Field of application

[0001] The present invention relates to a filter group for a fluid.

[0002] According to a preferred embodiment, the filter group is specifically suitable for performing air filtration operations.

[0003] According to a further preferred embodiment, the filter group is specifically suitable for performing water filtration operations.

[0004] The context to which the present invention pertains is that of filter assemblies, preferably, but not necessarily, in the automotive field. In the automotive field, it relates to those filter assemblies that are connectable, by means of specific channels and specific manifolds, to operating groups of a vehicle or to specific spaces of the vehicle, so as to filter the fluid and prevent said operating groups or said spaces from being reached by fluids containing undesired particles. In other technical fields, reference is made to those filter assemblies that are connectable to specific ducts in which the fluid flows, which, following filtration, reaches an environment and/or a fuel cell.

[0005] Such filter assemblies are required to be suitable for performing an effective and efficient filtration of the fluid, preferably, but not necessarily, occupying a space as small as possible and avoiding obstructing the outflow of the fluid towards the operating group or the desired space.

[0006] In light of the above, it has been noted how, in order to have an effective and efficient filtration, the other needs of the technical field were not met. Conversely, when the filter assemblies are created as compact as possible, they have filtering properties with low effectiveness and low efficiency, or they act as an obstacle to the outflow of the fluid. Solution of the invention

[0007] The need is thus strongly felt to provide a filter group suitable for solving such an issue.

[0008] Precisely, it is the object of the present invention to provide a filter group for a fluid that has an effective and efficient filtering capacity, utilizing the spaces in a highly innovative manner and without acting as an obstacle to the outflow of the fluid. Preferably, therefore, by achieving such object, the filter group of the present invention is housable in narrow spaces.

[0009] Such an object is achieved by the filter group claimed in claim 1. [ 00010 ] The claims dependent thereon show preferred embodiments involving further advantageous aspects . Description of the drawings

[ 00011 ] Further features and advantages of the invention will become apparent from the description provided below of preferred exemplary embodiments thereof , given by way of non-limiting example , with reference to the accompanying drawings , in which :

[ 00012 ] - Figures la, lb, 1c and Id show a diagram of a preferred embodiment of the filter group of the present invention, in a top perspective view with separate parts , a bottom perspective view with separate parts , a front view and a longitudinal sectional view, respectively;

[ 00013 ] - Figures 2a, 2b, 2c and 2d show a diagram of a preferred embodiment of the filter group of the present invention, in a top perspective view with separate parts , a bottom perspective view with separate parts , a front view and a longitudinal sectional view, respectively;

[ 00014 ] - Figures 3a, 3b, 3c and 3d show a diagram of a preferred embodiment of the filter group of the present invention, in a top perspective view with separate parts , a bottom perspective view with separate parts , a front view and a longitudinal sectional view, respectively;

[ 00015 ] - Figures 4a, 4b, 4c and 4d show a diagram of a preferred embodiment of the filter group of the present invention, in a top perspective view with separate parts , a bottom perspective view with separate parts , a front view and a longitudinal sectional view, respectively;

[ 00016 ] - Figures 5a, 5b, 5c and 5d show a diagram of a preferred embodiment of the filter group of the present invention, in a top perspective view with separate parts , a bottom perspective view with separate parts , a front view and a longitudinal sectional view, respectively;

[ 00017 ] - Figures 6a, 6b, 6c and 6d show a diagram of a preferred embodiment of the filter group of the present invention, in a top perspective view with separate parts , a bottom perspective view with separate parts , a front view and a longitudinal sectional view, respectively;

[ 00018 ] - Figures 7a, 7b, 7c and 7d show a diagram of a preferred embodiment of the filter group of the present invention, in a top perspective view with separate parts , a bottom perspective view with separate parts , a front view and a longitudinal sectional view, respectively;

[ 00019 ] - Figures 8a, 8b, 8c and 8d show a diagram of a preferred embodiment of the filter group of the present invention, in a top perspective view with separate parts , a bottom perspective view with separate parts , a front view and a longitudinal sectional view, respectively;

[ 00020 ] - Figures 9a and 9b show a diagram of a preferred embodiment of the filter group of the present invention, in a top perspective view with separate parts and a longitudinal sectional view, respectively;

[ 00021 ] - Figures 10a and 10b show a diagram of a preferred embodiment of the filter group of the present invention, in a top perspective view with separate parts and a longitudinal sectional view, respectively;

[ 00022 ] - Figure 11 shows a diagram of a pre ferred embodiment of the filter group of the present invention, in a top perspective view with separate parts ;

[ 00023 ] - Figures 12a, 12b, 12c and 12d depict further diagrammatic embodiments of the filter group of the present invention;

[ 00024 ] - Figures 13a, 13b, 13c, 13d, 13e and 13 f show even further diagrammatic embodiments of the filter group of the present invention;

[ 00025 ] - Figure 14 shows a detailed embodiment of a filter group of the present invention, according to a preferred embodiment ;

[ 00026 ] - Figure 15 depicts a detail of a further embodiment of the filter group of the present invention, according to a preferred embodiment ;

[ 00027 ] - Figures 16a and 16b depict further embodiments and some corresponding details of the filter group of the present invention, according to a preferred embodiment ; [00028] - Figures 17a, 17b and 17c depict further embodiments and some corresponding details of the filter group of the present invention, according to a preferred embodiment ;

[00029] - Figures 18a, 18b and 18c depict further embodiments and some corresponding details of the filter group of the present invention, according to a preferred embodiment ;

[00030] - Figures 19a, 19b, 19c, 19d and 19e depict further embodiments and some corresponding details of the filter group of the present invention, according to a preferred embodiment;

[00031] - Figures 20a, 20b, 20c, 20a' , 20b' , 20c' , 20d, 20d' , 20e, 20f and 20f' respectively depict some diagrams of some preferred embodiments of the filter group of the present invention, in a longitudinal sectional view, respectively .

Detailed description

[00032] In the accompanying Figures, reference numeral 1 indicates a filter group in accordance with the present invention .

[00033] Said filter group 1 is crossable under filtration by a fluid.

[00034] Preferably, said filter 1 is crossable under filtration by air. [00035] Preferably, said filter 1 is crossable under filtration by water.

[00036] According to the present invention, the filter group 1 comprises a filtration region R in which the filtration of the fluid, and therefore the separation from the fluid of undesired substances and/or particles, occurs .

[00037] The filtration region R extends in length between an inlet area IN through which the fluid to be filtered flows, and an outlet area OUT through which filtered fluid flows.

[00038] As shown in the diagrams and as widely described below, the filter group 1 of the present invention is suitable for being highly flexible in the design, construction, and manufacturing thereof, so as to allow the mutual positioning of the inlet area IN and outlet area OUT according to specific needs.

[00039] The filter group 1 extends along a longitudinal axis X-X, along a transverse axis Y-Y and along a vertical axis V-V.

[00040] In accordance with a preferred embodiment, the longitudinal axis X-X extends in a linear direction.

[00041] In accordance with a preferred embodiment, the longitudinal axis X-X extends in a curvilinear direction (as shown by way of example in Figure 11, Figure 12a and Figure 13e) .

[00042] In accordance with a preferred embodiment, the longitudinal axis X-X extends in a broken direction (as shown by way of example in Figure 12b and Figure 12d) .

[00043] In accordance with a preferred embodiment, the longitudinal axis X-X extends in a mixed manner, having linear segments and curvilinear segments (as shown by way of example in Figure 12c) .

[00044] According to a preferred embodiment, the transverse axis Y-Y is transverse to the longitudinal axis X-X. Preferably, the transverse axis Y-Y is orthogonal to the longitudina L axis X-X. [00045] In accordance with a preferred embodiment, the transverse axis Y-Y extends i: i a linear direction. [00046] In accordance with a preferred embodiment, the transverse axis Y-Y extends in a curvilinear direction (as shown by way of example in Figures 13a, 13b, 13c, 13d, 13e and 13f) .

[00047] In accordance with a preferred embodiment, the transverse axis Y-Y extends i: i a broken direction. [00048] In accordance with a preferred embodiment, the transverse axis Y-Y extends in a mixed manner, having linear segments and curviline ir segments. [00049] According to a preferred embodiment, the vertical axis V-V extends from the longitudinal axis X-X, transversely thereto. Preferably, it extends transversely to the longitudinal axis X-X and transversely to the transverse axis Y-Y. Preferably, the vertical axis V-V is orthogonal to an imaginary plane in which both the longitudinal axis X-X and the transverse axis Y-Y lie.

[00050] In accordance with a preferred embodiment, the vertical axis V-V extends in a linear direction.

[00051] In accordance with a preferred embodiment, the vertical axis V-V extends in a curvilinear direction.

[00052] In accordance with a preferred embodiment, the vertical axis V-V extends in a broken direction.

[00053] In accordance with a preferred embodiment, the vertical axis V-V extends in a mixed manner, having linear segments and curvilinear segments.

[00054] According to a series of preferred embodiments, the filter group 1 has such a shape as to extend in length along said longitudinal axis X-X and said transverse axis Y-Y, for example, by positioning the inlet area IN and the outlet area OUT at two opposite ends along the longitudinal axis X-X, or by positioning the inlet area IN at a longitudinal end and the outlet area OUT at a transverse end.

[00055] According to a further preferred embodiment, the filter group 1 comprising a central cavity C and the filtration region R extends about the central cavity C. In other words, in such an embodiment, the filter group 1 has a substantially tubular shape, having a substantially cylindrical or conical or f rustoconical shape (as shown by way of example in Figures 13a, 13b, 13c, 13d, 13e and 13f) .

[00056] In accordance with such a preferred embodiment, in a first embodiment, the longitudinal axis X-X extends parallel along the tubular extension of the filter group 1, while the transverse axis Y-Y extends in a substantially circumferential direction, and the vertical axis V-V extends in a radial direction. Preferably, the inlet area IN and the outlet area OUT are positioned at two axial ends along the longitudinal axis X-X: the filter group 1 operates as an "axial filter". In other words, in this embodiment, the inlet area IN and the outlet area OUT are positioned at two longitudinally opposite ends, i.e., mutually spaced apart along the longitudinal axis X-X. Such a first embodiment is shown as an example in Figure 13a.

[00057] In accordance with the aforesaid preferred embodiment, in a second embodiment, the longitudinal axis X-X extends substantially radially with respect to the tubular extension of the filter group 1, while the transverse axis Y-Y extends in a substantially circumferential direction and the vertical axis V-V extends parallel along the tubular extension of the filter group 1 . Preferably, the inlet area IN and the outlet area OUT are positioned at two radial ends along the longitudinal axis X-X, i . e . , at least one of the two areas corresponds to the central cavity C : the filter group 1 operates as a "radial filter" . Preferably, the outlet area OUT corresponds to the central cavity C, while the inlet area IN is radially spaced apart outside the tubular filter group 1 : the filter group 1 operates as an outer-inner radial filter . Such a second embodiment is shown as an example in figures 13b, 13c, 13d, 13e and 13 f .

[ 00058 ] According to a preferred embodiment , in accordance with the embodiment with a " radial" filter crossable by the fluid from the outside to the inside , the inner cavity C delimits a fluid passage having a variable passage section .

[ 00059 ] Preferably, the inner cavity C delimits a fluid passage with an increasing passage section along the axis of the cavity itsel f . Preferably, said cavity C is obtained by stacking filtering panels 3 and baf fle panels 4 of a di f ferent annular shape . Preferably, therefore , the circulation of fluid through the filter group 1 in the distal portions from the outlet area, in particular in the distal portions from the axial end of the filter group 1 facing the outlet area OUT, is facilitated, thus improving the distribution of the flow under filtration along the axis of the filter group 1.

[00060] In accordance with the present invention, the filter group 1 comprises: a filtering panel 3 crossable by the fluid under filtration in a direction substantially orthogonal to the extension thereof;

- a baffle panel 4 impermeable to fluid;

- an inlet chamber 5 defined between the filtering panel 3 and the baffle panel 4.

[00061] In accordance with the present invention, the filtering panel 3 extends with respect to an imaginary plane F crossable by the fluid under filtration in a direction substantially orthogonal to the imaginary plane F.

[00062] According to a preferred embodiment, the filtering panel 3 extends in a substantially planar manner .

[00063] According to a preferred embodiment, both the longitudinal axis X-X and the transverse axis Y-Y lie on said imaginary plane F, therefore the shape of the imaginary plane F (i.e., linear or curvilinear or serrated) is a function of the shape of the longitudinal axis X-X and the transverse axis Y-Y. [ 00064 ] Therefore , the filtering panel 3 is crossable under filtration by the fluid in the thickness thereof . Preferably, the filtering panel 3 is crossable under filtration by the fluid in a direction substantially parallel to the vertical axis V-V .

[ 00065 ] According to a preferred embodiment of the present invention, the inlet chamber 5 is open in a region proximal to the inlet area IN and is closed in a region proximal to the outlet area OUT .

[ 00066 ] Preferably, the inlet chamber 5 is thus open only and exclusively in a region proximal to the inlet area IN, while it is closed in a region proximal to the outlet area OUT so that the fluid is forced to cross the filtering panel 3 .

[ 00067 ] According to a preferred embodiment of the solution of the present invention, the coupling of the filtering panel 3 to the baf fle panel 4 is such as to define an inlet chamber 5 shaped so as to comprise a first inlet area I I corresponding to a first section substantially orthogonal to the imaginary plane F in a region proximal to the inlet area IN and a second inlet area 12 corresponding to a second section substantially orthogonal to the imaginary plane F in a region distal from the inlet area IN .

[ 00068 ] Preferably, the first inlet area I I is greater than the second inlet area 12.

[00069] Preferably, the inlet chamber 5 has a decreasing passage section with a monotonous course along the extension thereof.

[00070] In other words, the coupling of the filtering panel 3 to the baffle panel 4 is such as to define an inlet chamber 5 having a larger passage section close to the inlet area IN and a smaller passage section close to the outlet area OUT.

[00071] As shown in the accompanying tables, and amply described below, this is achieved by particular shapes of the baffle panel 4, for example, comprising specific portions with a tapered course or comprising a greater number of components suitable for allowing the flow of the fluid in a region proximal to the inlet area IN with respect to the number of components present in a region proximal to the outlet area OUT.

[00072] Such a particular preferred embodiment is such as to allow a better access of the fluid into the inlet chamber 5 and is such as to let the filtering panel 3 work as homogeneously as possible.

[00073] In accordance with a preferred embodiment, the filter group 1 comprises a pair of baffle panels 4 impermeable to the fluid, positioned at the two opposite faces of the filtering panel 3. [ 00074 ] Preferably, the first baf fle panel 4 and the filtering panel 3 define said inlet chamber 5.

[ 00075 ] Preferably, the filtering panel 3 and the second baf fle panel 4 define an outlet chamber open in a region proximal to the outlet area OUT and is closed in a region proximal to the inlet area IN .

[ 00076 ] According to a preferred embodiment , the filter group 1 comprises a pair of filtering panels 3 , wherein the baf fle panel 4 is positioned in the space between two filtering panels so that said inlet chamber 5 is defined between the first filtering panel 3 and the baf fle panel 4 , and so that an outlet chamber 6 is defined between the second filtering panel 3 and the baf f le panel 4 .

[ 00077 ] Preferably, also in such an embodiment , said outlet chamber 6 is open in a region proximal to the outlet area OUT and is closed in a region proximal to the inlet area IN .

[ 00078 ] According to a preferred embodiment , the coupling of the filtering panel 3 to the baffle panel 4 is such as to define an outlet chamber 6 shaped so as to comprise a first outlet area 01 corresponding to a first section substantially orthogonal to the imaginary plane F in a region proximal to the inlet area IN and a second outlet area 02 corresponding to a second section substantially orthogonal to the imaginary plane F in a region proximal to the outlet area OUT.

[00079] Preferably, the first outlet area 01 is smaller than the second outlet area 02.

[00080] Preferably, the outlet chamber 6 has an increasing passage section with a monotonous course along the extension thereof.

[00081] In other words, the coupling of the filtering panel 3 to the baffle panel 4 is such as to define an outlet chamber 6 having a smaller passage section close to the inlet area IN and a larger passage section close to the outlet area OUT.

[00082] As shown in the accompanying tables, and widely described below, this is achieved by particular shapes of the baffle panel 4, for example, comprising specific portions with a tapered course or comprising a greater number of components suitable for allowing the flow of the fluid in a region proximal to the outlet area OUT with respect to the number of components present in a region proximal to the inlet area IN.

[00083] Such a particular preferred embodiment is such as to improve the circulation of the filtered fluid exiting from the filtering panel 3, as well as such as to let said filtering panel 3 work as homogeneously as possible .

[00084] In accordance with certain embodiments, the outlet chamber 6 is complementary to the inlet chamber 5. [00085] In accordance with such a preferred embodiment, in a manner complementary to the inlet channels 500, described below, the baffle panel 4 delimits specific, complementary, outlet channels 600.

[00086] According to a preferred embodiment, the inlet area IN and the outlet area OUT are spatially positioned as a function of the shape or of the position of the baffle panel 4 that delimits the outlet chamber 6 (as diagrammatically exemplified in figures 10a and 10b) .

[00087] In accordance with a preferred embodiment of the present invention, the filter group 1 comprises a plurality of filtering panels 3 and a plurality of baffle panels 4 stacked parallel to the direction of the vertical axis V-V.

[00088] In accordance with a preferred embodiment, the filter group 1 comprises a plurality of filtering panels 3 and a plurality of baffle panels 4 stacked parallel to the direction of the vertical axis V-V so as to form a plurality of inlet chambers 5 and a plurality of outlet chambers 6 crossed in parallel by the working fluid.

[00089] According to a preferred embodiment, the inlet chambers 5 and the outlet chambers 6 have the same height .

[00090] According to a preferred embodiment, the filter group 1 comprises a plurality of inlet chambers 5 and a plurality of outlet chambers 6 having different heights. [00091] In accordance with a preferred embodiment, the filter group 1 comprises a plurality of filtering panels 3 and a plurality of baffle panels 4 stacked parallel to the direction of the vertical axis V-V so as to form a plurality of inlet chambers 5 and outlet chambers 6 arranged so as to form two filtering portions crossable in series by the working fluid. In particular, each filtering portion comprises a plurality of inlet chambers 5 and outlet chambers 6 crossed in parallel by the working fluid.

[00092] In other words, a plurality of filtering panels 3 and baffle panels 4 are preferably alternated along said vertical axis V-V so as to identify a multiplicity of inlet chambers 5 and outlet chambers 6.

[00093] The term "panel" in the present description means a component that mainly extends along two preferential directions.

[00094] In accordance with a preferred embodiment, the filtering panel 3 and the baffle panel 4 have the same substantially square shape. In this case, the filter group 1 resulting from the stacking of a plurality of filtering panels 3 and baffle panels 4 has a cubic shape. [00095] In accordance with a preferred embodiment, the filtering panel 3 and the baffle panel 4 have the same substantially rectangular shape. In this case, the filter group 1 resulting from the stacking of a plurality of filtering panels 3 and baffle panels 4 has a parallelepiped shape.

[00096] In accordance with a preferred embodiment, the filtering panel 3 and the baffle panel 4 have the same discoidal shape. In this case, the filter group 1 resulting from the stacking of a plurality of filtering panels 3 and baffle panels 4 has a cylindrical shape.

[00097] In accordance with a preferred embodiment, the filtering panel 3 is a sheet-like filtering medium made of a porous filtering material.

[00098] According to a preferred embodiment, the filtering panel 3 is a filtering medium made of non-woven fabric .

[00099] Preferably, the filtering panel 3 is made from a non-woven fabric comprising polyester and/or polypropylene and/or polyamide and/or polyacrylate and/or viscose and/or rayon fibers and/or any combination thereof .

[000100] Preferably, the filtering panel 3 is a depth filtering septum made in the form of a flat sheet.

[000101] In accordance with a preferred embodiment, the filtering panel 3 is made of a non-woven fabric having a permeability between 150 and 950 mm/s, preferably between 550 and 700 mm/s (measured at 200 Pa) .

[000102] Preferably, the filtering panel 3 is singlelayer .

[000103] According to a preferred embodiment, the filtering panel 3 has an ISO5011 filtering efficiency greater than 99% (ISO FINE) .

[000104] According to a preferred embodiment, the filtering panel 3 has a thickness between 0.5 and 3.5 millimeters (measured according to ASTM D5729 - 1997) , preferably the filtering panel 3 has a thickness between 1.5 millimeters and 2.8 millimeters.

[000105] According to a preferred embodiment of the present invention, the filtering panel 3 is of the multilayer type. Preferably, each layer extends with respect to the imaginary plane F being crossable by the fluid to be filtered in a direction substantially orthogonal to the imaginary plane F.

[000106] In accordance with a preferred embodiment, the filtering panel 3 comprises a first filtering layer of permeable non-woven fabric, with a permeability between 750 and 900 mm/s (at 200 Pa) , coupled to a second filtering layer of non-woven fabric with a lower permeability, between 150 and 200 mm/s (at 200 Pa) .

[000107] In accordance with a further preferred embodiment , the filtering panel 3 comprises a third filtering layer positioned between the two outer layers and having an intermediate permeability, between 250 and 300 mm/ s ( at 200 Pa ) .

[ 000108 ] In accordance with an even further pre ferred embodiment , the filtering panel 3 contains adsorbent substances therein, such as activated carbons and/or ion exchange resins and/or zeolites .

[ 000109 ] In accordance with the present invention, ion exchange resins include resins suitable for gas adsorption . Preferably, ion exchange resins are suitable for the adsorption of acid gases , for example sul fur dioxide , and/or for the adsorption of basic gases , for example ammonia .

[ 000110 ] Preferably, the filtering panel 3 is of the multi-layer type and comprises a filtering layer suitable for filtering particles and an adsorbent layer suitable for adsorbing gaseous contaminants . Preferably, the filtering layer is positioned upstream of the adsorbent layer with respect to the fluid crossing direction . Preferably, the adsorbent layer comprises a plurality of adsorbent substances such as activated carbons and ion exchange resins .

[ 000111 ] According to a preferred embodiment , the filtering panel 3 is of the multi-layer type and comprises a filtering layer suitable for filtering particles and a plurality of adsorbent layers comprising respective adsorbent elements , preferably activated carbons .

[ 000112 ] In accordance with the present invention, the filtering panel 3 is of the multi-layer type and comprises an adsorbent layer 310 and at least one particle filtration layer 320 .

[ 000113 ] It is the main purpose of the adsorbent layer 310 to carry out the adsorption of gaseous contaminants . The adsorbent layer 310 is a permeable layer, crossable by the filtration flow through the thickness thereof .

[ 000114 ] It is the main purpose of the particle filtration layer 320 to filter solid particles and unwanted substances from the air . Preferably, the features of the particle filtration layer 320 are those described above in the embodiments of the single-layer filtering panel 3 .

[ 000115 ] According to the present invention, the adsorbent layer 310 comprises at least one permeable containment layer 311 .

[ 000116 ] Preferably, the permeable containment layer 311 is a fibrous layer .

[ 000117 ] According to the present invention, the adsorbent layer 310 comprises at least one layer with activated carbons and/or ion exchange resins 312 speci fically created to perform the action of adsorption and retention of gaseous contaminants .

[ 000118 ] In accordance with a preferred embodiment , the adsorbent layer 310 comprises two permeable containment layers 311 arranged at the opposite faces of the layer with activated carbons and/or ion exchange resins 312 .

[ 000119 ] Preferably, the adsorbent layer 310 has a thickness between 0 . 25 mm and 4 mm (measured according to the TAPPI T411 standard) . Preferably, the adsorbent layer 310 has a thickness between 0 . 5 mm and 2 mm, preferably between 1 mm and 2 mm . The thickness values indicated above may comprise one or both of the permeable containment layers 311 described above .

[ 000120 ] Preferably, the adsorbent layer 310 comprises one or more layers with activated carbons in granular form, for example in spherical form, and/or in pellet form and/or in powder form .

[ 000121 ] Preferably, the adsorbent layer 310 comprises one or more layers with activated carbons and/or ion exchange resins both in granular form, for example in spherical form .

[ 000122 ] Preferably, the adsorbent layer 310 comprises one or more layers with activated carbons in the form of fibers . For example , said fibers form a non-woven fabric or a fabric . Preferably, the adsorbent layer 310 comprises activated carbons in the form of fibers associated with support fibers , for example of a synthetic nature .

[ 000123 ] Preferably, the adsorbent layer 310 comprises one or more layers of composite fibers comprising activated carbons . For example , said activated carbons are in the form of granules or powder associated with support fibers , or in the form of coating on support fibers .

[ 000124 ] Preferably, the adsorbent layer 310 comprises one or more layers with activated carbons in the form of foam, preferably an open cell foam .

[ 000125 ] Preferably, the adsorbent layer 310 comprises one or more layers with laminated activated carbons in the form of a flat and flexible sheet .

[ 000126 ] Preferably, the adsorbent layer 310 comprises one or more layers with activated carbons each having a weight between 100 g/m2 and 1200 g/m2 , preferably between 200 g/m2 and 800 g/m2 . The values indicated refer to the net amount of activated carbons present in the adsorbent layer 310 , regardless of the presence of other components .

[ 000127 ] Preferably, each adsorbent layer 310 comprises activated carbons in granular form with a weight between 200 g/m2 and 400 g/m2 and a thickness between 1 mm and 2 mm .

[ 000128 ] Preferably, the at least one permeable containment layer 311 is made of non-woven fabric .

[ 000129 ] In accordance with a preferred embodiment , the adsorbent layer 310 comprises at least one permeable containment layer 311 , preferably made of non-woven fabric, and a layer with activated carbons and/or ion exchange resins 312 .

[ 000130 ] Preferably, the layer with activated carbons and/or ion exchange resins 312 is embedded between the permeable containment layer 311 and the particle filtration layer 320 .

[ 000131 ] In other words , in accordance with the aforesaid preferred embodiment , the particle filtration layer 320 acts both as a filtering layer and as a permeable containment layer with activated carbons and/or ion exchange resins of the adsorbent layer 310 .

[ 000132 ] According to a preferred embodiment , the adsorbent layer 310 is positioned upstream of the particle filtration layer 320 . In other words , the adsorbent layer 310 is positioned upstream of the particle filtration layer 320 with respect to the direction of circulation of the fluid under filtration through the filtering panel 3 . Preferably, the permeable containment layer 311 has, or the permeable containment layers 311 have, a lower filtering efficiency with respect to the particle filtration layer 320.

[000133] Preferably, the permeable containment layer 311 has, or the permeable containment layers have, a filtering efficiency class lower with respect to that of the particle filtration layer 320 being both measured according to the EN 1822 standard.

[000134] According to this preferred embodiment, the adsorbent layer 320 also acts as a pre-filter to protect the particle filtration layer 320.

[000135] Preferably, the particle filtration layer 320 is a filter with a high filtering efficiency. Preferably, the particle filtration layer 320 has an ISO5011 filtering efficiency greater than 99% (ISO FINE) .

[000136] Preferably, the particle filtration layer 320 has a filtering efficiency equal to or greater than category E10, measured according to the EN 1822 standard. [000137] Preferably, the particle filtration layer 320 has a filtering efficiency equal to or greater than category H13, measured according to the EN 1822 standard. Preferably, the particle filtration layer 320 is a filter of the HEPA type.

[000138] Preferably, the particle filtration layer 320 is a filter of the ULPA type. [000139] Preferably, the particle filtration layer 320 is a filter of the HEPA type with a thickness between 0.2 mm and 0.5 mm (measured according to the ISO 9073-2 standard) .

[000140] According to a preferred embodiment, the particle filtration layer 320 is positioned upstream of the adsorbent layer 310. In other words, the particle filtration layer 320 is positioned upstream of the adsorbent layer 310 with respect to the circulation direction of the fluid under filtration through the filtering panel 3. Preferably, the permeable containment layer 311 has, or the permeable containment layers 311 have, a greater filtering efficiency with respect to the particle filtration layer 320.

[000141] Preferably, the permeable containment layer 311 has, or the permeable containment layers have, a filtering efficiency class greater with respect to that of the particle filtration layer 320 being both measured according to the EN 1822 standard.

[000142] According to this embodiment, the particle filtration layer 320 is a filtering medium that works in thickness - similarly to what is described above for the single-layer filtering panel 3.

[000143] Preferably, the particle filtration layer 320 is used as a first permeable containment layer with activated carbons , on the side of the filtering panel that faces the inlet chamber 5 .

[ 000144 ] According to a preferred embodiment , the filtering panel 3 comprises a second particle filtration layer 320" positioned downstream of the adsorbent layer 310 and of the first particle filtration layer 320 with respect to the crossing direction of the fluid under filtration through the filtering panel 3 .

[ 000145 ] Preferably, the second particle filtration layer 320" has a greater filtering ef ficiency with respect to the first particle filtration layer 320 (measured according to the EN1822 or the ISO15011 standard) .

[ 000146 ] Preferably, the second particle filtration layer 320" has a filtering ef ficiency equal to or greater than category H13 , measured according to the EN 1822 standard .

[ 000147 ] Preferably, the second particle filtration layer 320" is a filter of the HEPA type .

[ 000148 ] Preferably, the second particle filtration layer 320" is a filter of the ULPA type .

[ 000149 ] Preferably, the second particle filtration layer 320" is used as a permeable containment layer 311 with activated carbons and/or ion exchange resins 312 .

[ 000150 ] Preferably, the second particle filtration layer 320" is a filter of the HEPA type and it is used as a permeable containment layer 311 for the layer with activated carbons and/or ion exchange resins 312 of the adsorbent layer 310 on the outlet side of the filtering panel 3 .

[ 000151 ] According to a preferred embodiment , the adsorbent layer 310 substantially extends along the entire length and along the entire width of the filtration region 520 . In practicing the invention, the adsorbent layer 310 substantially covers the entire surface of the filtering panel 3 crossable by the fluid under filtration .

[ 000152 ] According to a preferred embodiment , the adsorbent layer 310 partially extends in length and/or width along the filtration region 520 . In this embodiment , the adsorbent layer intercepts a portion of the fluid under filtration that crosses the filtering panel 3 . This means that the adsorbent layer 310 carries out the adsorption action thereof both on the fluid that crosses it as well as on the fluid that laps the surface thereof .

[ 000153 ] In accordance with a preferred embodiment , the configurations of the filter assemblies 1 having the multi-layer filtering panel 3 with adsorbent layer 310 fluidically positioned upstream of the particle filtration layer 320 are particularly suitable for being used in air conditioning systems .

[ 000154 ] The aforesaid embodiments with a multi-layer filtering panel 3 comprising at least one adsorbent layer 310 in accordance with what has been described above , are particularly suitable for filtering the air flowing in an air conditioning system or in a system supplying air to the cathode of a fuel cell .

[ 000155 ] In preferred embodiments for supplying air to the cathode of a fuel cell , at least one particle filtration layer 320 is fluidically positioned upstream of the adsorbent layer 310 with respect to the direction of circulation of the air flow under filtration through the filtering panel 3 .

[ 000156 ] In accordance with the above , advantageously, the baf fle panel 4 is not in direct contact with the layer with activated carbons and/or ion exchange resins 312 , but it is in contact with the at least one permeable containment layer 311 and/or with the particle filtration layer 320 .

[ 000157 ] In accordance with the embodiments described in the preceding two paragraphs , the baf fle panel 4 is not in direct contact with the layer with activated carbons and/or with ion exchange resins and/or zeolites , neither on the side facing the inlet chamber 5 , nor on the side facing the outlet chamber 6.

[000158] In accordance with a preferred embodiment, the filter group 1 comprises a plurality of filtering panels 3 of the multi-layer type and a plurality of baffle panels 4 stacked parallel to the direction of the vertical axis V-V so as to form a plurality of inlet chambers 5 and a plurality of outlet chambers 6 crossed in parallel by the working fluid.

[000159] Preferably, the filtering panels 3 are of the multi-layer type, comprising adsorbent layers with activated carbons and/or ion exchange resins of different types .

[000160] In accordance with a preferred embodiment, the baffle panel 4 is a sheet-like element made of a material belonging to the family of plastic materials.

[000161] In accordance with a preferred embodiment, the baffle panel 4 contains adsorbent substances therein, for example, activated carbons.

[000162] According to a preferred embodiment, the baffle panel 4 has a thickness of less than 1, preferably between 0.1 and 0.5 millimeters, preferably the baffle panel has a thickness of about 0.2 millimeters.

[000163] According to a preferred embodiment, the baffle panel 4 is worked by means of a thermoforming process.

[000164] In accordance with a preferred embodiment, the filtering panel 3 comprises an inlet filter edge 31 and an outlet filter edge 32.

[000165] Furthermore, the filtering panel 3 comprises side edges 34 that connect the inlet filter edge 31 to the outlet filter edge 32.

[000166] Preferably, the inlet filter edge 31 is proximal to, preferably faces, the inlet area IN, and the outlet filter edge 32 is proximal to, preferably faces, the outlet area OUT.

[000167] Similarly, the baffle panel 4 preferably comprises an inlet baffle edge 41 and an outlet baffle edge 42.

[000168] Furthermore, the baffle panel 4 comprises side baffle surfaces 44.

[000169] Preferably, the inlet baffle edge 41 is proximal to, preferably faces, the inlet area IN and the outlet baffle edge 42 is proximal to, preferably faces, the outlet area OUT.

[000170] In accordance with a preferred embodiment, said outlet baffle edge 42 sealingly engages the filtering panel 3.

[000171] Preferably, the outlet baffle edge 42 sealingly engages the outlet filter edge 32 closing the inlet chamber 5.

[000172] According to a preferred embodiment, the outlet baffle edge 42 comprises an outlet edge portion 420 comprising a housing cavity 421 in which the outlet filter edge 32 is housed.

[000173] In particular, the outlet filter edge 32 is preferably clamped into the housing cavity 421.

[000174] The refore, the outlet edge portion 420 preferably closes and blocks the flow of the fluid crossing the thickness of the filtering panel 3.

[000175] In accordance with other embodiments, the baffle panel 4 sealingly engages the filtering panel 3, with the purpose of defining the outlet chamber 6, even by means of the inlet baffle edge 41.

[000176] Preferably, the baffle panel 4 sealingly engages a filtering panel 3 with the outlet baffle edge 42 defining the inlet chamber 5, and sealingly engages the inlet baffle edge 41 of an adjacent filtering panel 3 defining an outlet chamber 6.

[000177] In accordance with a preferred embodiment, as shown by way of example in Figures 18a, 18b and 18c, the baffle panel 4 comprises, in a region proximal to the outlet area OUT, a portion shaped so as to have the sealing engagement on the first filtering panel 3 superimposed, along the vertical axis, to the sealing engagement on the second filtering panel 3, thus fluidically closing the inlet chamber 5. [000178] According to a preferred embodiment, the inlet baffle edge 41 engages the filtering panel 3 with an inlet edge portion 410 comprising an inlet housing cavity 411 in which the inlet filter edge 31 of said filtering panel is housed 3.

[000179] Preferably, similarly to the shaped portion described above, the baffle panel 4 comprises, in a region proximal to the inlet area INT, a portion shaped so as to have the sealing engagement on the first filtering panel 3 aligned along the vertical axis with the sealing engagement on the second filtering panel 3, thus fluidically closing the outlet chamber 6, but allowing the inlet into the inlet chamber 5 (as shown by way of example in Figures 17a, 17b and 17c) .

[000180] In accordance with a preferred embodiment, the inlet filter edge 31 is clamped into the inlet housing cavity 411.

[000181] The refore, the inlet edge portion 410 preferably closes and blocks the flow of the fluid crossing the thickness of the filtering panel 3.

[000182] In accordance with a preferred embodiment, the side baffle surfaces 44 sealingly engage the filtering panel 3.

[000183] In accordance with a preferred embodiment, the side baffle surfaces 44 sealingly engage the side edges

[000184] Preferably, the inlet chamber 5 is thus closed on three sides at the side baffle surfaces 44 and at the outlet baffle edge 42.

[000185] Preferably, the outlet chamber 6 is thus closed on three sides at the side baffle surfaces 44 and at the inlet baffle edge 41.

[000186] According to a preferred embodiment, said side baffle surfaces 44 extend in height substantially parallel to the vertical axis V-V.

[000187] According to a preferred embodiment, each side baffle surface 44 comprises a support foot 440 substantially parallel to the imaginary plane F, suitable for sealingly engaging the filtering panel 3.

[000188] Preferably, the inlet baffle edge 41 and/or the outlet baffle edge 42 comprise respective support steps substantially parallel to the imaginary plane F suitable for sealingly engaging the filtering panel 3.

[000189] In accordance with a preferred embodiment, the side baffle surfaces 44 comprise a protruding side portion 441 suitable for extending beyond the filtering panel 3 on the opposite side with respect to that in which the coupling of the baffle panel 4 to the filtering panel 3 defines the inlet chamber 5. Preferably, the protruding side portion 441 of a baffle panel 4 is suitable for engaging the subsequent baffle panel 4 allowing the stacking thereof in the vertical direction. Preferably, the protruding side portion 441 of a baffle panel 4 is suitable for engaging the subsequent baffle panel 4 so that the mutual engagement between two baffle panels 4 is sealed (as shown by way of example in Figure 15) .

[000190] According to a preferred embodiment, the baffle panel 4 is positioned in the space between two filtering panels 3, so as to sealingly engage both the first filtering panel 3 and the second filtering panel 3 with the side baffle surfaces 44.

[000191] Preferably, the side baffle surface 44 is shaped so as to have the sealing engagement on the first filtering panel 3 aligned, along the vertical axis V-V, with the sealing engagement on the second filtering panel 3. In other words, the side baffle surfaces 44 also have a preferred shape similar to that shown with reference to the outlet regions in Figures 18a, 18b and 18c.

[000192] In accordance with a preferred embodiment, the baffle panel 4 is shaped comprising a plurality of alternate walls 40 suitable for defining a plurality of inlet channels 500 in the inlet chamber 5.

[000193] Preferably, each inlet channel 500 comprises an inlet mouth 501 proximal to the inlet area IN and a filtration section 502 facing the filtering panel 3.

[000194] Thereby, the fluid is channeled at the inlet along each inlet channel 500, up to the filtration section 502 facing the filtering panel 3.

[000195] According to a preferred embodiment, each alternate wall 40 is connected to the next alternate wall in a top portion 401 and is connected to the previous alternate wall in a bottom portion 402.

[000196] Preferably, said top portions 401 and/or said bottom portions 402 are mutually joined to each other in an arcuate manner.

[000197] In some preferred embodiments, said top portions 401 and/or said bottom portions 402 comprise specific support planes.

[000198] In accordance with a preferred embodiment, the respective bottom portions 402 of the baffle panel 4 rest on the filtering panel 3.

[000199] In accordance with a preferred embodiment, the respective top portions 401 are engaged by a filtering panel 3.

[000200] Therefore, the baffle panel 4 also preferably acts as a reinforcement and support element for the filtering panels 3.

[000201] According to a preferred embodiment, the inlet channels 500 delimited by the baffle panel 4 have lengths which are different from one another, comprising primary inlet channels 500 which extend from the inlet area IN to a region proximal to the outlet area OUT.

[000202] According to a preferred embodiment, the inlet channels 500 delimited by the baffle panel 4 comprise auxiliary inlet channels 500 which extend from the inlet area IN to a region distal to the outlet area OUT.

[000203] According to a preferred embodiment, the baffle panel 4 comprises primary inlet channels 500 and auxiliary inlet channels 500.

[000204] According to a preferred embodiment, the inlet channels 500 delimited by the baffle panel 4 have a variable pitch along the transverse axis Y-Y (as exemplified in figure 12a, for example) .

[000205] Preferably, the pitch of the inlet channels 500 is a function of the very nature of the aforesaid channels .

[000206] Preferably, for example, the pitch of the inlet channels 500 is a function of the length of the inlet channels 500 having baffle panel portions with a greater number of channels in the region in which there are inlet channels 500 of a length shorter with respect to baffle panel portions where primary inlet channels 500 of a greater length are present.

[000207] According to a preferred embodiment, the baffle panel 4 transversely alternates primary inlet channels and auxiliary inlet channels (as shown by way of example in figure 13f) .

[000208] Such a preferred embodiment is particularly used on embodiments with filtering panels 3 having an extension with respect to longitudinal axes X-X or with respect to transverse axes Y-Y of a non-linear type, for example curvilinear.

[000209] In a completely similar but complementary manner, the same considerations described for the inlet channels 500 are present for the outlet channels 600 defined by the baffle panel 4: for example, where the inlet channels 500 have a course that decreases when decreasing in section, the outlet channels 600 expand when expanding the section thereof; for example, auxiliary outlet channels are at the location of primary inlet channels, and vice versa, primary outlet channels are at the location of auxiliary inlet channels.

[000210] According to a preferred embodiment, the inlet channels 500 have a constant section that is different from the constant section of the outlet channels 600. [000211] Preferably, the passage section of each inlet channel 500 is greater than the passage section of each outlet channel 600.

[000212] Preferably, in this embodiment, the distribution of the fluid flowing towards the filtering panel 3 is improved and the dust accumulation effect by each filtering panel 3 of the filter group 1 is maximized, also reducing the pressure drops.

[000213] According to the preferred embodiment, with a filter group 1 having a cylindrical shape and a radial flow, the filtering panel 3 is in the shape of a disc.

[000214] According to such an embodiment, the baffle panel 4 is in the shape of a disc.

[000215] Preferably, the filtering panel 3 and the baffle panel 4 are mutually engaged defining an inlet chamber 5 of an annular shape.

[000216] Preferably, the filtering panel 3 and the baffle panel 4 are mutually engaged to define an outlet chamber 6 of an annular shape.

[000217] Preferably, the baffle panel 4 has channels oriented in the radial direction. Preferably, the baffle panel 4 defines inlet channels 500 oriented in the radial direction. Preferably, the baffle panel 4 defines outlet channels 600 oriented in the radial direction (as shown in figures 13b to 13f) .

[000218] According to an alternative embodiment, the baffle panel 4 defines passage channels with a spiral geometry in the inlet chamber 5 and/or in the outlet chamber 6 (as shown in figure 13e) . [000219] In accordance with a preferred embodiment, the alternate walls 40 have an incident course, so as to delimit inlet channels 500 with a tapered course.

[000220] In accordance with a preferred embodiment, the alternate walls 40 have an incident course, so as to delimit outlet channels with a tapered course.

[000221] According to a preferred embodiment, the baffle panel 4 or the alternate walls 40 comprise baffle elements 409, so as to delimit inlet channels 500 with a tapered course.

[000222] Preferably, the baffle elements 409 are suitable for acting as a chute for the fluid towards the filtering panel 3.

[000223] In accordance with a still further embodiment, the filter group 1 comprises a container body 2 suitable for containing the filtration region R, containing the at least one filtering panel 3 and the at least one baffle panel 4.

[000224] Substantially, the container body has such a shape as to identify the inlet area IN and the outlet area OUT to fluidically connect them by means of the filtration region R, inside which the filtering panels 3 and the baffle panels are housed 4.

[000225] Furthermore, according to a preferred embodiment, the container body 2 comprises a perimeter gasket 20 which extends about the at least one filtering panel 3 and the at least one baffle panel 4, so as to define the inlet area IN.

[000226] In accordance with the accompanying diagrams and according to the corresponding specific needs of the designer, for example, according to the spaces present in the vehicle or in the installation space available in the filtering system, some features described and shown in a preferred embodiment are also present in other embodiments .

[000227] Preferably, in the diagrammatic figures from figure 1 to figure 13f, the baffle panels 4 are shown substantially planar; although, according to the needs, they have the wavy shape described so as to be suitable for defining the respective inlet channels 500 and the respective outlet channels 600 described above as shown in Figures 14 to 19e.

[000228] Further embodiments of the filter group are providable, in accordance with the present invention. For example, the features shown in the diagrams in Figures 20f and 20f' may be replicated in the diagrams in figures 20b, 20b' , 20c, 20c' , 20d, 20d' and 20e, respectively.

[000229] Innovatively, the filter group largely fulfills the purpose of the present invention, overcoming issues which are typical of the prior art. [000230] Advantageously, in fact, the filter group is suitable for filtering the fluid in a highly effective and efficient manner, not acting as an obstacle to the flow of the fluid, but rather favoring the motion thereof in a substantially main connection direction between the inlet area and the outlet area.

[000231] In fact, advantageously, the filter group has a wide inlet surface and a wide outlet surface while having however wide filtering surfaces.

[000232] Advantageously, the baffle panel favors the flow of the fluid at the inlet and favors the outflow of the fluid at the outlet. Advantageously, the baffle panel minimizes pressure drops imposed on the system in which it is installed.

[000233] Advantageously, the baffle panel distributes the flow rate of the fluid that hits the filtering panel, improving the utilization of the available filtering surface, increasing the time the gaseous molecules remain in the filtration region and increasing the capacity of adsorbing chemical contaminants by the filter group, increasing the range of possible applications available.

[000234] Advantageously, the baffle panel gives solidity to the filter group.

[000235] Advantageously, the baffle panel comprises an inlet edge that engage the filtering panel, improving the fluid dynamics of the filter group, in particular, reducing the pressure drops at the entrance to the inlet chamber .

[000236] Advantageously, the baffle panel comprises an outlet edge that engage the filtering panel, improving the fluid dynamics of the filter group, in particular, reducing the pressure drops at the exit of the outlet chamber .

[000237] Advantageously, the baffle panel comprises edge portions that engage the filtering panel, simplifying the separation between each inlet chamber and each outlet chamber .

[000238] Advantageously, the filter group is modular and is simply adaptable to the design needs by taking advantage of all the above advantages.

[000239] Advantageously, the filter group allows easily modulating the available filtering surface by selecting the number of filtering panels, baffle panels and/or by acting on the dimensions thereof, such as, for example, on the length thereof as well as on the composition of the adsorption layers.

[000240] Advantageously, at the design level, the behavior of the filtering panel is easily and faithfully determinable so as to produce effective and efficient filter assemblies. Advantageously, performance losses of the filtering panel, conventionally due to bending/def ormation operations, are avoided. In this solution, in fact, the filtering panel is used in the form of a flat sheet, similar to the experimental conditions in which it is tested and developed.

[000241] Advantageously, the filtering panels do not require multiple production operations, such as, for example, filtering panels comprising pleated paper filters .

[000242] Advantageously, the production costs of the filtering panels and filter group are highly low.

[000243] Advantageously, the filtering panels have a porous and permeable structure, thus managing to accumulate the contaminant in the thickness thereof and on the surface thereof.

[000244] Advantageously, the passage channels are formed on the baffle panel, keeping the structure of the filtering panel, on which no bending and/or deformation operations have to be performed, simple.

[000245] Advantageously, without needing to undergo folding operations, the filtering panels may have a multi-layer structure, for example, comprising at least one filtering layer and at least one adsorbent layer, thus allowing a multifunctional filtering structure with corresponding simplicity to be obtained, thus avoiding folding processes .

[ 000246 ] Advantageously, the filtering panels have a multi-layer structure with a substantially planar shape , managing in a highly flexible manner the number of filtering and/or adsorbent layers embedded in each filtering panel .

[ 000247 ] Advantageously, the filtering panels have a multi-layer structure with a substantially planar shape , managing the amount of adsorbent substance in a highly flexible manner .

[ 000248 ] Advantageously, the filtering panels are manufacturable by providing a high amount of adsorbent substance per surface unit , avoiding deformation processes (bending) and also taking advantage the structural support of fered by the presence of the baf fle panel and/or by the containment layers .

[ 000249 ] Advantageously, the filter group with at least one multi-layer filtering panel comprising an adsorbent layer coupled to a respective baf fle allows the adsorption of gaseous contaminants both by virtue of the circulation of the fluid through the thickness of the filtering panel ( flow through) as well as of the flow of the fluid on the surface of the filtering panel ( flow- by) . Advantageously, the adsorption capacity of the filter group is thus increased . [ 000250 ] Advantageously, the filter group with at least one multi-layer filtering panel comprising an adsorbent layer coupled to a respective baf fle increases the time the contaminant molecules remain in the inlet chamber and/or in the outlet chamber of the filter group, thus increasing the adsorption capacity of the filter group, given the same mass of adsorbent substance used .

[ 000251 ] Advantageously, the filter group with at least one multi-layer filtering panel comprising an adsorbent layer coupled to a respective baf fle allows increasing the probability of an encounter between a contaminant molecule and the active sites of the adsorbent substance , thus increasing the adsorption capacity and reducing the amount of mass necessary to ensure the accumulation of a predetermined amount of contaminant required by the speci fic application of the filter group . Advantageously, the multi-layer structure of the same adsorbent layer ampli fies the ef fectiveness and use thereof as well as its mutual engagement with the baf fle panels .

[ 000252 ] It is apparent that , in order to meet contingent needs , those ski lled in the art could make changes to the invention, all contained within the scope of protection as defined by the following claims .

List of reference signs :

[ 000253 ] 1 filter group

2 container body

20 perimeter gasket

3 filtering panel

31 inlet filter edge

32 outlet filter edge

34 filter side edge

310 adsorbent layer

311 permeable containment layer

312 layer with activated carbons and/or ion exchange resins

320 particle filtration layer

320" second particle filtration layer

4 baf fle panel

40 alternate walls

401 top portions

402 bottom portions

41 inlet baf fle edge

410 inlet edge portion

411 inlet housing cavity

42 outlet baf fle edge

420 outlet edge portion

421 outlet housing cavity

44 side baf fle surfaces

440 support foot 441 protruding side portion

49 baf fle element

5 inlet chamber

500 inlet channel

501 inlet mouth

502 filtration region

6 outlet chamber

600 outlet channels

X-X longitudinal axis

Y-Y transverse axis

V-V vertical axis

IN inlet area

OUT outlet area

R filtration region

F imaginary plane

Al first inlet area

A2 second inlet area

01 first outlet area

02 second outlet area

C central cavity