circumferential areas that correspond to those circumferential areas in which the first radial projections are also formed.

[0037] The applicant has discovered that this method makes the holding effect on the filter part particularly favorable.

[0038] In another particularly advantageous embodiment of the filter arrangement according to the invention, the clamping ring can have at least one handle part, preferably integrally molded, or preferably two diametrically opposed handle parts, on the inner circumference of the base body. The handle part can preferably be bent out of the aforementioned plane or be bendable out of it, and in particular, after being bent out, extend substantially perpendicular to the plane and away from the base body.

[0039] It has already been pointed out that such a handle greatly facilitates the handling of the filter assembly, especially when a replacement is required for maintenance purposes.

[0040] In another particularly advantageous embodiment of the filter arrangement according to the invention, the clamping ring can have a plurality of second radial projections distributed around the outer circumference of the base body, which project from the base body. At least some of these second radial projections can be angled approximately perpendicular to the aforementioned plane, i.e., deformed, and in particular on the same side as the first radial projections.

[0041] The second radial projections can serve two purposes: firstly, if they are not angled, they can be used to place the filter assembly on the axial end face or surface of an air duct element; secondly, if angled, they can be used to center the filter assembly within an air duct element. This further improves the operational reliability of the filter assembly.

[0042] To fully achieve its sealing effect, in another embodiment of the filter arrangement according to the invention, the sealing ring can be made of a closed-cell foam material, in particular PUR (polyurethane) or EPDM (ethylene propylene diene monomer rubber). However, the invention is not limited to a specific material selection in this respect; all sealing materials with comparable properties can be advantageously used.

[0043] The manufacture of the filter arrangement is particularly simple if, in yet another embodiment of the filter arrangement according to the invention, the sealing ring is glued to the base body with an adhesive side.

[0044] The manufacture of the filter arrangement is simplified even further if, in yet another embodiment of the filter arrangement according to the invention, the sealing ring is designed to be self-adhesive on the adhesive side.

[0045] It has therefore proven particularly advantageous if, in one embodiment of the filter arrangement according to the invention, the sealing ring is arranged on a side of the base body facing away from the bent-back first radial projections, because this side is particularly smooth or flat and therefore facilitates the attachment of the sealing ring.

[0046] However, in certain embodiments of the filter arrangement according to the invention, it may be advantageous, particularly when the aforementioned second radial projections are provided, to arrange the sealing ring on the same side of the base body as the bent-back first radial projections, so that the sealing ring can find its place within the air guide element as intended.

[0047] In yet another embodiment of the filter arrangement according to the invention, the sealing ring has an excess in the radial direction compared to the clamping ring, preferably with the exception of the non-angled second radial projections, preferably completely.

[0048] This increases the sealing effect and can also create a centering effect, as has already been mentioned.

[0049] In one embodiment of the air supply device according to the invention, it can be provided that the filter arrangement is at least partially arranged in the air guide element.

[0050] Such an arrangement is particularly suitable if the air supply system does not have a separate intake hood.

[0051] However, in one embodiment of the air supply device according to the invention, it can be provided that it has a terminal intake hood which is fluidly connected to the air guide element.

[0052] Such an intake hood can have numerous air inlets or air inlet slots and advantageously seals off the air supply system on the outside of the building against weather influences.

[0053] With a corresponding embodiment of the air supply device according to the invention, it can then be provided that the filter arrangement is at least partially arranged in the intake hood, which can facilitate accessibility.

[0054] In particular, if the intake hood has an opening with a removable cover that closes the opening, through which the filter assembly can be removed and inserted, the insertion and replacement of the filter assembly can be greatly simplified.

[0055] In another embodiment of the air supply device according to the invention, the filter arrangement can be fixed or fixable within the air supply device by providing the air supply device with a number of inwardly directed support projections in the area of ​​the air guide element or, if present, in the area of ​​the intake hood. These projections can be designed, in particular, as a continuous circumferential support projection, e.g., in the form of a groove or a crimped edge. The filter arrangement can rest on these projections / projections in an edge region of the base body.

[0056] Thus, a simple way is created to determine the filter arrangement within the air supply device according to the invention, preferably solely by the effect of gravity, if the support projections are arranged appropriately.

[0057] In yet another embodiment of the air supply device according to the invention, it can further be provided that the filter arrangement is fixed or definable in the air supply device by having a support surface, in particular an end-face support surface, e.g., a terminal cut edge, in the area of ​​the air guide element or, if present, in the area of ​​the intake hood. The filter arrangement can then rest on or against the aforementioned support surface with its non-angled second radial projections.

[0058] Compared to the solution described above, this can offer the advantage that no additional formation of support projections is required, because practically every air guide element already includes such a (front-facing) support surface.

[0059] It has already been pointed out that, with a corresponding design of the air supply device according to the invention, the filter arrangement can be centered by the sealing ring and / or, if present, by the angled second radial projections in the air supply device.

[0060] In summary, the present invention offers the following advantages in particular: reduction of the required variety of tools, reduction of manufacturing steps and thus cost-effective production, guarantee of tightness, and easy assembly / disassembly or easy replacement of the filter part or material.

[0061] Further features and advantages of the invention will become apparent from the following description of exemplary embodiments with reference to the drawing. Figure 1 shows a first embodiment of the clamping ring; Figure 2 shows the clamping ring Figure 1with radially inwardly bent first radial projections; Figure 3 shows a second embodiment of the clamping ring; Figure 4 shows the clamping ring Figure 3 with radially inwardly bent first radial projections and handle parts bent out of a plane of the clamping ring; Figure 5 shows the use of a filter arrangement according to the invention in an air supply device in a partial exploded view; Figure 6 shows the elements from Figure 5 in a composite state and in a sectional view; Figure 7 shows a close-up section from Figure 6 ; Figure 8 shows a close-up section from Figure 6 in perspective representation; Figure 9 shows a close-up section from Figure 8 ; and Figure 10 shows a slightly modified design of the clamping ring made of Figure 3 and its preferred use.

[0062] In all figures, the same reference symbols denote identical or at least equivalent elements.

[0063] In the Figure 1 A first embodiment of a clamping ring 1 is shown, as it can be used in a filter arrangement according to the invention for an air supply device.

[0064] The clamping ring 1 is in the Figure 1 shown in its undeformed delivery state; it is manufactured as a simple flame-cut, cut or stamped part from sheet metal, e.g. from (stainless) steel.

[0065] The clamping ring 1 has a flat base body 1a, which has a plurality of radial projections 1b distributed around its outer circumference, projecting from the base body. The radial projections 1b are bendable radially inwards (cf. Figure 2), so that they then (i.e., after the transformation) extend in particular parallel to a plane of the base body 1a. For the purpose of simplified bending, the base body 1a may have recesses 1c laterally to the projections 1b. The free ends of the projections 1b may be rounded, as shown.

[0066] After the aforementioned bending / shaping, the projections 1b extend as shown in the Figure 2 It can be seen that they are parallel to the aforementioned plane of the base body 1a and each has a (small) finite distance A to the base body 1a, as can be seen in particular from the Figures 7-9 removes, although these show a slightly different design of the clamping ring 1. Between the bent-back projections 1b and the base body 1a, a filter material or a filter part (not shown) can be clamped and held in place in the area of ​​distance A, which will be discussed in more detail below.

[0067] Due to the choice of material for the clamping ring, the projections 1b can be bent back and forth several times without being damaged, so that the clamping effect mentioned can be reproduced (any number of times).

[0068] The Figures 3 and 4 Figure 1 shows two views of a slightly differently designed clamping ring 1'. This ring additionally features a number of second retaining projections 1d' distributed around an inner circumference of the base body 1a, which are designed as retaining points for the filter part (not shown). The second retaining projections 1d' are arranged in circumferential regions that correspond to those circumferential regions in which the first radial projections 1b' are also formed. The latter differ slightly from the design shown in the figures. Figure 1 and 2formed, on the one hand wider (in circumferential direction) and on the other hand by adding further retaining projections or retaining tips 1e' for the filter part (not shown), which are arranged on the outer sides of the first radial projections 1b' facing away from the base body 1a.

[0069] The invention is not limited, in particular with regard to the number and shape of the retaining projections 1d', 1e'.

[0070] Furthermore, the clamping ring 1' has two integrally molded handle parts 1f on the inner circumference of its base body 1a, each with an engagement opening 1g, which are preferably bendable out of the plane of the base body 1a, as can be seen especially in the Figure 4 recognizes. After bending outwards, the handle parts 1f extend essentially perpendicular to the aforementioned plane and away from the base body 1a. According to the Figure 4 are also the first radial projections 1b' starting from the delivery state in Figure 3reshaped radially inwards, as discussed above. Figure 2 described.

[0071] In the Figure 5 The illustration shows how a filter arrangement according to the invention is used for an air supply device as intended. The filter arrangement is designated by reference numeral 2 and comprises, in addition to the clamping ring 1' (see figure 1), the following: Figures 3 and 4 ) also a sealing ring 3 and a filter part 4, which has already been mentioned several times.

[0072] The sealing ring 3, which may be made of a closed-cell foam material, in particular PUR or EPDM, is concentrically attached, preferably glued, to the base body 1a of the clamping ring 1', specifically on a side facing away from the bent-back first radial projections 1b'. The filter part 4 consists of a suitable air filter material, e.g., filter wool or a nonwoven material, and has a pocket or bag shape with an opening 4a. It is held clamped between the base body 1a and the bent-back first radial projections 1b' by means of an edge region of this opening 4a, which in the Figures 7 to 9 This can be seen even more clearly. The pocket shape of the filter part 4 extends towards the side facing away from the sealing ring 3.

[0073] The air supply system is located in the Figure 5Designated by reference numeral 5, it comprises a terminal intake hood 6, which is fluidly connected to a tubular air guide element 7. The intake hood 6 includes a removable cover 8 and a circumferential air intake grille (not visible here), which is covered by louvers in the form of frustoconical ring segments 9. The cover closes an (upper) opening 10 of the intake hood 6.

[0074] The following procedure is used in particular to manufacture the filter assembly 2: a) Providing the clamping ring 1'; b) Providing the sealing ring 3; and c) Providing the pocket- or bag-shaped filter part 4; d) Arranging the filter part 4 on the clamping ring 1' so that the edge of the opening 4a rests fully against the base body 1a; e) Bending back the first radial projections 1b' radially inwards onto the side of the clamping ring 1' against which the filter part 4 rests, so that they extend parallel to a plane of the base body 1a and each clamp a section of the edge of the opening 4a of the filter part 4 against the base body 1a; f) Concentrically attaching the sealing ring 3 to the base body 1a.

[0075] The filter part 4, or the completed filter assembly 2, is then inserted into the air supply device 5 through the opening 10 in the intake hood 6 in the direction of arrow P by grasping the handle parts 1f of the clamping ring 1' with the pocket or bag shape leading, and the air supply device 5 is then closed using the cover 8. The procedure is reversed when removing the filter part 4.

[0076] Figure 6 shows in a longitudinal section through the (composite) air supply device 5 Figure 5The filter element 4 is arranged within the air supply device 5. The air guide element 7 is only partially shown here (dashed lines). The clamping ring 1' rests with its underside facing away from the sealing ring 3 on a circumferential, radially inwardly projecting groove 11 or a similarly projecting structure, e.g., a crimped edge, which is formed in a lower area of ​​the intake hood 6 below the air intake grille 6a. The groove 11 or the projection need not be continuous; several grooves or projections are also possible.

[0077] The elastically deformable sealing ring 3 preferably has a (slight) interference of approximately 1 mm with respect to the clear inner diameter ID of the intake hood 6 and with respect to the clamping ring 1'. This can ensure a particularly good seal and also have a centering effect.

[0078] To remove the filter assembly 2, grasp the handle parts 1f and remove the filter assembly 2 in the direction of arrow P' (after removing the lid 8).

[0079] Accordingly, the maintenance of the air supply device 5 is preferably carried out as follows: i) Removing the cover 8; ii) Removing the filter assembly 2 from the air supply unit 5 by grasping the handle parts 1f; iii) Bending open the first radial projections 1b' to release the clamping of the filter part 4; iv) Removing and replacing the filter part; v) Step d) and step e) according to the procedure used in the manufacture of the filter assembly 2; vi) Inserting the filter assembly 2 into the air supply unit 5 by grasping the handle parts 1f; vii) Attaching the cover 8.

[0080] Figure 7 shows a detailed enlargement from Figure 6(without the air guide element 7). Here, one can clearly see, firstly, the previously mentioned distance A and the clamping of the filter part 4 with the edge of its opening 4a between the base body 1a and the bent projections 1b' of the clamping ring 1', and secondly, the groove 11 on which the clamping ring 1' rests. The aforementioned interference is also indicated schematically (at reference numeral B).

[0081] Figure 8 shows the same object as the Figure 7 From a slightly different perspective, it is clearly visible how the retaining tips 1d', 1e' of the clamping ring 1' partially engage in the (filter) material of the filter part 4 to ensure improved retention. Since the filter part 4 neither gets wet nor is subjected to substantial axial stress, there is no risk of the filter material tearing.

[0082] Figure 9 shows a further detailed magnification based on the Figure 8The excess of the sealing ring 3 is clearly visible here at B (in reality, the wall 6b of the intake hood 6 compresses the material of the sealing ring 3, which is of course completely located inside the intake hood 6 - unlike the present conceptual representation).

[0083] In the Figure 10 It is shown that the clamping ring 1" (here without filter part) can also be held in the air supply device 5 in a different manner according to one variant. In the variant shown, the clamping ring 1" has a plurality of second radial projections 1h distributed around the outer circumference of the base body 1a, which project from the base body and of which at least some are angled approximately perpendicular to the aforementioned plane, i.e., bent, in particular to the same side as the first radial projections 1b'.

[0084] More precisely, groups of (without limitation) five second radial projections 1h are always provided, every second of which is angled downwards by approximately 90 degrees to the plane of the base body 1a. These angled second radial projections 1h ensure that the filter assembly or the clamping ring 1" is clamped and / or centered in the air guide element 7 shown, while the non-angled second radial projections 1h ensure that the filter assembly or the clamping ring 1" rests on a bearing surface, in particular an end-face bearing surface 7a, of the air guide element 7.

[0085] In this embodiment, the sealing ring (not shown) is preferably arranged below the clamping ring 1", i.e. on the same side as the bent first radial projections 1b' and thus within the air guide element 7.

[0086] As the expert can easily recognize, the ones in the Figures 3-10The further developments shown, in particular in connection with the retaining tips and / or the second radial projections, can also be readily implemented starting from the clamping ring 1 according to the Figure 1 and 2 feasible.

Claims

1. Filter arrangement (2) for an air supply device (5), having: a clamping ring (1, 1', 1") made of a sheet metal material; a sealing ring (2); and a filter component (4) made of a filter material; in which the clamping ring (1, 1', 1") has a base body (1a) and in a state distributed over the outer circumference thereof a plurality of first radial projections (1b, 1b') which protrude from the base body (1a), are bent back radially inwardly so that they extend parallel with a plane of the base body (1a) and are in each case arranged with a finite spacing (A) with respect to the base body (1a); in which the sealing ring (3) is secured concentrically to the base body (1a); and in which the filter component (4) has a pocket or bag form with an opening (4a) and is retained in a clamping manner with an edge region of the opening (4a) between the base body (1a) and the bent-back first radial projections (1b, 1b').

2. Filter arrangement (2) according to claim 1, in which the first radial projections (1b, 1b') can be bent back and forth outwards and inwards in a reversible manner.

3. Filter arrangement (2) according to any one of the preceding claims, in which at least some of the first radial projections (1b') have a number of first retention projections (1e'), preferably retention tips (1e'), for the filter component (4) at the outer sides thereof facing away from the base body (1a).

4. Filter arrangement (2) according to any one of the preceding claims, in which the clamping ring (1' , 1") has a number of second retention projections (1d'), preferably retention tips (1d'), for the filter component (4) in a state distributed over an inner circumference of the base body (1a).

5. Filter arrangement (2) according to claim 3 and claim 4, in which the second retention projections (1d') are arranged in circumferential regions which correspond to those circumferential regions in which the first radial projections (1b') are also formed.

6. Filter arrangement (2) according to any one of the preceding claims, in which the clamping ring (1") has, in a state distributed over the outer circumference of the base body (1a), a plurality of second radial projections (1h) which protrude from the base body (1a) and of which at least some are bent approximately at right-angles with respect to the mentioned plane, in particular with respect to the same side as the first radial projections (1b').

7. Filter arrangement (2) according to any one of the preceding claims, in which the sealing ring (3) is arranged at a side of the base body (1a) facing away from the bent-back first radial projections (1b') or, in particular with reference back to claim 6, at the same side of the base body (1a) as the bent-back first radial projections (1b').

8. Filter arrangement (2) according to any one of the preceding claims, in which the sealing ring (3) has, with respect to the clamping ring (1'), preferably with the exception of the non-bent second radial projections (1h) according to claim 6, an excess dimension in a radial direction, preferably completely circumferentially.

9. Air supply device (5), in particular for living spaces, having a filter arrangement (2) according to any one of the preceding claims and having at least one tubular air guiding element (7) in which the filter arrangement (2) is removably inserted, wherein the filter arrangement (2) is preferably arranged at least partially in the air guiding element (7).

10. Air supply device (5) according to claim 9 having a terminal extraction hood (6) which is connected to the air guiding element (7) for guiding fluid, wherein the filter arrangement (2) is preferably at least partially arranged in the extraction hood (6).

11. Air supply device (5) according to claim 10, in which the extraction hood (6) has an opening (10) having a removable cover (8) which closes the opening (10) and through which the filter arrangement (2) can be removed and inserted.

12. Air supply device (5) according to any one of claims 9 to 11, in which the filter arrangement (2) is or can be secured in the air supply device (5) by the air supply device (5) having in the region of the air guiding element (7) or, with reference at least to claim 10, in the region of the extraction hood (6) a number of inwardly directed support projections, in particular a continuously circumferential support projection (11), for example, in the form of a bead (11) or a flanged edge on which the filter arrangement (2) rests in an edge region of the base body (1a).

13. Air supply device (5) according to any one of claims 9 to 11, in which the filter arrangement (2) is or can be secured in the air supply device (5) by the air supply device (5) having in the region of the air guiding element (7) or, with reference at least to claim 10, in the region of the extraction hood (6) a support face (7a), in particular a front support face (7a), and the filter arrangement (2) with reference back to claim 6, resting with the non-bent second radial projections (1h) on the mentioned support face (7a).

14. Air supply device (5) according to any one of claims 9 to 13, in which the filter arrangement (2) is centered by the sealing ring (3) and / or, with reference back to claim 6, by the bent, second radial projections (1h) in the air supply device (5).

15. Method for producing a filter arrangement (2), in particular the filter arrangement (2) according to any one of claims 1 to 8, having the steps of: a) providing a clamping ring (1, 1', 1") made of a sheet metal material which has a base body (1a) and in a state distributed over the outer circumference thereof a plurality of first radial projections (1b, 1b') which protrude from the base body (1a); b) providing a sealing ring (3); and c) providing a pocket-like or bag-like filter component (4) made of a filter material having an opening (4a); d) arranging the filter component (4) on the clamping ring (1, 1', 1") so that an edge of the opening (4a) bears completely circumferentially on the base body (1a) in a planar manner; e) bending back the first radial projections (1b, 1b') radially inwardly at that side of the clamping ring (1, 1', 1"), on which the filter component (4) bears so that they extend parallel with a plane of the base body (1a) and in each case retain a portion of the edge of the opening (4a) of the filter component (4) in a clamping manner against the base body (1a); f) concentrically fitting the sealing ring (3) to the base body (1a).