Gas injection device, assembly and associated method

Abstract

The present invention relates to a device (16) for injecting gas under the skin, comprising a fluidic system for delivering a dose of gas, comprising: - a gas tank (18) having a predefined tank volume (V1), the tank being configured to receive a gas at a given tank pressure (P1); - a delivery module (20) including a gas injection duct (30) connected upstream to the gas delivery outlet (24), the gas injection duct being equipped with an injection valve (34), and a gas outlet duct (32), the gas injection duct being connected downstream to the gas outlet duct, the injection valve being capable of being actuated so as to allow gas flow to the outlet duct.

Description

[0001] TITLE: Gas injection device, assembly and associated method

[0002] The present invention relates to a device for injecting gas, particularly carbon dioxide, intended for an injection of gas under the skin, comprising a fluidic system intended to deliver a dose of gas having a defined volume, comprising:

[0003] - a gas tank having a predefined tank volume V1, the tank having a gas delivery outlet and being configured to receive a pressurized gas at a given tank pressure P1;

[0004] - a delivery module including a gas injection duct connected upstream to the gas delivery outlet, the gas injection duct being equipped with an injection valve, and a gas outlet duct outside the fluidic system, the gas injection duct being connected downstream to the gas outlet duct, the injection valve being capable of being actuated from a closed rest configuration, wherein it blocks gas flow from the tank to the gas outlet duct and an open configuration, wherein it allows gas flow to the outlet duct,

[0005] Such a device is intended to inject a defined volume of gas under the skin, and particularly for performing self-injection. The gases capable of being injected are particularly chosen from biocompatible gases such as carbon dioxide, nitrogen oxide, nitrogen monoxide, oxygen, or hydrogen. Advantageously, the injected gas is carbon dioxide.

[0006] Injecting gas, particularly carbon dioxide, under the skin is a cosmetic method used in the esthetic treatment of different skin problems, in particular dark circle reduction.

[0007] Dark circles are a facial feature frequently found in the population. The appearance of dark circles, exacerbated by physiological aging of the face, affects men and women of all ages and is often a substantial esthetic concern due to the tired appearance that they give the eyes.

[0008] To this end, injecting gas, particularly carbon dioxide, into the stratum corneum, which is the outer layer of the epidermis, particularly helps enhance skin oxygenation and promotes enhanced blood circulation, which enhances the esthetic appearance of the skin in treated zones.

[0009] Injecting carbon dioxide also provides collagen stimulation, and anti-inflammatory properties. The clinically observed cosmetic benefits are enhanced under-eye circle pigmentation, brightening of the eye contour.

[0010] Injected into the skin layers, gas advantageously acts upon physical, mechanical, and / or optical skin characteristics, particularly dark circles, both internally and externally, particularly on elasticity, volumic suppleness, tonicity, firmness, brightness, radiance, but also upon the appearance of the skin surface, by enhancing its softness, texture, radiance, and / or color.Such injections being aimed at introducing gas into the outermost layer of the skin, the injection depth is very shallow. Generally, such methods are implemented by injection using a short needle, known as a microneedle, having for example a length between 0.1 mm and 10 mm.

[0011] In order to produce the desired visual effects, and to avoid risks in respect of the user, it is necessary for the injection device to deliver a calibrated gas volume in a precise and reproducible manner.

[0012] The aim of the invention is particularly to provide a device having a fluidic system not including an active component for delivering a calibrated gas volume at a given flow rate.

[0013] To this end, the invention relates to a device of the aforementioned type, characterized in that the delivery module includes an injection pressure regulator mounted on the outlet duct, the injection pressure regulator being configured to open spontaneously when the pressure in the outlet duct between the injection duct and the injection pressure regulator is greater than a predetermined threshold pressure P3, the predetermined threshold pressure P3 being less than the tank pressure P1 , the injection pressure regulator being configured to close spontaneously when the pressure in the outlet duct between the injection duct and the injection pressure regulator is less than or equal to the predetermined threshold pressure P3.

[0014] The injection pressure regulator on the outlet duct ensures, in a purely passive manner, without requiring active components, and reproducibly, the delivery of a calibrated quantity of gas.

[0015] The use of such a regulator simplifies the fluidic system and therefore reduces its cost. The gas volume delivered by the fluidic system can also be adjusted by sizing the pressures P1 and P3, in order to ensure delivery of the appropriate quantity of gas.

[0016] According to one variant, the delivery module comprises a purge generation duct, connected upstream to the gas injection duct, and connected downstream to the outlet duct, the purge generation duct being equipped with a purge regulator, the purge pressure regulator being configured to open spontaneously when the pressure in the purge generation duct between the injection duct and the purge pressure regulator is greater than a predetermined intermediate pressure P2, the predetermined intermediate pressure being less than the tank pressure P1 and being greater than the predetermined threshold pressure P3, the purge pressure regulator being configured to close spontaneously when the pressure in the purge generation duct between the injection duct and the purge pressure regulator is less than the predetermined intermediate pressure P2.The purge duct, equipped with a purge regulator, performs the cleaning of the fluidic system, before gas injection under the skin, by ejecting any dust present in the gas delivery outlet, or residue from a previous injection.

[0017] The choice of pressures P1 , P2, and P3 makes it possible to size the gas volume intended for purging and render it reproducible thanks to the presence of the purge regulator.

[0018] According to one variant, the device comprises the following feature:

[0019] - the purge generation duct comprises a purge valve capable of being actuated between a closed rest configuration, wherein it blocks gas flow from the tank to the outlet duct and a flow configuration wherein it allows gas flow to the outlet duct, the purge valve being located between the tank and the purge pressure regulator.

[0020] The presence of a purge valve on the purge duct makes it possible to trigger purging only when the purge valve is in the flow configuration. This purge valve therefore makes it possible to save gas, compared to a system wherein purging would be performed continuously.

[0021] According to one variant, the device comprises the following feature:

[0022] - the purge valve is capable of being actuated separately from the injection valve, between a first state of the fluidic system wherein the purge valve occupies the flow configuration and the injection valve occupies its closed configuration and a second state of the fluidic system wherein the injection valve occupies its open configuration, the purge valve advantageously occupying its flow configuration. Actuating the purge valve when the injection valve is in the closed configuration particularly makes it possible to perform purging following injection, to remove residue resulting from the injection.

[0023] According to one variant, the device comprises the following feature:

[0024] - the purge generation duct is devoid of a valve capable being actuated between the tank and the outlet duct.

[0025] The lack of a purge valve simplifies the system, and ensures that purging is performed continuously, as long as the tank can supply enough gas at the pressure P2. Thus, there cannot be any deposit, for example dust, at the gas outlet duct.

[0026] According to one variant, the device comprises the following feature:

[0027] - the volumes defined by the purge generation duct upstream and downstream of the purge pressure regulator are configured to be constant between the predetermined threshold pressure P3 and the given tank pressure P1.Keeping the aforementioned volumes constant over the defined pressure range ensures that the gas quantity ejected during purging is repeatable and simple to determine, without having to account for volume variation.

[0028] According to one variant, the device comprises the following feature:

[0029] - the volumes defined by the gas injection duct upstream and downstream of the injection valve and the volume defined by the outlet duct upstream of the injection pressure regulator are configured to be constant between the predetermined threshold pressure P3 and the given tank pressure P1:

[0030] Thus, the gas quantity ejected following actuation of the activation valve is repeatable and simple to determine, without having to account for volume variation.

[0031] According to one variant, the device comprises the following feature:

[0032] - the outlet includes a member for fastening a microneedle defining an orifice for delivering the gas dose.

[0033] The member for fastening a microneedle guarantees the flow of the delivered gas quantity via a microneedle, in order to carry out a subcutaneous gas injection.

[0034] According to one variant, the device comprises the following feature:

[0035] it comprises a microneedle detachably mounted on the fastening member.

[0036] The fastening member is thus adapted for replacing the microneedle, particularly in order to change the microneedle between several uses, thus enhancing safety.

[0037] In addition, detaching the microneedle makes it possible to handle and store the device while avoiding involuntary needle pricks.

[0038] According to one variant, the device comprises the following feature:

[0039] - the tank includes a filling nozzle intended to be connected to a gas refilling apparatus.

[0040] The fluidic system can thus be refilled easily between several uses, without needing to have a removable tank.

[0041] The invention also relates to an assembly comprising:

[0042] - a device as described above, the tank including a filling nozzle and

[0043] - a gas refilling apparatus having a gas delivery head,

[0044] wherein the gas delivery head is configured to be connected to the filling nozzle, in order to fill the predefined tank volume V1 of the tank of the fluidic system with gas at the given tank pressure P1.

[0045] The user thus has a simple tank refilling option, ensuring that the tank of volume V1 is filled with gas at the tank pressure P1, the pressure and volume being sized for ejecting the desired gas volume.According to one variant, the device comprises a gas capacity defining an internal volume containing gas at a capacity pressure PO greater than the given tank pressure P1 , and a gas capacity pressure regulator interposed between the gas capacity and the gas delivery head, the gas capacity pressure regulator being configured to deliver gas at the given tank pressure P1 to the gas delivery head.

[0046] The pressure regulator makes it possible to fill with gas in a purely passive manner, without any active components, which contributes to the simplicity and robustness of the assembly.

[0047] The invention also relates to a method for injecting a gas dose comprising the following steps:

[0048] - holding by a user of a device as described above, the predefined tank volume V1 receiving a pressurized gas at the given tank pressure P1;

[0049] - actuating the injection valve from the closed rest configuration, wherein it blocks gas flow from the tank to the outlet duct and the open configuration, wherein it allows gas flow to the outlet duct;

[0050] - spontaneous opening of the injection pressure regulator by establishing in the outlet duct between the injection duct and the injection pressure regulator a pressure greater than the predetermined threshold pressure P3 and delivery of the gas dose having a predefined volume by the fluidic system via the outlet duct;

[0051] - spontaneous closure of the injection pressure regulator when the pressure in the outlet duct between the injection duct and the injection pressure regulator is less than the predetermined threshold pressure P3.

[0052] The method according to the invention ensures the injection of a defined gas quantity thanks to a passive system, particularly without adding active electronic components in respect of regulation in the fluidic system.

[0053] According to one variant, the method comprises the following feature:

[0054] - the delivery module comprises a purge generation duct, connected upstream to the gas injection duct, and connected downstream to the outlet duct, the purge generation duct being equipped with a purge pressure regulator, the method including, before the actuation of the injection valve, spontaneous opening of the purge pressure regulator by establishing a pressure in the purge generation duct between the injection duct and the purge pressure regulator greater than the predetermined intermediate pressure P2, then spontaneous opening of the injection pressure regulator by establishing in the outlet duct between the injection duct and the injection pressure regulator a pressure greater than the predetermined threshold pressure P3, optionally by opening a purge valvedisposed between the tank and the purge pressure regulator, and delivery of a volume of purge gas by the fluidic system via the outlet duct before spontaneous closure of the injection pressure regulator when the pressure in the outlet duct between the injection duct and the injection pressure regulator is less than the predetermined threshold pressure P3

[0055] - - spontaneous closure of the purge pressure regulator when the pressure in the purge generation duct between the injection duct and the purge pressure regulator is less than the predetermined intermediate pressure P2.

[0056] Generating a purge enhances device hygiene, it may be performed continuously in order to maximize safety or only be performed by opening a purge valve, in order to save gas.

[0057] According to one variant, the method comprises the following feature:

[0058] - the tank includes a filling nozzle, the method including, after delivering the gas dose having a predefined volume, connecting a gas delivery head of a gas filling apparatus to the filling nozzle and filling the predefined tank volume V1 of the fluidic system with gas at the tank pressure P1

[0059] The user can thus refill the device easily following a gas injection, to fill the tank at the desired tank pressure P1. The method therefore makes it possible to deliver the same gas quantity several times.

[0060] The invention also relates to a device for injecting gas, particularly carbon dioxide, intended for an injection of gas under the skin, comprising:

[0061] - a body, extending about a central axis,

[0062] - an application head, located at an axial end of the body and defining a bearing surface of the device on a body surface,

[0063] - a fluidic system extending in the body about the central axis, the fluidic system comprising a gas tank configured to hold a defined gas quantity, and having a needle fastening member axially located on the application head side, intended to receive a microneedle and a gas dispensing system fluidically connecting the tank to the needle fastening member to inject gas from the tank into the microneedle,

[0064] - an actuation member mounted on the body about the central axis, the actuation member comprising an internal portion located inside the body and an actuation portion located outside the body at the end of the body opposite the application head, the actuation member being movable in translation along the central axis about the fluidic system, - a detachable microneedle, having a length less than 250 pm, configured to be fastened onto the needle fastening member within the fluidic system so as to be in fluidic communication with the gas tank.The aforementioned gas injection device is characterized in that the fluidic system is mounted movable in translation along the central axis relative to the body, by moving the actuation portion of the actuation member, between a rest configuration wherein the fastening member is in a retracted position, the microneedle fastened onto the fastening member being received in the body and / or in the application head, and a dispensing configuration wherein the fastening member is in a deployed position, the microneedle projecting axially relative to the bearing surface of the application head, the gas dispensing system being active between the rest configuration and the dispensing configuration to deliver a gas dose from the tank to the fastening member, the gas dose being intended to be delivered via the microneedle, to inject the gas dose under the body surface.

[0065] Advantageously but not necessarily, the gas tank has a predefined volume V1, the tank having a gas delivery outlet and being configured to receive a pressurized gas at a given tank pressure P1 and the fluidic system includes a delivery module including a gas injection duct connected upstream to the gas delivery outlet, the gas injection duct being equipped with an injection valve, and a gas outlet duct outside the fluidic system, the gas injection duct being connected downstream to the gas outlet duct, the injection valve being capable of being actuated from a closed rest configuration, wherein it blocks gas flow from the tank to the gas outlet duct and an open configuration, wherein it allows gas flow to the outlet duct, the delivery module including an injection pressure regulator mounted on the outlet duct, the injection pressure regulator being configured to open spontaneously when the pressure in the outlet duct between the injection duct and the injection pressure regulator is greater than a predetermined threshold pressure P3, the predetermined threshold pressure P3 being less than the tank pressure P1 , the injection pressure regulator being configured to close spontaneously when the pressure in the outlet duct between the injection duct and the injection pressure regulator is less than or equal to the predetermined threshold pressure P3.

[0066] The presence of a movable fluidic system in the body of the device and capable of being actuated simply by the user by means of the transporting member makes it possible at the same time to protect the microneedle before use, while ensuring a reproducible movement of the microneedle toward the user’s skin during transport and simultaneously a controlled injection of gas, reproducing that performed by medical personnel.

[0067] The fluidic system having its own tank, this injection is carried out without needing to connect the device to a gas source before injection. Thus, the device is simple to use and ergonomic, while ensuring user safety and needle movement reproducibility, even fora user who is not medically trained.In the device according to the invention, the application surface further ensures precise and stable positioning with regard to the zone to be treated, which guarantees precision and safety of use, while reducing operating errors.

[0068] According to one variant, the device comprises the following feature:

[0069] the fastening member is movable in rotation about the central axis between an intermediate configuration of the actuation member and the dispensing configuration of the actuation member, the microneedle being advantageously in the deployed position in the intermediate configuration.

[0070] A rotation of the microneedle allows the microneedle to penetrate the skin more effectively. Indeed, a microneedle having small dimensions, applying a simple translation may prove to be insufficient to allow the needle to penetrate the skin.

[0071] According to one variant, the device comprises the following feature:

[0072] the internal portion of the actuation member defines a helical groove about the central axis and the fluidic system includes a first guide pin inserted into the helical groove, the body defining a groove, preferably L-shaped, having an axial segment parallel to the central axis and a circumferential segment about the central axis, the fluidic system including a second guide pin inserted into the axial segment between the rest configuration and the intermediate configuration and inserted into the circumferential segment between the intermediate configuration and the dispensing configuration.

[0073] Thus, the system for driving the fastening member in translation and then in rotation only contains mechanical components and makes it possible to apply a translation followed by a rotation by simply pressing on the actuation portion.

[0074] According to one variant, the device comprises the following feature:

[0075] the gas dispensing system is configured to perform a gas purge intended to purge the fastening member and the microneedle between the rest configuration and the dispensing configuration.

[0076] Such a purge makes it possible to clean the microneedle by ejecting residue from previous injections, or dust which may have entered the microneedle. This enhances hygiene during device use.

[0077] According to one variant, the device comprises the following feature:

[0078] the application head is removably fastened to the axial end of the body.

[0079] Having a removable application head makes access to the fastening member simpler for the user, allowing easier fastening or removal of the microneedle.

[0080] According to one variant, the sealing cap comprises the following feature:the application head is made at least partially of a deformable material, such that applying a force along the central axis generates a radial force directed away from the central axis on the bearing surface.

[0081] Use of deformable material induces a deformation of the application head when a pressure is applied by the user, for example during positioning of the bearing surface. This deformation applies a radial force which stretches the skin. Stretching the skin makes needle penetration easier.

[0082] According to one variant, the device comprises the following feature:

[0083] the fastening member comprises a tip configured for fastening the microneedle, in particular a LUER® tip.

[0084] The presence of such a tip makes it possible to control the type of microneedle fastened to the apparatus, particularly using a standardized system.

[0085] According to one variant, the device comprises the following feature:

[0086] an indicator configured to provide representative information of the gas quantity present in the tank.

[0087] Such an indicator is useful for the user, who can for example receive audible or haptic feedback when all the gas has been injected. This indicator also serves as a safety system, to indicate that the gas tank is correctly filled.

[0088] According to one variant, the device comprises the following feature:

[0089] an indicator configured to provide representative information of the positioning of the bearing surface of the device on the application zone, particularly comprising a force sensor.

[0090] Accurate positioning of the bearing surface on the application zone is necessary in order to render the device usable for self-injection purposes.

[0091] In particular, the force applied on the bearing surface contributes to positioning stability during the gas injection operation in the application zone.

[0092] According to one variant, the device comprises the following feature:

[0093] a use control system configured to limit the number of uses of the device without refilling.

[0094] Multiple uses of the apparatus without refilling must be avoided, because an insufficient quantity of gas is then likely to be injected.

[0095] According to one variant, the device comprises the following feature:

[0096] the fluidic system comprises a gas filling nozzle in the tank, the filling nozzle projecting axially from the body, opposite the application head.The gas filling nozzle allows regular filling of the gas tank by inverting it and applying a force to connect the tip with a gas orifice connected to a gas capacity. Thus, the action is simple, and the user can conduct several injections before refilling.

[0097] The invention also relates to an injection assembly comprising an injection device as defined above and a docking station, the docking station comprising;

[0098] - a receiving area for receiving the injection device,

[0099] - a gas capacity defining a gas delivery head configured to cooperate with the fluidic system to deliver a determined quantity of gas into the fluidic system tank,

[0100] - a compartment for receiving the microneedle received in a protective case, configured to fasten the microneedle to the fastening member by holding the protective case,

[0101] - a compartment for deactivating the microneedle after use, configured to remove the microneedle from the fastening member.

[0102] The gas injection system provides the user with all the necessary utilities for the injection device in a docking station, in a convenient and secured manner.

[0103] In particular, fastening the microneedle is facilitated by the receiving compartment, and safety enhanced by the presence of a compartment for deactivating the microneedle.

[0104] According to one variant, the assembly comprises the following feature:

[0105] the docking station includes a locking fork of a microneedle case, disposed in the compartment for receiving the microneedle, the protective case being capable of being inserted into the locking fork to be locked by the locking fork.

[0106] The locking fork holds the microneedle and its case in the docking station, such that the fork is in contact with the protective case so as not to contaminate the microneedle. The risk of microbial contamination is therefore reduced.

[0107] According to one variant, the assembly comprises the following feature:

[0108] the docking station comprises a wedging fork of the microneedle after use, disposed in the deactivation compartment, the fastening member equipped with the microneedle being capable of being inserted into the wedging fork by wedging the microneedle bearing on the wedging fork.

[0109] Thus, the microneedle may be fastened to the fastening member and then removed using the wedging fork to remove the protective case. In this way, the user does not come into direct contact with the microneedle, reducing risks of injuries and contamination of the microneedle.

[0110] According to one variant, the assembly comprises the following feature:

[0111] the docking station comprises a rupture deformation track of the microneedle, disposed in the deactivation compartment.The rupture deformation track makes it possible to deactivate the microneedle by deformation when it is removed from the device, thus, microneedles cannot cause injuries, particularly when the user must subsequently handle the microneedle.

[0112] According to one variant, the assembly comprises the following feature:

[0113] a sterilization system for cleaning the fastening member and / or the microneedle. Sterilizing the fastening member avoids contaminating the microneedle with elements present in the fastening member and which would be displaced by the pressure of the injected gas.

[0114] The invention also relates to a non-therapeutic esthetic method for injecting gas in a body surface, comprising the following steps:

[0115] - providing an injection device as defined above;

[0116] - fastening a microneedle onto the fastening member of the device,

[0117] - preferably, filling the gas tank with gas,

[0118] - placing the bearing surface in contact with an application zone located on the user’s skin,

[0119] - pressing by the user on the actuation portion of the actuation member between the rest configuration and the dispensing configuration, in order to insert the microneedle into the application zone and to inject gas into the application zone,

[0120] then,

[0121] - deactivating the microneedle and removing the microneedle from the fastening member.

[0122] The method of use of the device described above for purely cosmetic purposes is adapted for performing repeated self-injections, by implementing easy refilling of the device between applications. This method also contributes to user safety, because the microneedle, a potentially hazardous element if mishandled, is systematically deactivated when the injection device is removed.

[0123] The invention will become more apparent upon reading the following description, given solely as a non-limiting example, and made with reference to the drawings, wherein:

[0124] [Fig. 1] Figure 1 is a schematic representation of the pneumatic circuit of a first gas injection assembly according to the invention,

[0125] [Fig. 2] Figure 2 is a schematic representation of the pneumatic circuit of a second gas injection assembly according to the invention, different from that of Figure 1,

[0126] - [Fig. 3] Figure 3 is a perspective view of a third gas injection assembly according to the invention, and- [Fig. 4] [Fig. 5] [Fig.6] Figures 4 to 6 are sectional views along an axial mid-plane of the third injection device according to the invention, during the implementation of a gas injection into the skin using a microneedle.

[0127] Hereinafter, pressures are expressed in absolute bar. The terms “upstream” and “downstream” generally mean the normal direction of circulation of the fluid in the injection assembly 10.

[0128] A first gas injection assembly 10 according to the invention is illustrated in Figure 1. The assembly 10 is particularly intended to deliver a calibrated gas quantity via a microneedle in order to carry out a subcutaneous injection, for example of carbon dioxide for esthetic treatment purposes.

[0129] The gases capable of being injected under the skin are particularly chosen from biocompatible gases such as carbon dioxide, nitrogen oxide, nitrogen monoxide, oxygen, or hydrogen. Advantageously, the injected gas is carbon dioxide.

[0130] With reference to Figure 1, the assembly 10 comprises a gas injection device 12, configured to be handled by a user, and a gas refilling apparatus 14 configured to be placed in fluidic communication with the device 12.

[0131] The assembly 10 is particularly adapted for delivering a precise gas quantity in a reproducible manner using the device 12, the device 12 being refillable by connecting it to the refilling apparatus 14.

[0132] The device 12 is therefore movable relative to the refilling apparatus 14 between a refilling configuration connected to the refilling apparatus 14 and a use configuration disconnected from the refilling apparatus 14.

[0133] The device 12 comprises a gas tank 18 and a fluidic system 16 intended to eject a defined gas quantity from the tank 18. The device 12 here comprises a housing (not shown) containing the tank 18 and the fluidic system 16. The housing is configured to allow joint movement of the tank 18 and the fluidic system 16 toward a body surface of the user.

[0134] To this end, the fluidic system 16 includes a delivery module 20 which makes it possible to deliver the gas quantity from the tank 18 outside the device 12 and, in this example, a fastening member 22 of a microneedle.

[0135] The fastening member 22 defines a gas outlet orifice outside the delivery module 20. Alternatively, the delivery module 20 is devoid of a fastening member 22, while defining a gas outlet orifice.

[0136] The tank 18 defines a volume intended to receive gas subjected to a tank pressure P1. For example, the tank pressure P1 is between 3 bar and 4 bar, particularly equal to 3.4bar. The volume of the tank 18 is constant at least up to the pressure P1 , for example due to the rigidity of its walls.

[0137] The tank 18 comprises a gas delivery outlet 24, placed in fluidic communication with the delivery module 20, and a filling nozzle 26, intended to be placed in fluidic communication with the refilling apparatus 14, in order to refill the tank 18 with pressurized gas.

[0138] The delivery module 20 comprises a gas injection duct 30 connected upstream to the delivery outlet 24 of the tank 18 and a gas outlet duct 32, the gas injection duct 30 being connected downstream to the gas outlet duct 32.

[0139] The delivery module 20 further comprises a purge generation duct 44, parallel to the gas injection duct 30, connected upstream to the delivery outlet 24 of the tank 18 and downstream to the gas outlet duct 32.

[0140] The gas injection duct 30 is equipped with an injection valve 34, capable of being actuated between a closed rest configuration and an open configuration wherein the tank 18 and the gas outlet duct 32 are placed in fluidic communication via the injection duct 30.

[0141] The gas injection duct 30 has an upstream portion 35, located between the tank 18 and the injection valve 34 and a downstream portion 36, located between the injection valve 34 and the gas outlet duct 32.

[0142] The upstream portion 35 is fluidically connected to the tank 18, it is thus intended to receive the gas at the tank pressure P1 from the tank 18.

[0143] In the closed configuration of the injection valve 34, the downstream portion 36 is fluidically isolated from the upstream portion 35.

[0144] The outlet duct 32 leads to the fastening member 22, which defines the gas outlet outside the device 12 via the outlet orifice.

[0145] The fastening member 22 is advantageously configured to receive removably a microneedle having an internal conduit making it possible for gas to flow via the outlet duct 32, with a view to its injection under the user’s skin.

[0146] Examples of microneedles are described in documents EP 2 594 313 or US 8 236 368.

[0147] The outlet duct 32 is equipped with an injection pressure regulator 38, disposed upstream of the fastening member 22.

[0148] The injection pressure regulator 38 is configured to regulate the upstream pressure at a threshold pressure value P3, for example between 1 bar and 2 bar, particularly equal to 1.7 bar. This pressure regulation is performed passively, without using active electronic components. For this purpose, the injection pressure regulator 38 is configured to open when the upstream pressure is greater than P3 and to close when the upstream pressureis less than or equal to P3. Thus, the pressure in the portion of the outlet duct 32 located upstream of the injection pressure regulator 38 and in the downstream portion 36 of the injection duct 30 is kept less than or equal to P3.

[0149] The threshold pressure P3 is sized to be less than the tank pressure P1. Therefore, actuating the injection valve 34 to switch it to the open configuration causes the downstream portion 36 and the upstream portion 35 to be placed in communication. The pressure in the downstream portion 36 is then greater than the threshold pressure P3, and the injection pressure regulator 38 opens to regulate the pressure in the downstream portion 36 at the threshold pressure P3.

[0150] The portion of the outlet duct 32 located upstream of the injection pressure regulator 38 and the downstream portion 36 of the gas injection duct 30 define a volume V3 together.

[0151] The volume V3 is advantageously constant at least up to the pressure P3, which is ensured by a sufficient rigidity of the gas injection duct 30 and the gas outlet duct 32 so that their walls are not deformed when a threshold pressure P3 is applied thereon.

[0152] The purge generation duct 44 is here connected upstream to the gas injection duct 30 at an upstream connection point 46 and downstream to the gas outlet duct 32 at a downstream connection point 48.

[0153] The purge generation duct 44 is intended to circulate a quantity of purge gas from the tank 18 to the fastening member 22, the quantity of purge gas being intended to remove impurities that might be found therein from the outlet duct 32.

[0154] The purge generation duct 44 is equipped with a purge pressure regulator 50 which regulates the upstream pressure to an intermediate pressure P2, for example between 2 and 3 bar, particularly equal to 2.35 bar. This pressure regulation is performed passively, without using active electronic components.

[0155] The operation of the purge pressure regulator 50 is analogous to that of the injection pressure regulator 38. It blocks fluid flow by being closed when the upstream pressure is less than or equal to the intermediate pressure P2, and allows the fluid to flow and is opened when the upstream pressure is greater than the intermediate pressure P2.

[0156] In the embodiment shown in Figure 1, the purge generation duct 44 is equipped with a purge valve 51 located upstream of the purge pressure regulator 50. The purge valve 51 defines an intermediate portion 49 of the purge generation duct 44 between the purge valve 51 and the purge pressure regulator 50 which has a volume V2.

[0157] The volume V2 is advantageously constant at least up to the pressure P2, which is ensured by a sufficient rigidity of the purge generation duct 44 so that its walls are not deformed when a pressure P2 is applied thereon.The fluid intended to be received in the volume V2 of the intermediate portion 49 is subjected to a pressure less than or equal to P2, due to the purge pressure regulator 50. The intermediate pressure P2 is greater than the threshold pressure P3 and less than the tank pressure P1.

[0158] The purge valve 51 is capable of being actuated between a sealed rest configuration, wherein it blocks gas flow from upstream to the purge pressure regulator 50 and an open flow configuration, wherein the tank 18 and the intermediate portion 49 are in fluidic communication.

[0159] The tank 18, the upstream portion 35 of the gas injection duct 30, and the upstream portion of the purge generation duct 44 upstream of the purge valve 51 are in fluidic communication and define a gas volume V1.

[0160] The volume V1 is advantageously constant at least up to the pressure P1, which is ensured by a sufficient rigidity of the tank 18, the gas injection duct 30, the purge generation duct 44 so that their walls are not deformed when a pressure P1 is applied thereon.

[0161] With reference to Figure 1, the refilling apparatus 14 is intended to supply the tank 18 with gas so that it reaches the tank pressure P1.

[0162] It forms for example a docking station intended to accommodate the injection device 12.

[0163] To this end, the refilling apparatus 14 comprises a gas capacity 52, a gas delivery head 54 and a refilling duct 56 placing the gas capacity 52 and the gas delivery head 54 in communication.

[0164] The gas capacity 52 has a volume VO of gas subjected to a capacity pressure P0. It is configured to supply the gas required to fill the tank 18 of the device 12. The capacity pressure P0 is greater than the tank pressure P1, particularly greater than 5 times the tank pressure P1, for example between 30 and 70 bar, particularly equal to 50 bar.

[0165] The gas capacity 52 is for example received in the refilling apparatus 14 in a removable manner, so as to be able to replace it readily when it no longer contains enough gas to fulfill its refilling function of the tank 18.

[0166] The gas delivery head 54 is configured to be removably connected to the filling nozzle 26 of the tank 18 to place the refilling duct 56 and the tank 18 in fluidic communication.

[0167] The refilling duct 56 is equipped with a gas capacity pressure regulator 58, located between the gas capacity 52 and the gas delivery head 54. The gas capacity pressure regulator 58 is configured to apply a tank pressure P1 downstream.

[0168] Thus, the refilling apparatus 14 is capable of applying a tank pressure P1 in the volume V1 of the tank 18 by connecting the gas delivery head 54 and the filling nozzle 26.A method for injecting a dose of gas using an assembly 10 according to the embodiment illustrated in Figure 1 will now be described.

[0169] The user seeking to dispense the dose of gas takes hold of device 12 in an initial state.

[0170] In the initial state of the fluidic system 16, the injection valve 34 and the purge valve 51 are in their closed rest configuration and seal off the gas flow. The volumes V2 and V3 receive gas subjected to a threshold pressure P3 and the volume V1 receives gas at the tank pressure P1 from the tank 18.

[0171] The user first activates the purge valve 51 to switch it to its flow configuration. The fluidic system 16 is then in a first state, placing the volumes V1 and V2 in fluidic communication.

[0172] The gas contained in the volume V1 + V2 is characterized by a pressure Pint:

[0173]

[0174] The values of the pressures P1, P2 and P3 and the volumes V1 and V2 are sized such that the pressure Pintis greater than the intermediate pressure P2.

[0175] The purge pressure regulator 50 then opens spontaneously until the pressure Pintis equal to the intermediate pressure P2. The purge gas volume Vp2, at the intermediate pressure P2, which flows through the purge pressure regulator 50 then satisfies the following relationship:

[0176] P1*V1+P3*V2=P2*(V1+V2+Vp2)

[0177] The purge gas volume can therefore be expressed as a constant which is dependent on the predefined pressures and the constant volumes of the fluidic system:

[0178]

[0179] The gas received in the volume V3 is then subjected to a pressure greater than the threshold pressure P3 due to the switch of the purge gas volume Vp2 to the intermediate pressure P2. Thereafter, the injection pressure regulator 38 opens in order to regulate the gas pressure in the volume V3 at the threshold pressure P3.

[0180] Indeed, the gas contained in the volume V3 in the initial state is at the threshold pressure P3, the additional gas volume Vp2 flows via the downstream injection pressure regulator 38 and is dispensed via the fastening member 22, thus purging the gas outlet duct 32.

[0181] When the actuation of the purge valve 51 stops, the latter then returns to its sealed rest configuration.Thereafter, to carry out a gas injection under the skin, the user activates the injection valve 34, which switches to its open configuration. The tank 18 is then in fluidic communication with the outlet duct 32 via the gas injection duct 30 as well as the purge generation duct 44.

[0182] The purge valve 51 is in the sealed configuration and the injection valve is in the open configuration, the fluidic system 16 is then in a second state.

[0183] The injection pressure regulator 38 opens to regulate the pressure of the volume V1 + V2 + V3 at the threshold pressure P3. An injection gas volume Vi then passes through the gas outlet duct 32 and flows via the fastening member 22. The injection gas volume Vi which passes through the fastening member 22 is then equal to:

[0184]

[0185] The ejected gas quantity is therefore known and sized using the pressures applied by the injection pressure regulator 38 and the purge pressure regulator 44.

[0186] At the end of the sequence, the fluidic system 16 contains gas at the uniform threshold pressure P3.

[0187] The device 12 is then refilled, using the refilling apparatus 14, in order to fill the tank 18 at the tank pressure P1.

[0188] For this purpose, the user connects the filling nozzle 26 of the device 12 with the delivery outlet 24 of the refilling apparatus 14.

[0189] The gas capacity pressure regulator 58 switches to the open configuration, because the gas capacity pressure P0 in the gas capacity 52 is greater than the threshold pressure P3 in the tank 18. Hence, the gas capacity 52 and the tank 18 are in fluidic communication, and the tank 18 is filled with gas until it reaches the tank pressure P1.

[0190] The gas capacity pressure regulator 58 switches to the closed configuration when the gas in the tank 18 is subjected to the tank pressure P1.

[0191] The user can then detach the device 12 from the refilling apparatus 14, and the fluidic system 16 is in its initial state described above, ready to be used to deliver the quantity of purge and / or injection gas once again.

[0192] The assembly 10 shown in Figure 2 differs from that shown in Figure 1 in that the purge generation duct 44 is devoid of a purge valve 51. The tank 18, the upstream portion 35 of the gas injection duct 30, and the upstream portion of the purge generation duct 44 upstream of the purge pressure regulator 50 are in fluidic communication and define a constant volume V1 + V2. In this embodiment, the gas contained in the volume V1 + V2 is subjected to a pressure less than or equal to P2, due to the purge pressure regulator 50.A method for injecting a dose of gas using the device 12 according to the embodiment illustrated in Figure 2 will now be described.

[0193] In this embodiment, the lack of a purge valve 51 places the tank 18 and the purge generation duct 44 in fluidic communication. The volume V1 + V2 is at a pressure greater than P2. Thus, purging is performed continuously until the volume V1 + V2 reaches the intermediate pressure P2 applied by the purge pressure regulator 50.

[0194] Once purging has been performed, the user can freely actuate the injection valve 34 in order to expel the injection gas volume Vi, which is expressed as:

[0195]

[0196] Thereafter, the gas contained in the fluidic system 16 is at the threshold pressure P3, and the user can refill the tank with gas at the pressure P1 via the refilling apparatus 14, similarly to as described above.

[0197] The device 12 according to the invention makes it possible to inject a defined gas quantity very simply, using a fluidic system devoid of active components, in particular those which are purely mechanical. The refilling apparatus 14 ensures easy repeatability of gas delivery into the tank 18 for the user, ensuring delivered dose reproducibility. Thanks to the fastening member 22 which is configured to receive a microneedle, the device 12 is particularly adapted for subcutaneous gas injection.

[0198] A third gas injection assembly 210 according to the invention intended for gas injection into a skin tissue is illustrated in Figure 3. The assembly 210 is a third example of a gas injection assembly according to the invention.

[0199] The assembly 210 is particularly intended for injection, particularly self-injection, of carbon dioxide by a medically unqualified user, into the cutaneous layers of the skin, above the dermo-epidermal junction, at a depth less than or equal to 250 micrometers, more preferably 100 micrometers, and even more preferably 50 micrometers.

[0200] The injection assembly 210 comprises a docking station 212 and a gas injection device 216, designed to be held by a user’s hand to be moved facing the body surface 213 (see Figure 4) wherein the injection is to be carried out.

[0201] The body surface 213 particularly comprises at least one region exhibiting signs of skin aging and fatigue, such as dark circles, wrinkles, skin creases, particularly facial creases, or pigmentation, or even scars, for example, due to acne.

[0202] With reference to Figure 4, the injection device 216 comprises a body 218 which extends about a central axis A-A’, and a fluidic gas delivery system 220, movably mounted in the body 218. The device 216 comprises, at a distal axial end of the body 218, an application head 222, advantageously removable, and, at a proximal axial end of the body218, an actuation member 224 of the fluidic system 220 to cause gas injection in the body surface 213.

[0203] Hereinafter, the terms “internal” and “external” generally mean with reference to the central axis A-A’ of the device. The terms “distal” and “proximal” generally mean with reference to the hand of a user actuating the injection device 216, the term “proximal” then meaning closer to the user’s hand and the term “distal” meaning further away from the user’s hand and closer to the body surface 213.

[0204] The body 218 has a hollow shell 226 of cylindrical shape extending about the central axis A-A’ and a guide sleeve 228, located at a distal end of the body 218.

[0205] The cylindrical-shaped shell 226 internally delimits a rectilinear groove 227 for guiding the fluidic system 220 in translation along the axis A-A’, which extends parallel to the central axis A-A’.

[0206] The guide sleeve 228 has a substantially cylindrical shape, of which the maximum cross-section here has a diameter less than the diameter of the maximum cross-section of the shell 226. The sleeve 228 defines with the shell 226, at the distal end of the shell 226, a shoulder 236, which corresponds to the variation in cross-section of the body 218.

[0207] The guide sleeve 228 internally defines an L-shaped groove 230 for guiding the fluidic system 220 in rotation about the axis A-A’.

[0208] The groove 230 has a proximal axial segment 231, parallel to the central axis A-A’, and a distal circumferential segment 232, extending about the axis A-A’.

[0209] Furthermore, the sleeve 228 comprises here an external thread 234 for mounting the application head 222, which is here located axially between the groove 230 and the shoulder 236.

[0210] The application head 222 is a rotary part extending about the axis A-A’, when it is mounted at the distal end of the body 218.

[0211] The application head 222 has a cylindrical proximal base 240 and a distal application tip 244 on the body surface 213, extending the base 240 distally.

[0212] The base 240 has an external cross-section substantially equal to that of the shell 226 of the body. It is here equipped with an internal thread 238 on its internal surface. The internal thread 238 of the application head 222 is configured to be engaged on the external thread 234 of the sleeve 228, in order to connect the application head 222 and the body 218, in a removable manner.

[0213] In one variant (not shown), the application head 222 and the body 218 are assembled by simple mechanical embedding or, in another variant, in a non-removable manner.The application head 222 comprises a tip 244 defining a bearing surface 246 of the device 216, the bearing surface 246 having an axial opening extending along the central axis A- A’.

[0214] Advantageously, the tip 244 is formed from a deformable material, for example rubber. In this example, the tip 244 comprises a converging region toward the axis A-A’ from the base 240 and an application flange projecting radially about the axial opening. The application flange defines the bearing surface 246 which here extends annularly about the axis A-A’, transversely relative to the axis A-A’.

[0215] The actuation member 224 is configured to be moved by a user in translation along the axis A-A’ in the body 218, between a rest configuration, seen in Figure 4, an intermediate configuration, seen in Figure 5, and a gas dispensing configuration, seen in Figure 6.

[0216] The actuation member 224 includes a hollow-shaped internal portion 248 located inside the body 218 and an actuation portion 250 located outside the body 218, which partially covers the body 218 of the device 216.

[0217] The actuation portion 250 is configured to be held or pushed by a user’s fingers to cause the movement in translation of the actuation member 224 along the axis A-A’.

[0218] The internal portion 248 is interposed between the shell 226 and the fluidic system 220. It defines a helical groove 251 about the central axis A-A’.

[0219] The internal portion 248 comprises a guide pin 252 which projects radially away from the axis A-A’. The guide pin 252 cooperates with the rectilinear groove 227 of the body 218, in order to guide the actuation member 224 in translation relative to the body 218 along the axis A-A’.

[0220] The length, measured along the central axis A-A’, of the rectilinear groove 227 defines the travel of the actuation member 224 relative to the body 218 between the rest configuration and the gas dispensing configuration.

[0221] The fluidic system 220 extends along the axis A-A’. It is received at least partially inside the internal portion 248 of the actuation member 224.

[0222] It has a distal end extending into the sleeve 228 and, at least in the rest configuration, a proximal end projecting axially from the body 218. It includes a gas tank for injecting pressurized gas (not shown).

[0223] The fluidic system 220 of the third injection assembly 210 comprises the gas tank. It optionally, but not necessarily, comprises a delivery module 20, identical to that of the first assembly 10 according to the invention or the second assembly 10 according to the invention.The distal end of the fluidic system 220 includes a fastening member 256, configured for fastening a microneedle 258. The fastening member 256 is located facing the axial opening arranged in the bearing surface 246.

[0224] The fastening component 256 comprises for example a fastening tip for a microneedle 258, for example a LU ER® tip. It is connected upstream to the tank of gas to be injected.

[0225] The proximal end of the fluidic system 220 includes a filling nozzle 260, which communicates to the gas tank upstream thereof.

[0226] The fluidic system 220 also includes a gas dispensing system (not seen) equipped with a dispensing valve, which makes it possible to eject a predetermined dose of gas located in the gas tank via the fastening member 256 by actuating the dispensing valve during the movement of the actuation member between the intermediate configuration and the gas dispensing configuration.

[0227] Advantageously, the fluidic system 220 includes a purge system (not seen) advantageously equipped with a purge valve, which makes it possible to eject a quantity of gas via the fastening member 256, before the gas dose, in order to clean the internal ducts of the fluidic system 220, the fastening member 256 and the microneedle 258.

[0228] Furthermore, the fluidic system 220 includes a first guide pin 262, inserted into the helical groove 251 and a second guide pin 264 inserted into the L-shaped groove 230. The guide pins 262 and 264 here project radially away from the axis A-A’.

[0229] The microneedle 258 is fastened to the fastening member 256 by its base, in a detachable manner, in order to be able to change it from one use to another. The microneedle 258 preferably has a length less than 250 pm, in particular less than 150 pm.

[0230] The microneedle 258 has an internal channel placing the base and a tip in fluidic communication, so that the gas conveyed in the fastening member 256 is ejected by the tip of microneedle 258.

[0231] The microneedle 258 is initially disposed in a protective case, of cylindrical shape, of which one end is closed, the other end being open. The protective case has a shoulder at its open end, from which the base of the microneedle 258 projects.

[0232] Examples of microneedles 258 are described in documents EP 2 594 313 or US 8 236368.

[0233] In the rest configuration, shown in Figure 4, the actuation member 224 is the most distant axially from the application head 222. The guide pin 252 is located at the proximal end of the axial groove 227.

[0234] The first guide pin 262 is located at the distal end of the helical groove 251 , closest to the application head 222. The second guide pin 264 is located at a stop in the axial segment 231 of the groove 230, at the proximal end of the axial segment 231.In this position, the microneedle 258 is located wholly in the body 218 and / or in the application head 222, and the fastening member 256 is in a retracted position. The risk of untimely needle pricks and / or damage to the needle is therefore very limited.

[0235] In the intermediate configuration, seen in Figure 5, the actuation member 224 has moved exclusively in translation toward the axis A-A’ and the application head 222, driving the fluidic system 220 distally in translation along the axis A-A’ until the second guide pin 264 comes to a stop at the distal end of the axial segment 231 of the groove 230.

[0236] In this Figure 5, the arrows associated with the body surface represent the radial force exerted by the tip 244, which is made of deformable material, when it is deformed by an axial force, for example applied by the user. This radial force is applied on the body surface 213, for example the user’s skin, to stretch it by placing it under tension.

[0237] The first guide pin 262 moreover remains located at the distal end of the helical groove 251 , closest to the application head 222. The fastening member 256 of the microneedle 258 is in a deployed position, projecting from the bearing surface 246.

[0238] In the gas dispensing configuration seen in Figure 6, the actuation member 224 is axially closest to the application head 222. The guide pin 252 is located at the distal end of the axial groove 227. In this Figure 6, the arrows associated with the body surface represent the radial force exerted on the body surface 213 induced by the deformation of the tip 244.

[0239] The fluidic system 220 has pivoted about the axis A-A’ relative to the actuation member 224 and relative to the body 218, without any axial movement relative to the body 218.

[0240] The second pin 264 is at a stop against the circumferential segment 232 of the groove 230 having moved angularly away from the axial segment 231 about the axis A-A’. The first guide pin 262 is returned toward the distal end of the helical groove 251 having pivoted about the axis A-A’.

[0241] Advantageously, the device 216 comprises a spring (not shown), interposed between the fluidic system 220 and the body 218. This spring is compressed as the fluidic system 220 is translated along the central axis A-A’ from the rest configuration to the fluid dispensing configuration. Thus, the spring spontaneously stresses the return of the fluidic system 216 and the actuation member 224 to their rest configuration in the absence of external force applied on the actuation member 224.

[0242] Advantageously, the device 216 comprises an indicator (not shown) which provides representative information of the gas quantity present in the gas tank of the fluidic system 220. The indicator is for example a luminous, audible or haptic indicator. The function of such an indicator is to tell the user that the device 216 is properly filled and thus avoid performing an incomplete injection.Alternatively, the device 216 includes an indicator which provides representative information of the suitable positioning of the bearing surface 246 relative to a chosen application zone 247. In particular, this indicator comprises a force sensor for measuring the force applied on the application zone 247.

[0243] Alternatively, the device 216 comprises a use control system configured to limit the number of uses of the device without refilling. The use control system particularly comprise a timer, in order to measure the time between two uses of the device 216 without refilling the gas tank of the fluidic system 220 or a number of movements of the actuation member 224 without refilling.

[0244] With reference to Figure 3, the docking station 212 comprises a housing which defines a receiving area 270, here in the form of a vertical notch, for accommodating the device 216, particularly when the application head 222 is detached from the body 218. This area is delimited at the bottom by a bearing surface 271 of the sleeve 228 having a through groove 272. The through groove 272 arranges a passage for the fastening member 256 of the fluidic system 220.

[0245] The housing of the docking station 212 also contains a gas capacity which has a gas delivery head 274. The filling nozzle 260 of device 216 is configured to be removably mounted on the gas delivery head 274, in order to deliver a defined gas quantity to the gas tank of the fluidic system 220.

[0246] The housing of the docking station 212 further delimits a storage hollow for the application head 222 which is here disposed between the receiving area 270 and the gas delivery head 274.

[0247] The housing of the docking station 212 also defines a receiving compartment 276 configured to guide the insertion of the microneedle 258 into the fastening member 256.

[0248] The receiving compartment 276 comprises, in its bottom, a recess 279 which accommodates the closed end of the protective case, wherein the microneedle 258 is received.

[0249] Furthermore, the receiving compartment 276 contains a locking fork 278 of the protective case. The protective case is configured to be inserted into the receiving compartment 276, between the recess 279 and the locking fork 278, with the shoulder of the protective case in contact with the locking fork 278. This allows the base of the microneedle 258 to be positioned projecting from the locking fork 278, allowing the insertion of the fastening member 256 into the base of the microneedle 258.

[0250] The housing of the docking station 212 also defines a deactivation compartment 280, configured to deactivate the microneedle 258 after use, particularly in order to prevent the occurrence of accidents associated with handling the microneedle 258. The deactivationcompartment 280 also makes it possible to separate the microneedle 258 from the fastening member 256 without contact with the user’s fingers.

[0251] In one embodiment, the deactivation compartment 280 comprises, in its bottom, a rupture deformation track of the microneedle 258. For example, this track is formed by a stud of convergent shape projecting toward a vertex which deforms the microneedle 258 when a pressure is exerted on the microneedle 258 by contact of the tip of the microneedle 258 on the track.

[0252] The deactivation compartment 280 also contains a wedging fork 282, which is configured to hold the microneedle 258 during a movement of the fastening member 256 away from the deactivation compartment 280. The base of the microneedle 258 is capable of being wedged between the wedging fork 282 and the bottom of the deactivation compartment 280, such that the wedging fork 282 holds the base of the microneedle 258 to separate the microneedle 258 during the movement of the fastening member 256 away from the deactivation compartment 280.

[0253] In one variant (not shown), the docking station 212 comprises a sterilization system for cleaning particularly the fastening member 256 of the device 216 and / or the microneedle 258. Indeed, the device 216 being intended for subcutaneous injection, sterilizing the members of the system in fluidic communication ensures enhanced safety, in particular when these members are capable of being contaminated.

[0254] A method of use by a user seeking to perform a gas injection, in particular selfinjection of gas using an assembly 210, will now be described.

[0255] The user first takes a microneedle 258 received in a protective case, to place it in the receiving compartment 276 of the docking station 212 seen in Figure 3. They wedge the protective case between the recess 279 and the locking fork 278, with the shoulder of the protective case in contact with the lower surface of the locking fork 278.

[0256] The device 216 is then removed from its receiving area 270, to place the fastening member 256 facing the base of the microneedle 258 above the receiving compartment 276.

[0257] The microneedle 258 is then fastened to the fastening member 256, for example by moving the fastening member 256 toward the recess 279.

[0258] The device 216 is then moved away from the recess 279, and the protective case is detached from the microneedle 258 while being held in the locking fork 278.

[0259] The application head 222 is then fastened onto the body 218, such that the microneedle 258 is disposed inside the application head 222 or the body 218.

[0260] The fastening member 256 is then in a retracted position wherein the microneedle 258 fastened onto the fastening member 256 is received in the application head 222.Next, the user fills the device 216 with gas, by inverting the device in order to make the filling nozzle 260 of the device 216 cooperate with the gas delivery head 274 of the docking station 212.

[0261] The gas tank of the fluidic system 220 is then filled with a specific gas quantity at a defined pressure, particularly by pressure from the device 216 on the gas delivery head 274.

[0262] With reference to Figure 4, the user positions the bearing surface 246 of the device 216 on the application zone 247 on which they wish to perform the gas injection. Preferably, they place the device 216 perpendicular to the application zone 247.

[0263] When a pressure is applied by the user, the flange of the application head 222 is deformed radially away from the axis A-A’, which applies a radial force which stretches the skin (see arrows in Figure 5). This facilitates pricking of the microneedle 258.

[0264] The user then applies a pressure on the actuation portion 250 of the actuation member 224 toward the application head 222.

[0265] The actuator 224 moves in translation along the central axis A-A’. The internal portion 248 applies an oblique force on the first guide pin 262 via the helical groove 251, which tends to drive the fluidic system 220 and the microneedle 258 mounted at the end of the fastening member 256 in translation along the central axis A-A’ relative to the body 218.

[0266] When switching from the rest configuration to the intermediate configuration, the second guide pin 264 guides the fluidic system 220 solely in translation along the axial segment 231 of the groove 230, until it arrives at a stop on the axial segment 231.

[0267] Advantageously, during the movement from the rest configuration to the intermediate configuration, the fluidic system 220 activates its purge system, in order to release a gas quantity generally less than the dose to be injected, intended to purge the fluidic system 220 as well as the microneedle 258.

[0268] The microneedle thus penetrates the stratum corneum of the skin located in the application zone 247.

[0269] Subsequently, between the intermediate configuration and the dispensing configuration, the oblique force applied on the fluidic system 220 then only causes a rotation about the axis A-A’ of the fluidic system 220 and the microneedle 258 mounted on the fastening member 256 relative to the body 218. The second pin 264 is guided along the circumferential segment of the guide sleeve 228. The rotation of the fluidic system 220 relative to the body 218 causes a movement of the first guide pin 262 along the helical groove 251.

[0270] The fastening member 256 is in a deployed position, the microneedle 258 projecting axially relative to the bearing surface 246 of the application head 222.A dose of gas from the tank of the fluidic system is sent into the microneedle 258 by the dispensing system, during the movement of the actuation member 224 from the intermediate configuration to the dispensing configuration, to be injected in the chosen application zone 247.

[0271] Once the injection has been performed, the user releases the pressure they were exerting on the actuation member 224. The actuation member 224 and the fluidic system 220 spontaneously return to the rest configuration under the action of the spring between the body 218 and the fluidic system 220.

[0272] Optionally, another injection is performed, by refilling the device 216 with gas, then implementing once again the steps detailed above.

[0273] When the user has treated the desired application zones, they remove and neutralize the microneedle 258.

[0274] For this purpose, the application head 222 is unscrewed, and the microneedle 258 is inserted into the deactivation compartment 280. A pressure of the microneedle 258 on the deformation track deactivates the microneedle 258, which is then removed by wedging its base under the wedging fork 282.

[0275] The deactivated microneedle 258 is then housed in its protective case and the user discards it.

[0276] The injection device 216 according to the invention is therefore particularly adapted to be user, in conjunction with the docking station 212, by non-specialist personnel. Indeed, it ensures a reproducible movement of appropriate amplitude to prick the user’s skin in a manner similar to an injection performed by medical personnel, by a simple translation of the actuation member 224 along the body 218 over a calibrated travel.

[0277] The application head 222 and the indicators limit the risk of untimely needle pricking and prevent unsuitable use by the user and injuries resulting from handling the microneedle

Claims

27CLAIMS1. A device (12) for injecting gas, particularly carbon dioxide, intended for an injection of gas under the skin, comprising a fluidic system (16) intended to deliver a dose of gas having a defined volume, comprising:- a gas tank (18) having a predefined tank volume V1, the tank (18) having a gas delivery outlet (24) and being configured to receive a pressurized gas at a given tank pressure P1;- a delivery module (20) including a gas injection duct (30) connected upstream to the gas delivery outlet (24), the gas injection duct (30) being equipped with an injection valve (34), and a gas outlet duct (32) outside the fluidic system (16), the gas injection duct (30) being connected downstream to the gas outlet duct (32), the injection valve (34) being capable of being actuated from a closed rest configuration, wherein it blocks gas flow from the tank (18) to the gas outlet duct (32) and an open configuration, wherein it allows gas flow to the outlet duct (32),characterized in that the delivery module (20) includes an injection pressure regulator (38) mounted on the outlet duct (32), the injection pressure regulator (38) being configured to open spontaneously when the pressure in the outlet duct (32) between the injection duct (30) and the injection pressure regulator (38) is greater than a predetermined threshold pressure P3, the predetermined threshold pressure P3 being less than the tank pressure P1 , the injection pressure regulator (38) being configured to close spontaneously when the pressure in the outlet duct between the injection duct (30) and the injection pressure regulator (38) is less than or equal to the predetermined threshold pressure P3.

2. The device (12) according to claim 1, wherein the delivery module (20) comprises a purge generation duct (44), connected upstream to the gas injection duct (30), and connected downstream to the outlet duct (32), the purge generation duct (44) being equipped with a purge regulator (50), the purge pressure regulator (50) being configured to open spontaneously when the pressure in the purge generation duct (44) between the injection duct (30) and the purge pressure regulator (50) is greater than a predetermined intermediate pressure P2, the predetermined intermediate pressure being less than the tank pressure P1 and being greater than the predetermined threshold pressure P3, the purge pressure regulator (50) being configured to close spontaneously when the pressure in thepurge generation duct (44) between the injection duct (30) and the purge pressure regulator (50) is less than the predetermined intermediate pressure P2.

3. The device (12) according to claim 2, wherein the purge generation duct (44) comprises a purge valve (51) capable of being actuated between a closed rest configuration, wherein it blocks gas flow from the tank (18) to the outlet duct (32) and a flow configuration wherein it allows gas flow to the outlet duct (32), the purge valve (51) being located between the tank (18) and the purge pressure regulator (50).

4. The device (12) according to claim 3, wherein the purge valve (51) is capable of being actuated separately from the injection valve (34), between a first state of the fluidic system (16) wherein the purge valve (51) occupies the flow configuration and the injection valve (34) occupies its closed configuration and a second state of the fluidic system (16) wherein the injection valve (34) occupies its open configuration, the purge valve (51) advantageously occupying its flow configuration.

5. The device (12) according to claim 2, wherein the purge generation duct (44) is devoid of a valve capable of being actuated between the tank (18) and the outlet duct (32).

6. The device (12) according to any one of claims 2 to 5, wherein the volumes defined by the purge generation duct (44) upstream and downstream of the purge pressure regulator (50) are configured to be constant between the predetermined threshold pressure P3 and the given tank pressure P1.

7. The device (12) according to any one of the preceding claims, wherein the volumes defined by the gas injection duct (30) upstream and downstream of the injection valve (34) and the volume defined by the outlet duct (32) upstream of the injection pressure regulator (38) are configured to be constant between the predetermined threshold pressure P3 and the given tank pressure P1.

8. The device (12) according to any of the preceding claims, wherein the outlet duct (32) includes a member (22) for fastening a microneedle defining an orifice for delivering the gas dose.

9. The device according to claim 8, comprising a microneedle detachably mounted on the fastening member (22).

10. The device (12) according to any one of the preceding claims, wherein the tank (18) includes a filling nozzle (26), intended to be connected to a gas refilling apparatus (14).

11. The device (216) according to any one of the preceding claims, comprising:a body (218), extending about a central axis (A-A’),an application head (222), located at an axial end of the body (218) and defining a bearing surface (246) of the device (216) on a body surface (213), a fluidic system (220) extending in the body (218) about the central axis (A-A’), the fluidic system (220) comprising the gas tank configured to hold a defined gas quantity, and having a needle fastening member (256) axially located on the application head (222) side, intended to receive a microneedle (258) and a gas dispensing system fluidically connecting the tank to the needle fastening member (256) to inject gas from the tank into the microneedle (258), the gas dispensing system comprising the delivery module (20);an actuation member (224) mounted on the body (218) about the central axis (A-A’ ), the actuation member (224) comprising an internal portion (248) located inside the body (218) and an actuation portion (250) located outside the body (218) at the end of the body (218) opposite the application head (222), the actuation member (224) being movable in translation along the central axis (A- A’) about the fluidic system (222),a detachable microneedle (258), having a length less than 250 pm, configured to be fastened onto the needle fastening member (256) within the fluidic system (220) so as to be in fluidic communication with the gas tank,wherein the fluidic system (220) is mounted movable in translation along the central axis (A-A’) relative to the body (218), by moving the actuation portion (250) of the actuation member (224), between a rest configuration wherein the fastening member (256) is in a retracted position, the microneedle (258) fastened onto the fastening member (256) being received in the body (218) and / or in the application head (222), and a dispensing configuration wherein the fastening member (256) is in a deployed position, the microneedle (258) projecting axially relative to the bearing surface (246) of the application head (222), the gas dispensing system being active between the rest configuration and the dispensing configuration to deliver a gas dose from the tank to the fastening member (256), the gas dose being intended to be delivered via the microneedle (258), to inject the gas dose under the body surface (213).

12. The device (216) according to claim 11, wherein the fastening member (256) is movable in rotation about the central axis (A-A’) between an intermediate configuration of the actuation member (224) and the dispensing configuration of the actuation member (224), the microneedle (258) being advantageously in the deployed position in the intermediate configuration.

13. The device (216) according to claim 12, wherein the internal portion (248) of the actuation member (224) defines a helical groove (251) about the central axis (A-A’) and the fluidic system (220) includes a first guide pin (262) inserted into the helical groove (251), the body (218) defining a groove (230), preferably L-shaped, having an axial segment (231) parallel to the central axis (A-A’) and a circumferential segment (232) about the central axis (A-A’), the fluidic system (220) including a second guide pin (264) inserted into the axial segment (231) between the rest configuration and the intermediate configuration and inserted into the circumferential segment (232) between the intermediate configuration and the dispensing configuration.

14. An injection assembly (10) comprising:a device (12) according to any one of the preceding claims, the tank (18) including a filling nozzle (26), anda gas filling apparatus (14) having a gas delivery head (54),wherein the gas delivery head (54) is configured to be connected to the filling nozzle (26), in order to fill the predefined tank volume V1 of the tank (18) of the fluidic system (16) with gas at the given tank pressure P1.

15. The assembly (10) according to claim 14, comprising a gas capacity (52) defining an internal volume containing gas at a capacity pressure P0 greater than the given tank pressure P1, and a gas capacity pressure regulator (58) interposed between the gas capacity (52) and the gas delivery head (54), the gas capacity pressure regulator (52) being configured to deliver gas at the given tank pressure P1 to the gas delivery head (54).

16. A method for injecting gas comprising the following steps:holding by a user of a device (12) according to any one of claims 1 to 10, the predefined tank volume V1 receiving a pressurized gas at the given tank pressure P1 ;31actuating the injection valve (34) from the closed rest configuration, wherein it blocks gas flow from the tank (18) to the outlet duct (32) and the open configuration wherein it allows gas flow to the outlet duct (32); spontaneous opening of the injection pressure regulator (38) by establishing in the outlet duct (32) between the injection duct (30) and the injection pressure regulator (38) a pressure greater than the predetermined threshold pressure P3 and delivery of the gas dose having a predefined volume by the fluidic system (16) via the outlet duct (32);spontaneous closure of the injection pressure regulator (38) when the pressure in the outlet duct between the injection duct and the injection pressure regulator is less than the predetermined threshold pressure P3.

17. The method according to claim 16, wherein the delivery module (20) comprises a purge generation duct (44), connected upstream to the gas injection duct (30), and connected downstream to the outlet duct (32), the purge generation duct (44) being equipped with a purge pressure regulator (50), the method including, before the actuation of the injection valve (34), spontaneous opening of the purge pressure regulator (50) by establishing a pressure in the purge generation duct (44) between the injection duct (30) and the purge pressure regulator (50) greater than the predetermined intermediate pressure P2, then spontaneous opening of the injection pressure regulator (38) by establishing in the outlet duct (32) between the injection duct (30) and the injection pressure regulator (38) a pressure greater than the predetermined threshold pressure P3, optionally by opening a purge valve (51) disposed between the tank (18) and the purge pressure regulator (50), and delivery of a volume of purge gas by the fluidic system (16) via the outlet duct (32) before spontaneous closure of the injection pressure regulator (38) when the pressure in the outlet duct (32) between the injection duct (30) and the injection pressure regulator (38) is less than the predetermined threshold pressure P3- spontaneous closure of the purge pressure regulator (50) when the pressure in the purge generation duct (44) between the injection duct and the purge pressure regulator (50) is less than the predetermined intermediate pressure P2.

18. The method according one of claims 16 or 17, wherein the tank (18) includes a filling nozzle (26), the method including, after delivering the gas dose having a predefined volume, connecting a gas delivery head (54) of a gas filling apparatus (14) to the filling nozzle (26) and filling the predefined tank volume V1 of the fluidic gas system (16) at the tank pressure P1.

Images