EMERGENCY OXYGEN DELIVERY ARRANGEMENT WITH OXYGEN STORAGE CARTRIDGE

Description

[0001] The present invention relates to a portable oxygen storage cartridge enabling a supply of oxygen (O 2 ) to a user, for a sufficient time, in a particular situation generating a harmful, hypoxic atmosphere and / or one laden with deleterious compounds, such as in the chemical or mining industries, which cartridge further comprises a bypass line containing an adsorbent and a saturation indicator, and an emergency oxygen distribution assembly comprising such a cartridge fluidly connected to a gas reservoir and to a respiratory interface, such as a respiratory mask.

[0002] The administration of gaseous O 2 is used to correct a hypoxemic situation, that is to say when the saturation of oxyhemoglobin in the blood is lower than a normal value, for example lower than 90%, in a human person, whatever their age, ie newborns, children, adolescents, adults, elderly people or others, suffering from a respiratory pathology such as Chronic Obstructive Pulmonary Disease (COPD), Acute Respiratory Distress Syndrome (ARDS) or other.

[0003] In this case, medical-grade oxygen is supplied to the "hypoxic" person either within a hospital or outside of a hospital, for example in a mobile emergency unit (SAMU, ambulances, etc.) or at the patient's home. Depending on the case, the oxygen supplied to the patient can come either from a gas pipeline (e.g., hospital network) or from a pressurized gas cylinder containing, for example, 400 to 1000 L of O 2 (gaseous vol.) compressed to 200 bar abs or more (measured at 1 atm).

[0004] There are, however, special situations in which O2 supplementation is necessary, even before a person shows signs of hypoxemia. This is particularly the case when a person is exposed to an "unbreathable" gaseous atmosphere, for example in the presence of toxic volatile chemical compounds within a room or industrial building or in the presence of a potentially hypoxic atmosphere, such as found in confined areas, such as mines, sewers or even tanks that have contained nitrogen (N2), for example.

[0005] In these particular situations, documents FR2201224 and FR2201227 (unpublished) propose using a portable oxygen storage cartridge comprising a closed cartridge body delimiting an internal volume receiving gaseous oxygen. The cartridge body is fluidically connected to a gas reservoir and to a respiratory interface, in particular a respiratory mask, such as a nasal or facial mask, so that gas exchanges can take place between these elements. Gas flow control valves are used to control the gas inlets and outlets from the internal volume. The internal volume contains a bed of adsorbent, for example zeolite, used to trap CO 2 molecules present in the gas exhaled by a user and which enter the internal volume of the cartridge after being recovered by the respiratory mask.Such an oxygen storage cartridge proves effective in providing an emergency supply of oxygen to a person faced with a particular situation generating a harmful hypoxic atmosphere (i.e. <21% O 2 ) and / or loaded with harmful compounds, such as fumes in the event of a fire or the like, to enable them to avoid breathing this harmful atmosphere by providing them with oxygen, for a period of several tens of minutes.

[0006] However, in practice, a problem has arisen related to the saturation of the adsorbent contained in the cartridge by CO 2 exhaled by the user. Indeed, as the cartridge is used, the adsorbent gradually becomes loaded with CO 2 exhaled by the user and it is currently impossible to know when the adsorbent is completely saturated since there is nothing to visually distinguish a saturated adsorbent from an unsaturated adsorbent, especially since this type of cartridge is formed from a totally opaque metal body.

[0007] However, this poses a real safety problem for the user because, when the adsorbent is saturated, the exhaled CO2 can no longer be retained by this adsorbent and will then gradually accumulate and concentrate in the gas reservoir, which can then cause gas poisoning of the user, i.e. hypoxia, if the user breathes this accumulated CO2 over a long period, i.e. several minutes or tens of minutes.

[0008] In this context, a problem is then to be able to simply know the degree or rate of saturation of such an oxygen storage cartridge in order to avoid the aforementioned problem, linked to the saturation of the adsorbent bed leading to non-retention of the exhaled CO 2 when the adsorbent is totally saturated. US2021121649A1 discloses the characteristics of the preamble of claim 1.

[0009] A solution of the invention then concerns a portable oxygen storage cartridge comprising: a cartridge body defining an internal volume for storing oxygen and comprising a first gas port and a second gas port in fluid communication with the internal volume, at least one gas flow control valve arranged in each of said first and second gas ports for controlling the flow of gas entering the internal volume and / or leaving the internal volume of the cartridge body, and at least one adsorbent bed containing at least a first adsorbent being arranged in the internal volume of the cartridge body, said first adsorbent having an adsorption capacity for gaseous CO 2 greater than an adsorption capacity for gaseous oxygen.

[0010] In addition, according to the invention, the portable oxygen storage cartridge further comprises at least one bypass line fluidically connecting at connection sites located upstream of each of said first and second gas ports so that a portion of the gas entering the internal volume through one or other of said first and second gas ports is diverted and circulates within said at least one bypass line. Said at least a portion of said at least one bypass line is formed of at least one transparent material and contains at least one second adsorbent material and at least one saturation indicator material.

[0011] Thus, part of the gas flow containing CO 2 can be diverted and circulate in the bypass line. The CO 2 is then gradually retained on the second adsorbent material, for example soda lime, which causes a variation in pH. This progressive variation in pH can then be "detected" by the saturation indicator material, such as ethyl violet, which will then gradually change color depending on the quantity of CO 2 trapped on the second adsorbent material, and therefore its saturation by the trapped CO 2. This variation in color reflecting the saturation rate of the second adsorbent material can be easily viewed in real time by the user through the transparent material constituting the bypass line so as to indicate to him when the second adsorbent material is completely saturated and therefore the cartridge is no longer operational and must be replaced.

[0012] Depending on the embodiment considered, the invention may comprise one or more of the following features: the transparent material is a polymer, preferably a thermoplastic. the polymer is a polycarbonate. the bypass line comprises an elongated tube. the elongated tube is cylindrical. the elongated tube has a diameter of between 0.5 and 10 mm, preferably of the order of 5 mm. said at least one first adsorbent comprises particles of at least one zeolite. said at least one second adsorbent material contained in the bypass line comprises soda lime. the soda lime comprises predominantly calcium hydroxide (CaOH) 2 , typically at least about 50 to 90% by weight of calcium hydroxide. the soda lime may further comprise sodium hydroxide (NaOH), typically less than 10% by weight of sodium hydroxide. the saturation indicator material is configured to gradually change color depending on its degree of saturation with CO 2 .the saturation indicator material is configured to change color depending on its degree of saturation by CO 2 by gradually changing from a whitish color to a violet color. the saturation indicator material comprises ethyl violet, also called ethyl violet. the saturation indicator material is in particulate form, preferably in the form of granules or the like. the saturation indicator material is substantially pH-sensitive, i.e. it reacts by changing color (i.e. tint or colorization) depending on the pH to which it is subjected. the second adsorbent, in particular soda lime, is in particulate form, preferably in the form of granules or the like. said at least one second adsorbent material and said at least one saturation indicator material are mixed with each other in the bypass line.the bypass line comprises a particulate mixture containing calcium hydroxide (CaOH) 2 and ethyl violet, and preferably lithium chloride (LiCl). the bypass line comprises granules comprising predominantly calcium hydroxide (CaOH) 2 , ie > 95% by weight approximately, lithium chloride (LiCl), ie <3% by weight approximately, and ethyl violet, ie approximately 1% by weight. the bypass line comprises at least 95% by weight approximately of calcium hydroxide (CaOH) 2 , less than 3% by weight approximately of lithium chloride (LiCl), and up to approximately 1% by weight of ethyl violet. the soda lime particles trap, i.e. retain, capture or the like, the CO 2 present in the gas stream, ie the gas exhaled by the user. the saturation indicator material reacts by gradually changing color as the CO2 is trapped (i.e. retained) by the soda lime particles, causing a variation in pH.the saturation indicator material reacts by gradually changing color from a whitish color to a violet color. the transparent material is a polymer, preferably a thermoplastic. the transparent material is a polycarbonate. the transparent material is chosen to allow the user to distinguish the color change of the saturation indicator material contained in the bypass line. the bypass line is connected to a first and a second conduit. said first and second conduits are connected to the cartridge body and in fluid communication with the internal volume of the cartridge body, via the first and second gas ports, respectively. said first and second conduits are connected to the cartridge body outside said cartridge body, i.e. upstream of the first and second gas ports.the first valve is arranged at the first gas port so as to control any passage of gas into or out of the internal volume via the first gas port. the second valve is arranged at the second gas port so as to control any passage of gas into or out of the internal volume via the second gas port. the bypass line is connected to the first and second conduits via a first and a second bypass conduit. the bypass line comprises screens, such as grids or the like, sandwiching the second adsorbent and the saturation indicator material. the bypass line comprises a graduated marking, i.e. graduations or the like. the cartridge body is tubular in shape. the cartridge body is closed at two opposite ends by a first and a second cover. the tubular body and the first and second covers delimit the internal volume used for storing oxygen.the gas flow control valves are arranged on said first and second covers, in particular a first gas flow control valve is arranged on the first cover and a second gas flow control valve is arranged on the second cover. the internal volume comprises a central chamber containing said at least one adsorbent bed of said at least one first adsorbent. the internal volume further comprises a first gas collection chamber and a second gas collection chamber, the central chamber being located between the first and second gas collection chambers, i.e. sandwiched between said first and second gas collection chambers. the cartridge body is hermetic. the cartridge body communicates fluidically with the outside via the first and second gas ports and through the gas flow control valves.the central chamber is separated from the first and second gas collection chambers by a first and a second sieve structure, respectively. the first and second sieve structures comprise grids or the like. the grids have a disc shape. the tubular body has an internal section and the sieve structures are arranged radially in the internal volume, ie perpendicular to the main axis (XX), so as to extend over the entire internal section of the tubular body. the tubular body is cylindrical. the internal volume of the cartridge is less than 1 L, typically of the order of 300 ml to 900 ml (water equiv.). the sieve structures are configured to maintain the first adsorbent bed containing said first adsorbent. said at least one first adsorbent comprises particles of at least one zeolite.the first adsorbent bed contains zeolite 13X or 5A particles having an oxygen adsorption capacity of at least 3 ml / g at 1 bar and 20°C. said at least one second adsorbent material contained in the bypass line comprises soda lime. the first adsorbent and the second adsorbent are configured or chosen so that a CO2 saturation front gradually moves therein as CO2 is retained therein. the sizing of the bypass line and the mass of the second adsorbent are configured and / or chosen so that the progression of the CO2 saturation front is identical in the first adsorbent, preferably a zeolite, and in the mixture of second adsorbent, such as soda lime, and saturation indicator material.Each control valve comprises a valve body, an annular sealing means, a movable element and an elastic means cooperating with each other to control the passage of gas through each control valve. Each control valve further comprises a cover piece for attaching to the valve body. The cover piece is screwed onto the valve body of each control valve. The cover piece has an external peripheral thread and the valve body of each control valve has an internal thread complementary to the external peripheral thread of the cover piece. Each control valve is movable between a rest position and an actuated or active position. In the rest position, no gas can enter or exit the cartridge through one and / or the other of the control valves.in the actuated or active position, a gas flow can be established through one and / or the other of the control valves so as to enter or exit the cartridge via one and / or the other of the control valves. the elastic means is arranged in the cover piece. the elastic means is sandwiched between the cover piece and the movable element. the elastic means is held by bosses arranged on the bottom of the cover piece and on the outer wall of the bottom of the movable element. the movable element comprises a peripheral collar. the elastic means pushes the movable element against the annular sealing means. the elastic means pushes the movable element against the annular sealing means so that the peripheral collar of the movable element comes into contact with the sealing means when a valve is in the rest position. the elastic means is a cylindrical coil spring. the annular sealing means is a flat O-ring.the valve body comprises an annular bottom having a central recess, the annular sealing means being arranged on said annular bottom, coaxially with said central recess. the movable element comprises a collar cooperating with the annular sealing means to ensure a fluid seal and prevent any circulation of gas through the central recess of the valve body of one and / or the other of the control valves, when one and / or the other of the control valves is / are in the rest position. in the active position, the collar of the movable element is not or no longer in contact with the annular sealing means so that the fluid seal is broken and a circulation of gas through the central recess of the valve body of one and / or the other of the control valves can be established. the valve body, the annular sealing means, the movable element, the elastic means and the cover part of each control valve are coaxial (axis XX).the valve body of each control valve has a tubular, typically cylindrical, shape. the valve body comprises an annular collar projecting radially outwards. the annular collar is arranged at a first end of the valve body. the valve body of each control valve internally comprises an annular base, preferably flat. the annular base of the valve body has a circular recess in its center. the annular base of the valve body forms an internal shoulder extending along the internal wall, i.e. the internal perimeter, of the valve body. the movable element is movable in axial translation (axis XX) in the valve body of each valve. the movable element has a cup shape. the movable element comprises one or more openings arranged in its peripheral wall. the cover piece has a cup shape. the cover piece comprises one or more openings arranged in its peripheral wall.the peripheral wall of the cover piece has a cylindrical shape. the movable element of each control valve comprises an external peripheral collar comprising one or more housings or recesses, such as notches. the cover piece comprises one or more axial guides, such as guide rails or the like, arranged axially along its internal wall. the recess or recesses carried by the external peripheral collar of the movable element are shaped to house the axial guides of the cover piece so that these axial guides can guide a translational movement of the movable part in the cover piece.

[0013] The invention further relates to an emergency oxygen delivery assembly comprising a portable oxygen storage cartridge for storing oxygen according to the invention, as described above, fluidically connected via said first and second gas ports of the cartridge to a gas reservoir and to a respiratory interface.

[0014] Preferably, the gas reservoir is flexible-shelled and / or the respiratory interface is a respiratory mask, particularly a nasal or face mask.

[0015] The invention will now be better understood thanks to the following detailed description, given for illustrative but non-limiting purposes, with reference to the appended figures among which: Fig. 1 is a schematic sectional view of an embodiment of an oxygen storage cartridge as described by FR2201224 or FR2201227, Fig. 2 is an exploded view of one of the valves integrated into the oxygen storage cartridge of Fig. 1 , Fig. 3 is an exploded view of part of the valve Fig. 2 , Fig. 4 is a side and sectional view of the valve of Fig. 2 , in its “resting” position, Fig. 5 is a sectional view of the valve of Fig. 2 , in its “activated” position, Fig. 6 is a side view of the valve Fig. 5 , Fig. 7 illustrates the oxygen storage cartridge of Fig. 1 , with its valves in the “operated” position, Fig. 8 schematizes the oxygen storage cartridge of Fig. 1 , connected to a tank (partially shown) and a mask (not shown), via gas lines, Fig. 9 diagrams an emergency oxygen distribution assembly including the oxygen storage cartridge of Fig. 1 , an oxygen tank and a breathing mask, Fig. 10 schematizes an embodiment of an improved oxygen storage cartridge according to the present invention, Fig. 11 is a simplified sectional view of the cartridge according to Fig. 10 , And Fig. 12 schematizes an embodiment of an emergency oxygen distribution assembly according to the invention, comprising the oxygen storage cartridge of Fig. 10 And Fig. 11 .

[0016] Fig. 1 is a schematic sectional view of an embodiment of a cartridge 1 for supplying emergency oxygen, as described by FR2201224 or FR2201227.

[0017] The cartridge 1 comprises a cartridge body or main body 13 closed at its two opposite ends 13A, 13B by a first cover 18 and a second cover 19, such as walls or the like closing the two ends 13A, 13B of the main body 13, so as to delimit an internal volume 12 used for storing the gas, namely here oxygen (O 2 ) in gaseous form.

[0018] Further provided are a first gas port 1-1 and a second gas port 1-2 which fluidly communicate with the internal volume 12. They are arranged on either side of the main body 13, i.e. the first gas port 1-1 is arranged in the first cover 18, while the second gas port 1-2 is arranged in the second cover 19. A first flow control valve 2 and a second flow control valve 3 are arranged in these first gas port 1-1 and second gas port 1-2, respectively, for controlling the gas inlets and outlets, i.e. the gas flows passing through the cartridge body 13, as explained below.

[0019] The main body 13 is formed here from an external tubular casing 11, preferably of cylindrical shape. The main body 13 is preferably made of metal, for example an aluminum alloy. The tubular casing 11 is elongated and extends along a main axis XX between the two ends 13A, 13B.

[0020] The first cover 18 and the second cover 19 carrying the gas orifices 1-1, 1-2, take the cylindrical body 13, typically the tubular casing 11, in a “sandwich” and are fixed there in a sealed manner, for example welded or crimped.

[0021] The first and second covers 18, 19 are preferably also made of metal, for example aluminum alloy.

[0022] The wall of the peripheral envelope 11 forming the main body 13 is thin, that is to say it has a thickness of the order of a few tenths of a millimeter.

[0023] Furthermore, the internal volume of cartridge 1 is around 300 ml to 900 ml (water equivalent).

[0024] One (or more) bed(s) 14 of one (or more) first particulate adsorbent 14-1, such as adsorbent beads for example, is arranged in the interior volume 12. In particular, the bed of first adsorbent 14-1 is sandwiched and held by / between two sieve structures 15, 16, more simply called 'sieves', that is to say that the first sieve 15 and the second sieve 16 are arranged on either side of the bed of adsorbent 14 so as to hold it in position in the internal volume 12 of the cartridge 1.

[0025] In other words, the sieve structures 15, 16 which are arranged radially in the internal volume 12, that is to say perpendicular to the main axis XX, and extend over the entire internal section of the main body 13 of cylindrical shape.

[0026] Preferably, the sieve structures 15, 16 make it possible to separate the internal volume 12 into several internal chambers or compartments, namely a central chamber 124 containing the first bed 14 of first adsorbent 14-1 located in the center of the cartridge 1, and a first and a second gas collection chamber 121, 122 located at the opposite ends 13A, 13B, that is to say between the central chamber 124 and the first and second covers 18, 19.

[0027] The sieves 15, 16 are for example formed from a mesh of metal fibers having a multitude of pores whose dimensions are smaller than the dimensions of the first adsorbent 14-1. According to other embodiments, the sieves 15, 16 may be in the form of foams comprising or formed from interconnected cells, or in the form of grids, for example metal grids, or the like.

[0028] In all cases, the sieves 15, 16 are sized to retain the adsorbent particles of the first bed 14 of first adsorbent 14-1. In other words, whatever the embodiment chosen, the bed 14 of first adsorbent 14 is "trapped" and held between the two sieves 15, 16, while the gas molecules are free to circulate through them.

[0029] In addition, the first adsorbent 14-1 is chosen to allow the adsorption of gas molecules, in particular oxygen molecules, due to tiny pores on its surface, i.e. pores of the order of one or a few nanometers (nm). Thus, it can be chosen from activated carbons, organometallic structures or MOFs for " Metal Organic Framework » or zeolites. However, preferably a zeolitic adsorbent is used, i.e. one or more zeolites, in the form of particles, such as granules, beads or the like, of one (or more) zeolite having a high adsorption capacity, i.e. at least 3 ml / g at 1 bar and 20°C, for oxygen, for example a zeolite 13X or 5A, for example the zeolite referenced Z10-ZZ marketed by the company Zeochem ®<.

[0030] As seen on Fig. 1 , the adsorbent bed 14 does not fill the entire internal volume 12 of the cartridge 1 but is arranged only in the central chamber 124 so that there are empty spaces at the two ends 13A, 13B of the internal volume 12 forming the first 121 and second 122 gas collection chambers.

[0031] The first gas collection chamber 121 is located between the first cover 18 carrying the first gas orifice 1-1 and the first sieve 15, and the second gas collection chamber 122 is located between the second cover 19 carrying the second gas orifice 1-2 and the second sieve 16. In other words, the two sieves 15, 16 separate the central chamber 124 containing the first adsorbent bed 14, from the first and second gas collection chambers 121, 122 which are located on either side of said central chamber 124, that is to say which sandwich it by being separated from it by the sieves 15, 16.

[0032] In addition, as visible on Fig. 1 , the gaseous oxygen cartridge 1 according to the invention has, as already said, also a first valve 2 and a second flow control valve 3 arranged at its two opposite ends 13A, 13B, typically carried by the covers 18, 19 and arranged at the first and second gas ports 1-1, 1-2. The first and second flow control valves 2, 3 serve to control the circulation of gas, i.e. the gas flows entering and leaving the internal volume 12 of the cartridge 1, via the first and second gas ports 1-1, 1-2 and through said first and second flow control valves 2, 3, as explained below and illustrated in Fig. 2 à Fig. 8 They are fixed in a sealed manner, for example welded or crimped, to the covers 18, 19, typically they pass through the covers 18, 19. The first and second flow control valves 2, 3 are preferably but not necessarily identical.

[0033] An embodiment of the architecture of these valves 2, 3 is detailed below in connection with Fig. 2 à Fig. 5 .

[0034] Fig. 2 is an exploded view of the first valve 2 equipping the oxygen storage cartridge 1 of the invention shown diagrammatically in Fig. 1 , knowing that the second valve 3 is strictly identical to it and works in the same way (valve 3 is therefore not detailed below).

[0035] More precisely, the first valve 2, like the second valve 3, is formed from an assembly of several elements 20-24 cooperating with each other, comprising a valve body 20, an annular sealing means 21, a movable element 22, an elastic means 23, such as a cylindrical spring with coils, and a cover piece 24, which are detailed below.

[0036] These elements 20-24 are arranged coaxially with respect to each other with respect to the axis XX of the valves 2, 3 and of the cartridge 1. Preferably, the elements 20-24 are metallic, for example made of an aluminum alloy; of course, other suitable materials may also be suitable. Corps de valve 20

[0037] The valve body 20 is generally cylindrical in shape. It has a length of the order of 8 to 16 mm measured between its two ends 20-1, 20-2, and an internal diameter (Di) typically between 18 and 30 mm.

[0038] The peripheral wall 201 of the valve body 20 carries, at its first end 20-1, an annular collar 202 projecting radially outwards.

[0039] In other words, the annular collar 202 is integral with the cylindrical external peripheral wall 201 of the valve body 20. They can be formed from a single piece or from several pieces assembled together.

[0040] The collar 202 forms an external shoulder, extending over the entire external periphery or perimeter of the valve body 20, making it possible to ensure a fluid seal between the valve body 20 and the cover 18 integrating the first valve 2 within the first orifice 1-1, for example by being fixed there by crimping, welding or any other suitable technique.

[0041] Furthermore, the valve body 20 also has an internal annular bottom 205, preferably flat. The annular bottom 205 has a circular recess 203 in its center and forms an internal shoulder, extending along the internal wall or internal perimeter of the valve body 20.

[0042] In addition, the valve body 20 has a thread 204 arranged on a portion 201a of its internal wall 201, from its second end 20-2. This thread 204 allows the connection by screwing of the support element 24, as explained below. Moyen d'étanchéité annulaire 21

[0043] The first valve 2 further comprises an annular sealing means 21, namely here a flat annular seal, e.g. an O-ring.

[0044] Preferably, it has a thickness of about 1 mm and an external diameter (De) slightly smaller than the internal diameter (Di) of the valve body 20, i.e. De <Di, de manière à pouvoir être inséré dans le corps de valve 20 et venir se positionner sur l'épaulement interne formé par le fond annulaire 205 du corps de valve 20.

[0045] The flat annular seal 21 comprises a front face 214 oriented towards the annular bottom 205 of the valve body 20 and a rear face 215 opposite the front face 214, that is to say oriented towards the collar 222 of the movable element 22, as detailed below. In addition, it also has a central passage 210 whose diameter is greater than that of the circular recess 203 of the valve body 20.

[0046] It can be made of different materials, in particular an elastomer, for example nitrile rubber, also called acrylonitrile butadiene rubber or NBR rubber for " Nitrile Butadiene Rubber » in English. Elément mobile 22

[0047] As seen on Fig. 2 And Fig. 3 , the movable element 22 is a structure having a general cup shape. More precisely, the movable element 22 comprises a front portion 221 of cylindrical shape which is open at its distal end 221b and closed, that is to say closed, at its proximal end 221a by a bottom wall 223, for example in the shape of a disc.

[0048] Preferably, the bottom wall 223 projects radially outwards, that is to say away from the external peripheral surface of the front portion 221 of cylindrical shape so as to form a collar 222, i.e. a ring structure, extending all around the cylindrical proximal end 221a of the front portion 221.

[0049] The cylindrical portion 221 has an external diameter smaller than the internal diameter of the circular recess 203 of the valve body 20, while the collar 222 has an external diameter greater than that of the recess 203 of the valve body 20 so that the movable element 22 is axially movable (axis XX) through the circular recess 203 of the valve body 20 and the central recess 210 of the flat annular seal 21 but cannot completely come out of it, given that it is retained there by the collar 222 when the latter abuts on the flat annular seal 21, which is itself arranged on the annular bottom 205 of the valve body 20, that is to say sandwiched between the annular bottom 205 of the valve body 20 and the collar 222 of the movable element 22.

[0050] The peripheral wall of the cylindrical front portion 221 is perforated, that is to say it has several lateral openings 227.

[0051] Furthermore, the outer face 224 of the bottom wall 223 comprises a central boss 225, that is to say a raised element, a surface protrusion or the like, typically of circular section. Here, the central boss 225 is of generally cylindrical shape and has a height of the order of 1 mm and a diameter which is less than the diameter of the collar 222, as visible in Fig. 2 , for example a diameter of the order of 4 to 8 mm. When the elastic means 23 is a cylindrical coil spring delimiting a cylindrical central passage 231, the diameter of the central boss 225 is slightly smaller than that of the central passage 231 of the spring so that the spring can be inserted on the central boss 225 in the manner of a sleeve. The central boss 225 cooperates with the elastic means 23, as explained below. Moyen élastique 23

[0052] The elastic means 23 is preferably a cylindrical coil spring positioned around the central boss 225, like a sleeve, and pressing on the outer face 224 of the bottom wall 223 in a substantially annular zone located immediately around the central boss 225 of the movable element 22. The elastic means 23, i.e. the spring, comprises a front end 232 coming into contact with the movable element 22 and a rear end 233 coming into contact with the cover part 24.

[0053] The internal diameter of the central passage 231 of the coil spring is therefore slightly greater than the diameter of the central boss 225, as already explained.

[0054] The elastic means 23 elastically pushes the movable element 22 towards the sealing means 21. Pièce-couvercle 24

[0055] The first valve 2 also comprises a tubular cover piece 24 delimiting an internal housing 240 for housing (at least) the elastic means 2 which is compressed and will then axially push back (XX) the movable element 22.

[0056] As seen on Fig. 2 And Fig. 3 , the cover piece 24 is formed of a main body 241 of cylindrical shape whose wall is pierced, that is to say crossed, by one or more lateral openings or windows 242. The main body 241 comprises, at its front end 24a, an opening 245 which communicates with the internal housing 240. At its rear end 24b, the main body is closed by a wall forming a bottom 243, preferably a flat bottom. In other words, the cover piece 24 has a general shape of a cup or similar with lateral openings 242.

[0057] The main body 241 of the cover part 24 also has, on its external surface, on the side of its front end 24a, a peripheral thread 244 which is complementary to the tapping 204 of the valve body 20 so that the cover part 24 can be fixed by screwing to said valve body 20 by taking in 'sandwich' the elastic means 23, the movable element 22 and the sealing means 21, as visible on Fig. 4 .

[0058] As seen on Fig. 2 And Fig. 4 , the sealing means, i.e. the flat seal 21, is inserted into the valve body 20. Its front face 214 comes into contact with the annular bottom 205 which forms an internal shoulder of the valve body 20.

[0059] The circular recess 203 located in the center of the annular bottom 205 of the valve body 20 is in fluid communication with the central passage 210 of the flat seal 21.

[0060] As illustrated in Fig. 4 , when the cover piece 24 is aimed at the valve body 20, it acts on the elastic means 23, namely the cylindrical coil spring, which is then compressed and then pushes, in turn, the movable element 22 towards the valve body 20. The movable element 22 then moves axially until its front portion 221 of cylindrical shape passes through the central passage 210 of the flat seal 21 and the circular recess 203 located in the center of the annular bottom 205 of the valve body 20 until it projects out of the valve body 20. The translational movement of the movable element 22 is stopped when the collar 222 comes into abutment against the rear face 215 of the flat seal 21.

[0061] The flat seal 21 is then sandwiched between the flat bottom 205 of the valve body 1 and the collar 222 of the moving part 22 which is pushed back by the cylindrical spring 23.

[0062] More precisely, the front end 232 of the cylindrical spring 23 comes into contact with the outer face 224 of the bottom wall 223 of the movable element 22 to push it elastically axially towards the flat seal 21, that is to say in the direction of the valve body 1.

[0063] The rear end 233 of the cylindrical spring 23 is in contact with the internal surface of the bottom wall 243 of the cover part 24, preferably it has just been placed around an internal boss 247 projecting at the center of the internal surface of the bottom wall 243 so as to mechanically hold the rear end 233 of the cylindrical spring 23, as explained above for the boss 225. The spring 23 is therefore held by and between the internal boss 247 of the cover part 24 and the external boss 225 of the moving part 22.

[0064] Furthermore, as illustrated in Fig. 3 , preferably, housings or recesses, such as notches 226, are arranged in the collar 222 of the moving part 22 and axial guides 246, i.e. guide rails or the like, are arranged axially along the internal wall of the cover part 24. The notches 226 are shaped to house said axial guides 246 so that these axial guides 246 can guide the translational movements of the moving part 22 in the cover part 24.

[0065] In other words, thanks to these notches 226 and axial guides 246, the moving part 22 can slide better in the internal volume of the cover part 24, in particular depending on the compression rate of the spring 23.

[0066] In the embodiment of Fig. 3 , we see 4 notches 226 arranged in the collar 222 of the moving part 22 cooperating with 4 corresponding axial guides 246 arranged axially along the internal wall of the cover part 24.

[0067] Fig. 4 is a side and sectional view of valve 2 of Fig. 2 , in its “rest” position, that is to say free from any external constraint.

[0068] In this case, the spring 23 is compressed (zone 234) between the collar 222 of the moving part 22 and the bottom of the cover part 24, and the moving part 22 then pushes the flat seal 21 against the flat bottom 205 of the valve body 20 so as to obtain a fluid seal between them.

[0069] In this “rest” position, no exchange of gas between the inside and the outside of the cartridge 1 occurs through the valves 2, 3 given that they are “closed” given that the orifice 203 of each valve body 20 is then closed by the bottom wall 223 of the moving part 22.

[0070] The cartridge 1 is then sealed and its internal volume 12 can then store oxygen under pressure. Thus, before use, the cartridge 1 can be filled with O 2 at a pressure of a few bars, for example of the order of a maximum of 10 bars absolute, which makes it possible to meet logistical constraints, in particular transport and storage. The introduction of the O 2 into the casing 11 can be done via a filling valve (not shown) arranged for example on the cover 18 or preferably, via one of the valves 2, 3, that is to say through one or other of the orifices 1-1, 1-2 which receive the first and second flow control valves 2, 3.

[0071] The presence of the first adsorbent 14-1 in the internal volume 12 of the cartridge 1 makes it possible to store a quantity of oxygen much greater than that which this gas container 1 could contain in the absence of adsorbent. Preferably, a zeolite having a high oxygen adsorption capacity is used as the first adsorbent 14-1, which therefore makes it possible to very significantly increase the gas storage capacity within the cartridge 1.

[0072] For example, at a pressure of 10 bar abs., a cartridge 1 of 660 ml of internal volume 12 can contain approximately 400 g of adsorbent 14-1 and, consequently, adsorb approximately 12 L of O 2 , while the interstitial space around the adsorbent particles 14-1 defines an "empty" volume in which O 2 molecules will also be compressed and stored, thus making it possible to increase the total capacity to approximately 15 L of O 2 (at atmospheric pressure). For comparison, in the absence of adsorbent 14-1, only approximately 6 L of O 2 could be stored there, i.e. 2.5 times less.

[0073] Fig. 5 et Fig. 6 represent a configuration (partially truncated views) where said first valve 2 is in the “actuated” position, that is to say when an external force is applied to the front part 221 of the moving part 22, for example when connecting a connector or the like, as explained below.

[0074] In this case, it can be seen that the moving part 22 no longer pushes the flat seal 21 against the flat bottom 205 of the valve body 20 and that the fluid seal is then broken, which allows gas to pass through said first valve 2.

[0075] In other words, the moving part 22 has undergone an axial translation towards the inside of the cartridge 1, that is to say in the direction of the cover part 24, which has the consequence of compressing the spring 23 towards the bottom of the cover part 24 while releasing the passage of gas between the flat seal 21 and the flat bottom 205 of the valve body 20.

[0076] The translation of the moving part 22 away from the valve body 20 causes a loss of contact between the front face of the collar 222 and the flat seal 21 and fluid communication is then created between the exterior and the interior of the cartridge 1, via the first control valve 2, in particular through the lateral openings 227 of the moving part 22 and the lateral openings 242 of the cover part 24. Of course, the second valve 3 operates on the same principle.

[0077] Fig. 7 shows the oxygen storage cartridge 1 with its two control valves 2, 3 in the “actuated” position, the structure and operation of the second control valve 3 being identical to those of the first control valve 2.

[0078] The control valves 2, 3 are in such an "actuated" position, when the oxygen storage cartridge of Fig. 1 has been connected by a user to external devices, for example to, on the one hand, a first gas conduit 4 and, on the other hand, a second gas conduit 6, as illustrated in Fig. 8 , thereby forming an emergency oxygen distribution assembly 50, as illustrated in Fig. 9 .

[0079] As seen in Fig. 8 , the first conduit 4 comprises a cylindrical casing 41 having a hollow internal conduit 42 or lumen, having the shape of a hollow cylinder.

[0080] The first conduit 4 is also fluidically connected to a deformable or flexible reservoir 5 (partially shown on Fig. 8 And Fig. 9 ) empty of gas, at the time of connection to the cartridge 1, but capable of being filled, i.e. inflated, with a given volume of gas after connection of the first conduit 4 to the cartridge 1. For example, the reservoir 5 may be configured to collect a volume of gas greater than or equal to the volume of gas contained in the interior volume 12 of the gas cartridge 1, i.e. O 2 . The reservoir 5 may be formed from a flexible polymer envelope. The first conduit 4 is fluidically connected, in a sealed manner, for example to the bottom 19 of the cartridge 1, for example by clipping, screwing or other means, carrying the second valve 3.

[0081] The internal conduit 42 of the first conduit 4 will then act on the moving part 22 of the control valve 3 to push it towards the inside of the cartridge 1 so that the second valve 3 is in the “actuated” position, with rupture of the seal at the flat seal of the control valve 3, as explained below.

[0082] A transfer of O2 then takes place from the internal volume 12 of the gas container 1 to the first conduit 4 then to the tank 5 which gradually increases in volume, i.e. fills with oxygen. Once the tank 5 is filled, a pressure equilibrium is established between the flexible tank 5 and the gas cartridge 1, the latter then being at atmospheric pressure (i.e. 1 atm).

[0083] By proceeding in the same way, the user can connect a second conduit 6 to the valve 2 equipping the cover 18, which, again, will push the moving part 22 to move the first valve 2 into its “actuated” position, as described above, and then establish a fluid connection between the internal conduit of the second conduit 6, the internal volume 12, the internal conduit 42 of the first conduit 4 and then, by extension, the reservoir 5.

[0084] The second conduit 6 can for example supply a respiratory interface 25, such as a respiratory mask, visible in Fig. 9 , which can be nasal or facial (i.e. naso-buccal), that is to say that the cartridge 1 is then ready for use by the user, who can inhale oxygen coming from the cartridge 1 and / or the reservoir 5.

[0085] Preferably, a respiratory interface 25 is chosen, such as a sealed respiratory mask, i.e. comprising sealing means around the perimeter of the opening through which the user breathes, i.e. the rear opening of the mask receiving the nose (nasal mask) or the nose and mouth of the user (face mask), for example sealing means of the flexible cushion type or the like coming into contact with the areas of the user's face surrounding his nose and / or his mouth, in order to create a fluid seal there.

[0086] Thus, during an inspiratory phase of the user, a part of the O 2 contained in the flexible reservoir 5, leaves the latter then passes successively into the internal conduit 42 of the first conduit 4, the internal volume 12 of the cartridge 1 through the adsorbent bed 14 and then leaves the internal volume 12 via the second conduit 6 and finally reaches the respiratory mask 25 worn by the user.

[0087] Conversely, during an expiratory phase of the user, a part of the inhaled O 2 (approx. 5% vol.) has been substituted by CO 2 and the gas exhaled by the user therefore contains CO 2 , water vapor and a high concentration of O 2 , i.e. more than 90% by volume. The exhaled gas will follow the opposite path to that followed by the inhaled oxygen, namely take the second conduit 6, cross the first valve 2 to then reach the internal volume 12 of the cartridge 1, and then pass successively through the adsorbent bed 14, then the second valve 3 and the first conduit 4 to finally reach the deformable reservoir 5.

[0088] A characteristic of the chosen adsorbent 14-1, such as zeolite particles, is that its adsorption capacity differs depending on the molecules considered. Thus, the adsorption capacity of O 2 is relatively low compared to the adsorption capacity of CO 2 or water vapor, typically 50 to 100 times greater. For a concentration of 5% CO 2 , i.e. 5 kPa in absolute pressure, the adsorption capacity of a zeolite, for example of the Zeochem Z10-ZZ or 5A type, thus has a volume storage capacity similar to the total volume of O 2 initially present in the gas cartridge 1, measured at 10 bar. This capacity is even greater for water vapor.

[0089] Therefore, when the gas exhaled by the user passes through the first adsorbent 14-1, the CO 2 molecules and the water vapor will be adsorbed so that the gas is freed from almost all of the CO 2 (and water vapor) that it contains, that is to say that it is almost pure oxygen. This CO 2 -free gaseous oxygen, which returns to the deformable reservoir 5, can then be inhaled again by the user, during a subsequent inspiratory phase.

[0090] As an indication, the metabolic oxygen consumption of an individual is at most 0.5 L / min, which implies that after 10 minutes of repeated inhalation / exhalation, the reservoir 5 contains approximately 5 L of O 2 less, under the aforementioned conditions, namely a pressure of 10 bar and a container volume of 660 ml. This makes it possible to meet the respiratory needs of a user for several tens of minutes.

[0091] Of course, several different adsorbents can be used, for example several successive beds of different adsorbents, namely zeolitics or others.

[0092] Such an emergency oxygen distribution assembly 50 comprising a portable oxygen storage cartridge 1 according to the invention connected, on the one hand, to a reservoir 5 and, on the other hand, to a respiratory interface 25, such as a mask, can be used to supply oxygen to a person, for a sufficient time, in a particular situation generating a harmful, hypoxic atmosphere and / or one laden with deleterious compounds.

[0093] The reservoir 5 and the respiratory interface 25 are mechanically connected to the oxygen storage cartridge 1 while ensuring fluid continuity between them, via suitable connection means, such as for example male / female connections by interlocking, by screwed or bayonet system, or other.

[0094] However, as explained above, such an emergency oxygen distribution assembly 50 does not make it easy to assess the saturation level of the adsorbent 14-1, capturing the CO 2 contained in the gas exhaled by the user, during its repeated expiratory phases. Indeed, as time goes by and the expiratory phases follow one another, the quantity of CO 2 retained by the first adsorbent, typically zeolite particles, increases progressively, that is to say that the CO 2 accumulates little by little in the first bed of adsorbent 14.

[0095] Potentially, this quantity of CO2 could exceed the adsorption capacity of said first adsorbent 14-1 and in fact all or part of the exhaled CO2 could circulate through the second valve 3, the first conduit 4 to finally reach the deformable reservoir 5 and accumulate there, then leading to a significant risk of intoxication and / or hypoxia for the user.

[0096] However, since the cartridge body 13 of the O 2 1 storage cartridge, which is typically formed of a tubular casing 11, typically cylindrical in shape, is generally made of metal, for example an aluminum alloy, and the same applies to the first 18 and second 19 covers which sandwich the cylindrical body 13 and are fixed therein in a sealed manner, the entire cartridge 1 is then opaque, thus preventing any visualization of the adsorbent 14 by the user. In any case, the first adsorbent 14-1, which is made of zeolite particles or the like, does not undergo any visually perceptible change, i.e. in shape, texture and / or color, when it gradually becomes saturated with CO 2 , and could therefore not allow the user to visually determine its saturation level.

[0097] From there, according to the invention, it is proposed to modify the cartridge 1 described above in order to reinforce the safety linked to the provision of the emergency O 2 distribution assembly 50, and therefore to allow a user to determine, easily and in (quasi) real time, the saturation level of the O 2 1 storage cartridge and to be able to anticipate its replacement before all or part of the expired CO 2 which becomes trapped on the first adsorbent 14-1, typically coming to be adsorbed on said first adsorbent, ends up in the reservoir 5, then posing a problem of poisoning or the like.

[0098] To do this, as illustrated in Fig. 10 à Fig. 12 , the invention provides an improved O 2 1 storage cartridge whose architecture and operation are generally identical to those of Fig. 1 à Fig. 9 , that is to say as described above, but implementing a bypass line 71, the architecture, role and operation of which are described below. Common or identical elements are not repeated since they are already detailed above; it is sufficient to refer to them.

[0099] More specifically, according to the invention, as illustrated in Fig. 10 à Fig. 12 , the O 2 1 storage cartridge is equipped with a bypass line 71, also called a bypass line, such as an elongated tube, which is fluidically connected to connection sites 42, 62 located upstream of the first and second gas orifices 1-1; 1-2, that is to say the ends of which are connected to the gas path, outside the cartridge 1, so that a portion of the gas, typically the CO 2 -rich gas exhaled by the user, entering the internal volume 12 of the cartridge 1, through one or other of the first and second gas orifices 1-1; 1-2, is diverted and circulates within this bypass line 71.

[0100] In other words, part of the gas circulating between the respiratory interface 25, cartridge 1 and the reservoir 5 (cf. Fig. 11 ), is derived and bypasses the O2 storage cartridge 1 by circulating within this bypass line 71 and no longer within the cartridge 1.

[0101] As visible in Fig. 10 à Fig. 12 , the bypass line 71 is preferably connected to connection sites 42, 62 located between the cartridge 1 and, on the one hand, the gas reservoir 5 and, on the other hand, the respiratory interface 25 of the emergency oxygen distribution assembly 50 according to the invention, that is to say sites located upstream of the first and second gas orifices 1-1; 1-2, therefore on either side of the cartridge 1.

[0102] Additionally, as detailed below, the bypass line 71 contains at least one second adsorbent material 75 and at least one saturation indicator material, preferably mixed with each other.

[0103] More precisely, Fig. 10 which is similar to the Fig. 7 , with the exception of the additional bypass line 71, represents the cartridge 1 according to the invention with its two control valves 2, 3 in the “actuated” position, after connection of the first conduit 4 to a deformable reservoir 5 and of the second conduit 6 to a respiratory interface 25, such as a nasal or facial mask, as illustrated in Fig. 12 .

[0104] As illustrated in Fig. 10 , the first conduit 4 comprises a first bypass conduit 43 which fluidically connects thereto at a first connection site 42 such that the lumen 41 of the first conduit 4 is in fluid communication with the lumen 44 of the first bypass conduit 43.

[0105] Similarly, the second conduit 6 comprises a second branch conduit 63 which fluidly connects thereto at a second connection site 62 such that the lumen 61 of the second conduit 6 is in fluid communication with the lumen 64 of the second branch conduit 63.

[0106] The first and second bypass conduits 43, 63 are respectively fluidically connected, by clipping or any other means, to the two opposite ends 72, 73 of the bypass line 71, namely here a long thin tube, also called a bypass tube, formed of one (or more) transparent material, such as a thermoplastic, for example polycarbonate. The internal volume 74 of said bypass tube 71 is filled with a second adsorbent 75, as described below.

[0107] The emergency oxygen delivery assembly 50 of the present invention is shown in simplified form in Fig. 11. It is understood that there is a fluidic relationship between the internal conduit or lumen 61 of the second conduit 6, the internal volume 12 of the O 2 1 storage cartridge, the internal conduit or lumen 41 of the first conduit 4, and the flexible reservoir 5 so that the gas can circulate between these elements of the reservoir 5 to the mask 25 connected to the second conduit 6, and vice versa.

[0108] The second conduit 6 has a branch (at 62) extended by the second bypass conduit 63 which communicates fluidically with a second end 73 of the bypass line 71 and, similarly, the first conduit 4 has a branch (at 42) extended by the first bypass conduit 43 which communicates fluidically with a first end 72 of the bypass line 71.

[0109] The bypass line 71 comprises the second adsorbent 75 which is held there between two sieves 76, 77 which sandwich it. The sieves 77 of the bypass line 71 may be similar or identical to the first and second sieves 15 and 16 arranged in the cartridge body 11, so as to allow gas circulation while preventing the second adsorbent 75 from moving in the bypass line 71.

[0110] There is a fluid relationship between the first and second conduits 4, 6 and the first and second bypass conduits 43, 63 such that a portion of the gas exhaled by the user can pass through the bypass line 71 by passing through the two screens 76, 77 and the bed of second adsorbent 75 sandwiched between them.

[0111] Thus, during an inspiratory phase of the user, a portion of the O2 contained in the flexible reservoir 5, leaves the latter then passes into the upstream portion 42a of the first conduit 4 to then be distributed between the downstream portion 42b of said conduit 4 and the first bypass conduit 43 of the first conduit 4.

[0112] A majority quantity of gas (i.e. > 80% of the volume) circulating in the downstream portion 42b of the first conduit 4 can then enter the interior volume 12 of the cartridge 1, pass through the first adsorbent bed 14, before exiting the interior volume 12 via the upstream portion 62a of the second conduit 62. At the same time, a minority quantity of gas (i.e. < 20% of the volume) circulating in the first bypass conduit 43 passes through the adsorbent 75 contained in the bypass line 71, i.e. transparent elongated tube, takes the second bypass conduit 63 of the second conduit 6 to finally open, at the branch 62, into the downstream portion 62b of the second conduit 6.

[0113] The gas flow circulating in the downstream portion 62b of the second conduit 6 is therefore the sum of the gas flows coming from the cartridge 1 and the bypass line 71.

[0114] This gas flow then passes through the lumen of the second conduit 6 to then arrive at the respiratory interface 25, like a respiratory mask worn by the user.

[0115] Conversely, during an expiratory phase of the user, the exhaled gas will follow the opposite path from the respiratory interface 25 to the reservoir 5 through the cartridge 1, on the one hand, and the bypass line 71, i.e. transparent elongated tube, on the other hand. This exhaled gas contains CO 2 , water vapor and a high concentration of O 2 , typically more than 90% by volume, given that a portion of the inhaled O 2 (approx. 5% vol.) has been substituted by CO 2 in the lungs of the user. The gas ultimately reaches the reservoir 5 where it resides until the next inhalation phase.

[0116] The proportion of gas passing through the first adsorbent 14 contained in the cartridge 1 compared to that passing through the second adsorbent 75 contained in the bypass line 71, in the inspiratory phase and in the expiratory phase, depends in particular on the pressure losses prevailing in the two paths taken by the gas flows, namely: the main gas path comprising in particular the cartridge 1 with the first and second sieves 15, 16 and the first adsorbent 14, the first and second valves 2, 3 and part of the conduits 4, 6. the bypass gas path comprising the bypass conduits 63, 43, the sieves 77, 76, the second absorbent 75 and the bypass line 71.

[0117] Thus, depending on the known characteristics of the main gas path (i.e. its resistance to the flow of a gas), it is possible to size by mathematical model or by experimentation, the bypass gas path, i.e. the quantity of second adsorbent 75, the sizing of the bypass conduits 63, 43 and the bypass line 71 in order to determine the exact quantity of gas passing through the bypass gas path. For example, it can be ensured that 10% of the gas passes through the bypass gas path and therefore 90% through the main gas path, or any other proportion.

[0118] Concerning the adsorbents used, when the first adsorbent 14 contained in the oxygen storage cartridge 1 is of the zeolitic type, for example the zeolite referenced Z10-ZZ marketed by the company Zeochem ®<, it is possible to choose as the second adsorbent 75 contained in the bypass line 71, soda lime (i.e. composed mainly of calcium hydroxide), preferably a mixture containing (at least) calcium hydroxide (CaOH) 2 and ethyl violet as a colored indicator.

[0119] An example of such an adsorbent / color indicator mixture is marketed under the name Litholyme ™< by Allied Healthcare Product Inc. This adsorbent / color indicator mixture is in the form of granules comprising mainly calcium hydroxide (CaOH) 2 , i.e. > 95% by weight approximately, lithium chloride (LiCl), i.e. <3% by weight approximately, and approximately 1% by weight of ethyl violet.

[0120] The calcium hydroxide (CaOH) 2 in the adsorbent / color indicator mixture reacts only with the CO 2 contained in the gas exhaled by the user to form calcium carbonate CaCO 3 .

[0121] The chemical reaction is irreversible and induces a change in the pH to which the colored indicator of the "ethyl violet" type or similar is sensitive and then turns from a whitish color, such as off-white, to a violet color, such as a bright purple. This change then makes it possible to visualize the state of each soda lime granule.

[0122] Thus, when a granule can no longer react with CO2, its color gradually changes from off-white to bright purple, which then allows the saturation level to be visualized. In other words, the colored indicator changes color depending on the pH to which it is subjected.

[0123] The CO2 adsorption capacity of this type of granule is around 130 ml of CO2 per g of product, i.e. 130 ml / g. For comparison, the first adsorbent 14 has a capacity of 65 ml / g, i.e. half as much.

[0124] Since CO2 is only present in the gas exhaled by the user, during its expiratory phases, only the gas circulating from the interface 25 to the reservoir 5 is likely to saturate the first and second adsorbents 14, 75. During the expiratory phases, the CO2 will be progressively captured by the first adsorbent 14, in particular via its upstream portion 14a located downstream of the first sieve 15 until it is saturated with CO2, that is to say until the saturation “front” which moves, reaches the downstream portion 14b located opposite the second sieve 16. The first adsorbent 14 then reaches complete saturation and can no longer adsorb CO2.

[0125] In the same way, the CO 2 present in the part of the gas flow circulating in the bypass line 71 will be captured by the second adsorbent 75, in particular its upstream portion 75a located downstream of the second sieve 77 until said portion 75a becomes saturated and the saturation “front” moves to the downstream portion 75b upstream of the first sieve 76. The second adsorbent 15 is then completely saturated and can no longer adsorb CO 2 .

[0126] According to the invention, the "saturation front" propagates progressively in the second adsorbent 75 contained in the bypass line 71, it can be visualized through the transparent material forming the wall of the bypass line 71, such as a transparent polycarbonate tube or the like, by the progressive appearance of a coloration following the saturation front, for example a violet coloration with the aforementioned adsorbent, i.e. the Litholyme ™ granules. Example

[0127] For a total volume of CO 2 V CO2 contained in the gas exhaled by the user propagating in the downstream portion 62b of the second conduit 6 and furthermore if “x” is the diversion rate of this volume in the second bypass conduit 63, and therefore (1-x) the complement circulating in the upstream portion 62a of the second conduit 6, then the respective maximum quantities of CO 2 which can be captured by the first and second adsorbents 14, 75 are as follows: x . V CO 2 = C 75 . M 75 et 1 − x . V CO 2 = C 14 . M 14

[0128] Or : C 75 represents the adsorption capacity (ml / g) of the second adsorbent 75, M 75 represents the mass (g) of the second adsorbent 75, C 14 represents the adsorption capacity (ml / g) of the first adsorbent 14 and M 14 represents the mass (g) of the first adsorbent 14.

[0129] It then follows that: M 75 = C 14 . M 14 C 75 . x 1 − x

[0130] Knowing the adsorption capacity of the two adsorbents 14, 75, and considering a mass of first adsorbent 14 of 500g, we then obtain: M 75 = 250 . x 1 − x

[0131] It then appears that the required mass of second adsorbent 75 depends on the diversion rate “x”, but that this mass also influences the diversion rate “x” because it causes resistance to flow.

[0132] Therefore, by using mathematical tools or by carrying out routine experimental tests, it is possible to determine the mass of second adsorbent (M 75 ) and the sizing of the different elements constituting the bypass gas path, that is to say in particular the bypass line 71, such as a bypass tube, the bypass conduits 43, 63, so that the preceding equation is verified.

[0133] In fact, the progression of the saturation fronts in the adsorbents 14, 75 is done in a ratiometric way. In other words, if we consider the saturation level as

[0134] being 0% when the first adsorbent 14 captures the CO 2 near the first sieve 15 and similarly, when the second adsorbent 75 captures the CO 2 near its second sieve 77, and 100% when the first adsorbent 14 captures the CO 2 near the second sieve 16 and therefore the second adsorbent 75 captures the CO 2 near its first sieve 76.

[0135] From then on, the second adsorbent 75 follows the same saturation level as the first adsorbent 14 as the user successively exhales, with the advantage of providing the user with visual information on the level of progression of the adsorption front, marked by the progressive appearance of a purple coloration of the second adsorbent 75.

[0136] Advantageously, a graduated marking, i.e. graduations or the like, can be provided, for example on the transparent tube forming the bypass line 71, making it possible to assess the saturation rate in a simpler and more quantifiable manner.

[0137] The emergency oxygen distribution assembly 50 according to the invention with O2 1 storage cartridge 1 provided with a visual indicator makes it possible to measure in real time the saturation rate of the first adsorbent 14 contained in the O2 1 storage cartridge and to anticipate its replacement before the CO 2 is no longer adsorbed and gradually fills the tank 5.

Claims

1. Portable oxygen storage cartridge (1) comprising: - a cartridge body (13) delimiting an internal volume (12) for storage of oxygen and comprising a first gas port (1-1) and a second gas port (1-2) in fluidic communication with the internal volume (12), - at least one gas flow control valve (2, 3) arranged in each of said first and second gas ports (1-1; 1-2) in order to control the flow of gas entering the internal volume (12) and / or exiting the internal volume (12) of the cartridge body (13), and - at least one adsorbent bed (14) containing at least one first adsorbent (14-1) and arranged in the internal volume (12) of the cartridge body (13), said first adsorbent (14-1) having an adsorption capacity for gaseous CO2 greater than an adsorption capacity for gaseous oxygen, characterized in that: - it further comprises at least one bypass line (71) fluidically connected at connection sites (42, 62) located upstream of each of said first and second gas ports (1-1; 1-2) such that a portion of the gas entering the internal volume (12) through either of said first and second gas ports (1-1; 1-2) is diverted and flows within said at least one bypass line (71), and - at least a part of said at least one bypass line (71) is formed of a transparent material and contains at least one second adsorbent material (75) and at least one saturation indicator material.

2. Cartridge according to Claim 1, characterized in that the cartridge (1) comprises a central chamber (124) containing said at least one adsorbent bed (14) containing said at least one first adsorbent (14-1), a first gas collection chamber (121) and a second gas collection chamber (122), the central chamber (124) being located between the first and second gas collection chambers (121, 122).

3. Cartridge according to either of the preceding claims, characterized in that said at least one first adsorbent (14-1) comprises particles of at least one zeolite.

4. Cartridge according to Claim 1, characterized in that said at least one second adsorbent material (75) contained in the bypass line (71) comprises soda lime.

5. Cartridge according to Claim 1, characterized in that said at least one saturation indicator material contained in the bypass line (71) comprises a mixture containing calcium hydroxide and ethyl violet.

6. Cartridge according to any one of Claims 1, 4 and 5, characterized in that said at least one second adsorbent material (75) and said at least one saturation indicator material are mixed with each other in the bypass line (71).

7. Cartridge according to Claim 6, characterized in that the bypass line (71) comprises a particulate mixture containing calcium hydroxide (CaOH)2, ethyl violet and lithium chloride (LiCl).

8. Cartridge according to Claim 7, characterized in that the bypass line comprises at least about 95% by weight calcium hydroxide (CaOH)2, less than about 3% by weight lithium chloride (LiCl), and up to about 1% by weight ethyl violet.

9. Cartridge according to any one of Claims 6 to 8, characterized in that the saturation indicator material reacts by progressively changing colour as the CO2 is trapped by the soda lime particles causing a change in pH.

10. Cartridge according to Claim 9, characterized in that the saturation indicator material reacts by progressively changing colour from a whitish colour to a violet colour.

11. Cartridge according to Claim 1, characterized in that the transparent material is a polymer, preferably a polycarbonate.

12. Cartridge according to Claim 1, characterized in that the bypass line (71) comprises a graduated marking.

13. Emergency oxygen delivery assembly (50) comprising a portable oxygen storage cartridge (1) for storing oxygen, according to any one of the preceding claims, fluidically connected, via said first and second gas ports (1-1; 1-2) of the cartridge (1), to a gas reservoir (5) and to a respiratory interface (25).

14. Delivery assembly according to Claim 13, characterized in that the gas reservoir is of the flexible envelope type.

15. Delivery assembly according to Claim 13, characterized in that the respiratory interface is a breathing mask, in particular a nose mask or face mask.