The present invention relates to a metering valve and to a fluid dispenser device including such a valve.
“Metering valves” in which an accurate dose of fluid is dispensed each time the valve is actuated are well known in the prior art, and they are generally assembled on a reservoir containing the fluid and a propellant gas that is used to expel the dose.
Two main types of metering valve are known.
Retention valves include a valve member that, in the rest position, closes the metering chamber in part. More precisely, the outside of the valve member co-operates in leaktight manner with the chamber gasket of the metering chamber such that, in the rest position, the metering chamber is connected to the reservoir only via the internal channel of the valve member.
Metering chambers of “primeless” valves fill only just before actuation proper.
In both configurations, the reservoir is generally filled with the fluid that is to be dispensed after the metering valve has been assembled on the reservoir, and it is filled through said metering valve.
An important parameter for a metering valve is the content of fine particles dispensed on each actuation. Specifically, such fine particles are particularly effective from a therapeutic point of view.
Another important parameter is the time taken to fill the reservoir through the metering valve, which filling time should not be too long, so as not to slow down the manufacturing process.
Documents WO 2014/199182, US 2007 272767, and US 2015 023883 describe prior-art devices.
An object of the present invention is to provide a metering valve that does not have the above-mentioned drawbacks.
An object of the present invention is thus to provide a metering valve that optimizes the content of fine particles dispensed on each actuation, while guaranteeing a filling speed through said valve that is acceptable.
A particular object of the present invention is to provide a metering valve that is simple and inexpensive to manufacture and to assemble, and that is reliable in operation.
The present invention thus provides a metering valve for dispensing fluid, the metering valve comprising a valve body containing a metering chamber, a valve member slidable axially in said valve body between a rest position and a dispensing position so as to dispense the contents of said metering chamber selectively, said valve member being urged towards its rest position by a spring that co-operates firstly with said valve body and secondly with said valve member, said valve member including a central axial channel that is provided with an axial outlet orifice and with a radial inlet channel that is arranged in said metering chamber when said valve member is in its dispensing position, said radial inlet channel including, in the fluid dispensing direction, an inlet opening and an outlet opening that opens out into said central axial channel, the diameter of said radial inlet channel lying in the range 0.30 millimeters (mm) to 0.40 mm, and is advantageously about 0.35 mm, the diameter of said outlet opening being equal to the diameter of said radial inlet channel, and the diameter of said inlet opening being greater than the diameter of said radial inlet channel.
Advantageously, said radial inlet channel is cylindrical over a major portion of its length, starting from said outlet opening.
Advantageously, the diameter of said inlet opening lies in the range 0.6 mm to 0.8 mm, and is advantageously about 0.7 mm.
Advantageously, the radial depth of said inlet opening is about 0.2 mm.
The present invention also provides a fluid dispenser device comprising a metering valve as defined above, fastened on a reservoir.
These characteristics and advantages and others of the present invention appear more clearly from the following detailed description thereof, given by way of non-limiting examples, and with reference to the accompanying drawings, and in which:
In the following description, the terms “upper”, “lower”, “top”, “bottom”, “vertical”, and “horizontal” refer to the upright position shown in
The metering valve shown in
The valve is for assembling on a reservoir 1 (only the neck of which is shown in diagrammatic manner in
The valve member 30 is urged towards its rest position by a spring 8 that is arranged in the valve body 10 and that co-operates firstly with the valve body 10 and secondly with the valve member 30, preferably with a radial collar 320 of the valve member 30. A metering chamber 20 is defined inside the valve body 10, said valve member 30 sliding inside said metering chamber 20 so as to enable its contents to be dispensed when the valve is actuated.
In conventional manner, the metering chamber 20 is preferably defined between two annular gaskets, namely a valve-member gasket 21, and a chamber gasket 22.
The valve body 10 includes a cylindrical portion 15 in which the spring 8 is arranged, and in which the collar 320 slides between its rest and dispensing positions. In the position in
The valve member 30 includes a central axial channel 35 that is provided with an axial outlet orifice 301 and with a radial inlet channel 302 that is arranged in the metering chamber 20 when the valve member 30 is in its dispensing position. In the fluid dispensing direction, the radial inlet channel 302 includes an inlet opening 3021 and an outlet opening 3022, the outlet opening opening out into said central axial channel 35.
Surprisingly, it has been found that the dimensions of said radial inlet channel 302 have an impact on the quantity of fine particles dispensed in each dose.
The
Thus,
The test in
The tests were performed with a formulation containing a high percentage of ethanol (15 percent by weight (wt %)), an excipient, an active principle (salbutamol sulfate), and HFA 134a as propellant gas. The reservoirs tested were all filled with the same formulation.
Naturally, the smaller the diameter of the radial inlet channel 302, the greater the time taken to fill the reservoir 1 through the valve. However, a filling time that is too long can turn out to be unacceptable.
Consequently, in the invention, the diameter of the radial inlet channel 302 lies in the range 0.30 mm to 0.40 mm, and is advantageously about 0.35 mm. This makes it possible to optimize the amount of fine particles dispensed, without slowing down unacceptably the time taken to fill the reservoir. The therapeutic effectiveness of the fluid dispensed is thus improved.
In the advantageous embodiment shown in the figures, the radial inlet channel 302 is cylindrical over a major portion of its length, starting from said outlet opening 3022 to said inlet opening 3021.
The diameter of said outlet opening 3022 is equal to the diameter of said radial inlet channel 302, while the diameter of said inlet opening 3021 is greater than the diameter of said radial inlet channel 302, in particular lying in the range 0.6 mm to 0.8 mm, and is advantageously about 0.7 mm, while the radial depth of said inlet opening 3021 is advantageously about 0.2 mm. This can be seen in particular in
In known manner, the valve member 30 may be made of two portions, namely an upper portion 31 (also known as a valve-member top) and a lower portion 32 (also known as a valve-member bottom). The upper portion 31 includes said central axial channel 35, said axial outlet orifice 301, and said radial inlet channel 302. In this embodiment, the lower portion 32 is assembled inside the upper portion 31.
An internal channel 33 is provided in the valve member 30, in particular in the bottom portion 32, that makes it possible to connect the metering chamber 20 to the reservoir 1, so as to fill said metering chamber 20 after each actuation of the valve when the valve member 30 returns to its rest position under the effect of the spring 8. Filling is performed when the device is still in its upsidedown working position, with the valve arranged below the reservoir 1.
In the embodiment in
Although the present invention is described above with reference to a particular embodiment thereof, naturally it is not limited by the embodiment shown. On the contrary, any useful modification could be applied thereto by a person skilled in the art, without going beyond the ambit of the present invention, as defined by the accompanying claims.
Number | Date | Country | Kind |
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1754009 | May 2017 | FR | national |
Filing Document | Filing Date | Country | Kind |
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PCT/FR2018/051119 | 5/4/2018 | WO | 00 |