FILTER ARRANGEMENT WITH CODING ELEMENT

Description

[0001] The invention relates to a filter assembly comprising a filter element and a filter housing for accommodating the filter element. The filter element is formed with a filter frame, a bellows made of filter medium accommodated in the filter frame, and a seal extending around the outside of the filter frame. State of the art

[0002] DE 10 2005 048 841 A1 discloses a filter element that is inserted into a housing of a motor vehicle's ventilation system. Specifically, in this filter arrangement, guide pins on the housing correspond to guide slots in the filter element. This is intended to create a mechanical coding system that ensures that only a filter element suitable for that housing is inserted into the housing. A disadvantage is that the filter surface is compromised by the guide pins, and the filtration performance can be reduced.

[0003] DE 10 2009 059 782 84 B4 shows a filter element for insertion into a housing of a ventilation or air conditioning system, comprising a bellows and at least one coding side that can be turned toward a wall of the housing, with a profile associated with the coding side. The filter element can be inserted into the housing with its narrow side, with the profile facing forward, and is therefore also referred to as a "front loader." The described coding does not work for a so-called "top loader," in which the filter element is inserted in the flow direction.

[0004] DE 10 2014 009 887 A1 shows a filter with a filter element and a filter housing. The circumferential seal on the filter element is provided with two bulges. These two bulges engage with raised portions on the filter housing during assembly, enabling the filter element to be positioned correctly within the filter housing. Task

[0005] The invention is based on the object of specifying a mechanical coding for a filter element which ensures a clear assignment of a filter element to a filter housing and does not impair the effective filter surface. Technical solution

[0006] This task is solved by a filter arrangement as described and claimed below.

[0007] According to the invention, it was recognized as advantageous to integrate coding elements into the seal of the filter element or into the filter housing.

[0008] The invention relates to a filter arrangement comprising a filter element as described below and a filter housing for releasably receiving and holding the filter element. According to the invention, at least one housing-side mechanical coding element is integrated into the filter housing. The mechanical coding element has a specific geometry and is spatially and physically designed. The filter-side coding element and the housing-side coding element are shaped complementarily to one another and thus together form a coding device. If multiple housing-side coding elements are provided, the same number of filter-side coding elements can be provided.

[0009] The filter element is used for air filtration in a vehicle cabin and comprises a filter frame, a bellows made of a filter medium, e.g., nonwoven fabric, housed in the filter frame, and a seal running around the outside of the filter frame to seal it against a filter housing in which the filter element can be housed. In one possible embodiment, the filter frame can be formed by so-called edge bands.

[0010] At least one filter-side mechanical coding element is integrated into the seal. The mechanical coding element has a specific geometry and is spatially and physically designed. The mechanical coding is therefore not a chemical, magnetic, or electronic coding. The filter-side coding element can interact with a housing-side coding element as a counter-element, forming a coding device together with it. If multiple filter-side coding elements are provided, the same number of housing-side coding elements can be provided.

[0011] The function of the coding element and the coding device is to provide coding to protect against counterfeiting. Only filter elements with an original coding element can be inserted into the filter housing. Furthermore, the coding element can also serve as a positioning aid, ensuring the correct insertion of the filter element into the filter housing—that is, ensuring that the filter element is correctly positioned within the filter housing during assembly.

[0012] The inventive arrangement of the filter-side coding element integrated into the seal advantageously ensures that there is no impairment or reduction of the effective filter surface of the bellows.

[0013] According to the invention, the filter-side coding element is designed as a recess in the seal, particularly as a groove, notch, or channel. Such a recess is easy to manufacture and can hardly be subsequently created on the seal by a product pirate without damaging the seal and thus risking leakage.

[0014] According to the invention, the seal in the area of ​​the filter-side coding element has a reduced height compared to the height of the seal in areas where no coding element is located. The reduced height can be, in particular, 20-80% of the regular height. The height of the seal refers to the thickness of the seal viewed in the insertion direction.

[0015] The filter element seal is designed as a radial seal for radial sealing of the filter element against a receiving filter housing. A radial seal can ensure a good and tight fit of the filter element in the filter housing. The filter housing of the filter assembly has a step on its inside as a circumferential shoulder, which forms a contact surface for the seal, namely an axial contact surface. This enables particularly secure installation of the filter element in the filter housing.

[0016] The radial seal may, in particular, have a compensation groove. For this purpose, the compensation groove may be incorporated into the raw gas-side surface of the radial seal.

[0017] It has been recognized as advantageous if the filter element seal is made of an elastomer, particularly a polyurethane (PU) made of flexible foam, a thermoplastic elastomer (TPE), or an ethylene propylene diene rubber (EPDM). Elastomers with Shore hardnesses of 15-50 Shore A are preferred.

[0018] The seal can be manufactured in a separate production process and connected to the filter frame with a form-fitting connection. For the form-fitting connection, a circumferential groove, in particular a circumferential groove, can be provided in the seal, which engages with a circumferential tongue on the filter frame. The tongue can, if necessary, be formed by the edge band. This allows the seal to be slipped over the filter frame during assembly of the filter element, thus enabling the seal to be reused for a new unit consisting of the filter frame and bellows, which is environmentally advantageous.

[0019] Alternatively, the seal can be produced in a single manufacturing step and bonded to the filter frame. For this purpose, the seal can be foamed or cast onto the filter frame, which is advantageous from a manufacturing perspective.

[0020] The bellows could have multiple layers, including one with activated carbon. This allows the filter element to be used as a combination filter, which can adsorb not only dust particles but also unpleasant odors or gases.

[0021] A filter element of the type described here could be installed in a housing of an air conditioning system.

[0022] In a particularly advantageous and therefore preferred development of the filter assembly according to the invention, the housing-side coding element is designed as a raised portion, in particular as a spring, lug, or rib, which is raised above the inner surface of the filter housing. The inner surface of the filter housing faces the outer circumferential seal of the filter element when the latter is mounted in the filter housing.

[0023] Such a raised portion is easy to manufacture. If the filter-side coding element is designed as a recess, the raised portion on the housing can be accommodated in the recess in the seal.

[0024] In a possible design of the filter arrangement, the raised portion extends over only part of the height of the filter housing. This ensures a particularly good seal between the gasket and the filter housing. The height of the filter housing refers to the extension of the filter housing in the insertion direction.

[0025] In a particularly advantageous and clever filter arrangement from a manufacturing point of view, the elevation is made of one piece and the same material as the filter housing and is manufactured from plastic, for example, in an injection-molding process.

[0026] In an advantageous embodiment of the filter assembly, the bellows is located in a filter plane, and the insertion direction when installing the filter element into the filter housing is oriented perpendicular to the filter plane. Such a filter assembly is also referred to as a top-loader (as opposed to so-called front-loaders). In such a filter assembly, it has been recognized as advantageous if the coding elements extend in the insertion direction and thus perpendicular to the filter plane. In one possible embodiment, a raised portion and a recess can serve as coding elements extending in the insertion direction and interlocking during assembly.

[0027] The invention also relates to the use of a filter assembly as described above as an interior air filter for filtering and purifying the cabin air in a vehicle subject to increased pollutant loads, in particular in a commercial vehicle, a heavy-duty vehicle, or an off-road vehicle. These vehicles can be, for example, trucks, construction machinery, agricultural machinery, or forestry vehicles.

[0028] The filter element can be used in the cabin of a vehicle to filter either secondary air or fresh air. Secondary air refers to air that is first extracted from the cabin and then filtered and returned.

[0029] The described invention and the described advantageous developments of the invention also represent advantageous developments of the invention in combination with one another - insofar as this is technically reasonable.

[0030] With regard to further advantages and advantageous embodiments of the invention in terms of construction and functionality, reference is made to the dependent claims and the description of embodiments with reference to the accompanying figures. Example

[0031] The invention will be explained in more detail with reference to the accompanying figures. Corresponding elements and components are provided with the same reference numerals in the figures. For the sake of clarity, the figures have not been drawn to scale.

[0032] They show in schematic representation Fig. 1a filter element in a perspective view Fig. 2a filter housing for the filter element made of Fig. 1 in a perspective view Fig. 3 a filter arrangement with the filter element from Fig. 1 and the filter housing Fig. 2 in a perspective view

[0033] Fig. 1 shows a perspective view of a filter element 10. The filter element 10 has a filter frame 11 and a bellows 12 made of pleated filter medium 13, which is accommodated in the filter frame 11. The bellows 12 lies in a filter plane E. A seal 14, designed as a radial seal, is attached around the outside of the filter frame 11.

[0034] Three filter-side mechanical coding elements 1 are integrated into the seal 14, which are designed as a recess, each in the form of a notch.

[0035] The seal 14 has a regular height, as indicated by the double arrow 15. However, in the area of ​​the three filter-side coding elements 1, it has a reduced height.

[0036] Fig. 2 shows a filter housing 20 for the filter element 10 from Fig. 1 in a perspective view.

[0037] Three housing-side mechanical coding elements 2 are integrated into the filter housing 20. The housing-side coding elements 2 are each designed as raised portions, namely as lugs. The filter-side coding elements 1 and the housing-side coding elements 2 are thus complementary to one another, can engage with one another during assembly, and together form a coding device.

[0038] The lugs 2 are one-piece and made of the same material as the filter housing 20 and are manufactured from plastic, for example, using an injection molding process.

[0039] The lugs 2 extend only over a part of the height 21 of the filter housing 20, which is indicated by a double arrow.

[0040] On its inner side, the filter housing 20 has a step as a circumferential shoulder 22. This step forms an axial support surface for the seal 14.

[0041] If the filter element 10 is made of Fig. 1rotated by 180° in the filter plane E - as indicated by the round arrow, it can be inserted in the insertion direction e - also indicated by an arrow - into the filter housing 20 from Fig. 2 inserted and mounted in this way. The lugs 2 engage in the notches 1, and the seal 14 rests on the step 22. This ensures that the filter element 10 sits in a clearly defined position in the filter housing 20. Other filter elements 10 without the filter-side coding elements 1, however, cannot be securely mounted in the filter housing 20.

[0042] Fig. 3 shows a filter arrangement 100 with the filter element 10 mounted in the filter housing 20. The filter arrangement 100 can now be flowed through in the flow direction L by an air flow to be cleaned. List of reference symbols

[0043] 1filter-side coding element (recess) 2housing-side coding element (elevation) 10Filter element 11Filter frame 12Bellows 13Filter medium 14Seal 15Seal height 20Filter housing 21Height of the filter housing 22Heel 100Filter arrangement eInsertion direction EFilter level LDirection of air flow

Claims

1. Filter arrangement (100) having a filter element (10) and having a filter housing (20) for accommodating the filter element (10), comprising the filter element (10) with a filter frame (11), with a corrugated bellows (12) composed of filter medium (13) which is accommodated in the filter frame (11), and with a seal (14) which runs around the outside of the filter frame (11), wherein at least one filter-side mechanical coding element (1) is integrated in the seal (14), and the filter-side coding element (1) is in the form of a depression in the seal, in particular in the form of a groove, notch or channel, wherein the seal (14) has a reduced height (15) in the region of the filter-side coding element (1), wherein at least one housing-side mechanical coding element (2) is integrated in the filter housing (20), and the filter-side coding element (1) and the housing-side coding element (2) together form a coding device, characterized in that the seal (14) is in the form of a radial seal, and the filter housing (20) has on its inner side a step in the form of a peripheral shoulder (22), which forms an axial bearing surface for the seal (14).

2. Filter arrangement according to Claim 1, characterized in that the radial seal (14) has a compensation groove.

3. Filter arrangement according to one of the preceding claims, characterized in that the seal (14) is connected in a form-fitting manner to the filter frame (11), wherein, for the form-fitting connection, provision may be made of a groove in the seal (14) and a tongue on the filter frame (11), which engage one inside the other.

4. Filter arrangement according to one of the preceding claims, characterized in that the seal (14) is foamed or cast onto the filter frame (11), and a cohesively bonded connection of seal (14) and filter frame (11) is thus realized.

5. Filter arrangement according to one of the preceding claims, characterized in that the housing-side coding element (2) is in the form of an elevation, in particular in the form of a tongue, nose or rib.

6. Filter arrangement according to Claim 5, characterized in that the elevation (2) extends only over a part of the height (21) of the filter housing (20).

7. Filter arrangement according to Claim 5 or 6, characterized in that the elevation (2) is in one piece with and of the same material as the filter housing (20).

8. Filter arrangement according to one of the preceding claims, characterized in that the corrugated bellows (12) lies in a filter plane (E), the push-in direction (e) for pushing the filter element (10) into the filter housing (20) is oriented perpendicularly to the filter plane (E), and the coding elements (1, 2) extend in the push-in direction (e).

9. Use of a filter arrangement (100) according to one of the preceding claims in the vehicle cabin of a vehicle for filtration of secondary air or fresh air.