Fluid product dispensing device comprising a metering valve

Abstract

A fluid product dispensing device comprising a reservoir (1) containing the fluid product and a metering valve (10) including a valve body (11) containing a metering chamber (30), a valve (20) sliding axially within said valve body (11) between a rest position and a dispensing position, to dispense the contents of said metering chamber (30), said valve (20) being actuated towards its rest position by a valve spring (12), said reservoir (1) containing a follower piston (5) and a piston spring (6) which axially actuates said follower piston (5) towards said metering valve (10), said follower piston (5) being adapted to slide axially within said reservoir (1) in a sealed manner after each actuation, to compensate for the volume of each dispensed dose. (See Figure 1 for abbreviations)

Description

Title of the invention: Device for dispensing fluid product comprising a metering valve

[0001] The present invention relates to a fluid product dispensing device comprising a metering valve.

[0002] So-called metering valves, in which each time the valve is actuated, a precise dose of fluid product is dispensed, are well known in the state of the art, and are generally assembled on a reservoir containing the fluid product and a propellant gas used to expel the dose.

[0003] Two main types of metering valves are known.

[0004] So-called retention valves comprise a valve which, in the rest position, partially closes the metering chamber. More precisely, the exterior of the valve cooperates in a sealed manner with the chamber seal of the metering chamber, so that the metering chamber is connected to the reservoir, in this rest position, only via the internal channel of the valve.

[0005] The metering chambers of so-called non-priming valves are only filled just before actual actuation.

[0006] In both cases, the filling of the reservoir with the fluid product to be dispensed is generally done after assembling the metering valve on the reservoir, through said metering valve.

[0007] An important parameter for the proper operation of a retention metering valve is to avoid emptying of the metering chamber during storage between two actuations, called "drain back", for example due to a depression inside the tank which may increase after each actuation.

[0008] Another difficulty concerns the orientation in which the valve must be used to operate reliably. Generally, metering valves must be used in an inverted position, with the reservoir positioned above the valve, to ensure good metering accuracy.

[0009] The present invention aims to provide a fluid product dispensing device which does not reproduce the aforementioned drawbacks.

[0010] The present invention thus aims to provide such a device which limits or even prevents the "drain back" phenomenon.

[0011] The present invention also aims to provide such a device which allows use in all desired orientations.

[0012] The present invention also aims to provide such a device which is simple and inexpensive to manufacture and assemble, and which operates reliably.

[0013] The present invention therefore relates to a device for dispensing a fluid product, comprising a reservoir containing the fluid product and a metering valve comprising a valve body containing a metering chamber, a valve sliding axially in said valve body between a rest position and a dispensing position, to dispense the contents of said metering chamber, said valve being urged towards its rest position by a valve spring, said reservoir containing a follower piston and a piston spring which urges said follower piston axially in the direction of said metering valve, said follower piston being adapted to slide axially in said reservoir in a sealed manner after each actuation, to compensate for the volume of each dose dispensed.

[0014] Advantageously, said follower piston separates said reservoir between an upper reservoir part connected to said metering valve and a lower reservoir part isolated from said metering valve by said follower piston, said follower piston being pushed axially downwards by said fluid product when it is filled in said reservoir, so that said follower piston compresses said piston spring and the air disposed in said lower reservoir part, until a pressure balance is achieved between said upper reservoir part containing said fluid product in liquid form and said lower reservoir part containing the compressed air and said piston spring.

[0015] Advantageously, after each actuation, said piston spring pushes said follower piston axially upwards to compensate for the reduction in volume generated by the dispensing of a dose of fluid product, without substantial modification of the pressure in said upper part of the reservoir, so that said fluid product always remains in liquid form.

[0016] Advantageously, said piston spring exerts a pressure adapted to compensate for each reduction in volume after each actuation, but without exerting a pressure on said follower piston likely to hinder the filling of said reservoir with said fluid product.

[0017] The fluid product may be a pharmaceutical, cosmetic or perfumery product.

[0018] Advantageously, said fluid product comprises a liquid formulation consisting of one or more active ingredient(s) in suspension and / or in solution in a liquefied propellant gas.

[0019] Advantageously, said propellant gas comprises an HFA gas, such as HFA 134a and / or HFA 227 and / or HFA-152a.

[0020] Alternatively, said propellant gas comprises HFO1234ze.

[0021] These and other features and advantages of the present invention will become more clearly apparent from the following detailed description thereof, given with reference to the accompanying drawings, given as non-limiting examples, and in which

[0022] [Fig.l] [Fig.l] is a schematic cross-sectional view of a fluid product dispensing device, before filling the reservoir with the fluid product,

[0023] [Fig.2] [Fig.2] is a view similar to that of [Fig.l], during filling from the tank with the fluid product, and

[0024] [Fig.3] [Fig.3] is a view similar to that of [Fig.2], in the resting position after several actuations.

[0025] In the following description, the terms "top", "bottom", "upper" and "lower" refer to the upright position shown in the figures, and the terms "axial" and "radial" refer to the longitudinal central axis of the device.

[0026] The device shown in the figures comprises a reservoir 1 containing the fluid product, and a metering valve 10. This metering valve 10 is assembled on the reservoir 1, preferably by means of a fixing element 2, which can be a crimping, screwing or snap-on cap, and advantageously with the interposition of a neck seal 3. Optionally, a ring 4 can be assembled around the body 11 of the metering valve 10, in particular to reduce the dead volume in the inverted position and to limit the contact of the fluid product with the neck seal 3. This ring 4 can be of any shape, and the example in the figures is not limiting. Generally speaking, the reservoir 1 contains the fluid product and the propellant gas, in particular a liquid formulation consisting of one or more active ingredient(s) in suspension and / or in solution in a liquefied propellant gas, as well as possibly excipients.The propellant gas advantageously comprises an HFA gas, for example HFA 134a and / or HFA 227. Preferably the propellant gas comprises HFA-152a. Alternatively, other gases which are not harmful to the environment, such as HFO1234ze, may be used.

[0027] The metering valve 10 comprises a valve body 11 extending along a longitudinal central axis. Inside said valve body 10, a valve 20 slides between a rest position, which is that shown in [Fig. 3], and a dispensing position in which the valve 20 is pressed inside the valve body 11. [Fig. 2] shows the valve in the dispensing position when filling the reservoir 1 with the fluid product, filling carried out through the metering valve 10 with the valve 20 actuated.

[0028] The valve 20 is biased towards its rest position by a valve spring 12, which is arranged in the valve body 11 and which cooperates on the one hand with this valve body 11, and on the other hand with the valve 20, preferably with a radial collar 21 of the valve 20. A metering chamber 30 is defined inside the valve body 11, said valve 20 sliding inside said metering chamber 30 to allow the contents thereof to be dispensed when the metering valve is actuated.

[0029] In a known manner, the valve 20 can be made in two parts, namely an upper part (also called valve top) and a lower part (also called valve bottom).

[0030] The metering chamber 30 is preferably defined between two annular seals, a valve seal 31 and a chamber seal 32, in a well-known manner.

[0031] [Fig. 3] shows the metering valve in the upright storage position, i.e. the position in which the metering chamber 30 is arranged above the reservoir 1.

[0032] According to the invention, the reservoir 1 contains a follower piston 5 and a piston spring 6 which biases the follower piston 5 axially upwards towards said metering valve 10. The follower piston 5 is adapted to slide axially in the reservoir 1 in a sealed manner after each actuation, to compensate for the volume of each dose dispensed.

[0033] The insertion of the follower piston 5 into the reservoir can for example be carried out through an open bottom of the reservoir closed, after insertion, by fixing a suitable closing element. Alternatively, this insertion could also be carried out through an open top of the reservoir followed by the fixing of a portion of the reservoir neck.

[0034] Advantageously, the piston spring 6 exerts a low pressure, sufficient to compensate for each reduction in fluid product after each actuation, but without exerting too much pressure on the follower piston 5, which could prevent or complicate the filling of the reservoir 1. The choice of the piston spring 6 and its properties therefore depends on the parameters of the device, such as the dimensions of the reservoir 1, the volume of each dose, the type of formulation, the pressure of the propellant gas, etc.

[0035] Before filling the reservoir 1 with the fluid product, the follower piston 5 is therefore pushed by the piston spring 6 close to the metering valve 10, as visible in [Fig.l].

[0036] During filling, the fluid product pushes the follower piston 5 axially downwards, compressing the piston spring 6 and the air disposed between the follower piston 5 and the bottom of the reservoir 1, until a pressure balance is achieved between the upper part 7 of the reservoir containing the fluid product in liquid form and the lower part 8 of the reservoir containing the compressed air and the piston spring 6. This end-of-filling position is shown in [Fig.2].

[0037] After each actuation, following the dispensing of a dose of fluid product from the reservoir, the volume of the upper part 7 decreases, and the piston spring 6 pushes the follower piston 5 axially upwards to compensate for this decrease in volume without substantial modification of the pressure in the upper part 7 of the reservoir. Thus, the fluid product always remains in liquid form, which eliminates or at least greatly reduces the risks of "drain back".

[0038] Another advantage of this implementation is the ability to operate the valve in any orientation, since the regulation of the volume and pressure in the part upper 7 of the reservoir by the follower piston 5 and its piston spring 6 not only prevents "drain back" but also ensures good filling of the dosing chamber 30 after each actuation.

[0039] Although the present invention has been described with reference to a particular embodiment thereof, it is understood that it is not limited by the example shown. On the contrary, those skilled in the art can make any useful modifications thereto without departing from the scope of the present invention as defined by the appended claims.

Claims

Claims

1. A device for dispensing a fluid product, comprising a reservoir (1) containing the fluid product and a metering valve (10) comprising a valve body (11) containing a metering chamber (30), a valve (20) sliding axially in said valve body (11) between a rest position and a dispensing position, for dispensing the contents of said metering chamber (30), said valve (20) being biased towards its rest position by a valve spring (12), said fluid product comprising a liquid formulation consisting of one or more active ingredient(s) in suspension and / or in solution in a liquefied propellant gas, said reservoir (1) containing a follower piston (5) which separates said reservoir (1) between an upper reservoir part (7) connected to said metering valve (10) and a lower reservoir part (8) isolated from said metering valve (10) by said follower piston (5),characterized in that said lower part (8) of the reservoir (1) contains a piston spring (6) which biases said follower piston (5) axially towards said metering valve (10), said follower piston (5) being adapted to slide axially in said reservoir (1) in a sealed manner after each actuation, to compensate for the volume of each dose dispensed, said follower piston (5) being pushed axially downwards by said fluid product when it is filled in said reservoir (1), so that said follower piston (5) compresses said piston spring (6) and the air disposed in said lower part (8) of the reservoir, until a pressure balance is achieved between said upper part (7) of the reservoir containing said fluid product in liquid form and said lower part (8) of the reservoir containing the compressed air and said piston spring (6).,

2. Device according to claim 1, wherein, after each actuation, said piston spring (6) pushes said follower piston (5) axially upwards to compensate for the decrease in volume generated by the dispensing of a dose of fluid product, without substantial modification of the pressure in said upper part (7) of the reservoir, so that said fluid product always remains in liquid form.

3. Device according to any one of the preceding claims, wherein said piston spring (6) exerts a pressure adapted to compensate for each decrease in volume after each actuation, but without exerting pressure on said follower piston (5) likely to hinder the filling of said reservoir (1) with said fluid product.

4. A device according to any preceding claim, wherein said propellant gas comprises an HFA gas, such as HFA 134a and / or HFA 227 and / or HFA-152a.

5. A device according to any one of claims 1 to 3, wherein said propellant gas comprises HFO1234ze. * * *

Images