Air filter for the indoor air of cabins of vehicles, agricultural, construction and working machines

Technical field

p0001The invention relates to a cabin air filter for a cab air supplied in vehicles, agricultural machinery, construction equipment and machines.

State of the art

p0002From the <patcit id="pcit0001" dnum="WO0033940A1"><text>WO 00/33940 A1</text></patcit> an air filter is known which an outer layer of activated carbon combined with a layer of a HEPA filter.

p0003However, the filtering effect of this filter can be used for applications in which, for example, high concentrations of pesticides or (liquid) -Düngemittel concentrations in the ambient air occur, especially when dealing with sprayers for these substances may not be sufficient. This can be particularly disadvantageous when applying liquid pesticides and / or fungicides with agricultural or forestry tractors and self-propelled sprayers for driver or operator.

p0004When aerosol is meant for the following designs a mixture of liquid suspended and air.

p0005It is therefore an object of this invention to provide an indoor air filter with respect to the occurring during the operation of agricultural machinery dusts, aerosols and vapors, in particular of pesticides and fungicides, has better filtering effect.

Disclosure of the Invention

p0006This object is achieved by an interior air filter element comprising a Adsorptionsfilterlage comprising activated carbon, in particular for the separation of gases, a fine filter layer, in particular for the separation of aerosols, and a circumferential seal for separating the raw side from the clean side when installed in a filter housing.

p0007The filter element of the invention can be used in particular for the cab of land and vehicles, in particular with injection or spraying for plant protection or fertilizers. By combining Adsorptionsfilterlage and fine filter layer greatly improved the air quality in the interior of the cab can be achieved reliably even in those, high-stress environments. In the Adsorptionsfilterlage gases are bound particularly harmful and / or unpleasant odor in the upstream or downstream of Adsorptionsfilterlage arranged fine filter layer fine dusts, vapors and aerosols are removed from the breathing air. The fine filter layer is preferably disposed upstream of Adsorptionsfilterlage.

p0008In one embodiment, an upstream side prefilter layer, in particular for separation of dust is additionally provided. This is the Adsorptionsfilterlage and the fine filter layer upstream of and disposed on the upstream side of the indoor filter element. This ensures reliable operation of Adsorptionsfilterlage and the fine filter layer can be secured even in very dusty environments, the dust load of the intake air can be reduced.

p0009The activated carbon used, for example, obtained from wood or coal, polymer-based, teerbasiert, or coconut shell-based. In a preferred embodiment lonenaustauscherkügelchen as raw material for the activated carbon are used, which are made of polymer-based, for example, synthetic resins, in particular with divinylbenzene cross-linked polystyrene.

p0010In one embodiment, is used as the activated carbon, a hydrophobic active carbon. Hydrophobic active carbons in particular are meant those which have a relatively low water absorption capacity. Preferably an activated carbon is used, which at a relative humidity of 50% a water absorption of &lt;10 percent by mass, in particular with respect to having the adsorption branch of the isotherm. Particularly preferably, this water absorption &lt;5 percent by mass.

p0011In one embodiment, the activated carbon has a BET surface area of ​​greater than 400 m²/ G, preferably greater than 600 m²/ G, preferably greater than 800 m²/ G, particularly preferably greater than 1000 m²/ G (preferably measured in accordance with DIN ISO 9277: 2003-05). This can be ensured in a small space sufficient adsorption.

p0012In one embodiment, activated carbon is used in pourable or free-flowing form, for example in the form of grain or spheroidal or otherwise shaped particles. The activated carbon particles preferably have activated carbon particle sizes (average diameter) between 0.1 and 1 mm, preferably 0.2 to 0.7 mm and may be present for example in the form of granular activated carbon or spherical activated carbon.

p0013In one embodiment, can be used as the prefilter an unfolded or zigzag-shaped folded filter medium. This may for example consist of cellulose, plastic foam or fleece or comprise a single- or multilayer combination of layers of such filter media.

p0014A plastic foam filter media layer for the prefilter, for example, from a reticulated foam, in particular polyurethane foam, made, for example on polyether or polyester-based or include one or more layers of this foam. Bulk densities of such foams may range from 20 - 70 kg per m³ be.

p0015As cellulose filter medium for the prefilter may occur with Epoxidimprägnierung used for example a cellulose filter medium. Preferably, the cellulosic filter media has a basis weight of 80-140 g / m², Preferably 100-120 g / m² on. In a preferred embodiment, the medium has a maximum pore size in the range 30-40 microns and / or an air permeability of 100 - 400 l / m²s, preferably between 200 and 300 l / m²s measured in each case (measured here and hereinafter preferably according to DIN EN ISO 9237) at a pressure difference of 200 Pa. In this way, the subsequent layers can be protected from dust deposition, and thus the function of which will be secured. In one embodiment is the Imprägniergehalt, ie the proportion by weight of the impregnating agent at the basis weight of the filter medium is between 15 and 30%.

p0016As nonwoven filter medium for the prefilter can be used (of meltblown nonwoven synthetic fibers) preferably a combination of a spunbond layer and a meltblown layer. Both layers can each consist of polyamide (PA), polyester (PES) or polypropylene (PP) may be produced. The non-woven filter media preferably has a basis weight between 60 and 140 g / m², Preferably between 80 and 120 g / m² and / or a thickness in the range 0.5 to 1 mm, particularly preferably 0.5-0.8 mm. More preferably, the air permeability in the range 1000 is - 2000 l / m²s, more preferably 1200 to 1800 l / m²s at a pressure difference of 200 Pa.

p0017In one embodiment, the prefilter in particular ISO 5011 an efficiency of 99% for test dust PTI fine particular ISO 14269-4 on.

p0018The prefilter layer, in a preferred embodiment a basis weight 75-125 g / m² on. Preferably, the filter medium of the pre-filter layer has an air permeability from 100 to 200 l / m²s at a pressure difference of 200 Pa.

p0019By using the pre-filter layer can be achieved that the adsorption layer and the fine filter layer to be protected from excessive dust load. Thereby the function (degassing of the adsorption layer and aerosol deposition of the fine filter layer) will be affected even at very dust-laden air intake to a minimal extent.

p0020For Adsorptionsfilterlage an open-cell foam can be used for example with flowing activated carbon. In this example, reticulated foams z. B. from plastics such as polyurethane, polyurethane ether or polyurethane ester are used. Preferably, the pore sizes of the foam amount to between 20 and 50 ppi (pores per inch) or between 0.5 and 2 per millimeter pore. is measured in a comparative optical method in which defined under the microscope a fully formed pore as "Standardpore" and the pores occurring there be compared with this and counted over a stretch. Pores are not fully formed in comparison to Standardpore be proportionately counted. In this foam activated carbon particles are preferably introduced and preferably fixed. The activated carbon particles are preferably fixed by means of an adhesive, for example by means of a two-component adhesive based on polyurethane, in the foam. This can for example be achieved in that the foam is first impregnated with an adhesive, and then before the glue dries or hardens activated carbon particles in particular with shaking are trickling. In this case can be used a two-component adhesive, a hot melt adhesive or an aqueous adhesive.

p0021In one embodiment, as Adsorptionsfilterlage a position of a fixed bed of activated carbon used. This can be realized in a single-ply or multi-ply construction. When fixed bed arrangement is referred to in which a backing layer is provided and is fixed on this a bulk layer of activated carbon particles. As a carrier layer, for example a plastic stretch mesh or a layer of a sheet material, may be used, for example, a particulate filter medium. In a preferred embodiment, the support layer is a nonwoven of spunbond or melt blown polyester fibers, for example, PET fibers (polyethylene terephthalate) or PBT fibers (polybutylene terephthalate) is used. This can be a basis weight of 25-120 g / m², Preferably 50-100 g / m², More preferably 65-85 g / m² and an air permeability> 3000 l / m²s, preferably> 5000 l / m²s at a pressure difference of 200 Pa. the air permeability is measured in particular according to ISO 9347th The bulk layer of activated carbon particles is applied to the carrier layer and preferably fixed by means of a fine adhesive coating on the backing layer. This occurs for example in the form of a variety of on the carrier layer applied adhesive points or by means of a network of adhesive filaments which is applied between the carrier layer and bulk layer and / or between the bulk layer during the filling and / or the fill layer. The bulk layer preferably comprises a circulation of 100-1200 g / m² Activated carbon particles on the carrier layer. Preferred builders between 800 and 1000 g / m² for use. The location of a fixed bed with support layer and bulk layer preferably has an air permeability in the range of 800 - 1200 l / m²s, in particular between 900 and 1100 l / m²s and a basis weight in the range of 850 to 1250 g / m²Especially 950-1150 g / m² at a layer thickness in particular in the range of 2 to 6 mm.

p0022In this way, a stable, easy to process and powerful position of a fixed bed is provided, which can be summarized by machine into multilayer semifinished products.

p0023In one embodiment, an unfolded or folded zigzag layer structure comprising a support layer, a cover layer and in between of introduced, flowable activated carbon is used for the Adsorptionsfilterlage. Thus, a semi-finished product, each having a support and cover layer and an interposed bulk layer is formed. Such composite products can, in turn, to increase the filtration capacity be multiply arranged one above the other, for example between two and 20, semi-finished products, preferably 5-15 semifinished products.

p0024The cover layer can be arranged directly on the fill layer, and, for example, comprise a plastic mesh or a layer of sheet material, for example, a particulate filter medium or consist of. In a preferred embodiment, is used as covering layer a non-woven made of spunbond or melt blown polyester fibers. This can be a basis weight of 25-120 g / m², Preferably 50-100 g / m², More preferably 65-85 g / m² and an air permeability> 3000 l / m²s, preferably> 5000 l / m²s exhibit.

p0025In one embodiment, the Adsorptionsfilterlage a layer structure of a plurality of fixed beds. For example, a first layer of a fixed bed with the side on which the activated carbon is arranged (activated carbon side), set fixed on the activated carbon side a second layer bed and are connected to this for example by gluing. Thus, a semi-finished product with two carriers or layers and arranged in between bulk layer is formed. Such semi-finished products can turn to increase the filtration capacity are multiply arranged one above the other, for example, between two and 10 semi-finished products, preferably between 3 and 7 Semi-finished products. Alternatively or in combination, arrangements are also conceivable, in each of which the carrier layer a layer of a fixed bed is placed on the activated carbon layer to another fixed bed. This arrangement can then be completed by the reversed position with a fixed bed or a topcoat. For example, can be arranged in succession 4 to 20 layers of a fixed bed.

p0026In one embodiment, the entire Adsorptionsfilterlage form a zig-zag folded layer structure or comprise individual, superimposed, separately folded or unfolded layers of semi-finished or layers of fixed bed.

p0027several Adsorptionsfilterlagen can preferably by means of the variants shown in layer structure comprising a support layer, a topcoat and intermediate introduced, flowable activated carbon superimposed a Gesamtadsorptionsfilterlage form. There are, in particular, 2 to 30, preferably arranged in succession 5-15 layers of semi-finished products or by fixed bed to form the Gesamtadsorptionsfilterlage and optionally by means of a connecting means, sealingly connected, for example, of a side strip of fleece or textile together to form a Adsorptionsteilfilter. In this case the sideband may be connected by an adhesive with the layers. Alternatively, for a particular sideband can be glued, molded or welded plastic frame or one integrally cast to the layers by means of a mold casting compound, in particular polyurethane, are used for the lateral sealing.

p0028In one embodiment, the Adsorptionsfilterlage on two regions of different density activated carbon. Here, a region of higher carbon density on the downstream side and an area with lower carbon density on the upstream side is preferably arranged. This can for example be achieved in that two layers of different filled with activated carbon particles foams are placed on each other, wherein the downstream layer a higher degree of filling of activated carbon than the inflow-side location. Alternatively, as described above in different variants described a layered structure of layers with fixed beds are used by activated carbon particles, wherein one or more downstream layers or plies, conclude particular the layer structure towards the outflow side have a higher carbon density. This can for example be achieved in that, for the same materials for carrier layers, bulk layers and cover layers, the downstream layers in particular before, during or calendered after the hardening of the adhesive in such a manner will be that the layer thickness is reduced, and thus the activated carbon density is increased. However, it may also for the layer (s) a granular activated carbon may be used with higher density activated carbon, which has a higher bulk density than the materials for the lower density used. This can either be achieved by activated carbons with different specific gravity or by different geometries of the particles. Thus, a barrier layer is particularly shown, which can reliably enable the deposition of residual concentrations of harmful gases. This allows an additional safety for the user are provided.

p0029In a preferred embodiment the Adsorptionsfilterlage has a downstream zone comprising one or more particular calendered sheets of fixed bed. This layer (s) preferably have a circulation of activated carbon from 100-1200 g / m² Activated carbon particles on the carrier layer. Preferred builders between 800 and 1000 g / m² for use. The location of a fixed bed with support layer and bulk layer has this preferably has an air permeability in the range of 800 - 1200 l / m²s, in particular between 900 and 1100 l / m²s and a basis weight in the range of 850 to 1250 g / m²Especially 950-1150 g / m² at a layer thickness in particular in the range of 1 to 3 mm. More preferably, these layers or this location point in the downstream region of higher carbon density is substantially the same circulation of activated carbon particles with respect to the basis weight and / or the type of activated carbon particles as the preceding, upstream layers with lower activated carbon density. More preferably, this layer or these layers a significantly lower layer thickness than the preceding, upstream layers with lower carbon density. The layer thickness, for example, shorter than 2/3 of the thickness of the foregoing, the upstream layers with lower carbon density, preferably between 40% and 60% of the thickness of the foregoing, the upstream layers. For this example, the layer or layers with a higher carbon density by a calendering or similar methods are so compacted that compared to the unprocessed layer such thickness reduction is achieved. In this way, the various regions of different density activated carbon can be produced from the same raw materials, with only an additional calendering step is necessary to produce the documents with higher carbon density.

p0030In a preferred embodiment a bed of activated carbon particles is used for the layer or layers with higher density activated carbon, which has a higher bulk density in comparison with the preceding, upstream layers with lower density activated carbon. Preferred is the bulk density in comparison with the upstream layers with lower activated carbon density by 50%, particularly preferably 100% higher.

p0031In a particularly preferred embodiment, a bed of activated carbon particles is used for the layer or layers with a higher carbon density used, compared to the preceding, upstream layers with lower activated carbon density of a smaller average particle diameter, in particular a lower by at least 50% average particle diameter, preferably a at least 65% smaller average particle diameter have.

p0032In one embodiment, the upstream layers of lower density activated carbon to activated carbon particles having a particle diameter in the range of 0.7 to 1.2 mm.

p0033In one embodiment, the layer or layers have higher density activated carbon in a packed bed of activated carbon particles having particle diameters in the range of 0.3 to 0.7 mm.

p0034With the described embodiments of Adsorptionsfilterstufe particular a uniform distribution of the activated carbon is achieved, which is also guaranteed during operation, for example, under vibration. In this way, to contribute to the provision of reliable filter element.

p0035With an inventive filter medium for a Adsorptionsfilterlage particular can be provided with a Adsorptionsfilterlage a cabin filter element, which is particularly easy to process. In particular, a cabin air filter element may be provided, the outflow side a test gas concentration below 10 ug / g after the cyclohexane method according to EN 12941: For 2009: 1998 for a test period of 70 min measured according to EN 15695-2.

p0036In one embodiment is used in a glass fiber layer as a fine filter layer an unfolded or zigzag-shaped folded filter medium with glass fibers. This can be used for example a glass fiber fleece or glass fiber paper. This preferably comprises one or both sides a clad layer of a spunbonded web. This mechanical protection of the often very sensitive fiber medium is achieved in particular. This is particularly advantageous if the glass fiber layer is folded, as this in particular the medium can be protected from damage during folding, which could lead to local leaks or cracks. Furthermore, such layers to improve the mechanical strength of the fine filter layer can be used.

p0037In an embodiment of the fine filter layer, the glass fibers have a fiber diameter in the range of 800 nm to 5 microns. Preferably, 90% of the fibers have a fiber diameter within this range. Preferably, fibers with fiber diameters before substantially throughout the fiber diameter range. Preferably, the mean fiber diameter is within said range. The fiber diameter can, for example, according to the in<patcit id="pcit0002" dnum="DE102009043273A1"><text>DE 10 2009 043 273 A1</text></patcit> or <patcit id="pcit0003" dnum="US20110235867A1"><text>US 2011/0235867 A1</text></patcit> Described methods be measured. Preferably, the filter medium of the fine filter layer has a basis weight between 60 and 100 g / m² , particularly preferably between 75 and 90 g / m², The glass fiber layer preferably has a thickness from 0.2 to 1 mm, particularly preferably 0.3 to 0.6 mm. Particularly preferred is a glass fiber layer is used, which s a resistance in the range of 300 at a face velocity of 7.5 cm / - generates 600 Pa, preferably between 400 and 500 Pa. The air permeability (Permeabiliät) is preferably in the range of 25 to 45 l / m²s at a pressure drop of 200 Pa. The pressure loss is at a flow rate of 5.3 cm / s preferably in the range of 200-700 Pa, more preferably between 450 and 600 Pa, or alternatively between 270-480 Pa. The pore size may preferably be in the range 5 to 12 microns, more preferably between 8 and 10 microns.

p0038In one embodiment, the spunbonded fabrics of the outer layer (s), particularly of a polyester or polypropylene or polyamide are formed as material.

p0039In one embodiment, the spunbonded fabrics of the outer layer (s) have basis weights in the range of 10 and 250 g / m², Preferably 20 to 60 g / m² and particularly preferably 30-34 g / m²on. Preferred layer thicknesses for the outer layers are in the range of 0.1 to 0.3 mm.

p0040In one embodiment, the outer layers Spinnvliesder of continuous fibers is formed, which are stretched by means of tempered air and / or galettes and stored confused on a conveyor belt. May optionally follow a calendering operation carried out to produce a fiber composite and / or influencing of the fleece surfaces.

p0041Instead of glass fibers, plastic fibers can be used for the fine filter layer. In one embodiment, such a synthetic HEPA medium is used in place of the glass fiber media described. The material can, for example, polyester or polypropylene or polyamide are used, the fiber layers are preferably formed in web form and, for example, in the electrospinning process, produced meltblown or otherwise. Preferably, an electret is used. Owing to the physical properties of synthetic filter media can be advantageously dispensed with cover and protective layers. Preferably, a layer of meltblown nonwoven polyester with a basis weight of, for example, 80g - 160g / m², Preferably between 80 and 120 g / m² and a thickness of, for example, about 0.4 to 1 mm. This is more preferably applied to a carrier layer. As support layer is for example, a plastic support grid or a spunbond layer into consideration. The other properties can where the fine filter layers described correspond with glass fibers.

p0042In one embodiment, the prefilter and the fine filter layer are integrated into a filter bellows with particular directly superposed layers of a Vorfiltermediums and a fine filter medium.

p0043In one embodiment, a cover layer is laminated on one side of the fiberglass layer, on the other side is directly the prefilter laminated. This layer combination may be either flat integrated into the cabin air filter element or folded as a whole situation combined zigzag, forming a bellows. In this way, a cabin air filter element having a plurality of filter stages can be provided with little installation effort and in a small space.

p0044Layers and / or prefilter may be applied in different ways to the fiberglass layer. Here are for example sprayed adhesives, for example, in aqueous suspension, for example based on PU are used. Alternatively sprayed in powder application processes or applied hot melt adhesives, for example in the form of adhesive fleeces or grids between the layers are used which melt calendering in a fixing and then harden and thus establish a permanent connection. Thus can be produced in particular a secure connection between the fiberglass layer and cover layers which allows folding of the filter medium.

p0045With an inventive filter medium of a fine filter layer can in particular be provided with a fine filter layer, a cabin air filter element, which is particularly easy to process into a bellows. In particular, a cabin filter element can be provided that an aerosol penetration of ≤ 0.05% measured according to EN 15695-2: reaches of 2009.

p0046In the filter element according to the invention prefilter and / or the Adsorptionsfilterlage and / or the fine filter layer may each form a separate part of the filter element, or completely or partially connected to each other sequentially in layers.

p0047In a preferred embodiment, the interior filter element comprises successively at least two of the three filter elements prefilter, Adsorptionsfilterlage and fine filter layer. These preferably have in each case a circulating on the narrow sides sideband, which is sealingly connected to the respective sub-filter layer. The sideband may be a textile or nonwoven formed of sideband.

p0048the sides of the filter layer are as narrow sides preferably designates that are not passed through. The narrow sides surround the inflow and outflow sides or surfaces. In a media structure, which is formed by zigzag folding of a medium, the term narrow sides thus includes both the surfaces formed by the zig-zag shaped course of two edges of the medium (end faces) and parallel to the fold edges extending end surfaces.

p0049In one embodiment, the prefilter and / or the Adsorptionsfilterlage and / or the fine filter layer are superimposed directly and are folded as a unit zigzag.

p0050In one embodiment, the portion of filter elements to form the interior filter element are in particular directly one another and are connected by means of a frame with one another in a sealing, in particular by means of a peripheral to the common narrow edge side strip, in particular of non-woven or textile, which is welded with the part filter elements or may be glued together.

p0051Alternatively it can be provided a particular injection-molded plastic frame. This can be either prefabricated and absorb part filter elements which are glued or welded to the frame. Alternatively, the frame may be formed as overmoulded frame formed thereby are that the partial filter elements inserted into a mold and then molded with an injection molding frame, the material bonds upon curing undetachably with the part filter elements.

p0052Further alternatively, the frame by a casting compound made of polyurethane (PUR) or other moldable polymer can be formed, in particular of a foamed polyurethane, ie, polyurethane foam.

p0053In one embodiment, the seal is formed by a circumferential sealing profile made from a polymer, especially from a partially foamed, in particular closed-pore foam, for example polyurethane foam. Is also the frame of such a material is formed, the gasket can be integrally formed with the frame. Preferably, the seal has a hardness in the range between 5 and 45 Shore A, more preferably from 13 +/- 4 Shore A.

p0054In a preferred embodiment the gasket between two housing parts of a filter housing is axially or radially compressible sealing or clamped.

p0055The invention further relates to a cabin air filter system for the cab of land and vehicles, in particular with injection or spraying of pesticides or fertilizers, comprising an inventive interior air filter element and a housing having an air inlet and an air outlet in which the indoor air filter element sealing the intake side of the outlet separates.

p0056The invention further relates to a cab of a vehicle or a working machine comprising an inventive cabin air filter system and the use of a cabin air filter element or cabin air filter system according to the invention in a cab of a vehicle or work machine.

p0057Other possible implementations of the invention include not explicitly mentioned combinations of previously or below with respect to the embodiments of features or embodiments of the cabin air filter element or the cabin air filter system described. The skilled artisan will add or modify also individual aspects as improvements or additions to the respective basic form of the invention.

p0058Further embodiments of the invention are the subject of the dependent claims and described in the following embodiments of the invention. Furthermore, the invention is based on embodiments with reference to the beigele explained GTEN figures.

Brief Description of Drawings

p0059Shown here:<dl id="dl0001"><dt>Fig. 1:</dt><dd>a position of a fixed bed of activated carbon on a backing layer; </dd><dt>Fig. 2:</dt><dd>a first embodiment of accordance of two plies <figref idrefs="f0001">Fig. 1</figref> formed semifinished a Adsorptionsfilterlage;</dd><dt>Fig. 3:</dt><dd>a second embodiment of according of two plies <figref idrefs="f0001">Fig. 1</figref> formed semifinished product;</dd><dt>Fig. 4:</dt><dd>an accordance of a layer <figref idrefs="f0001">Fig. 1</figref> and a cover layer formed of a semi-finished Adsorptionsfilterlage;</dd><dt>Fig. 5:</dt><dd>a Adsorptionsfilterlage of two layers of a semi-finished product by <figref idrefs="f0001">Fig. 4</figref>;</dd><dt>Fig. 6:</dt><dd>a cabin air filter system with an embodiment of a cabin air filter element;</dd><dt>Fig. 7:</dt><dd>for example, the adsorption and desorption of water of an activated carbon material;</dd><dt>Fig. 8:</dt><dd>a cabin air filter system with a further embodiment of a cabin air filter element;</dd><dt>Fig. 9:</dt><dd>a cabin air filter system with a further embodiment of a cabin air filter element.</dd></dl>

Embodiment (s) of the invention

p0060The <figref idrefs="f0001">Figures 1-5</figref> is a possible structure of a Adsorptionsfilterlage apparent. <figref idrefs="f0001">Fig. 1</figref> shows a layer 100 of a fixed bed of activated carbon particles, comprising a support layer 101, and a bulk layer 102 with activated carbon particles.

p0061Two of these layers can be connected in various ways to give semifinished products, which may form a Adsorptionsfilterlage one or more layers. In the embodiment according to<figref idrefs="f0001">FIG. 2</figref> 100 arranged to one another such that in each case the fill layers 102 on one another, wherein a semi-finished product is formed, which is bounded on both sides of the support layers 101, two such layers. Several of these semi-finished products can be stacked to form a Gesamtadsorptionfilterlage.

p0062In the embodiment of <figref idrefs="f0001">Fig. 3</figref> 100 are arranged in the same orientation to one another, but it may also be a larger number 100 lying arranged one of such layers in this manner, two such layers. To form a completed Adsorptinosfilterlage, a cap layer 103 may be applied to the fill layer 102nd

p0063<figref idrefs="f0001">Fig. 4</figref> shows an embodiment of a preform 110 with a layer 102 of a fixed bed of activated carbon particles, which are applied to a carrier layer 101 and covered by a cover layer 103rd The semifinished product 110 can be either a single layer or in<figref idrefs="f0001">Fig. 5</figref> shown in a two- or multi-layer arrangement of superimposed semi-finished 110 form a Gesamtadsorptionsfilterlage.

p0064The bulk layers 102 are in the embodiments by means of fine networks of adhesive filaments with the respective carrier - connected and outer layers, but also other types of connection can be chosen.

p0065<figref idrefs="f0001">Fig. 6</figref> shows an embodiment of a cabin air filter system 70 in a cab 80 for vehicles, agricultural machinery, construction equipment and machines. The indoor air filtration system 70 includes a housing 50 having a first housing half 51 and a second case half 52 which are joined together by closure means 53rd In the housing 50, a cabin air filter element 1 (filter element) is arranged such that the entry side 61 is sealingly separated from the clean side 62nd The filter element has a peripheral seal 41 which axially by clamping of the filter element 1 between the housing halves, that is, in the flow direction, is pressed sealingly against a sealing face of the second housing half 60th The seal 41 is designed as a form-molded profile of closed polyurethane foam with a Shore hardness of 13 Shore A. The filter element 1 comprises an upstream side prefilter 10, which limits the raw side, a downstream fine filter layer 30, which limits the clean side and disposed therebetween Adsorptionsfilterlage 20. This can either be as shown on the left with reference numeral 21 of a multi-layer structure from each other horizontally arranged layers of fixed beds of activated carbon particles to support layers or right of it indicated be formed of an open cell foam with integrated rieselter activated carbon. According to the variant shown with reference numeral 21 in this embodiment, seven double layers of fixed beds in such<figref idrefs="f0001">FIG. 2</figref> shown lying one arranged, each having a support layer of spun-bonded melt-blown PET fibers (polyethylene terephthalate) having a basis weight of 85 g / m² and an air permeability 5500 l / m²s may include at 200 Pa. It is by means of an applied in thin fibers polyurethane-base adhesive, a bed of activated carbon beads of about 800 g / m² applied. This includes, at a relative humidity of 50%, a water absorption of about 9 percent by weight and a BET surface area of ​​900 m²/ G. The activated carbon particles have diameters in the range of 0.2 to 0.7 mm. According to the variant shown with reference numeral 22 the Adsorptionsfilterlage of activated carbon particles is formed that an open-celled (reticulated) foam polyurethane with a pore density of an average of 40 ppi (pores per inch) or 1.6 pores per millimeter comprises, in which the well up in is trickled variant 21 activated carbon particles used with fixed beds and. by means of a two-component adhesive based on polyurethane, are fixed in the foam Both variants have in the flow direction to an extent of 30 mm.

p0066The prefilter 10 is formed from a zigzag-shaped folded filter medium 11 with cellulose Epoxidimprägnierung having a basis weight of 90 g / m², A maximum pore size of 40 microns, an air permeability of about 200 l / m²s measured at a pressure difference of 200 Pa.

p0067The fine filter layer 30 is formed of a zig-zag folded HEPA fiberglass medium 31 with a layer of glass fiber paper with both sides laminated layers of a spunbond polyester. The glass fibers have different fiber diameter in the range of 800 nm to 5 microns. The basis weight of the fiber paper is preferably 80 g / m², The cover layer has basis weight of about 30 g / m² and thicknesses of about 0.2 mm and is connected by a calendar process with the glass fiber paper.

p0068Prefilter layer 10, fine filter layer 30 and Adsorptionsfilterlage 20 each have a sealing circumferential side band 12, 23, 32 of polyester non-woven and are superimposed position by means of a further side bands 40 to a filter element 1, wherein the side band 40, the sub-filter layers 10, 20, 30 connects sealingly , At the side band 40, the gasket 41 in turn is foamed with which the dirty side from the clean side in the housing 50 is separable.

p0069<figref idrefs="f0002">Fig. 7</figref> exemplifies based on isotherms, the adsorption and desorption of water of an activated carbon material. Is plotted on the x-axis represents the relative humidity in percent and on the y-axis, as to its mass of activated carbon water absorption W in mass percent. The measurement is usually carried out at normal temperature and normal pressure. The maximum water absorption is here with many types of activated carbon in the range of 20 to 50 percent by mass. Activated carbon usually shows at adsorption and desorption hysteresis behavior, as in<figref idrefs="f0001">Fig. 6</figref> shown. The solid line represents the profile of water absorption by adsorption and adsorption branch is called. The line represented by dashed lines represents the course of the water absorption by desorption and called Desorptionsast. According to the invention at a relative humidity of 50%, the water absorption W (50%) less than 10% by mass, preferably less than 5% by mass as measured on the adsorption branch of the isotherm pulled through illustrated here.

p0070<figref idrefs="f0002">FIGS. 8 and 9</figref> each show variations of the in <figref idrefs="f0001">Fig. 6</figref> illustrated embodiment, with the in <figref idrefs="f0002">Fig. 8</figref> Modification shown is characterized in that is formed as Adsorptionsfilterlage 20 a single or multiple layer of fixed beds of activated carbon, is folded which zigzag, in particular such that abut opposite fold limbs to each other, so that between the folds no gap is formed.

p0071In the <figref idrefs="f0002">Fig. 9</figref> Variant shown is the in <figref idrefs="f0001">Fig. 6</figref> illustrated embodiment, wherein there the fine filter layer 30 is disposed between the prefilter 10 and the Adsorptionsfilterlage 20th This has the advantage that the Adsorptionsfilterlage 20 is loaded with an even lower proportion of particles, reducing their effect can be obtained particularly well maintained. Of course, also both in this variant as well as in the in<figref idrefs="f0001">Fig. 6</figref> shown embodiment the Adsorptionsfilterlage as in <figref idrefs="f0002">Fig. 8</figref> be executed shown.