AIR FILTER CARTRIDGE AND METHOD FOR ASSEMBLING A CARTRIDGE INCLUDING TWO FILTER ELEMENTS

Abstract

The air filter cartridge (CF) includes a support frame (7) for attaching two filter elements (11, 12) in a superimposed state, on either side of an inner rim of the frame, using the same adhesive material that can be poured in a single application step carried out on one side of the rim. A perforated annular wall portion separates a first bonded zone (ZC1) where the first filter element (11) is attached from a second bonded zone (ZC2) where the second filter element (12) is attached. The adhesive material flows smoothly from one zone to the other through the holes in the rim. A bonding interface (30) is formed between the filter elements, combining the perforated wall portion and the solidified layer of adhesive material in which the respective ends of these elements are embedded. Figure 3

Description

Title of the invention: CARTRIDGE FOR AIR FILTER AND METHOD FOR ASSEMBLING A CARTRIDGE INCLUDING TWO FILTER ELEMENTS Technical field

[0001] The invention relates to the field of air filters, in particular filters intended to purify the supply air of internal combustion engines or a fuel cell generator, for example for use in a motor vehicle. The present disclosure relates more particularly to a filter cartridge having two filter elements and to a method of assembling such a filter cartridge. It also relates to an air filter comprising a housing with two filter elements which can be superimposed within a cartridge arranged internally in the housing. Prior art

[0002] In air filters for motor vehicles, it is common to house a filter element inside a reusable housing. The filter element may include several filtration layers, for example a filter layer for separating dust (including particles visible to the naked eye) and then one or more layers dedicated to the separation of fine particles and / or chemical contaminants (including the SO2 contaminant or other common contaminant, for example in the case of filtration for a fuel cell).

[0003] Document US 2017 / 0239604 provides for example to accumulate a certain number of filtration layers in a filter part. To allow the use of a filter cartridge in a housing with ease of assembly and an optimized and durable filtering capacity, the use of pleated media may also be required. When the air filter is to be combined with a fuel cell or sensitive generation area, several filter layers are usually required to protect this cell / area from pollutants coming from outside.

[0004] In any event, there is still room for improvement in facilitating the assembly of a cartridge which may present increasing complexity in order to enable good air filtration, in particular when it comes to cartridges combining at least two filter elements. Summary

[0005] In order to improve the situation, an air filtration cartridge is proposed, capable of cooperating in a housing of an air filter (cartridge for an air filter having a housing) including an inlet for the admission of a raw air flow and an outlet for the purified air evacuation, the cartridge comprising: - a first filter element; - a second filter element; - a common support frame for supporting the first filter element and the second filter element by making them integral with each other, this frame extending annularly around a longitudinal axis and having an inner face from which a rim covered with a bonding material is formed, so that the rim includes a first surface for receiving a bonding layer based on the material for the first filter element and a second surface for receiving a bonding layer of the same material for the second filter element, the second surface being oriented opposite the first surface, knowing that the first receiving surface and the second receiving surface are provided, in the rim, on an annular portion of perforated wall allowing migration from one to the other of the receiving surfaces, of the fluid bonding material (before solidification or stabilization, for example while the bonding material has just been heated or is still in a sufficiently hot state), under the effect of gravity, by filling holes distributed in the annular portion of perforated wall.

[0006] Thanks to these provisions, the assembly of the cartridge can be made easier, for example by eliminating a glue pouring step (single glue casting step). A superimposed configuration of the filter elements is effectively achieved with airtightness in the transition zone between the two elements which can be designed separately. A separate preliminary design of these two filter elements can be of interest in terms of logistics and / or to make the filtration enabled by a more specific element, depending on the needs. The attachment to the frame can make it possible to produce a superimposed configuration, in particular such that the second filter element is superimposed on the first filter element to make it possible to form, in the second filter element, at least one intermediate filtration layer between an outlet face of the first filter element and the outlet of the housing in a mounted state of the cartridge.

[0007] The frame may be provided with holes for the fluid flow of the material only in the annular wall portion which is for example entirely surrounded by an air-impermeable side wall (of the frame). All or part of the holes may consist of slots.

[0008] In embodiment options, the cartridge may have one or more of the following features: - the first filter element has an annular peripheral support member and a first filtration medium which is connected to the peripheral member, preferably by being fixed to an inner face of the peripheral member. - the second filter element has a belt and a second filtration medium which is connected to the belt, preferably by being fixed to an inner face of the belt; - the peripheral member is embedded in a first sub-layer of the material running along the first surface; - the belt is embedded in a second sub-layer of the material running along the second surface. - filling the holes with the material makes it possible to create a discontinuous intermediate sub-layer directly connecting the first sub-layer to the second sub-layer. - the belt and the peripheral member may have the same shape and the same dimensions, with the possible exception of a difference in height (measured parallel to the longitudinal axis of the frame). - the first sub-layer can fill the lower cavity, while the second sub-layer can fill the upper cavity. - when the cartridge occupies a filtration chamber, in the housing, an intermediate space between the two filtering elements, internal to the cartridge, is separated from the upstream filtration zone (zone outside the cartridge) by the first filtering element and separated from the downstream filtration zone (zone outside the cartridge) by the second filtering element. - the rim projects radially inwards and includes a T-section profile, so as to delimit, with the inner face of the frame, a lower cavity and an upper cavity. - the bonding material may fill the upper cavity and the lower cavity by flow from one side of the frame only, for example near / along an inner circumference of the frame. - the bonding material has a hot-melt adhesive formula, possibly without water or solvent. - the bonding material is a two-component polyurethane glue or a two-component epoxy glue, with temporary fluidity (linked for example to the action of a hardener associated with the resin). - the holes are made in the form of oblong perforations. - the frame has a circumferential external relief, preferably projecting radially on the outside of the frame. - the cartridge including an annular seal which comprises a first portion covering the relief from below, as well as a second portion covering the relief from above. - the external relief may have a first side located substantially at the same level than the inner rim.

[0009] In embodiments, the filter cartridge carries a peripheral seal, which may include at least one of the following features: - the cartridge is removably received in the housing component, for example by using a seal as a contact part with a circumferential support provided internally in the housing component. - the joint includes a generally U-shaped cross-section. - the seal has two sealing lips, for example opposite each other. - a first annular lip of the seal connects from below to the first covering portion, projecting downwards and outwards to a free edge of the first lip. - a second annular lip of the seal connects from above to the second covering portion, projecting upwards and outwards to a free edge of the second lip.

[0010] In embodiments, the cartridge has one or more of the following features: - the cartridge includes a single part constituting the support frame, provided with an annular gluing housing provided in the inner rim, for the assembly of the filter elements, this part being also able to form an outer circumference of the filter cartridge. - the frame may have a side wall with at least four sides and an annular inner rim forming a support from below for the second filter element which may optionally extend into a hollow in the cover.

[0011] According to another aspect, there is provided an air filter provided with a filter cartridge as mentioned above, this cartridge being housed in a housing delimiting a filtration chamber, having a cover to make this filtration chamber accessible in order to allow replacement of the filter cartridge. The air filter thus comprises a filtering part, a housing delimiting a filtration chamber between a component of the housing and a cover, with the filtering part which includes said filter cartridge with an ability to be removably mounted in the filtration chamber, in particular by resting from above on a seat area formed by an inner edge of the component which includes a bottom of the housing.

[0012] In such a filter, the housing having a cover for closing an opening of the component through which at least the first filter element of the filter cartridge is placed in said component, facing the bottom. In addition, the housing component may typically include the inlet for the admission of raw air flow, the outlet for the discharge of purified air being provided in the cover, so as to delimit in the filtration chamber a downstream zone, between the second superimposed filter element to the first filter element and a top of the cover located opposite the bottom.

[0013] According to one option, the cover is hinged to the component by a hinge connection and capable of being closed and locked in a position for closing the opening, which is a position in which locking means maintain a clamping between the component and the cover with a crushing of a peripheral seal of the cartridge between a shoulder or groove of the component and a lower end of the cover.

[0014] According to one aspect, there is also a method of assembling an air purification filter cartridge including two filter elements, by using a (typically rigid) frame, comprising the steps essentially consisting of: - provide the frame which extends annularly around a longitudinal axis by having an inner face from which is formed a rim accessible from two opposite axial ends of the frame, the rim being formed in a portion of perforated transverse wall having holes or passage slots; - gluing the edge by depositing a bonding material, using a first opening provided in one of the two axial ends, by depositing at least one fluid dose (fluidized when hot or before hardening) of bonding material, so as to distribute a quantity of the bonding material, part of which is used to obtain at room temperature a so-called upper solid layer along the top of the edge; - allowing excess fluid bonding material from said quantity to flow into the holes or passage slots, in order to allow distributed bonding on top and along a bottom of said rim, by limiting the downward flow of the bonding material by a counter-surface of a tool arranged directly above the rim in an annular region underlying the rim, whereby the bonding material can also form a so-called lower solid layer at room temperature; - producing two fixings on said frame using the bonding material, by bringing each of the two filter elements into contact with a corresponding layer chosen respectively from the upper layer and the lower layer, obtaining a first annular seal between the frame and the first filter element and a second annular seal between the frame and the second filter element.

[0015] This method can simplify assembly, for example by avoiding having to separately control the temperature of two bonding materials deposited separately for fixing. It is understood that the first fixing can be carried out on the side from which the entire quantity of bonding material was poured. Eventually, the quantity of material used can be optimized, knowing that the portion of the transverse wall, generally annular, can be thin / limited in its thickness which can be less than or equal to the thickness of the side wall of the frame.

[0016] According to options, at least one of the following provisions may be provided: - between the respective start of the two fixings, a sufficient time elapses to ensure that the filter element is kept bonded first to the bonding material. - between two fixings, the frame and the tool are separated from each other, the counter surface of the tool remaining in contact with the lower layer in a still fluid state during a first fixing intended to fix one of the first and second filter elements. - a second attachment is provided after a turning of the frame followed by a removal of the tool, in order to attach the other of the first and second filter elements and thus obtain a superimposed configuration of the second filter element and the first filter element which are separated by the rim (inner rim). - one of the two fixings is made in a cavity of the rim, the holes of the perforated annular portion opening axially through the bottom of this cavity. - the other of the two fixings can be made in another cavity of the rim, possibly with a T-section profile provided in the rim in order to allow the internal demarcation of one and the other of the cavities. - the two cavities are separated (axially along a direction of the longitudinal axis of the frame) from each other by the openwork wall portion. - the bonding material is a glue which can be based on a hot-melt thermoplastic. - the material is dispensed for example by a gun in order to ensure the deposition of a constant and stable volume of glue in the cavity of the frame, from above while the counter-surface can be placed against a flank / internal axial projection of the rim, so as to close the opposite cavity located lower down.

[0017] A method of assembling an air filter / filtering device as mentioned above (device with a housing capable of being arranged vertically), may provide for: - delimit, by a component / housing body, a housing accessible from above via an opening, the component also having a fixing bracket including a gripping edge located higher than the opening; - movably mounting, by a hinged connection, a cover on one side of said component, this side forming part of a border of the opening, whereby the component and the cover constitute the housing; - providing separation means, comprising at least one air-permeable medium, in an interior compartment delimited by the housing component, the separation means belonging to the aforementioned filter cartridge being mounted removably and in a single block in said compartment by insertion through the opening, a first filter element of the filter cartridge making it possible to retain particles and dust on the side opposite an outlet provided on the cover; and - in order to allow locking of a closed position of the cover, in which the opening is covered by a closure part belonging to the cover, actuate, by use of a pivot connection, an upper part of a locking element further having a lower anchoring portion engaging under a gripping edge secured / integrated with the housing component, in a removable manner to maintain a clamping between the housing component and the cover, typically with crushing of a peripheral seal carried by the cartridge.

[0018] In one embodiment, the cartridge is used in a housing for filtering the air supplied to a battery or fuel cell system. In another application, the device is used to filter the air supplied to an air supply circuit of an internal combustion engine, in particular for a vehicle engine (e.g., an automobile).

[0019] In options, the (peripheral) seal provided on the filter element is capable of applying, when there is no longer any clamping exerted by the second attachment system, a separating force to the filter element to slightly raise the latter and / or to push the cover upwards. The seal being no longer crushed, a return effect towards the nominal shape of the seal (which is a shape memory seal) can allow an expansion effect in the direction at least along a vertical / perpendicular direction to the hinge connection and perpendicular to the plane of the opening of the housing component. Brief description of the drawings

[0020] Other characteristics, details and advantages will appear on reading the detailed description below, and on analyzing the attached drawings, in which: [Fig.l] shows in section a filter cartridge with two filter elements, in a state mounted in an air filter housing. [Fig.2] is a perspective view of the air filter of [Fig.l], the housing of which can house a filter cartridge in a removable manner to allow it to be replaced by moving the cover. [Fig.3] is a perspective view showing the cartridge of [Fig.l], with the two filter elements mounted through the frame shown here, with a gasket, shown transparently to illustrate the bonding area obtained on the inner side of the frame. Figure 4A is a perspective view, from above, of a frame before gluing which may correspond to the frame of the cartridge of [Fig.3], the frame having a portion of openwork wall provided in an interior rim of this frame. Figure 4B illustrates a detail of the frame structure of [Fig.4A], in an example using two cavities having the same or similar width at the inner rim. [Fig.5] illustrates a detail of the cartridge of [Fig.3], with a section to illustrate two fixing zones distributed on either side of the inner edge of the frame. Description of embodiments

[0021] Below is a detailed description of several embodiments of the invention with examples and reference to the drawings. In the various figures, identical references indicate identical or similar elements.

[0022] With reference to Figures 1 and 2, there is illustrated a filtration device 1 provided for the purification of a raw air flow F (possibly pre-filtered) coming from the outside, this device / filter being in the suction line of an internal combustion engine or an engine component, for example an accumulator or an energy source (a fuel cell, hydrogen for example). This device 1 can be placed in an air intake line or circuit for an engine. In the case of a motor vehicle, the device 1 can be arranged in the line, as the last filter before an intake manifold of an engine, a similar inlet for receiving purified air from an engine or a housing of an electrochemical generator.

[0023] As visible in [Fig.2], the device 1 comprises a housing 2 provided with an inlet 3 and an outlet 4. A housing body or component 14 makes it possible, for example, to define a bottom 2a of the housing 2. A cover 10 can be mounted movably or removably on the component 14. This cover 10 covers the component 14 from above in the non-limiting example illustrated. A domed configuration can be used to increase the interior volume of the housing above a junction J. More generally, this interior volume makes it possible to install a filter cartridge CF. In mounting options, provision is made in particular for a suspended and / or spaced position of the filter cartridge CF relative to the bottom 2a, as in the case visible in [Fig.l].

[0024] The CF cartridge may include a support structure, here in the form of a frame for delimiting an outer perimeter of the CF cartridge. The frame 7 may also serve as a rigid gripping portion for gripping the CF cartridge. The frame 7 may extend in an annular manner around a longitudinal axis X, as shown in particular in [Fig.4A], extending between an annular lower end 7a and an annular upper end 7b. A face F1 formed by a first filtration medium 5, which may be oriented opposite the bottom 2a in the mounted state, may constitute an inlet of the CF filter cartridge. This face F1 is axially spaced from the bottom 2a, so that there is provided, under this face F1: - an air circulation sub-zone (raw air) adjacent to inlet 3 formed in component 14; and - optionally, a sub-zone forming an air reserve shifted laterally by report to entrance 3 and delimited between bottom 2a and face Fl.

[0025] More generally, the interior volume of the housing 2 includes a filtration chamber. The filtering part of the device 1, housed in the interior volume, is here a cartridge CF which may comprise separation means of the type including filtration media 5, 6 and making it possible to separate an upstream zone Z1, provided in the filtration chamber and communicating with the inlet 3, from a downstream zone Z2 communicating with the outlet 4. The zone Z1 may be arranged below the cartridge in embodiments of the housing 2 with the inlet arranged lower than the outlet. A flow of purified air F' emerges via an outlet face F2 of the separation means / filtration media 5, 6, passing through the downstream zone Z2 and reaching the outlet 4. One of the filtration layers (at least) of the filter cartridge CF makes it possible to retain aqueous liquids, each layer being permeable to air.This cartridge makes it possible to delimit a clean zone, corresponding to downstream zone Z2 which, in typical options, extends in particular into a hollow of the cover 10. In housing variants, the inlet 3 and outlet 4 can be arranged at comparable height levels or with one outlet located lower in the housing 2 in the mounted state.

[0026] The filtration chamber may be surrounded by a side wall of the housing 2, which is a generally tubular wall, possibly with four sides. The housing component 14 forming the bottom 2a of the housing 2 may at least partly form this side wall. The housing component 14 may have two sides, a front face and a rear face opposite the front face. A wide opening 02 is formed at the upper end of the housing component 14, this opening 02 being delimited by an annular border which may include a similar flange or rim (typically projecting outwards).

[0027] The housing 2 of the filter 1 is closed during operation, and can be opened by having a cover 10 hinged via a hinge connection 8 on the housing component 14. The hinge connection 8 may correspond to a first attachment system of the housing 2. In this non-limiting case, a second attachment system is further provided to allow the locking of the cover 10 with a tightening of this cover 10, for example in order to keep it closed against the edge formed at the upper end of the housing component 14. The unlocking of the cover 10 may be allowed by at least one locking element MV, MV' possibly including one or more clips.

[0028] The component 14 may be configured with an internal shoulder or internal support means adapted to support the cartridge from below, so that the filter cartridge CF is in its predefined position relative to the component 14 before the cover 10 is placed in the position for closing the opening 02. In variants, the filter cartridge CF may be previously fixed, by example nested, in the cover 10, before occupying its final position in the filtration chamber. It may be provided that the frame 7 of the CF cartridge carries the fixing interface in contact with the component 14 and preferably also with the cover 10, which allows axial immobilization of the CF filter cartridge inside the housing 2. The format of the frame 7 is furthermore non-circular to allow an anti-rotation effect, for example by forming a polygonal outline, possibly rectangular as the case illustrated in [Fig.3] and in [Fig.4A]. Example(s) of construction of filter elements

[0029] The filter 1 may have separation means distributed at least between the first media 5 of a first filter element 11 and the second media 6 provided in a second filter element 12, by bringing together these media 5, 6 in the filter cartridge CF which is capable of being mounted in one piece in the housing 2 and of being removed as a unit. More generally, the first filter element 11 and the second filter 12 may be designed separately before an assembly phase with the frame 7 to enable the filter cartridge CF to be produced, independently of the total number of layers or filtration media provided in the filter 1. As described below, a rim 24 of the frame 7 may form a fixing support, in particular a fixing support by gluing, common to the first filter element 5 and to the second filter element 6.In addition, the CF cartridge may, if necessary, have additional filtration layers added from the outside of the frame 7, in variant embodiments using at least one additional filtration element.

[0030] Each of the first media 5 and the second media 6 may be air-permeable and compact, possibly in the form of a filter block with several superimposed layers. The filtration layers may be superimposed, extending generally parallel to each other. At least one of the layers is of the cellulosic type. Additionally or alternatively, a layer may include an adsorption material, possibly carbon, for example in the form of activated carbon.

[0031] A first filtering component constituting the medium 5 is for example provided and a second filtering component constituting the medium 6 is also arranged in the filtration chamber delimited by the housing 2 of the device 1. The second filtering component is designed and arranged to allow the second medium 6 to separate molecules or finer particles which have been able to pass through the first separation stage formed by the first medium 5. In examples, the first stage makes it possible to separate in particular particles of millimetric or submillimetric size while the second medium (forming a second filtration stage integrated in the CF cartridge) makes it possible to separate target particles or molecules of submillimetric and / or submicrometric size.

[0032] The first medium 5 or the second medium 6 may include a carbonaceous material, for example activated carbon. In a non-limiting example, the activated carbon may represent more than half of the total weight of the second medium 6. More broadly, the device forming the air filter 1 may have one or more filtration layers, at least one of which has an adsorption effect on volatile chemical compounds.

[0033] In order to form a first filtration stage which separates solid particles coming from the external environment, the first filter element 11 may have a fiber-based media 5, for example including cellulose. Specific pollutants, for example having an oxidizing power with respect to elements of the target region where the purified air discharged through the outlet 4 is conveyed, may be separated (if necessary selectively separated) by a filter layer included in the media 6 of the second filter element 12. In exemplary embodiments, the second separation stage has a function of adsorbing molecules from the air flow.

[0034] In one embodiment, the media 6 brings together several filtration layers, for example at least three layers, one of which includes an adsorption compound distributed in the form of solid grains and having porosity. The adsorption compound is for example distributed, typically homogeneously, in an intermediate layer between two filtration layers making it possible to maintain the carbon grains. This compound may be an activated carbon.

[0035] In the housing 2, the filter cartridge CF may be configured to force 100% of the flow F passing through the inlet 3 to pass through all the filtration layers of the cartridge CF. In particular, the air flow through first passes through an external face (first face F1) of the first filter element 11, emerges from another opposite face 11a of this element 11 by joining an intermediate space 13 between the two filter elements 11, 12 which is located inside the frame 7, then passes through the second filter element 12. For this, each of the first filter element 11 and the second child filter element 12 may include a peripheral part allowing, each, to achieve a seal by a respective circumferential annular contact against the inside of the frame 7.

[0036] With reference to [Fig. 5], one can see for example a first filter element 11 which has a peripheral member 21, of annular format, configured to surround the filtration medium 5, including an axial end for connection to the frame 7. In non-limiting exemplary embodiments, the peripheral member 21 defines a rectangular wall P5 whose height can be substantially equal to or slightly greater than the height of the first medium 5, which can optionally be pleated with pleats parallel to each other. At least a part of this wall P5 can be covered from the outside by a portion of the frame 7, for example a rectangular lower portion which extends longitudinally downwards from the rim 24. Of course, the rectangular geometry can be replaced by a different geometry, for example with some opposite sides not parallel and / or having at least five sides. It is understood that the annular peripheral member 21 has a function of supporting the first filtration medium 5 which is connected to the peripheral member 21, preferably by being fixed to an inner face of the peripheral member 21, here on the wall P5.

[0037] Like the first filter element 11, the second filter element 12 has a function of supporting the second filtration medium 6 which is connected to a peripheral belt 22, preferably by being fixed to an inner face of this belt 22, on the wall P6. It can also have an external perimeter defined in a suitable manner, in dimension and geometric shape, to allow at least partial insertion into the frame 7, from above. The second filter element 12 can then remain entirely on one side of the rim 24, here above the rim 24 in the fixed state, in a preferred embodiment.

[0038] The belt 22, of annular format, is configured to surround the filtration medium 6, including an axial end for connection to the frame 7. In non-limiting exemplary embodiments, the peripheral belt 26 defines a wall P6 substantially of the same geometric format as the wall P5 with regard to its circumference. The wall P6 may be covered from the outside by the frame 7 while delimiting a passage section for the air which is close to or substantially identical to the passage section for the air delimited by the wall P5. The height of the wall P6, possibly greater than that of the wall P5 in certain options, may be substantially equal to or slightly greater than the height of the second media 6, which may be pleated with pleats parallel to each other.

[0039] The peripheral member 21 and the peripheral belt 22 each have a structure with an annular end projecting axially (parallel to the axis X once the filter elements 11, 12 are mounted on the frame 7) relative to the media 5, respectively to the media 6, carried on the inside, so as to protrude, each relative to a face delimiting the intermediate space 13. The fixing on the frame 7 can thus be carried out by such projecting ends, in particular by gluing, without interference of gluing on the media 5 or 6.

[0040] The peripheral parts 21 and 22 may each include a sheet of a material, for example a sheet of synthetic / plastic material shaped to have a rigid conformation. On this peripheral part 21, 22, a deposit of an adhesive or material, for example hot-melt and capable of being reactivated (hot), may be carried out before fixing the corresponding media 5, 6. A gluing operation on each media 5, 6, which is for example pleated, may thus be facilitated. More broadly, each peripheral part 21, 22 can allow: - to maintain the two pleated media in position during design stages of the CF cartridge, in particular during the fixings between the frame and the sealing elements H, 12; - to ensure / participate in a seal between the dirty part of the filter element 11 and respectively 12, located at the bottom, and the clean part of this element 11, 12; and - to ensure good filtration efficiency by limiting the passage of various types of particles between the upstream zone Z1, the interlayer space 13 and the downstream zone Z2. Example of a support frame

[0041] With reference to Figures 4A, 4B and 5, the frame 7 can be made in a single piece. The frame 7 can have an inner rim 24 including an annular portion 24a which is perforated, so that holes 07 form through passages between a top of the rim 24 and a bottom of the rim 24. This top includes a first surface SI, while the bottom includes a second surface S2 which can optionally be parallel to the first surface SI.

[0042] On the annular portion 24a which projects radially inwards from an inner face F7 of the frame 7, axial projections oriented in opposite directions are formed constituting p: - a first axial projection 24b, for example annular, making it possible to delimit, by forming an internal circumference with a lateral retention effect for the still fluid bonding material, a lower cavity 15, optionally with a substantially constant spacing between the internal face F7 and the first projection; and - a second axial projection 24c, for example annular and which can be produced as an upward extension which extends parallel and opposite the first axial projection 24b, making it possible to delimit an upper cavity 16, optionally with substantially constant spacing between the inner face F7 and the second projection.

[0043] Each of the cavities 15, 16 can receive a corresponding end of filter element 11, 12, so that, in the presence of a bonding material M: - a free edge of the peripheral member 21 is embedded in the bonding material and inserted into a corresponding cavity, for example the lower cavity 15; - a free edge of the peripheral belt 22 is embedded in the bonding material and inserted into a corresponding cavity, for example the upper cavity 16. It is understood that the bonding material M can attach and rest, in a solidified state, on the first surface SI and on the second surface S2, in particular on the bottom region of the respective cavities 15 and 16.

[0044] The second axial projection 24c can, for this upper cavity 16, form an inner circumference with a lateral retaining effect for the still fluid bonding material. In this way, the bonding material M can remain confined along the face F7. In alternative embodiments, a greater number of cavities may be used in the attachment of the two filter elements 11, 12 and / or the filling with bonding material M may be done via indirect access to a receiving cavity of one end of the filter element 11, 12.

[0045] More generally, it is provided that the frame 7 surrounds both the peripheral member 21 and the peripheral belt 22 while allowing, by receiving a layer of bonding material split to occupy two cavities 15, 16 which communicate with each other via the openings 07 before filling, a function of holding the first filtering element 11 and the second filtering element 12, in a superimposed configuration with predetermined spacing, corresponding to the intermediate space 13, between the respective filtration media 5 and 6 which are arranged face to face in the hollow of the frame 7.

[0046] In the illustrated example, the inner rim 24 includes a T-section profile, so as to delimit, with the inner face of the frame 7, the lower cavity 15 and the upper cavity 16. This allows a bonding material M to fill the upper and lower cavities 16, 15 by taking advantage of a flow of bonding material that is still fluid, while it is poured from only one side of the frame, along the face F7 of the frame 7. In certain cases, it is permissible to use a frame 7 having, on a given side relative to the rim 24, a side wall 70 which extends around the longitudinal axis X, which exceeds the depth of any of the cavities 15, 16. On the side opposite the side wall 70, the frame 7 may have a lower bottom end 7a, typically annular. The inner face F7 may be distributed on the side wall 70 and on the lower end which is typically shorter than the side wall 70. When pouring the bonding material M from one side, the side wall 70 may possibly have a guiding effect for the flow of this material, into the upper cavity 16, which induces the filling of the lower cavity 15 via the holes 07 of the perforated wall 24a.

[0047] On an outer face of the frame 7, a fixing member is optionally provided allowing a suspension effect of the CF cartridge on the housing 2. In the non-limiting cases illustrated in FIGS. 1, 3 and 5, such a fixing member is in the form of an annular projecting relief RS enveloped by a seal J10.

[0048] Whatever the design of the frame 7, by assembly of parts or manufactured (for example molded) in a single piece, the cartridge CF may include an external region of contact with an annular seal J10 capable of delimiting a periphery of the filtering part including the layers / media 5, 6. The filtering part corresponds for example to a product inserted and placed or fixed in a removable manner on an annular edge. In a multi-piece design, the rim 24 may possibly belong to a part added and fixed on the inside of the wall 70 (wall 70 possibly in one piece which can already include the projecting relief RS). The portion with a T-section is provided as portion E7 made in one piece with the rest of the frame 4 or as an added part. The J10 seal is based on an elastomer, for example EPDM. Deformable, it can have a U-shaped section, enclosing a rim or relief RS projecting radially outwards and extending around the circumference of the frame 7.

[0049] The removable attachment of the CF cartridge can be carried out on a frame or an annular rim formed in the housing component 14. The seal J10 can be in sealing contact on an inner circumference of the housing component 14, for example by pressing from above on a seat zone of the same general shape (for example rectangular) and the same dimensions as the seal J10 (see for example the non-limiting case of [Fig.l]). The circumferential external relief RS, provided on the frame 7, can allow the seal J10 to be held in position around the wall 70 by itself. For this, the seal can have a first covering portion 25 which covers the relief RS from below and a second covering portion 26 covering the relief RS from above. In options, a U-shaped seal profile can be adopted. On the frame 7, the external relief RS can have a first side located substantially at the same level as the rim 24, and other sides for which this external relief RS can extend higher than the rim 24, in particular at least so that the seal J10 can be lower, on the side of the outlet 4 of the housing, and extend higher opposite this outlet 4.

[0050] When the seal J10 includes a generally U-shaped cross-section, it can also have two sealing lips L1, L2 including: - a first annular lip L1 which connects from below to the first covering portion 25, projecting downwards and outwards to a free edge of the first lip; and - a second lip L2 which connects from above to the second covering portion 26, projecting upwards and outwards to a free edge of the second lip. These lips L1, L2 can facilitate reversible compression when the cover 10 comes to close by pressing the seal J10 already resting on the seat zone which can correspond to an internal shoulder or groove of the housing component 14, located around the opening 02.

[0051] The CF filter cartridge is removably mounted, optionally extending under the outlet 4 belonging to the cover 10. The distance of the inlet face Fl of the filter element 11 or similar lower face of the cartridge CF, relative to the bottom 2a, may be greater than or equal to the height of the inlet 3 when the latter is formed laterally on the component 14. Independently or in addition to this, the distance (typically a vertical distance) between the seating area for the seal J10 and the bottom 2a may be greater than the height of the CF cartridge as measured along the direction of the longitudinal axis X in the assembled state. A water collection / decantation area (water separated by this CF cartridge, in particular by the first filter element 11) may then be provided on the side of the bottom 2a. The large vertical distance from the bottom 2a may allow an air reserve to be available inside the housing component 14, directly under the CF filter cartridge. Filter Cartridge Assembly

[0052] The filter cartridge CF may have a filter panel format, the frame 7 forming a delimitation from the outside of this cartridge. This frame 7 may be arranged horizontally, extending substantially parallel to the bottom 2a, with a joint J10 which may optionally be horizontal or which may be inclined with an upward inclination directly from a hinge connection 8. The axis A defined by the hinge components 8a of the connection 8 may be substantially horizontal in the assembled state. Regardless of the type of housing 2 used, the cartridge CF may combine a number of filter elements including: - the first filter element 11 connected to the frame 7 by a fixing layer accessible from a so-called lower side, preventing, for example, the face 11a of the media 5 from extending elsewhere than opposite the lower opening of the frame 7; and - the second filter element 12 connected to the frame 7 by a fixing layer accessible from a so-called upper side, for example preventing the media 6 from extending laterally beyond the periphery of the frame 7.

[0053] After the design of the first element 11 and the second element 12 respectively, provision is made to fix one then the other of these elements 11, 12 to the frame 7 successively. In a method of assembling the cartridge CF, the frame 7 can be engaged on a holding tool which engages against the inner rim 24. This rim 24 can act as an axial stop on which a counter-support surface, provided in the tool, engages, which makes it possible to axially plug a cavity 15 or 16 (visible in [Fig.4B] in particular) for an anti-flow effect of the material M deposited in the form of still fluid glue.

[0054] In a non-limiting example providing for first fixing the second filter element 12, the counter-surface can be inserted under or into the hollow zone of the frame delimited by the wall 70, until it comes into contact with one of the projections 24b or 24c. The frame 7 is then oriented vertically. With reference to [Fig. 5], the method can provide for presenting the end 7a facing downwards initially, with the cavity 16 ready to receive a bonding material M poured from above. The counter-surface, underlying the rim 24, temporarily forms a bottom of a compartmentalized annular housing with: the cavity 15, the cavity 16 and the holes 07 arranged between these two cavities 15, 16.

[0055] The method comprises a step of depositing the bonding material, for example hot, still fluid, in order to successively fill each of the compartments of the annular housing, until the end of filling allows a sufficient layer thickness of bonding material M to be available in the two cavities 15 and 16. The bonding material M migrates into the lower part of the annular housing and towards the counter-surface (typically solid / non-perforated surface) through the holes 07 provided for this purpose. In some options, the bonding material M is hot-melt and deposited while still hot. In other options, the bonding material M can also be of the two-component type, with a hardener, or having any suitable composition allowing a fluid state to be temporarily obtained.

[0056] After this filling, the fixing of the second filter element 12 is then allowed by introducing one end of the peripheral belt 22 into the cavity 16, with the bonding material M for example distributed on each side of this end which is generally annular, after insertion. The end of the peripheral belt 22 can be selectively embedded in the contact zone ZC2 for bonding, in a second sub-layer of the material M running along the second surface S2, distal / opposite to the counter-surface. The media 6 can optionally remain spaced (axially separated) from the zone ZC2. During the first step of fixing the filter element, the counter-surface remains held in contact against the lower projection 24b or 24c, for example by being attached to the projection 24a when the first filter element 12 is fixed to the frame 7.

[0057] In order to then fix the first filter element 11, the frame 7 is separated / extracted from the tool and a turnover is carried out, for example at 180°, in order to proceed with the gluing of this filter element 11. Either the turnover is sufficiently rapid and can be carried out after the separation of the tool. Or the turnover can be carried out while maintaining the contact position between the counter-surface and the frame 7, before separating the tool by an upward movement of the latter. It is then understood that the end 7a is oriented upwards.

[0058] The first filter element 11, which may be the one intended to be the lower element in the filter cartridge CF in the mounted state in the housing 2, can then be placed on the glued side of the rim 24 of the frame 7 (side still available) with insertion of at least one projecting end provided on the peripheral member 21, so that this member 21 is at least partially introduced into the bonding material M due here to its insertion into the annular cavity 15 or comparable glued fixing zone allowing a seal to be created against the frame. With reference to [Fig.3], the contact zone ZC1 for bonding allows, selectively, to embed a part of the first filter element 11. The zone ZR for filling the holes 07 corresponds to a discontinuous sub-layer linked to both the sub-layer of zone ZC1 and the sub-layer of material M of zone ZC2.

[0059] After the two fixings, a CF filter cartridge as shown in [Fig.3] can be obtained. A mounting superimposing more filter elements is also permitted. According to a slightly different embodiment including three filter elements in the cartridge, it is possible to use a frame glued in this way and optionally at least one other frame forming the same type of interface. The peripheral part of a filter element interposed between two other filter elements can then be arranged protruding on either side of its media to facilitate a connection from above and from below, respectively on an upper frame and on a lower frame. Example of cover

[0060] The opening 02 of the housing component 14 may constitute the only access by which the filter cartridge CF is mounted in the housing component 14. The cover 10 may have a domed shape. The articulation of the cover 10 is carried out selectively on one side of the component 14, for example a substantially rectilinear side, which makes it possible to border the opening 02. In the non-limiting example of [Fig.l] or 2, the cover 10 is curved at least opposite the hinge connection 8. This type of arrangement makes it possible to integrate external components, tubes and / or tubing in an area both close to the hinge connection 8 and the inlet 3, which can then leave space for the opposite side of the cover 10, which requires a certain amount of clearance so that the cover 10 is raised sufficiently (without interference with other components), to uncover the opening 02 when the filter cartridge CF needs to be changed.

[0061] In the illustrated examples, the outlet 4 has a certain mobility due to its integration on the cover 10, at a distance from the hinged connection 8. At least one clip MV' which belongs to the second connection system may be provided on the side opposite the connection 8 forming the first attachment system. The second attachment system allows manual attachment, without tools in preferred options. The cover 10 includes a rim for attaching the clip 7, preferably with a delimitation between two guide edges. The seal 10 may be housed in such a rim region (outwardly projecting rim) adjacent to the opening 02, for example so as not to locally reduce the section for the passage of the CF cartridge. The outlet 4 for the purified air can be offset vertically (higher) relative to a junction J between the cover 10 and the component 14, which makes it possible to locate the clip MV' under the opening constituting the outlet 4 with accessibility to this clip MV' permitted due to the available external spacing provided for the movement of the cover 10 when it is hinged opposite the outlet 4.

[0062] Just as the housing component 14 may include a retaining seat for retaining a lower end of the clip MV', which here includes a semi-circular spring-action blade, the cover 10 may have a flange which is axially overlapped relative to the seal J10 of the CF cartridge.

[0063] It may be provided, as in the non-limiting case of FIGS. 1 and 2, in a phase of closing the cover 10, to distribute the locking means / elements MV, MV' over the periphery of the cover 10. It is optionally permitted to first fix the clip MV', just after lowering the cover 10 to form the annular junction J. After this first removable fixing, the operator can manipulate one or two additional locking elements MV' to ensure that the cover 10 is also tightened on two parallel sides of the housing component 10 which extend transversely relative to the hinge connection 8.

[0064] With reference in particular to Figures 1 and 2, the cover 10 is kept closed with the junction J which can extend along a plane, when each locking element MV, MV' is engaged, with the achievement of a locked state of the cover 10. Whatever the method of attachment precisely adopted, the attachment to the cover 10 can be carried out above the junction J, for example by using extensions or other attachment means MF of the component 14 which form a gripping edge in an area overlapped from the outside. With reference to [Fig.2], at least one attachment bracket is provided for example which forms such an extension of the housing component 14. This type of arrangement makes it possible to multiply the points of traction / clamping contact on the component 14.

[0065] As seen in [Fig. 2], in a region sufficiently close to the junction edge opposite the hinge connection 8 (edge ​​overlapped here by the clip MV'), the housing 2 may be provided with two fixing brackets or similar MF elements providing a grip. The brackets, rigid and in the shape of an inverted U, are each integral with the housing component 14. In embodiment options, one or more MV clips may be provided on the cover 10 in a spaced manner relative to a flange of the cover 10, being vertically separated from this flange. Each of these elements, carried for example in a domed portion of the cover 10, is a clip distal to the J junction, as opposed to the MV' clip overlapping the J junction.

[0066] Non-limiting examples of geometric / dimensional parameters

[0067] The inlet 3 may have an intermediate arrangement in height in the housing component 14 housing all or part of the media 5, 6 of the CF cartridge. The CF cartridge may have a generally parallelepiped format with a perimeter rectangular external shape of the support frame 7. An equally rectangular format of the peripheral member 21 and of the belt 22 may be provided to allow each media 5, 6 to be distributed in a superposition not exceeding the internal passage section delimited by the frame 7, optimizing the available filtration surface. In exemplary embodiments, the second filter element 12 may be slightly higher than the first filter element 11.

[0068] The junction J may extend in a plane inclined relative to a plane of the bottom 2a of the housing 2, for example with an angle of inclination greater than 5 or 10° and less than or equal to 30 or 35°. The seal J10 may follow the inclination of this junction J. The bottom or lower end of the cover 10 may be dimensioned as a flange which is inserted (partially or totally) into the interior volume of the component 14 in order to crush the seal J10. Thus, when locking a closed position of the cover 10, the clamping effect applied using the locking elements MV, MV' accentuates the insertion of the lower end of the cover 10 into a high peripheral region of the interior volume of the component 14, which makes it possible to crush the peripheral seal J10. This seal J10 may be seated on a collar, a shoulder or in a groove of the component 14.

[0069] In a non-limiting embodiment, the thickness of the filtration layer formed by the first medium 5 may be greater than 1.5 mm, optionally greater than or equal to 2 mm without exceeding 3 mm. The air permeability of such a filtration layer may be greater than the permeability obtained in the second medium 6, the first medium 5 possibly having a permeability lying in a range of approximately 20 to 45 cc / cm2 / sec. Air Filter Assembly

[0070] The housing component 2 with the associated cover 10 can be fixed from below to a mounting region provided in a vehicle. With reference to [Fig. 2], fixing tabs 102 can extend downwardly from the lower wall forming the bottom 2a to allow mounting from above. It is understood that the housing 2 can be mounted vertically or generally vertically in a vehicle, having a lower end (forming the bottom 2a) parallel to the extension of the filter element EF. Preferably, the housing 2 has an inlet 3 and an outlet 4 which are each remote from the bottom 2a defining a bottom of the filtration chamber.

[0071] The hinged cover 10, tilted into the open configuration, reveals the opening 02 which is then accessible from the top, on the side opposite the bottom 2a. The filter cartridge CF can then be kept suspended in the housing component 14 by resting, by the seal J10, on an internal shoulder formed by the side wall of the component 14, close to the opening 02. This makes it possible to provide a large air space under the filter element 11 constituting a first filtration stage in the filtration chamber.

[0072] The articulation of the cover 10 makes it possible to limit the number of clips or locking elements, for example by not exceeding three clips while having good clamping efficiency. The use of stirrups or similar fixing means MF can contribute to well distributing the clamping force while having a limited number of locking actions. After installing the CF cartridge and closing the cover 10, all that remains for the operator to do is to push back a few clips in order to obtain the locking of the housing 2.

[0073] For subsequent unlocking, gripping the ends of certain clips can be facilitated by a high position and possibly offset inwards as illustrated for example for a locking element MV in [Fig.2], compatible with a cluttered environment on at least one side of the housing 2. The neck forming the outlet 4 can also carry, by a sleeve visible at the top of [Fig.2], an air flow sensor such as a mass air flow meter (called MAF).

[0074] It should be obvious to those skilled in the art that the present invention allows embodiments in many other specific forms without departing from the scope of the invention as claimed. For example, although the use of an interposed space 13 to avoid contact between the media 5 and 6 has been chosen in the above, variants may provide (if necessary by configuring a portion of a movable or deformable filter element) to obtain contact between the filtration media 5, 6.

[0075] Also, although a cycle including certain steps has been described in connection with illustrated examples, this does not exclude the addition of other steps, in particular depending on the needs of the intended application. Furthermore, the support frame 7 has been illustrated with a rectangular perimeter but, of course, other polygonal shapes are also usable, to cooperate with a housing of corresponding format. Furthermore, the bonding zone may have some variations in the distribution of the material or in its final shape. The material M allowing the fixing may correspond to any suitable material flowing in a fluid manner before being able to reach a solid state at ordinary operating temperatures, in particular at room temperature.

Claims

Claims

1. Air filtration cartridge (CF) for an air filter (1) having a housing (2) including an inlet (3) for the admission of a flow of raw air and an outlet (4) for the evacuation of purified air, the cartridge (CF) comprising: - a first filter element (11); - a second filter element (12); - a common support frame (7) for supporting the first filter element (11) and the second filter element (12) by making them integral with each other, so that the second filter element (12) is superimposed on the first filter element (11) to allow at least one intermediate filtration layer to be formed in the second filter element between an outlet face (11a) of the first filter element and the outlet (4) of the housing (2) in a mounted state of the cartridge (CF);characterized in that the frame (7) extends annularly around a longitudinal axis (X) having an inner face (F7) from which a rim (24) covered with a bonding material (M) is formed, so that the rim (24) includes a first surface (SI) for receiving a bonding layer based on the material for the first filter element (11) and a second surface (S2) for receiving a bonding layer of the same material for the second filter element (12), the second surface (S2) being oriented opposite the first surface (SI), and in that the first receiving surface (SI) and the second receiving surface (S2) are provided, in the rim (24), on an annular portion of perforated wall (24a) allowing migration of said fluid material (M), under the effect of gravity from one to the other of the receiving surfaces (SI, S2), by filling holes (07) distributed in the annular portion of the openwork wall (24a).;

2. Cartridge according to claim 1, wherein the first filter element (11) has an annular peripheral support member (21) and a first filtration medium (5) which is connected to the peripheral member (21), preferably by being fixed to an inner face of the peripheral member (21); wherein the second filter element (12) has a belt (22) and a second filter medium (6) which is connected to the belt (22), preferably by being fixed to an inner face of the belt (22); and wherein the peripheral member (21) is embedded in a first sub-layer of the material running along the first surface, while the belt (22) is embedded in a second sub-layer of the material running along the second surface, the filling of said holes with material making it possible to constitute a discontinuous intermediate sub-layer directly connecting the first sub-layer to the second sub-layer.

3. Cartridge according to claim 1 or 2, wherein the rim (24) projects radially inwards and includes a T-section profile, so as to delimit, with the inner face of the frame (7), a lower cavity (15) and an upper cavity (16), whereby the bonding material (M) can fill the upper cavity (15) and the lower cavity (16) by a flow made from only one side of the frame.

4. Cartridge according to any one of the preceding claims, in which the holes (07) are made in the form of oblong perforations.

5. Cartridge according to any one of the preceding claims, in which the frame (7) has a circumferential external relief (RS), preferably projecting radially on the outside of the frame (7), the cartridge including an annular seal (J10) which comprises: - a first covering portion (25) of the relief (RS) from below; and - a second covering portion (26) of the relief (RS) from above.

6. A cartridge according to claim 5, wherein the seal (J10) includes a generally U-shaped cross-section, further comprising two sealing lips, including: - a first annular lip (L1) which connects from below to the first covering portion (25), projecting downwards and outwards to a free edge of the first lip; and - a second lip (L2) which connects from above to the second covering portion (26), projecting upwards and outwards to a free edge of the second lip.

7. Air filter, comprising a filtering part, a housing (2) delimiting a filtration chamber between a component (14) of the housing and a cover, the filtering part being removably mounted in the filtration chamber, resting from above on a seat area formed by an inner edge of the component (14) which includes a bottom (2a) of the housing, the filter being characterized in that the filtering part includes said filter cartridge according to any one of the preceding claims, the housing further having a cover (10) for closing an opening (02) of the component (14) through which at least the first filter element (11) of the filter cartridge (CF) is placed in said component, opposite the bottom (2a), and in which the component (14) of the housing includes said inlet (3) for the admission of raw air flow, the outlet (4) for the discharge of purified air being provided in the cover (10), so as to delimit in said filtration chamber a downstream zone (Z2), between the second filter element (12) superimposed on the first filter element and a top of the cover (10) located opposite the bottom (2a).

8. Air filter according to claim 7, in which the cover (10) is hinged on the component (14) by a hinge connection (8) and capable of being closed and locked in a position for closing the opening (02), which is a position in which locking means (MV, MV') maintain a clamping between the component (14) and the cover (10) with a crushing of a peripheral seal (J10) of the cartridge (CF) between a shoulder or groove of the component (14) and a lower end of the cover (10).

9. Method for assembling an air purification filter cartridge (CF) including two filter elements (11, 12), by using a rigid frame (7), comprising the steps essentially consisting of: - providing the frame (7) which extends annularly around a longitudinal axis (X) by having an inner face (F7) from which is formed a rim (24) accessible from two opposite axial ends of the frame (7), the rim (24) being formed in a portion of perforated transverse wall (24a) having passage holes or slots (07); - gluing the rim by depositing a bonding material, using a first opening provided in one of the two axial ends, by depositing at least one fluid dose of bonding material (M), so as to distribute a quantity of the bonding material, a part of which serves to obtain at room temperature a so-called upper solid layer along a top of the rim;- allow excess fluid bonding material from said quantity to flow into the holes or passage slots (07), in order to; allowing distributed gluing on the top and along a bottom of said rim (24), by limiting the downward flow of the gluing material (M) by a counter-surface of a tool arranged directly above the rim in an annular region underlying the rim, whereby the gluing material (M) can also form a so-called lower solid layer; - producing, using said bonding material (M), two fixings on said frame (7), by bringing each of the two filter elements (11, 12) into contact with a corresponding layer chosen respectively from the upper layer and the lower layer, obtaining a first annular seal (ZC1) frame (7) - first filter element (11) and a second annular seal (ZC2) frame (7) - second filter element (12).

10. An assembly method according to claim 9, wherein, between the two attachments, the frame (7) and the tool are spaced apart from each other, the counter surface of the tool remaining in contact with the lower layer in a still fluid state during a first attachment provided for attaching one of the first and second filter elements, a second attachment being provided after a turning of the frame (7) followed by a withdrawal of the tool, in order to attach the other of the first and second filter elements and thus obtain a superimposed configuration of the second filter element (12) and the first filter element (11) which are separated by the rim (24).

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