DOSING VALVE WITH IMPROVED DOSING CHAMBER

Description

[0001] The present invention relates to a dosing valve for a fluid product distribution device.

[0002] So-called metering valves, in which a precise dose of fluid product is distributed with each actuation of the valve, are well known in the prior art, and are generally assembled on a tank containing the fluid product and a propellant gas used to expel the dose.

[0003] There are two main types of metering valves. Retaining valves have a valve that, in its rest position, partially closes the metering chamber. More precisely, the exterior of the valve seals tightly against the metering chamber's seal, so that in this rest position, the metering chamber is connected to the reservoir only via the valve's internal channel. Self-priming valves have a metering chamber that, in its rest position, is open to the reservoir and fills upon activation, when the user returns the device to its reversed operating position.

[0004] Depending on the product being dispensed and / or the patient, the dose delivered with each actuation can vary, for example, from 25 to 75 µl. One solution is to use a larger or smaller insert in the dosing chamber, depending on the desired volume. However, increasing the volume above a certain value, typically 75 µl, is difficult without modifying the dimensions of the valve body, which would require changes to the manufacturing and assembly machinery and therefore incur significant costs.

[0005] Documents EP1618049, WO2021156580, EP0061973, WO2014096657, FR3042785 and FR2860502 describe prior art devices.

[0006] The present invention aims to provide a metering valve that does not reproduce the aforementioned disadvantages.

[0007] The present invention thus aims to provide a dosing valve which makes it possible to increase the volume of the dosing chamber without modifying the valve body.

[0008] The present invention also aims to provide a metering valve that is simple and inexpensive to manufacture and assemble, and of reliable operation.

[0009] The present invention therefore relates to a metering valve for distributing a fluid product, comprising a valve body containing a metering chamber, said metering chamber being defined by a chamber insert and two annular seals, a valve seal and a chamber seal, said chamber insert having a cylindrical wall, an upper edge cooperating with said valve seal and a lower edge cooperating with said chamber seal, a valve sliding axially in said valve body between a rest position and a dispensing position, to selectively dispense the contents of said metering chamber, said valve being forced towards its rest position by a spring cooperating on the one hand with said valve body and on the other hand with said valve, said cylindrical wall of said chamber insert having at least one opening connecting said metering chamber to an external volume disposed outside said chamber insert,between said valve body and said cylindrical wall.

[0010] Advantageously, said upper edge of said chamber insert extends radially inwards by means of an upper flange which increases the contact area with said valve seal, said contact area being always the same, regardless of the width of said cylindrical wall.

[0011] Advantageously, said lower edge of said chamber insert extends radially inwards by a lower flange which increases the contact area with said chamber seal, said contact area always being the same, regardless of the width of said cylindrical wall.

[0012] Advantageously, the volume of said dosing chamber is modifiable between 25 and 100 µl, without modification of said valve body, by adapting the thickness of said cylindrical wall and / or the number, shape and / or dimensions of said openings.

[0013] According to a first advantageous variant, the cylindrical wall of the chamber insert has a single opening.

[0014] According to a second advantageous variant, the cylindrical wall of the chamber insert has two diametrically opposed openings.

[0015] According to a third advantageous variant, said cylindrical wall of said chamber insert has a plurality of openings distributed around the periphery of said cylindrical wall.

[0016] The present invention also relates to a fluid product distribution device comprising a metering valve as defined above, said valve being mounted on a reservoir containing fluid product and a propellant gas.

[0017] Advantageously, said propellant gas comprises one or more HFA gases, such as HFA-134a and / or HFA-227 and / or HFA-152a.

[0018] Alternatively, said propellant gas includes HF01234ze.

[0019] These and other features and advantages of the present invention will become more apparent from the following detailed description thereof, made with reference to the accompanying drawings, given by way of non-limiting examples, and on which there figure 1 is a schematic cross-sectional view of a metering valve according to the prior art, in the valve's rest position, in the valve's upright storage position, the figure 2 is a view similar to that of the figure 1 showing a metering valve according to an advantageous embodiment of the invention, during valve actuation, the figure 3 is a detailed perspective view of a dosing chamber insert according to the prior art, and the figures 4 à 8 are detailed perspective views of different embodiments of the dosing chamber insert according to the invention.

[0020] In the description below, the terms "top", "bottom", "lower", "upper" and "vertical" refer to the upright position shown on the figures 1 et 2 and the terms "axial" and "radial" refer to the longitudinal central axis of the valve.

[0021] There figure 1 represents a prior art metering valve at rest, in its upright storage position, that is, the position in which the valve is arranged above the reservoir. figure 2 represents a metering valve according to an advantageous embodiment of the invention, during actuation. It should be noted that the valve of the figure 2 is also shown in an upright position, whereas the normal operating position of such a valve is an inverted position, with the valve positioned under the tank.

[0022] This valve is intended to be mounted on a tank (not shown) containing fluid and a propellant gas, preferably by means of a fastening element 5, which may be a crimp, screw, or snap-on cap, and advantageously with the interposition of a neck seal 6. Optionally, a ring 4 may be mounted around the valve body 10, in particular to reduce the dead volume in the inverted position and to limit the contact of the fluid with the neck seal 6. This ring 4 may be of any shape, and the example of figures 1 et 2 This list is not exhaustive. Generally, the tank contains the fluid product and the propellant gas, in particular a formulation consisting of one or more active ingredient(s) in suspension and / or solution in a liquefied propellant gas, and possibly excipients. The propellant gas preferably comprises one or more HFA gases, such as HFA-134a and / or HFA-227 and / or HFA-152a, with or without ethanol. Alternatively, other non-harmful gases, such as HFO1234ze, may be used.

[0023] The metering valve shown on the figures 1 et 2 It comprises a valve body 10 extending along a central longitudinal axis and containing a metering chamber 20. This metering chamber 20 is defined between two annular seals, a valve seal 21 and a chamber seal 22, in a well-known manner. This metering chamber 20 is filled before or after each actuation with a dose of fluid product from the reservoir.

[0024] Inside said valve body 10, a valve 30 slides between a rest position, which is that shown on the figure 1 and a distribution position, in which the valve 30 is pushed into the valve body 10. The valve 30 is forced towards its rest position by a spring 8, which is disposed in the valve body 10 and which cooperates on one side with this valve body 10, and on the other side with the valve 30, preferably with a radial collar 320 of the valve 30. The valve 30 slides inside the metering chamber 20 to allow the distribution of the contents of the latter when the valve is actuated.

[0025] The valve body 10 has a cylindrical portion 15 in which the spring 8 is disposed and in which the flange 320 slides between its rest and distribution positions. In the position of figures 1 et 2 This cylindrical portion 15 is the lower part of the valve body. This cylindrical portion 15 has one or more openings, such as slots, extending laterally within said cylindrical portion 15 of the valve body, along a portion of the axial height of the valve body in the direction of the longitudinal central axis. These openings allow the metering chamber 20 to be filled after each actuation, when, in the reversed operating position (with the valve positioned below the reservoir), the valve 30 returns from its dispensing position to its rest position.

[0026] As is known, the valve 30 can be made in two parts, namely an upper part 31 (also called valve top) and a lower part 32 (also called valve bottom).

[0027] The upper part 31 includes a central axial channel 35 provided with an axial outlet 301 and a radial inlet channel 302 which is disposed in the metering chamber 20 when the valve 30 is in the dispensing position. The upper part 31 also includes a radial shoulder 310 which, in the rest position shown in the figure 1 , rests under the valve seal 21, in a known manner.

[0028] In this embodiment, the lower part 32 is assembled inside the upper part 31.

[0029] An internal channel 33 is provided in the valve 30, in particular in the lower part 32, which allows the dosing chamber 20 to be connected to the reservoir, to fill said dosing chamber 20 when, after each actuation of the valve, the valve 30 returns to its rest position under the effect of the spring 8. This filling takes place when the device is still in the reversed position of use, with the valve disposed below the reservoir.

[0030] In the example of the figure 1 When the valve 30 is in its rest position, the metering chamber 20, outside the valve 30, is substantially isolated from the reservoir 1 by the interaction between the lower part 32 of the valve 30 and the chamber seal 22. In this rest position, the metering chamber 20 therefore remains connected to the reservoir only via the internal channel 33. The valve shown in the figures 1 et 2 It is therefore a retention valve. However, the invention is also applicable to other types of valves, in particular priming-free valves.

[0031] The volume of the dosing chamber 20 is defined by means of a chamber insert 40, which is substantially cylindrical in shape.

[0032] There figure 3 illustrates the anterior art valve chamber insert of the figure 1 , and the figures 4 à 8 show several different variants of a chamber insert according to the invention.

[0033] The chamber insert 40 has a cylindrical wall 49 whose radial thickness varies depending on the desired dosing chamber volume. Thus, the volume of the dosing chamber 20 can be modified primarily by adjusting the thickness of this cylindrical wall 49. In the anterior art valve, this volume can vary between 25 and 75 µl.

[0034] The valve seal 21 rests on the upper edge 41 of the chamber insert 40, and the chamber seal 22 is in contact with the lower edge 43 of the chamber insert 40. The upper edge 41 advantageously has a projecting profile 42 which penetrates the valve seal 21, and the lower edge 43 advantageously has a projecting profile 44 which penetrates the chamber seal 22.

[0035] Advantageously, the lower edge 43 extends radially inwards via a lower flange 46, which increases the contact area with the chamber seal 22. In this advantageous embodiment, the lower edge 43 and the lower flange 46 together form a contact area with the chamber seal 22 that is always identical, regardless of the width of the cylindrical wall 49. The positioning of the chamber seal 22 on the chamber insert 40 is therefore always identical, regardless of the width of the cylindrical wall 49 and thus the volume of the dosing chamber 20. Consequently, the behavior of the chamber seal 22 will always be the same, regardless of the volume of the dosing chamber 20.

[0036] Advantageously, the upper edge 41 extends radially inwards via an upper flange 47, which increases the contact area with the valve seal 21. In this advantageous embodiment, the upper edge 41 and the upper flange 47 together form a contact area with the valve seal 21 that is always identical, regardless of the width of the cylindrical wall 49. The positioning of the valve seal 21 on the chamber insert 40 is therefore always identical, regardless of the width of the cylindrical wall 49 and thus the volume of the metering chamber 20. Consequently, the behavior of the valve seal 21 will always be the same, regardless of the volume of the metering chamber 20.

[0037] With the 40 chamber insert of the prior art shown on the figures 1 And 3The volume of the dosing chamber 20 is defined exclusively within the chamber insert 40. Indeed, due to the closed cylindrical wall 49 and the two seals 21 and 22, the external volume located outside the chamber insert 40, between the valve body 10 and the cylindrical wall 49, is completely isolated from the dosing chamber. With a standard valve body as shown in the figure 1 This external volume can represent up to approximately 5 µl, which, for a dosing chamber volume of 25 to 75 µl, is not negligible. Even if it is not visible on the figure 1 , this external volume always exists between the valve body 10 and the cylindrical wall 49 of the chamber insert 40, due to the clearance required between these two parts to allow the insertion of the chamber insert 40 into the valve body 10.

[0038] According to the invention, the cylindrical wall 49 of the chamber insert 40 has at least one opening 48 connecting said dosing chamber 20 to said external volume. Thus, the volume of the dosing chamber 20 is increased, on the one hand, by the addition of said external volume and, on the other hand, by the volume represented by each opening 48 in the cylindrical wall 49. Thus, without modifications to the valve body 10, the dosing chamber 20 with a chamber insert 40 according to the invention can have a volume greater than 75 µl, for example, 85 µl. Volumes up to approximately 100 µl are possible, depending on the number and dimensions of the openings 48 in the cylindrical wall 49.

[0039] Another advantage of the invention is that by including the external volume in the dosing chamber, there is no longer a pressure difference between the inside and outside of the cylindrical wall 49 of the chamber insert 40. In the prior art example of the figures 1 And 3Such a pressure difference could reach approximately 3 to 6 bar, depending on the nature of the propellant gas used, with a pressure of 1 bar in the external volume and a pressure of 4 to 7 bar in the metering chamber. This pressure difference can, in some cases, cause deformation of the cylindrical wall 49 and consequently an undesirable change in the volume of the metering chamber 20.

[0040] THE figures 4 à 8 show several different variants of a chamber insert 40 according to the invention.

[0041] In the example of the figure 4 , there is a single opening 48, advantageously cylindrical, which passes through the cylindrical wall 49 of the chamber insert, to connect the dosing chamber 20 with the external volume existing between the valve body 10 and the cylindrical wall 49 of the chamber insert 40.

[0042] In the example of the figure 6 , there are two diametrically opposed openings 48. In this example, the thickness of the cylindrical wall 49 is reduced, so that the upper flange 47 and lower flange 46 also extend radially outwards from the cylindrical wall 49.

[0043] The example of the figure 5 is similar to that of the figure 6 except that the chamber insert does not have a top flange 47.

[0044] In the example of the figure 7 , there is a plurality of openings 48 formed by axial slits distributed around the periphery and extending over part of the height of the cylindrical wall 49 from the upper edge 41.

[0045] In the example of the figure 8 , there are a plurality of openings 48 formed by windows distributed around the periphery and extending over part of the height of the cylindrical wall 49 from the lower edge 43.

[0046] Of course, in all the examples above, the number, shape and dimensions of each opening 48 can be arbitrary.

[0047] Although the present invention has been described with reference to several particular embodiments thereof, it is understood that it is not limited by the examples shown. On the contrary, a person skilled in the art may make any useful modifications to it without departing from the scope of the present invention as defined by the attached claims.

Claims

1. Metering valve for dispensing a fluid product, comprising a valve body (10) containing a metering chamber (20), said metering chamber (20) being defined by a chamber insert (40) and two annular rings, a valve stem seal (21) and a chamber seal (22), said chamber insert (40) comprising a cylindrical wall (49), an upper edge (41) that cooperates with said valve stem seal (21) and a lower edge (43) that cooperates with said chamber seal (22), a valve stem (30) sliding axially in said valve body (10) between a rest position and a dispensing position, to selectively dispense the contents of said metering chamber (20), said valve stem (30) being urged towards its rest position by a spring (8) that cooperates, on the one hand, with said valve body (10) and on the other hand with said valve stem (30), characterised in that said cylindrical wall (49) of said chamber insert (40) comprises at least one opening (48) connecting said metering chamber (20) to an external volume arranged outside said chamber insert (40), between said valve body (10) and said cylindrical wall (49).

2. Valve according to claim 1, wherein said upper edge (41) of said chamber insert (40) extends radially inwards by a upper flange(47) which increases the contact surface with said valve stem seal (21), said contact surface always being the same, whatever the width of said cylindrical wall (49).

3. Valve according to claim 1 or 2, wherein said lower edge (43) of said chamber insert (40) extends radially inwards by a lower flange(46) which increases the contact surface with said chamber seal (22), said contact surface always being the same, whatever the width of said cylindrical wall (49).

4. The valve according to any one of the preceding claims, wherein the volume of said metering chamber (20) is modifiable between 25 and 100µI, without modification of said valve body (10), by adapting the thickness of said cylindrical wall (49) and / or the number, shape and / or dimensions of said openings (48).

5. Valve according to any one of the preceding claims, wherein said cylindrical wall (49) of said chamber insert (40) comprises a single opening (48).

6. Valve according to any one of claims 1 to 4, wherein said cylindrical wall (49) of said chamber insert (40) comprises two diametrically opposed openings (48).

7. Valve according to any one of claims 1 to 4, wherein said cylindrical wall (49) of said chamber insert (40) comprises a plurality of openings (48) distributed over the periphery of said cylindrical wall (49).

8. Device for dispensing a fluid product, characterised in that it comprises a metering valve according to any one of the preceding claims, said valve being mounted on a reservoir containing the fluid product and a propellant.

9. The device according to the 8 claims, wherein said propellant comprises HFA gases, such as HFA-134a and / or HFA-227 and / or HFA-152a.

10. Device according to claim 8, wherein said propellant comprises HFO1234ze.