Abstract: The invention relates to a method of manufacturing a filter element for use in connection with e.g.

Abstract: An air filter comprising a filter pack comprising a folded nanofiber filter medium, fitted to a filter frame through a seal material, the nanofiber filter medium being a filter medium for an air filter, comprising a nanofiber filter medium which, when a filter medium face velocity is 5.3 cm/s, has a performance index of collecting target particle diameter of 0.3 ?m, 0.040 (1/Pa) or more, performance index of collecting target particle diameter of 0.1 ?m, 0.030 (1/Pa) or more, and performance index of collecting target particle diameter of 0.05 ?m, 0.050 (1/Pa) or more. By this, a high air volume and low pressure drop type high-performance air filter using a nanofiber filter medium can be provided.

Abstract: A filter arrangement includes a media construction comprising a corrugated sheet secured to a flat sheet rolled into a coiled construction. A frame and a first seal member are provided. The frame secures the first seal member to the coiled construction. The first seal member is preferably oriented to form a radial seal with a housing. A second seal member is secured to the outer annular surface of the coiled construction. The second seal member includes a gasket extension having first and second opposite ends; an attachment portion; and a protrusion extending from the attachment portion. The second seal member is preferably oriented to form an axial seal with a housing. Air cleaners preferably utilizing filter arrangements as described herein operably installed within housings. Methods of installing, filtering, assembling, and servicing preferably include arrangements as described herein.

Abstract: An air filter element partially-fabricated on site wherein one or more wire frames are fastened to one another to form a structure substantially conforming to the dimensions of the original equipment manufacturer's filter housing. One or more of the wire frames are flexibly attached to each other end-to-end by flexible attachment means, allowing the assembled filter unit to be inserted into the filter housing one frame at a time, with the frame sections yet to be inserted folded or directed off to one side, thus bypassing space restrictions. Flexible attachment means may comprise spring connectors. Also disclosed is an end-cap affixed to or formed at one or both ends of the filter element. The end-caps may also contain printed material, such as text or pictures, which may include instructions for use, identifying labels or symbols, or the like.

Abstract: A filter element and related method for separating particles from a particle laden unfiltered gas flow and a method for manufacturing such a filter element, wherein the filter element includes a first filter wall having a plurality of first through-flow openings for entry of contaminated unfiltered gas; a second filter wall disposed downstream of the first filter wall in the flow direction, and having a plurality of second through-flow openings for exit of clean gas; and an intermediate flow space disposed between the first and second filter walls, wherein the second through-flow openings are arranged in a displaced relationship with the first through-flow openings in the flow direction; the second filter wall has at least one impingement wall region arranged so that particles passing through the first through-flow openings at least partially impinge thereon; and at least one of the first and second filter walls has folds which extend alternately inward and outward relative to the intermediate flow space and

Abstract: The present invention provides filter units that, when joined together, allow joining portions thereof to be fixed together satisfactorily and can prevent air from leaking at the joining portions. A filter unit includes a filter medium that has been pleated and a frame that supports the circumference of the filter medium. The frame has a protruding part on at least one face selected from an upper face and a lower face thereof, with the protruding part being formed by allowing a part of the at least one face to protrude. The upper face is a surface of the frame that faces the upstream side relative to the flow of air that passes through the filter medium, and the lower face is a surface of the frame that faces the downstream side relative to the flow of air.

Abstract: A filter assembly for use with compressor assemblies such as oxygen concentrators, ventilators and other breathing apparatus including a compartmented housing member having at least one inlet opening, an outlet opening, a filter member, and an adjustment member associated with the at least one outlet opening for varying the size of the at least one outlet opening for adjusting the amount of ambient air entering the filter assembly.

Abstract: An air cleaner arrangement or assembly is provided. The air cleaner arrangement includes a serviceable filter cartridge. The air cleaner assembly also includes an arrangement for positioning the filter cartridge into a preferred, sealing, orientation and for securing the filter cartridge in that location. Preferred serviceable filter cartridges are provided, as well as methods of assembly and use.

Abstract: A high efficiency air filter for use in a standard return air grille is provided. Standard return air grilles possess filter receptacles for accepting air filters, a closeable cover with a cover flange for engaging air filters and a duct interface that leads away from the air grille to the remainder of the return air ducts. The air filter has a filter flange with a gasket that is sized to fit within the filter receptacle of the air grille, such that when the cover is closed, the cover flange seals against the cover and the filter receptacle. The gasket is affixed to a housing that is sized to extend beyond the filter receptacle into the duct extending beyond the return air grille. An extended pleat air filter is contained within and sealed to the walls of the housing such that air passing through the return air grille substantially passes through the air filter prior to entering the remainder of the return air duct.

Abstract: A filter cartridge, a safety element and fluid cleaner assembly are described. The fluid cleaner assembly generally includes a housing having a cover and a primary fluid cleaner section. The filter cartridge generally comprises z-filter media, arranged in a straight through configuration. Preferred cartridges include a seal gasket positioned to extend continuously around at outer perimeter of the straight through flow construction. The fluid cleaner assembly can have a precleaner positioned therein. Preferred features are described. Methods of assembly and use are also provided.

Abstract: The present invention discloses a fluid filter for screening carbon-microparticles exhausted from diesel engines, such filter has two types of structure, i.e. the plate type and the preferable tube type, which includes plurality of multilayer corrugated filtering rings and flat filtering rings, a central tube, and an outer casing; the innermost layer of the flat filtering rings is welded onto the central tube, and the outermost layer of the flat rings is welded onto the outer casing; the multi-layer corrugated filter rings are coaxially alternated within the flat filtering rings and formed with a zigzag manner, wherein side edges of each of the corrugated filtering rings are respectively welded onto neighboring flat filtering rings so as to form a continuous filter core with ‘Z’ shaped side endings, wherein two sides of the Z shaped side endings of said filter core are alternatively applied as fluid inlet and fluid outlet.

Abstract: The present invention may be used for framing a fluid flow filter pack. A first frame member may have a first border element with an open portion. The first border element may have four first side walls bendable along a line parallel to a peripheral edge of each of the first side walls. A second frame member may have a second border element with an open portion. The second border element may have four side walls bendable along a bend line parallel to an outer edge of each side wall. Each side wall of the second frame member may have a sealing flap bendable along the outer edge. The second frame member may be positioned on the first frame member with each side wall overlapping and attached to one of the first frame member side walls. The sealing flap may be bent to be adjacent to the second frame member side walls.

Abstract: A filter element, especially for filtering intake air for an internal combustion engine, which filter element is composed of a coiled filter, through which a flow of air passes axially, and which has an annular gasket on at least one end face, the annular gasket being connected to the filter element by a welded, glued, extruded or fused connection, such that the annular gasket is inserted into a suitably constructed receptacle in a filter housing and radially and/or axially positions the coiled filter. The annular gasket is arranged directly on the end face of the coiled filter and is pressed axially and/or radially into the receptacle of the housing.

Abstract: A self supported cylindrical corrugated filter. The corrugations of the filter define a first and second end. Two arcuate side walls join the first and second end. The filter has a substantially planar front surface and a substantially planar rear surface. The front and rear surfaces extend the length of the filter. The arcuate side walls have a plurality of overlapping folded flaps. Each one of the plurality of flaps is joined to at least one adjacent flap from the plurality of flaps to form the self supported filter.

Abstract: An air filter media construction or arrangement is disclosed. The air filter media construction or arrangement includes strips of media comprising corrugated sheets secured to facing sheets and forming inlet and outlet flutes secured to one another in a stack. A preferred projection/receiver arrangement is described. Methods of assembly and use are also provided.

Abstract: A unified pleated filter arrangement including a unified method and product wherein successive pleat flanks are spaced by communicably facing increments of spacing material with the pleat flanks being a selectively spaced and uniformly level geometric configuration.

Abstract: A filter assembly for use in a cleaning appliance has a first filter portion surrounded by a deformable rim. The first filter portion consists of a non-woven medium. The filter assembly (also includes a second filter portion located downstream of the first filter portion. The first filter portion and the second filter portion are held directly adjacent one another by means of the deformable rim. The filter assembly further includes a third filter portion located upstream of the first filter portion and consisting of a mesh material. The first filter portion and the third filter portion are held directly adjacent one another by means of the deformable rim. The filter assembly has a tab located on a surface thereof to facilitate removal of the filter assembly from a filter housing or a vacuum cleaner.

Abstract: A filter is provided by pleated filter media having a plurality of pleats defined by wall segments extending axially along an axial direction along an axis and extending transversely along a transverse direction between first and second sets of pleat tips at first and second sets of axially extending bend lines. The pleated filter media spans laterally along a lateral span along a lateral direction, with the wall segments being spaced from each other by lateral gaps. The pleats have a pleat depth along the transverse direction along the wall segments between the first and second sets of pleat tips. The pleat depth varies as the pleated filter media spans laterally along the lateral direction.

Abstract: An air filter insert including at least one filter element (2; 4; 11) and a seal (3; 7) extending along outer edges of one side of the filter insert (2; 4; 11) and via which the filter insert is sealingly seated against housing sections (5, 6) of a surrounding filter housing. The filter insert (2; 4; 11) is configured such that the air can easily flow into or out of the structural space on the one side of the filter element with a minimum pressure drop. The filter insert (11) may be at least partially covered on the inflow and/or discharge side by a semi-permeable component (12), which at least partially equalizes the pressure distribution in the air stream.

Abstract: A method of removing moisture from inlet air flowing to a gas turbine. The method comprises the steps of providing a housing for supporting a primary air filter. The housing is operably connected with the gas turbine. A hood connected with the housing is provided. The hood has a surface disposed at an acute angle relative to horizontal. Inlet air flow is directed into a preliminary filter supported above the hood and extending in a downward direction. The preliminary filter comprises media capable of separating moisture from the inlet air flowing through the preliminary filter at an exterior portion of the preliminary filter. Separated moisture agglomerates into a drop incapable of being carried by the flow of inlet air so the drop falls onto the hood to be directed out of the flow of inlet air.

Abstract: A filter cartridge arrangement is provided which includes a media pack comprising Z-filter media, a preform and a housing seal member. Improvements in the preform and seal member are described which include: a single beveled surface of the seal member to facilitate installation; and, an inside region of the seal member having a tip adjacent in inwardly directed lip of the preform, to control flash during molding. A variety of media pack configurations and features are described.

Abstract: A filter arrangement includes a filter element, a frame construction secured to the filter element, and a handle member secured to the filter element. In preferred embodiments, the handle member is secured to the frame construction. Preferably, the filter element includes a central core member, wherein fluted filter media is coiled around the central core member. Preferably, the central core member includes a plurality of corrugations, wherein the corrugations mateably engage at least some flutes. Preferably, the handle member is integral with the central core member, and also includes a fastening member for connection to a frame construction on the filter element. Methods for cleaning air and servicing an air cleaner preferably include constructions as described herein.

Abstract: Wet laid, nonwoven, fibrous mats suitable for making MERV 6 or higher filters, and methods of making the nonwoven mats are disclosed. The mats include a blend comprising a major portion of glass fibers and a minor portion of man-made polymer fibers, such as polyester fibers, the fibers being bound together with a cured binder having a Tg in the range of about minus 30 to about 50 degrees C. The mats are pleated prior to assembling the filter in conventional manner. The only fibrous mat in the filters is wet laid fibrous nonwoven mat and the pleated filter media needs no other means of support in the filter frame.

Abstract: A filter adapted to be placed within a distal end of a hose for use in products such as a convective air warming system for a patient to reduce airborne contamination. A method of providing filtered airflow to a coverlet of a convective air warming system that includes installing a filter in a distal end of a hose of the convective warming system.

Abstract: Air cleaner assemblies and components therefor are described. An example first or main filter cartridge is described which includes a media pack comprising strips of fluted material secured to facing sheets, oriented in a stack. The media pack defines opposite inlet and outlet flow faces, with flutes extending in a direction therebetween. The media pack is non-removably secured within a filter cartridge housing, at a location between opposite sections of a shell, typically secured thereto with an adhesive. The shell also defines a closed end, spaced from, but in overlap with, the outlet end face of the media pack. The closed end is typically curved and the shell typically provides either a d/b-shape or a u-shape. The filter includes an end member, with a outlet flow aperture arrangement therein, allowing for outlet flow from the filter cartridge in a general direction orthogonal to air flow through the media pack.

Abstract: Wet laid, nonwoven, fibrous mats suitable for making MERV 6 or higher, filters, and methods of making the nonwoven mats filter media are disclosed. The mats include a blend comprising a major portion of glass fibers, a minor portion of man-made polymer fibers, such as polyester fibers and about 0-30 wt. percent of chemically cross linked bleached Kraft pulp the fibers, and optionally fully bleached softwood Kraft pulp, the fibers being bound together with a cured binder having a Tg in the range of about minus 30 to about 50 degrees C. The mats are pleated prior to assembling the filter in conventional manner. The only fibrous mat in the filters is wet laid fibrous nonwoven mat and the pleated filter media needs no other means of support in the filter frame.

Abstract: A filter pack includes filter media formed into a filter structure having a front, a back and at least one side surface; and a frame adhered to the at least one side surface and comprising an adhesive and an adhesive carrier. The adhesive carrier can be a sheet of material which can be impregnated with the adhesive, one example being a sheet of the filter material itself. The adhesive carrier can alternatively be a single use tray mold for holding the adhesive while it cures, and which is left into the final product.

Abstract: A filter element comprises a filter medium (1) with an inflow and an outflow side wherein at least one channel (2) which is variable in its dimensions is associated to the filter medium (1). An arrangement comprises a filter element and a flow channel, wherein the flow channel can be at least partially closed and opened by means of the filter element. Such a filter element and such an arrangement solve the objective to realize a filter system which ensures an engine-friendly operation mode and a long service life of the filter element.

Abstract: A dual pleated air filter according to the present disclosure may include two or more generally parallel, pleated filter elements layered perpendicular to the influent air stream and having the pleats of adjacent filter elements oriented orthogonally. Within each pleated filter element are an influent mesh layer and a corresponding effluent mesh layer for supporting filter media and one or more layers of filter media are located between the influent and the effluent mesh layers. The relative orientation of pleats of adjacent elements may range from parallel to perpendicular.

Abstract: An air filter arrangement is disclosed. The air filter arrangement includes strips of media comprising fluted sheets secured to facing sheets and forming inlet and outlet flutes secured to one another in a stack. Media pack arrangements including such stacked media with peripheral, perimeter, housing seal arrangements are described. Also described are air cleaners including the filter cartridges. Methods of assembly and use are also provided. Also, systems of use are described.

Abstract: A system is disclosed for a plate-shaped filter element (2) in a gas filter housing (1). The filter element (2) has filter material (3), which is folded in a zigzag shape, having filter folds closed at the front edges, and the closure (4) being made of essentially the same filter material which forms the filter folds, and having an edge area (5) projecting outward on both sides, and in which the two edge areas (5) are inserted into the housing (1) having insert struts (7), on the sides assigned to the end folds of he plate-shaped filter element (2), which engage the end folds (8) and ensure a leakage air rate of 0 to 4 m3/h at a differential pressure of at least 200 Pa.

Abstract: A panel filter frame and panel filter are provided. The panel filter frame is made from a one-piece die-cut blank of material. The die-cut blank includes a grill portion, four sidewall portions and four flap portions all integrally connected. Individual sidewall portions are interposed between a side of the grill portion and one of the four flap portions. The plurality of portions of the die-cut blank are interconnected at fold lines. The frame is formed when the die-cut blank is folded about the fold lines and the portions are secured in the folded position by at least a plurality of interlock receptacles formed in the terminating folded portion of the die-cut blank.

Abstract: An improved air filter for filtering particulate matter from the air flow of a ventilation system and a method for manufacturing the air filter. The air filter comprises an air filter media having a top surface, a bottom surface, and a perimeter. The filter media preferably is a pleated media. A frame surrounds the perimeter of the media. The frame is preferably made of Styrofoam or similar lightweight foaming material. The foam material becomes bonded to the media such that air leakage between the foam material and the media is prevented when the air filter is in use in the ventilation system. Reinforcing ribs may be provided on the media to provide additional structural support for the filter.

Abstract: A filter assembly for fuel is disclosed. The assembly includes a housing and a filter element located in the housing and held in place by a spring. In the space between the inner wall of the housing and the base of the filter element a compressibly resilient element is located which absorbs hydraulic pulses, the filter assembly is subjected to.

Abstract: A filter element includes a filter web pleated in an essentially zigzag manner and made, in particular, of a nonwoven material, for insertion into a holder such as a filter frame and/or a filter housing, having at least one end-positioned wall of an essentially flat design. The filter element includes at least one end face, viewed in the direction of the pleats. To achieve a tighter seal, the end face of the filter element is curved outward in a defined convex manner, and the filter web material is selected and/or its end face conditioned so that, when inserted into the holder, the end face of the filter web may be placed leak-tight against the end wall of the holder without corrugation under elastic pre-tension.

Abstract: A self-supporting, pleated filter including a plurality of pleats in a filter media that extend along a front face and a rear face. The pleats include a plurality of pleat tips and sloping side surfaces generally perpendicular to the direction of pleating. At least one planar reinforcing strip oriented in the direction of pleating is bonded to the pleat tips on the front face. At least one reinforcing member is positioned along the rear face of the filter media. The reinforcing member may be a reinforcing strip oriented in the direction of pleating and bonded to the rear face of the filter media. A second planar reinforcing strip may optionally be bonded to the reinforcing strip pleat tips. The reinforcing member, the first reinforcing strip and the second reinforcing strip can be aligned to form a truss structure.

Abstract: The invention provides a renewable composite filter media for removal of particles from a fluid stream. The filter media includes a membrane filtration layer comprising a porous polymeric membrane having an upstream side and a downstream side relative to the direction of fluid flow, a first depth filtration media layer having an upstream side and a downstream side relative to the direction of fluid flow, the first depth filtration media layer being disposed on upstream side of the membrane filtration layer; and at least one additional depth filtration media layer removably attached to the upstream side of the first depth filtration media layer. In this aspect, the first depth filtration media layer may be removably attached to the membrane filtration layer.

Abstract: An air filter is disclosed including a particulate filtration portion for filtering particulates from inlet air flow. The filtration portion is produced from a first sheet of air filtration material folded into a pleated volume that is bounded by a plurality of sides including a pair of opposite folded sides, through which air flow passes, at least one pleated side that extends between the folded sides, and at least one end side at each end of the series of pleats. The pleated sides and end sides meet along at least one corner edge of the pleated volume, and the pleated side meets each of the folded sides along side edges that extend along the series of pleats. The air filter also has a side sealing portion for forming a particulate seal within the housing along the pleated side. The sealing portion is made from a second sheet of air filtration material that covers the pleated side and projects beyond the pleated side to provide a flange that extends upright from a folded side along a corresponding side edge.

Abstract: An air filter element partially-fabricated on site wherein one or more wire frames are fastened to one another to form a structure substantially conforming to the dimensions of the original equipment manufacturer's filter housing. One or more of the wire frames are flexibly attached to each other end-to-end by flexible attachment means, allowing the assembled filter unit to be inserted into the filter housing one frame at a time, with the frame sections yet to be inserted folded or directed off to one side, thus bypassing space restrictions. Flexible attachment means may comprise spring connectors. Also disclosed is an end-cap affixed to or formed at one or both ends of the filter element. The end-caps may also contain printed material, such as text or pictures, which may include instructions for use, identifying labels or symbols, or the like.

Abstract: A filter element has a fold pack having sides. A lateral strip at least partially surrounds the sides of the fold pack. The lateral strip is made of thermally deformable lateral strip material. At least one guide section projects laterally from the filter element and is made from the thermally deformable lateral strip material. In a method for producing such a filter element, a fold pack is at least partially secured with a lateral strip made of a thermally deformable lateral strip material and the lateral strip material is then thermally deformed to a guide section that projects laterally from the filter element.

Abstract: A filter element has a fold arrangement and a shaped seal extending about at least one section of a circumference of the fold arrangement. The shaped seal consists of a thixotropic sealing material or at least contains such a thixotropic sealing material. The thixotropic sealing material is thixotropic PUR or thixotropic silicone or a mixture of both.

Abstract: A filter device having a filter element which has at least one end disk (19) having axially extending elevations (20) configured in the form of at least one recognizable character, in which the elevations correspond in configuration to passages (35-37) through an intermediate element (23). Behind the intermediate element there is an element (24) which faces the housing (10) of the filter unit and is provided with axially projecting appendages (30, 31) which extend into the passages (35-37) of the intermediate element (23). Intermediate element (23) and element (24) are axially movably mounted on a central mandrel (17), and the appendages (30, 31) can be pushed axially by the filter element (12) out of the passages (35-27) of the intermediate element (23) so that intermediate element (23) and element (24) can rotate relative to each other and move axially and the filter element can be moved to its fully installed position.

Abstract: An axial flow filter element having alternating flat and pleated layers of fluid permeable filter media which form channels with an open cross section, one end of a first group of channels and the other end of a second group of channels being tightly sealed such that fluid being filtered must pass through one of the filter layers to pass through the filter element, a peripheral seal for sealing the inflow side of the filter from the outflow side in a housing, and a support body arranged in the filter element surrounded by the channels and extending axially at least to one end face of the filter element; at least one end face of the filter element having a spacer for maintaining the end face at a distance from a supporting surface on which the filter element may be placed during handling to prevent direct contact between the end face and the supporting surface.

Abstract: Foldable filter assemblies and methods of use thereof are disclosed. An air filter assembly including a frame having opposed substantially rigid end members and a flexible side member, the end members being connected to the flexible side member, and an air filter media connected to and disposed within the frame such that the frame is adapted to be disposed in a planar use position, and the end members of the frame are adapted to be moved toward each other prior to installation into the planar use position.

Abstract: An air cleaner has a casing body having an opening that communicates with a carburetor. The casing body includes a fitting part having an inner wall surface and a bearing surface. A sealing frame is inserted into the casing body and engages the fitting part of the casing body. The sealing frame has an outer peripheral part with an outer peripheral surface that is held in contact with the inner wall surface of the fitting part, a rear surface that is held in contact with the bearing surface of the fitting part, a front surface, and a groove formed in the front surface along a circumference thereof. A filter is disposed internally of the sealing frame. A cover covers the filter and the sealing frame.

Abstract: A reducing apparatus 16 for carbon particles PM is provided with one or more filters 19 of a wire mesh structure. The filter 19 is formed in a substantially short column-shape and is provided with a central through-hole 21 and a pair of exhaust ducts 26. The filter 19 is situated within an outer cylindrical casing 4 on an axis perpendicular to the axis of the outer cylindrical casing 4. Exhaust gas 1 discharged from a diesel engine flows from an outer periphery 22 side of the filter 19 to the central through-hole 21 side, wherein the carbon particles PM contained in the exhaust gas 1 are captured, burned and reduced. A plurality of filters 19, each formed in a hollow cylinder-shape, can also be provided side by side in the same direction as the axis of the outer cylindrical casing 4.

Abstract: A mounting structure for an air cleaner on a combustion engine according to the present invention includes an engine cover (9) for covering at least a portion of the combustion engine (E). The cover (9) includes an air cleaner casing (81) having an opening and an air cleaner cover (83) for covering the opening of the air cleaner casing (81). Flanges (81f, 83f) are formed in respective joint portions of the air cleaner casing (81) and the air cleaner cover (83). The mounting structure also includes a slider (10) movable between a disengagement position and an engagement position in a direction parallel to the joint portions. This slider (10) when moved to the engagement position connects the flanges (81f, 83f) of the air cleaner casing (81) and cover (83), but when moved to the disengagement position the slider (10) enables the cover (83) to be released from the casing (81).

Abstract: A filter system including a method for self cleaning the filter system of an electronic equipment enclosure where air flow is monitored either by monitoring fan performance of air flow velocity through the enclosure. The system includes two filters elements, an upstream ASHRAE or HEPA filter element to block particulate matter and a downstream PTFE filter element to block water vapor. The ASHRAE or HEPA filter element is relatively inexpensive and easy to clean. The PTFE filter element is more expensive and difficult to clean. Thus, the cheaper filter is used to protect the more expensive filter from contaminants and to increase its useful life.

Abstract: Collapsible filter assemblies for use with pleated or other filter media are disclosed. A collapsible filter assembly can include at least one filter element including a filter media supported within a collapsible filter frame. The filter frame can include a number of frame members each including a number of frame panel sections hingedly connected to each other. Each frame member can be configured to bend or fold outwardly away from the sides of the filter media to permit the filter frame to be actuated between a collapsed position and an expanded position. A number of elastic members can be coupled to opposing sets of frame members in order to bias the filter frame in the expanded position, causing the filter assembly to self-expand when removed from its packaging. During installation, such auto-expanding feature reduces the amount of time required for the installer to place the filter assembly into service.

Abstract: A filter has a housing and a filter element with a first filter medium, wherein the filter element is arranged in the housing. A releasable lid is provided at an end face of the housing and closes off the housing. The releasable lid and the filter element together form a unitary component and the releasable lid forms a terminal disk at a first end of the filter element. The releasable lid forming the terminal disk of the filter element is glued to an end face of the first filter medium. The unitary construction of the filter element and the lid simplifies changing the filter element.