FR3110089A1 - Filter cartridge and protective mask including it - Google Patents

Abstract

Filter cartridge and protective mask comprising it crossed by the air flow to be filtered. Cartridge (1) characterized in that the casing (3) consists of two parts (5, 5') mechanically assembled, with the ability to separate, in that a first part (5) consists of a cylindrical receptacle in the shape of pot, in that the second part (5') consists of a perforated cap incorporating an assembly flange (6), in that the bottom (7) of the receptacle (5) consists of a perforated surface structure and in that the cover (5') comprises elastic means (8) configured to maintain under pressure the layer(s) (4) against the bottom (7) of the receptacle (5) when the latter is assembled with the cover (5'). Figure to be published with abstract: Fig.4A

Description

Filter cartridge and protective mask comprising it

The present invention relates to the field of personal protective equipment for persons, more particularly in relation to the risks of intoxication, contamination and/or infection by the respiratory tract, and relates to a filter cartridge for a respiratory protection mask or analogue, as well as a mask (or preferably half-mask) for respiratory protection with multiple uses and with a composite and modular structure.

Numerous individual facial protection devices are already known, providing one or more types of protection for the wearer (specific protection or combined protections).

In the context of respiratory protection devices with filtering properties of the mask or half-mask type, three varieties of products are generally distinguished: single-use disposable masks, one-piece masks for repeated use and composite or modular masks, with consumables. interchangeable filters.

While the first two varieties are obsolete after one use or a limited number of uses, the third can be worn a large number of times when the consumable or worn parts are replaced regularly and the remaining parts can be cleaned (preferably disinfected) and maintained. This third variety of mask also provides better protection because their sealing elements are often of better quality and their higher purchase cost is largely amortized over a long protection period.

Generally, such a reusable composite respiratory mask essentially comprises i) a main body in the form of a more or less rigid shell, configured to delimit a hollow volume at least around the nose and the mouth of a wearer, ii) a seal of flexible interface, added or formed on the peripheral edge of the shell, delimiting a passage for the nose and the mouth and configured to come into leaktight contact on the wearer's face and iii) at least one strap for keeping said mask in intimate contact on the wearer's face, the main body further comprising at least one, preferably at least two, opening(s) configured for receiving a filtration element.

These filtration elements in the form of cartridges or cassettes contain a filter medium adapted to the type of filtration (dust, gas, microbes, bacteria, viruses, etc.) to be carried out at the level of the air sucked in by the wearer and constitute the consumable elements. interchangeable parts of the mask and must be changed after a certain period of use. This results in a cost of using the mask which remains high, and in particular prohibitive for individuals, and contributes to the production of composite waste that is difficult to recycle.

In addition, the user has no means of personalizing the mask to adapt it to his particular needs or comfort, nor to reuse unpolluted components after use.

Moreover, in the known embodiments of masks, the assembly interfaces of the filtration elements have complex structures, are tedious to use, are complicated to manufacture and relatively fragile, since they are often made of thermoplastic material.

The present invention aims to overcome at least the main drawbacks above.

To this end, its main object is a filter cartridge for a respiratory protection mask, essentially composed of a housing containing at least one layer of a filtering medium arranged to be traversed by the flow of air to be filtered, if necessary. several superposed layers of the same or different filter media(s), cartridge characterized in that the casing consists of two parts mechanically assembled, with the ability to separate, in that a first part consists of a receptacle cylindrical in the shape of a pot, configured to receive said at least one layer of filtering medium, in that the second part consists of an openwork cover incorporating an assembly flange, in that the bottom of the receptacle consists of a perforated surface structure and in that the cover comprises elastic means configured to maintain under pressure the layer(s) against the bottom of the receptacle when the latter is assembled with the cover .

The invention will be better understood, thanks to the description below, which relates to preferred embodiments, given by way of non-limiting examples, and explained with reference to the appended diagrammatic drawings, in which:

, [Fig. 1B] and [Fig. 1C] represent in the form of elevational views respectively from above, below and from the side of a filter cartridge according to the invention;

is a perspective view of the cartridge shown in Figures 1;

, [Fig. 3B] and [Fig. 3C] show, in the form of exploded views and in different directions, a case of a cartridge according to FIGS. 1 and 2, the two constituent parts being disassembled;

and [Fig. 4B] are sectional views, according to different planes, of a cartridge according to FIGS. 1 and 2;

and [Fig. 5B] are cross-sectional views, in different directions, of the cap or cover part of the case of FIGS. 3;

is a sectional view of the receptacle or pot part of the housing of FIGS. 3;

is a perspective view of another embodiment of the receptacle portion of the cartridge case according to the invention;

and [Fig. 9] are perspective views, with and without straps, of a mask according to the invention, with and without filter cartridges;

is a partial sectional view, to a different scale, showing the mounting by hooking the seal on the base body of the mask of Figures 8 and 9, and,

is a perspective view of a ready-to-mount assembly intended to form a mask as shown in FIG.

Figures 1 to 7 illustrate, at least in part, a filter cartridge (1) for a mask (2) for respiratory protection.

This cartridge is essentially composed of a casing (3) containing at least one layer (4) of a filter medium arranged to be traversed by the flow of air to be filtered, where appropriate several superimposed layers of the same or different filter media(s).

In accordance with the invention, the box (3) consists of two parts (5, 5') mechanically assembled, with the ability to separate. A first part (5) consists of a cylindrical receptacle in the shape of a pot, configured to receive said at least one layer (4) of filter medium, and the second part (5') consists of a perforated cover integrating an assembly flange (6). In addition, the bottom (7) of the receptacle (5) consists of a perforated surface structure and the cover (5') comprises elastic means (8) configured to ensure maintenance under pressure of the layer(s) (4 ) against the bottom (7) of the receptacle (5) when the latter is assembled with the cover (5').

Thus, the invention provides a filter cartridge (1) whose housing is removable and reusable to form a new cartridge after replacement of the layer (4) used by a new layer (similar or not) and possibly cleaning and / or disinfection of two component parts of the case. In addition, the cylindrical pot and annular cover structures of the two constituent parts 5 and 5' guarantee a maximum passage section for the air sucked in, the only real obstacle to its circulation being the crossing of the filter medium. In addition, the presence of the elastic means (8) guarantees that the layer (4) is held in place against the perforated bottom (7) and allows the use of layers (4) of different thicknesses, possibly multiple superimposed.

In accordance with a very advantageous embodiment of the invention, the elastic means (8) consist of leaf springs extending into the receptacle (5) along the internal face of its side wall (10) and coming into bearing under elastic stress, by compression and/or shearing, directly or not, on said at least one filtering layer (4), so as to urge it in the direction of the bottom (7) when the two parts (5 and 5') of the housing (3) are mutually assembled.

Preferably, the leaf springs (8), advantageously at least two or preferentially at least three, each have a partially helical constitution, each extend over a fraction of a turn and are preferentially formed in one piece with the assembly flange (6).

This flange (6) advantageously has an annular shape, with an opening substantially of the same size as the opening of the pot (5) and on the edge of which it rests and comes to rest when the housing (3) is assembled (open passage important). This collar (6) can be extended by a cylindrical skirt (6'), located outside the pot (5) in the assembled state of the case (while the leaf springs extend inside).

Maintaining the filtering layer or layers (4) in close contact against the bottom (7) can be achieved in different ways.

Thus, according to a first embodiment (not shown), the elastic means (8) bear directly against the peripheral edge of the filtering layer(s) (4) of discoidal shape, where appropriate on a portion of their length or via end portions in the form of support tabs (8'), and pinches this edge of the layer or layers (4) by compression against a solid peripheral annular band (7' ) of the bottom (7).

According to an additional characteristic of the invention, which may or may not be implemented within the framework of the aforementioned first embodiment, it may advantageously be provided that the box (3) comprises a second perforated surface structure (9), in the form of a discoidal piece separate or forming an integral part of the cover (5'), said at least one layer (4) of filter medium being sandwiched (with at least a certain elastic compression) between the bottom (7) of the receptacle ( 5) and this second structure (9) when the casing (3) is assembled, these two perforated surface structures (7 and 9) advantageously having alveolar meshes, for example in honeycombs, preferably coincident or concordant.

In order to force the flow of air to cross the filter layer(s) (4), each of the two perforated surface structures (7 and 9) can be peripherally provided with a frame or an edge (7', 9' ) continuous (non-perforated and solid), the layer of filter medium (4) being pinched between these two frames or edges (7' or 9') when the box (3) is assembled, a rib (7'') possibly being present on at least one of said edges or frames. It is thus provides peripheral sealing

In accordance with a second preferred embodiment of the invention, emerging from Figures 1 to 5, the second perforated surface structure (9) is stressed under elastic pressure in the direction of the bottom (7) of the receptacle (5), when the latter is assembled with the cover (5'), this under the action of the elastic means (8).

The structure (9) may consist of a separate part placed in the receptacle (5), after positioning the layer(s) (4), the blades (8) then coming to rest on the frame (9') when the cover (5') is mounted, ensuring the sandwiching of (4) between (9) and (7). For example, support ends in the form of legs (8') of the blades (8) can come into engagement with portions of projecting edges (9''') of the frame (9').

According to a preferred constructive variant, however, the structure (9) is made in one piece with these means (8). Thus, the ends (8') of the slats (8) can be one-piece with the portions (9'') or directly with the frame (9').

As shown in Figures 2 to 7, and in order to allow easy assembly and disassembly of the housing (3), it is advantageously provided that the receptacle (5) and the cover (5 ') include complementary means (11, 11') configured to produce by mutual cooperation a mechanical assembly connection (or coupling) of the bayonet connection type. The receptacle (5) may for example comprise lugs (11) and the cover (5') may for example comprise a receiving groove (11'), or respective adapted groove portions, with access openings (11 '') for said lugs (11), angularly offset in rotation. The assembly and disassembly is then done by relative rotation of a fraction of a turn (for example ¼) between pot (5) and cover (5 ').

Advantageously, the connection between the receptacle (5) and the cover (5') is removably locked, if necessary automatically, at the end of the assembly operation, for example by at least one notch (18), a point hard or similar.

Where applicable, the circulation path followed by the lugs (11) in the groove (11') or the groove portions, between the access openings (11'') and their final positions corresponding to the assembly of the housing (3), may possibly cause progressive compression of the elastic means (8). Thus, the ears (11) can be inclined (see figure 7) and the (portions of) grooves (11') have a partially helical shape.

The groove or groove portions (11') is (are) made in the collar (6) and/or in the skirt (6') and cutouts in the latter can possibly make it possible to check the correct assembly.

In order to allow the cartridge (1) to be able to be mounted by simple fitting in an orifice of conjugate shape of a mask (2), it is favorably provided that the cylindrical receptacle (5) has a frustoconical external shape, the external face of its side wall (10) tapering towards the bottom (7), a bevel (10') possibly being present at the level of the outer edge edge of said bottom (7).

The invention also relates, as shown in Figures 8 to 11, to a mask (or semi-mask) for versatile respiratory protection (2), with a composite structure.

This mask (2) essentially comprises a main body (12) in the form of a rigid or semi-rigid shell, configured to delimit a hollow volume (13') at least around the nose and the mouth of a wearer, a gasket flexible interface (14), attached or formed on the peripheral edge (12') of the shell (12), delimiting a passage for the nose and the mouth and configured to come into leaktight contact on the face of the wearer (13), and at least one strap (15, 15') for keeping said mask (2) in intimate contact on the wearer's face, the main body (12) comprising at least one, preferably at least two, opening(s) (6 , 6 ′) configured (s) for receiving a filtration element.

This mask (2) is characterized in that the or each opening (16, 16') comprises a site (17) for mounting, by means of a removable assembly by simple interlocking, of a filtration element ( 1) separate and interchangeable, said or at least one of said filtration element(s) consisting of a filter cartridge (1) as described above, the housing (3) of which is advantageously made of a thermoplastic material, for example PETG, polypropylene or polycarbonate (component parts coming from injection molding or made by 3D printing, for example).

According to one characteristic of the invention, the or each assembly site (17) consists of a tubular endpiece or sleeve, extending projectingly outwards from the corresponding opening (16, 16') and presenting a internal frustoconical shape, flared outwards.

Although it may result from overmoulding, the interface seal (14) is preferably a separate seal, fixed by attachment under elastic tension on the main body (12) at its peripheral edge (12'), to constitute a seal of the latter.

Said seal (14) advantageously consists of an annular flexible band folded on itself inwards to form a double wall, the folded band portion (14'') being configured to come into contact with the wearer's face (13 ). Such a construction ensures an intimate waterproof application of the mask (available in several sizes) on faces of different shapes.

To allow easy assembly and disassembly, while ensuring a strong connection, provision may be made for the main body (12) to include along its peripheral edge (12') a groove (12'') and for the gasket to sealing (14) comprises a bead or a circumferential rib (14') configured to be anchored in the groove (12'') with a view to the attachment of said seal to said body, by deformation elastic under tension of said bead (14').

As indicated previously, the mask (1) has a composite constitution and consists for example of an assembly of components (1, 12, 14, 15, 15') of a ready-to-assemble assembly.

If necessary, a wireless communication circuit, for example of the Bluetooth or WIFI type, can be housed in a suitable compartment of the housing (3) of a cartridge (1), electrical power supply means, a microphone and at the at least one earphone being mounted in the same compartment or in other dedicated housings of the shell (12).

Preferably, the mask or semi-mask (2) according to the invention meets the FFP2 criteria of the NF EN149 standard, and may comprise, depending on the uses, layers (4) of filter media of various kinds, in particular filters of the type HEPA (H12, H13, H14) or surgical filters. With the exception of the single-use filter medium, the other components of the mask (2) as well as the cartridge cases (1) are reusable and retain their properties even after several cleaning/disinfection operations.

More precisely, the layer (4) can consist of one:

•Mechanical filter, HEPA type (EN-1822), filtering more than 99.5% of particles;

•Electrostatic filter, in polypropylene (NF EN-149), filtering more than 94% of particles;

• Multilayer complex of textiles, fabrics, nonwovens, etc.

Advantageously, the mask meets the following requirements: Total leakage towards the outside of the mask < 8% (it corresponds to the internal and external concentration ratio of the mask and can be measured according to standard NF EN149+A1); the penetration of the half-mask filter against particles is < 6% according to the test provided for by standard NF EN13274-7; the inspiratory resistance is <0.7mbar at 30L/min and is <2.4mbar at 95L/min; the expiratory resistance is < 3.0 mbar at 160L/min; the carbon dioxide content of the inhaled air (dead space) does not exceed an average of 1.0% (by volume).

Of course, the invention is not limited to the embodiments described and shown in the appended drawings. Modifications remain possible, in particular from the point of view of the constitution of the various elements or by substitution of technical equivalents, without thereby departing from the scope of protection of the invention.

Claims (16)

Filter cartridge (1) for respiratory protection mask (2), essentially composed of a casing (3) enclosing at least one layer (4) of a filter medium arranged to be traversed by the flow of air to be filtered, the where appropriate several superimposed layers of the same or different filter medium(s), cartridge (1) characterized in that the casing (3) consists of two parts (5, 5') assembled mechanically, with the separation, in that a first part (5) consists of a cylindrical receptacle in the shape of a pot, configured to receive said at least one layer (4) of filter medium, in that the second part (5') consists of a perforated cover incorporating an assembly flange (6), in that the bottom (7) of the receptacle (5) consists of a perforated surface structure and in that the cover (5') comprises elastic means (8) configured to ensure that the layer(s) (4) are maintained under pressure against the bottom (7) of the receptacle (5) when this d last is assembled with the cover (5’). Filtering cartridge according to claim 1, characterized in that the elastic means (8) consist of leaf springs extending in the receptacle (5) along the internal face of its lateral wall (10) and coming to rest under elastic, by compression and/or shearing, directly or indirectly, on said at least one filtering layer (4), so as to urge it in the direction of the bottom (7) when the two parts (5 and 5') of the housing (3 ) are mutually assembled Filter cartridge according to Claim 2, characterized in that the leaf springs (8), advantageously at least two or preferentially at least three, each have a partially helical structure, each extend over a fraction of a turn and are preferentially formed of one piece with the assembly flange (6). Filter cartridge according to any one of Claims 1 to 3, characterized in that the elastic means (8) bear directly on the peripheral edge of the filter layer(s) (4) of discoidal shape, where appropriate over a portion of their length or via end portions in the form of support tabs (8'), and pinches this edge of the layer or layers (4) by compression against a peripheral annular band solid (7') from the bottom (7). Filter cartridge according to any one of Claims 1 to 4, characterized in that the casing (3) comprises a second perforated surface structure (9), in the form of a discoidal piece which is separate from or forms an integral part of the cover (5' ), said at least one layer (4) of filter medium being sandwiched between the bottom (7) of the receptacle (5) and this second structure (9) when the housing (3) is assembled, these two perforated surface structures ( 7 and 9) advantageously having alveolar meshes, for example in honeycombs, preferably coincident. Filter cartridge according to Claim 5, characterized in that each of the two perforated surface structures (7 and 9) is peripherally provided with a continuous frame or edge (7', 9'), the layer of filter medium (4 ) being pinched between these two frames or edges (7' or 9') when the casing (3) is assembled, a rib (7''; 9'') possibly being present on at least one of said edges or frames. Filter cartridge according to Claim 5 or 6, characterized in that the second perforated surface structure (9) is urged under elastic pressure in the direction of the bottom (7) of the receptacle (5), when the latter is assembled with the cover (5' ), this advantageously under the action of the elastic means (8). Filter cartridge according to any one of Claims 5 to 7, characterized in that the second perforated surface structure (9) is made in one piece with the elastic means (8). Filtering cartridge according to any one of Claims 1 to 8, characterized in that the receptacle (5) and the cover (5') comprise complementary means (11, 11') configured to produce by mutual cooperation an assembly connection mechanism of the bayonet connection type, the receptacle (5) comprising for example lugs (11) and the cover (5') comprising for example a receiving groove (11'), or respective adapted groove portions, with openings access (11'') for said lugs (11), angularly offset in rotation. Filter cartridge according to Claim 9, characterized in that the connection between the receptacle (5) and the cover (5') is locked in a removable manner, if necessary automatically, at the end of the assembly operation, for example by least one notch (18), a hard point or the like, the circulation path followed by the lugs (11) in the groove (11') or the groove portions, between the access openings (11'') and their final assembly positions of the casing (3), possibly resulting in a progressive compression of the elastic means (8). Filter cartridge according to any one of Claims 1 to 10, characterized in that the receptacle (5) has a frustoconical external shape, the external face of its lateral wall (10) tapering towards the bottom (7), a bevel (10') possibly being present at the level of the outer edge edge of said bottom (7). Multi-purpose respiratory protection mask (2), with a composite structure, essentially comprising a main body (12) in the form of a rigid or semi-rigid shell, configured to delimit a hollow volume (13') at least around the nose and the mouth of a carrier (13), a flexible interface seal (14), attached or formed on the peripheral edge (12') of the shell (12), delimiting a passage for the nose and the mouth and configured to come into sealed contact on the wearer's face (13), and at least one strap (15, 15') for keeping said mask (2) in intimate contact on the wearer's face, the main body (12) comprising at least one, preferably at least two, opening(s) (6, 6') configured for receiving a filtration element, mask (2) characterized in that the or each opening (16, 16') comprises a site (17) for mounting, by means of a removable assembly by simple interlocking, a separate and interchangeable filtering element (1) able and in that said or at least one of said filtration element(s) consists of a filter cartridge (1) according to any one of claims 1 to 11, the housing (3) of which is advantageously made of a thermoplastic material. Mask according to Claim 12, characterized in that the or each assembly site (17) consists of a tubular endpiece or sleeve, extending projectingly outwards from the corresponding opening (16, 16') and having an internal face of frustoconical shape, flared towards the outside. Mask according to either of Claims 12 and 13, characterized in that the interface gasket (14) is a separate gasket, fixed by hooking under elastic tension to the main body (12) at the level of its peripheral edge (12 '), to form a seal for the latter, said gasket (14) advantageously consisting of an annular flexible strip folded on itself inwards to form a double wall, the folded strip portion (14 '' ) being configured to come into contact with the face of the wearer (13). Mask according to any one of Claims 12 to 14, characterized in that the main body (12) comprises along its peripheral edge (12') a groove (12'') and in that the sealing joint ( 14) comprises a bead or a circumferential rib (14') configured to become anchored in the groove (12'') with a view to the attachment of said gasket to said body, by elastic deformation under tension of said bead (14'). Mask according to any one of Claims 12 to 15, characterized in that it has a composite constitution and consists of an assembly of components (1, 12, 14, 15, 15') of a ready-to-assemble assembly.