FILTER WITH COMMUNICATOR

Abstract

The invention relates inter alia to a device (10) for filtering air flows, comprising a filter frame (22), an exchangeable filter nonwoven (23) and a holding device (24) by means of which the filter nonwoven can be held in place on the filter frame. A special feature of the invention is inter alia that the filter nonwoven is compressed and is arranged in a transport packaging (30) particularly in a vacuumized state.

Claims

1. An apparatus for filtering air flows, comprising a filter frame, a replaceable filter fleece, and a retaining device that can fix the filter fleece to the filter frame, wherein the filter fleece is in transport packaging so as to be compressed and evacuated.

2. A filter fleece for an apparatus for filtering air flows apparatus according to claim 1, wherein the filter fleece is in transport packaging so as to be compressed and evacuated.

3. A plurality of filter fleeces according to claim 2, wherein the plurality of filter fleeces are together surrounded by evacuated transport packaging.

4. A plurality of filter fleeces according to claim 2, wherein the individual filter fleeces of the plurality of filter fleeces are each individually surrounded by evacuated transport packaging and are fastened to one another.

5. A method of providing at least one filter fleece for an air filter according to claim 2, comprising the following steps: a) producing a filter fleece, b) surrounding the filter fleece with transport packaging such that the filter fleece can be stored and transported in a compressed manner and under vacuum, c) transporting the compressed fleece surrounded by the transport packaging to the point of use, and opening the transport packaging.

6. An apparatus for filtering air flows , according to claim 1, comprising a filter frame and a replaceable filter fleece, wherein the filter fleece can be detachably fixed to the filter frame, by a retaining device, wherein a sensor is on the filter frame or on the filter fleece or on a retaining device for the filter fleece.

7. The apparatus according to claim 6, wherein a property of the filter fleece can be detected and/or determined by the sensor.

8. The apparatus according to claim 6, wherein a property of a replaced filter fleece that has been or is to be reattached to the filter frame can be detected and/or determined by the sensor.

9. The apparatus according to claim 6, wherein a status of the filter fleece can be detected and/or determined by the sensor.

10. The apparatus according to claim 6, wherein information can be transmitted to a controller of a system for filtering air flows by the sensor and/or with the aid of the sensor.

11. The apparatus according to claim 6, wherein the sensor is securely on the filter frame.

12. The apparatus according to claim 6, wherein the sensor remains in an arrangement position on the filter frame while a filter fleece is being replaced.

13. The apparatus for filtering air flows according to claim 1, comprising a filter frame and a filter fleece arranged, detachably arranged, on the filter frame, wherein a sensor is on the filter frame or on the filter fleece or on a retaining device for the filter fleece, for detecting and/or determining sensor information regarding a property of the filter fleece.

14. The apparatus according to claim 13, wherein a memory element, in which the information regarding the property of the filter fleece can be stored, is assigned to the sensor.

15. The apparatus according to claim 13, wherein a status of the filter fleece, level of soiling or a service life of the filter fleece, can be determined by the sensor.

16. The apparatus according to claim 13, wherein information can be transferred to a controller of a system for filtering air flows by the sensor.

17. The apparatus according to claim 13, wherein the filter fleece is designed to be replaceable.

18. The apparatus according to claim 13, wherein the information regarding the property of the filter fleece can be automatically determined.

19. A filter fleece for arranging on a device for filtering air flows according to claim 1, wherein an information carrier is on the filter fleece which directly or indirectly carries information regarding a property of the filter fleece.

20. The filter fleece according to claim 19, wherein the information on and/or from the information carrier can be read out by a sensor which is on a filter frame of an apparatus for filtering air flows.

21. The apparatus according to claim 1, comprising a filter frame and a filter fleece detachably arranged, on the filter frame, wherein a sensor is on the filter frame or on the filter fleece or on a retaining device for the filter fleece for transmitting sensor information regarding a property of the filter fleece.

22. A system for filtering air flows, comprising a recirculating apparatus, an air inlet and an air outlet, wherein a plurality of air filters are provided which each comprise a filter frame, a sensor, which is on the filter frame or on the filter fleece or on a retaining device for the filter fleece, and a filter fleece, wherein a controller is provided to which an apparatus for documentation is assigned, wherein information from the sensors regarding the inserted filter fleeces can be received by the controller for forwarding to the apparatus.

23. The system according to claim 22, wherein the information includes information regarding the filter fleeces on the filter frame and/or information regarding the service lives of the inserted filter fleeces.

24. The system for filtering air flows according to claim 22, comprising a recirculating apparatus, an air inlet and an air outlet, wherein a plurality of air filters are provided which each comprise a filter frame and a filter fleece, wherein a controller is provided which manages information regarding the air filters and/or inserted filter fleeces, wherein the information includes position data regarding the air filters and/or position data regarding the inserted filter fleeces.

25. System according to claim 24, wherein the information includes data regarding properties of the filter fleeces on the filter frame and/or data regarding the service lives of the inserted filter fleeces.

26. The apparatus for filtering air flows according to claim 1, comprising a filter frame and a filter fleece detachably arranged, on the filter frame, wherein an apparatus is on the filter frame or on the filter fleece or on a retaining device for the filter fleece for detecting and/or determining and/or storing, and/or determining position data regarding the point of use of the inserted filter fleeces and for assigning position information assigned to a filter frame and/or filter fleece.

27. The apparatus for filtering air flows according to claim 1, comprising a filter frame and a filter fleece detachably arranged on the filter frame, wherein an apparatus is on the filter frame or on the filter fleece or on a retaining apparatus for the filter fleece for displaying and/or retrieving apparatus information regarding the status of the filter fleece.

28. The apparatus according to claim 27, wherein the information regarding the status of the filter fleece can be retrieved and/or displayed on demand or automatically.

29. The apparatus according to claim 27 or 28, wherein the information regarding the status of the filter fleece can be measured and/or detected and/or determined and/or received and/or stored and/or transmitted by the apparatus.

30. The apparatus for filtering air flows according to claim 1, comprising a filter frame and a filter fleece detachably arranged, on the filter frame, wherein an apparatus is on the filter frame or on the filter fleece or on a retaining device for the filter fleece for determining apparatus information regarding the status of the filter fleece, wherein an inner circumferential contour of the filter frame defines a clear width of the filter fleece through which an air flow can pass, wherein the apparatus comprises a voltage source and electronic components which are outside the inner circumferential contour, and a measuring head, which projects inwards beyond the inner circumferential contour and/or is within the inner circumferential contour.

31. The apparatus according to claim 30, wherein the measuring head is on a retaining device for the filter fleece.

32. The apparatus according to claim 31, wherein the measuring head is approximately centrally within the inner circumferential contour of the filter frame.

33. The apparatus for filtering air flows according to claim 1, comprising a filter frame and a filter fleece on the filter frame, wherein an apparatus is on the filter frame or on the filter fleece or on a retaining device for the filter fleece for measuring apparatus information regarding the status of the filter fleece.

Description

[0151] Other advantages become apparent from the dependent claims, which have not been cited, as well as from the following description of the embodiments shown in the drawings, in which:

[0152] FIG. 1 is a schematic, perspective, partially sectional view of a building comprising an embodiment of a system according to the invention for filtering air flows,

[0153] FIG. 2 is a schematic diagram for explaining the air flows in a system according to the invention for filtering air flows comprising two air filters shown by way of example,

[0154] FIG. 3 is a perspective schematic view of an apparatus according to the invention for filtering air flows, comprising a filter frame, a replaceable filter fleece, and a retaining device, as well as a rotatable latch element in a closed position,

[0155] FIG. 4 is an exploded view of the air filter from FIG. 3,

[0156] FIG. 5 shows a plurality of filter fleeces beside one another in a non-compressed state,

[0157] FIG. 6 shows the plurality of filter fleeces according to FIG. 5 in a compressed state, surrounded by evacuated transport packaging according to the invention,

[0158] FIG. 7 shows a single compressed filter fleece surrounded by evacuated transport packaging, according to the invention,

[0159] FIG. 8 shows a plurality of filter fleeces which are each individually surrounded by evacuated transport packaging according to the invention, and are fastened to one another by a retaining device,

[0160] FIG. 9 shows another embodiment of an apparatus according to the invention for filtering air flows in a view according to FIG. 3, with a sensor being on the filter frame,

[0161] FIG. 10 is a schematic exploded view, similar to FIG. 4, of the embodiment from FIG. 9,

[0162] FIG. 11 shows an embodiment of an apparatus according to the invention comprising a sensor for detecting information regarding a property of the filter fleece, in a view according to FIG. 3,

[0163] FIG. 12 is an exploded view of the embodiment from FIG. 11,

[0164] FIG. 13 shows an embodiment of an apparatus according to the invention, which comprises a sensor for transmitting information to a controller of a system (not shown in detail) according to the invention for filtering air flows, in a view comparable to FIG. 3,

[0165] FIG. 14 is an exploded view of the embodiment from FIG. 13,

[0166] FIG. 15 shows an embodiment of an apparatus according to the invention comprising a sensor for determining a status of the filter fleece, in a view according to FIG. 3,

[0167] FIG. 16 is an exploded view of the embodiment from FIG. 15,

[0168] FIG. 17 shows an embodiment of an apparatus according to the invention in a view according to FIG. 3, with a sensor being on the apparatus for transmitting information regarding a property of the filter fleece to a controller of a system for filtering air flows,

[0169] FIG. 18 shows an embodiment of system according to the invention in a view according to FIG. 1 in an arrangement within a building, wherein information can be transmitted from an apparatus on the air filters to a controller of the system, wherein the information can include data regarding properties of the filter or filter fleece and/or information regarding the status of the filter or filter fleece and/or can include information which can include position data for the filter or filter fleece,

[0170] FIG. 19 shows an embodiment of a system according to the invention in a view according to FIG. 18, wherein the controller of the system receives position data from a plurality of different air filters,

[0171] FIG. 20 shows another embodiment of an apparatus according to the invention in a view according to FIG. 3, wherein an apparatus which can receive information from a portable handset or transmit information thereto is on a filter frame of the apparatus,

[0172] FIG. 21 shows an embodiment of an apparatus according to the invention in a view according to FIG. 3, wherein a display apparatus that displays or communicates information regarding the status of the filter or filter fleece or keeps the information available for retrieval is on the apparatus, and

[0173] FIG. 22 shows another embodiment of an apparatus according to the invention in a view according to FIG. 3, wherein a sensor which comprises electronics and/or a power-supply source on the filter frame and a measuring head approximately centrally based on the clear width of the filter fleece is on the filter frame of the apparatus.

[0174] Embodiments of the invention are described by way of example in the following description of the figures, also with reference to the drawings. Here, for the sake of clarity, even if different embodiments are involved, identical or comparable parts or elements or regions have been denoted by identical reference signs, sometimes with the addition of lower-case letters.

[0175] Features that are only described, set out or disclosed in relation to one embodiment can also be provided in any other embodiment of the invention within the scope of the invention. Even if they are not shown in the drawings, such amended embodiments are covered by the invention.

[0176] All the features disclosed are essential to the invention per se. The content of the disclosure of the associated priority documents (copy of the previous application) and the cited documents and the prior art Apparatuses described are hereby incorporated into the disclosure of the application in their entirety, also for the purpose of incorporating individual features or a plurality of features of the subjects disclosed therein into one or more claims of the present application. Even if they are not shown in the drawings, such amended embodiments are also covered by the invention.

[0177] An embodiment of a system 100 according to the invention for filtering air flows is shown schematically in FIG. 1:

[0178] This figure schematically shows a building 11 comprising a plurality of rooms 12a, 12b, 12c. The system 100 for filtering air flows comprises a schematically shown inlet 14, which leads to a recirculating unit 15, out of which an outlet 16 leads. The inlet 14 comprises two intakes 13a, 13b shown by way of example. The outlet comprises two exhausts 17a, 17b shown by way of example.

[0179] As shown schematically in FIG. 2, the recirculating unit 15 may for example comprise a fan 19, a heater 20 and a heat exchanger 21. A cooling unit (not shown), which cools the air flow, may also be provided instead of a heater 20.

[0180] As shown in FIG. 1, the intake 13, 13a, 13b may for example be in or on a wall of a room 12a in the building and may e.g. be provided by an air intake grating, to which an air filter 10a, 18a, shown schematically in FIG. 2, is directly attached. The air is guided to the fan 19 in the direction of the arrow in FIG. 2. Another air filter 10b, 18b may optionally be provided directly on the input side of the fan 19. The fan 19 ensures that the air circulates within the pipe system 14, 16.

[0181] Depending on the number of rooms in the building, the number of intakes 13, 13a, 13b and also the number of exhausts 17, 17a, 17b can be selected as desired. The inlets 14 and outlets 16 may have any cross section, for example a square or rectangular cross section, and may be formed so as to be substantially closed except for the intakes and exhausts.

[0182] An embodiment of an air filter 10a, 10b, 18a, 18b is shown in detail in FIGS. 3 and 4:

[0183] According to the present patent application, such an air filter 18a, 18b is also referred to as an apparatus 10 for filtering air flows.

[0184] According to FIGS. 3 and 4, an apparatus 10 according to the invention comprises a filter frame 22, comprising an insertion compartment for a filter fleece 23, and a retaining device 24. According to FIG. 4, the filter frame 22 comprises an e.g.

[0185] cross-like retaining structure 37, which prevents the mat-like filter fleece 23 from falling out of the frame.

[0186] The retaining device 24 also comprises an e.g. substantially cross-like complementary structure 38, which prevents the filter fleece 23 from falling out of the frame in the rearward direction.

[0187] Instead of a cross-like structure 37, 38 as shown in the drawings, both the filter frame and the retaining device 27 may also have any other geometric design.

[0188] It should be noted that a latch element 25 is shown by way of example in FIGS. 3 and 4, which is pivotable about an axis 39. FIG. 4 shows the latch by way of solid lines in an open position in which the filter fleece 23 and the retaining device 24 can be inserted into the frame. After they are inserted, the latch 25 can be pivoted by approximately 90° anticlockwise about the pivot axis 39 out of the open position according to FIG. 4 into the closed position according to FIG. 3, and can secure the retaining element 24 on the filter frame 22.

[0189] The construction described is merely an example of a plurality of configurations of filter frames 22 and retaining devices 24 that are possible and acceptable in the context of the invention.

[0190] According to FIG. 5 to 8, different examples of transport packaging and compressed filter fleeces will now be set out:

[0191] According to FIG. 4 in connection with FIG. 5 to 7, it should first be made clear that a filter fleece 23 for insertion into a filter frame 22 has a height 26, a width 27 and a thickness or wall thickness 28a.

[0192] If a filter fleece 23 of this kind is in transport packaging 30 so as to be compressed, in particular evacuated, according to the invention, according to FIG. 7 a dimension of the thus compressed filter fleece results such that the filter fleece only still has a height 34 that is considerably less than the height 26 of the non-compressed filter fleece, and has a thickness or wall thickness 35 that is considerably less than the thickness 28a of the non-compressed filter fleece. The width B of the compressed filter fleece 33 is considerably reduced compared with the width 27 of the non-compressed filter fleece (FIG. 4).

[0193] According to the embodiment in FIG. 7, the transport packaging 30 can be provided by a transparent, airtight plastics film.

[0194] In this respect, FIG. 7 shows a single fleece comprising a single item of transport packaging 31.

[0195] FIG. 8 shows an embodiment in which a plurality of filter fleeces 33a, 33b, 33c, 33d are each individually compressed and are each surrounded by a single item of transport wrapping 31a, 31b, 31c, 31d. In addition, in the embodiment in FIG. 8, a fastening device 40 is provided which fastens the individual, compressed filter fleeces 33a, 33b, 33c, 33d to one another. This fastening device 40 may for example be formed by another plastics envelope or by adhesive tape or another fastening means.

[0196] The embodiment in FIG. 6 shows a plurality of compressed filter fleeces:

[0197] While FIG. 5 shows a plurality 29 of non-compressed filter fleeces 24a, 24b, 24c, 24d having a total thickness 28b, FIG. 6 shows a plurality of compressed filter fleeces 33a, 33b, 33c, 33d of which the total thickness 36 is considerably reduced by comparison. According to the embodiment in FIG. 6, the individual filter fleeces 33a, 33b, 33c, 33d are together surrounded by transport packaging 30, known as a transport multi-pack 32. This may advantageously also be airtight, and may for example be provided by a transparent plastics film.

[0198] The embodiments in FIGS. 7, 8 and 9 show that the volume requirements of such compressed filter fleeces 33a, 33b, 33c, 33d are considerably reduced compared with non-compressed filter fleeces 24a, 24b, 24c, 24d. As a result, the space required both for transport and storage can be reduced.

[0199] If the filter fleeces are intended to be replaced on site, the transport packaging just has to be opened. The filter fleece can relax from the compressed state into the non-compressed state and can be directly fixed to the filter frame.

[0200] According to the embodiment in FIG. 9, an apparatus for filtering air flows according to claim 6 is denoted by reference sign 10 in its entirety.

[0201] As in the preceding embodiments, an apparatus of this kind comprises a filter frame 22 and a filter fleece 23.

[0202] A retaining device 24 may optionally be provided, which secures the filter fleece 23 to the filter frame 22. A latch (not shown in FIGS. 9 and 10) may optionally also be provided. Of course, other latch elements can also be covered by the invention.

[0203] According to the embodiment in FIGS. 9 and 10, a sensor 41 is on the filter frame 22. The sensor may be designed to receive information from the filter fleece 23 or to receive information regarding the filter fleece, and/or to receive or obtain information regarding the status of the filter fleece, e.g. the level of soiling or the service life.

[0204] In a variant of the invention, the sensor 41 may also be designed to transmit information to a control room or controller 44 of the system 100.

[0205] The special feature of the embodiment in FIGS. 9 and 10 is that the sensor 41 is securely on the filter frame 22 and remains there when a filter fleece 23 is changed and is replaced with a new filter fleece 23. In this respect, the only consumable material is the filter fleece 23. The filter frame 22 and the sensor 41 attached thereto can also be reused after a new filter fleece 23 is reattached. This ensures that an apparatus 10 according to the invention for filtering air flows is provided in a sustainable and beneficial manner.

[0206] According to the embodiment in FIG. 11, an apparatus according to the invention for filtering air flows is intended to be explained, which again comprises a filter frame 22 and a filter fleece 23. In this embodiment too, a retainer 24 is provided, which can detachably fix the in particular replaceable filter fleece 23 to the filter frame 22. A latch (shown in some of the preceding embodiments) may optionally also be provided.

[0207] According to the embodiments in FIGS. 11 and 12, the apparatus 10 comprises a sensor 42. In one embodiment of the invention, the sensor 42 may also be in addition to the above-described sensor 41, may also be connected to a sensor 41 of this kind, or may also form a unit together with a sensor 41 of this kind.

[0208] A memory element 43 may be assigned to the sensor 42, in particular may be connected to the sensor 42, or may be an integral part of the sensor 42.

[0209] The sensor 42 is designed to determine or detect information regarding a property of the filter fleece 23.

[0210] A property of the filter fleece 23 may for example be an identification number of the filter fleece, a serial number, an article number, a product category number, information regarding the material used for the filter fleece, or other information regarding the filter fleece. For example, the information may also include a note as to what types of particles the filter fleece is supposed to be used for, what areas of application are covered, what expiration dates or what manufacturing date the filter fleece 23 has, what the prescribed service life of the filter fleece 23 is, etc.

[0211] The information may for example be directly detected optically, electromagnetically, inductively, capacitively or in another suitable way by the sensor 42. Therefore, for example, as shown in the embodiments in FIGS. 11 and 12, an information carrier 45 may be on the filter fleece 23 itself. For example, the information carrier 45 may be formed by an RFID tag, and the sensor 42 may in turn have an RFID reader. Other technologies for reading out information stored in the information carrier 45 by the sensor 42 are also covered by the invention, such as NFC, Bluetooth, WLAN, etc.

[0212] In the simplest case, the information carrier 45 on the filter fleece 23 is not provided with its own power source, but instead either an externally excitable resonant circuit or an optically readable element, such as a barcode, a number or the like, which can be optically read out by the sensor 42, are provided.

[0213] The information from the information carrier 45 can be input by the sensor 42 when the filter fleece 23, in particular once the filter fleece has been replaced in accordance with a prescribed service life, is brought close enough to the filter frame or has been inserted into the filter frame 22. The sensor 42 (not shown in the drawings) may also have a trigger button or switch which, when actuated, initiates the input process.

[0214] In another embodiment of the invention, information regarding the filter fleece 23 is detected by the sensor 42 not directly with the aid of a direct operative connection between the filter fleece 23 and the sensor 42, but instead with the aid of an operator. For example, a technician who is replacing a filter fleece 23, e.g. with the aid of a handset, e.g. a mobile telephone, in particular with the aid of suitable software, can communicate to the sensor 42 that a new filter fleece 23 has been inserted into the filter frame 22 and optionally also what type of filter it is, etc.

[0215] In any case, the sensor 42 is capable of detecting information regarding the filter fleece 23.

[0216] Advantageously, this information can also be stored in the memory element 43.

[0217] According to the embodiment in FIGS. 13 and 14, it is explained that the sensor 42 and/or another suitable sensor 41 can transmit information from the apparatus 10 to a controller 44 of a system 100 for filtering air flows.

[0218] FIG. 13 indicates a connection line 57 which connects the sensor 41, 42 to the controller 44. The connection line 57 may be a physical connection line, i.e. a cable or wire, or may be a radio link, for example using WLAN, Bluetooth, NFC, GSM or another suitable radio protocol. Optical or acoustic connection links 57 are covered by the invention.

[0219] As indicated in FIG. 18, for example, the controller 44 can control the entire ventilation process and, for example, the heating apparatus, cooling apparatus, humidifiers, fan, and recirculating unit 15. The controller 44 may in particular be designed to manage maintenance information, initiate maintenance processes, or communicate to external companies or persons that certain filters 10a, 10b require maintenance.

[0220] To do this, information can be received by the sensor 41, 42 from the controller 44 using the connection lines 57. The received information may include information regarding a property of the filter or filter fleece and/or information regarding the status of the filter fleece and/or information regarding a position of the filter 10 or filter fleece 23.

[0221] The invention also covers the case in which the connection line 57 is not provided directly between the sensor 41, 42 and the controller 44, in the sense of a direct connection, but instead is provided indirectly, by inserting an additional element. This additional element may for example also be a portable, e.g. handheld, mobile electronic device, e.g. a mobile phone. In this intermediary connection, an item of the above-mentioned information can be read out e.g. from the sensor 41, 42 by the mobile device, and can later be transmitted from the mobile device to the controller 44.

[0222] According to the embodiments in FIGS. 15 and 16, Apparatuses according to the invention will now be described which comprise a sensor 41, 42 for determining a level of soiling or a service life of the filter fleece 23. To do this, the sensor 41, 42 may comprise an apparatus 52 for status detection or may be connected to such an apparatus.

[0223] At this point, it should be noted that such an apparatus 52 for status detection may also be integrated in the sensor 41 and/or the sensor 42. The invention in particular also covers embodiments not shown in the drawings which comprise such a sensor 41 or sensor 42 in which an apparatus for status detection is integrated.

[0224] By way of example, FIGS. 15 and 16 show measurement arrows P1 and P2 which are intended to indicate that the sensor 41, 42 or the apparatus 52 can emit a measured signal (P1) and can receive a measured signal (reflection signal P2 or measured signal P2). The measurement arrows P1 and P2 are intended to indicate that e.g. an optical, electromagnetic, capacitive or inductive measurement or a moisture measurement or a mechanical measurement or another suitable measurement can be carried out in order to establish whether a certain level of soiling or clogging of the filter has been reached. As the filter fleece is operated with an increasing service life, increasing quantities of particles are of course deposited in the filter fleece 23. Depending on the type of particles to be filtered and depending on the type of filter fleeces 23 used, these particles may eventually result in optimized air filtering no longer being guaranteed. The maximum service life of the filter fleece 23 has then been reached, and the filter fleece needs to be replaced.

[0225] The status of the filter fleece 23 can be determined or detected regularly or irregularly, in an automated manner or automatically, or so as to be initiated by an operator.

[0226] FIG. 17 shows an embodiment of an apparatus 10 according to the invention in which position information can be transmitted from a sensor 41, 42 to a controller 44 of a system 100 via an operative connection 57.

[0227] According to the embodiment in FIG. 18, such a system 100 according to the invention is shown, which comprises an inlet 14, an outlet 16, a plurality of air intakes 13a, 13b and a plurality of air exhausts 17a, 17b.

[0228] Apparatuses 10a, 10b for filtering air can be in the region of the air intakes 13a, 13b.

[0229] Another air filter 10 may in particular also be in the region of the recirculating unit 15 upstream of a fan that is there but is not shown in FIG. 18.

[0230] The system 100 may have a controller 44 which can be connected to the recirculating unit 15 via an operative line 58. The controller 44 may for example ensure cooling or heating of the air flow and the humidifying or drying thereof, and may also drive or control a unit within the recirculating unit 15, e.g. also a fan that is there but is not shown in FIG. 18.

[0231] In the embodiment in FIG. 18, the controller 44 receives information from the sensors 41, 42 of the air filter 10a via the connection line 57. This may for example be information regarding properties of the air filter 10a or properties of the filter fleece 23 positioned in the air filter 10a and/or may be information regarding the status of the air filter 10a or the status of the filter fleece of this air filter 10a, and/or may be position data of the air filter 10a or the associated filter fleece 23.

[0232] This information is received by the controller 44. The controller 44 is connected to the apparatus 46 for documentation. Together with the apparatus 46 for documentation, the controller 44 can process and manage the received information regarding the inserted filter fleeces 23 and can take the information into account when controlling filtering processes and carrying out maintenance processes.

[0233] According to the embodiment in FIG. 19, a system 100 is provided which receives and/or manages and/or processes position data. The system 100 comprises a recirculating unit 15, to which an air inlet 14 leads, and out of which an air outlet 16 leads. The system 100 comprises a plurality of air filters 10a, 10b. A controller 44 of the system 100 can manage position data.

[0234] To do this, a sensor 41, 42 or an apparatus 49a, 49b is preferably on each apparatus 10a, 10b for filtering air flows for detecting and/or determining and/or storing and/or transmitting and/or assigning apparatus position data. Position data are data which directly or indirectly provide information regarding a location of the apparatus 10a, 10b or a location of the filter frame 22 or a location of a filter fleece 23. This may for example include absolute location information i.e. for example indicating that a certain apparatus 10a is located in a certain room on a certain floor of a certain building, or relative location information for example indicating that a certain air filter 10a is located in spatial proximity to another air filter 10b.

[0235] As shown by the dashed line 47, which interconnects a sensor 41, 42 and the controller 44 in each case, this position data and position information can be transmitted from the sensor 41, 42 to the controller.

[0236] At the same time or separately, property information 48, i.e. information regarding properties of the air filter 10a, 10b or information regarding the properties of the filter fleeces 23 inserted and used therein, can also be transmitted via this connection line, which in turn can be designed wirelessly or in a wired manner or optically.

[0237] The controller 44 can interlink this information and/or manage this information in an interlinked manner. In this respect, the controller 44 knows where which air filter is located, what type of air filter has been inserted, and when it is necessary to replace a filter. Advantageously, the controller 44 also receives status information regarding the filters and, in this respect, knows what level of soiling or clogging a particular air filter 10a, 10b has at a particular point in time.

[0238] An apparatus 49a, 49b which can determine position data can be in a single apparatus 10a, 10b. To do this, for example known methods for position detection can be used, for example using GSM information and position information.

[0239] The invention also covers the case in which the apparatus 49a, 49b for information detection can store position data. The invention also covers the case in which the apparatus 49a, 49b for position-data detection makes it possible to assign position information to a particular filter frame 22 or to a particular filter fleece 23. For example, assigning position information in this way can also be carried out with the aid of an operator and/or a mobile electronic device.

[0240] According to the embodiment in FIG. 21, an apparatus 10 according to the invention for filtering air flows is explained, which comprises a filter frame 22 and a filter fleece 23 and optionally also a retaining device 24. The special feature of this device is that an apparatus 50 is provided for displaying or retrieving information regarding the status of the filter fleece 23. To do this, a sensor 41, 42 may be provided which, similarly to the above-described embodiments, displays or detects information regarding the status of the filter fleece 23.

[0241] Preferably, regular or irregular measurement can be used to establish whether a certain level of soiling of the filter fleece 23 has been reached.

[0242] The apparatus 50, which comprises a display for the status information, can be connected to the sensor 41, 42. The display apparatus 50 may for example comprise one red and one green LED or a single color-changing LED. As long as the level of soiling of the filter fleece 23 is not so high that it is necessary to replace the filter fleece, the green LED is lit up. When the level of soiling increases above a threshold value, the red LED lights up and indicates to an operator that it is necessary to replace the filter fleece 23.

[0243] Of course, a display apparatus 50 of the type described is only useful in those Apparatuses 10 which are directly visible to an operator. The display apparatus 50 can be provided at a suitable point, in particular on the frame 22 of the filter, which is easily visually accessible.

[0244] The apparatus 10 according to the invention may optionally or additionally also be provided with a request apparatus 51 for requesting status information. This request apparatus 51 may likewise be connected to the sensor 41, 42, and this is not shown in FIG. 21. The status information may for example be retrieved with the aid of a handset 60 shown schematically in FIG. 21. Therefore, when the handset 60 is brought close enough to the request apparatus 51, an operator can read out the status information wirelessly or optionally also in a wired manner.

[0245] In an alternative configuration of the invention, the display apparatus 50 is designed such that the status information is permanently displayed, and therefore the LED is always lit up in green or red. In an alternative configuration of the invention, an actuating element (not shown in FIG. 21), e.g. a switch, is provided which prompts the display apparatus 51 to produce a display as a result of being actuated.

[0246] According to the embodiment in FIG. 22, another aspect according to the invention is illustrated:

[0247] FIG. 22 shows an embodiment of an apparatus 10 according to the invention in which an apparatus 41, 42 is for determining information regarding the status of a filter fleece. To do this, the apparatus 41, 42 in particular comprises a power source 53, e.g. a battery, which is only indicated schematically, and respectively indicated electronic components 54. According to the embodiment in FIG. 2, these components are directly on the frame 22 and do not project inwards beyond the inner contour 56 of the frame. The apparatus 52 for status detection further comprises a measuring head 55, however, which takes a measurement in order to obtain status information. This measuring head 55 is compact and projects inwards beyond the inner circumferential contour 56 of the filter frame and is in particular within this inner circumferential contour 56. In the embodiment in FIG. 22, the measuring head 55 is centrally within the clear width of the filter fleece 23.

[0248] Advantageously, the measuring head 55 may be on a retaining device 24, which fixes a filter fleece relative to the filter frame 22.

[0249] Because only the measuring head 55 is within the clear width of the filter fleece 23 in the apparatus 52, on one hand, the measurement can be taken at an advantageous location, and on the other hand, the air flow through the filter is not impaired or is only very slightly impaired.