Patent Grant
7748647
The present application claims priority of French patent application No. 06 06259 filed on Jul. 10, 2006 and of French patent application No. 07 00485 filed on Jan. 24, 2007, the content of which is incorporated herein by reference.
The present invention relates to a spraying device and a use for this device.
More particularly, the invention relates to a manual spraying device comprising:
Document U.S. Pat. No. 6,145,712 describes an example of such a spraying device, wherein the front face of the spray nozzle has a single central hole.
In spraying devices of this type, the spray nozzles, which are conventionally mounted on pumps or on spray valves, have the disadvantage of bringing about a large dispersion of the diameter of the droplets of the sprayed fluid product.
Indeed, in spray nozzles of a device of this type, the fluid product is split up into fine droplets by a dynamic phenomenon that is particularly difficult to control, generally consisting of creating a vortex inside the inner chamber of the nozzle and of splitting up the fluid product into fine droplets as it leaves at a very high velocity through the central hole.
As an example, it has been possible to measure that, for a spray nozzle of the aforementioned type, of which the inner chamber receives an alcoholic solution under a pressure of 5 bar from a manual pump or a valve, and for a central hole of the nozzle having a diameter of 0.3 mm, the sprayed product consists of droplets having diameters of between 5 μm and 300 μm.
This dispersion can prove to be undesirable when it is desired to spray droplets with substantially uniform sizes. For example, it may be desired to spray droplets with a small size for the inhalation of medicinal treatments of the bronchi, or furthermore, it may be desired to spray larger droplets for cosmetic or perfumery applications, so that the droplets penetrate as little as possible into the bronchi of the user.
Moreover, droplets with very different sizes also follow very different trajectories, which is harm for the controlled application of the sprayed product. For example, when spraying a perfume onto the skin of a user, droplets that are too large can fall on the clothes of the user instead of being projected onto the skin, with the risk of producing indelible spots.
The object of the present invention is in particular to overcome these disadvantages.
To this end, the invention provides a spraying device of the aforementioned type wherein the front wall has a plurality of calibrated holes, each having a diameter of between 1 and 100 μm, the diameter of each hole not differing by more than 20% from a mean of the diameters of the various holes.
It will be noted that the term “diameter” does not necessarily imply that this cross section is circular. Thus, the holes of the front face could, where appropriate, have a polygonal cross section, for example a square cross section, without departing from the scope of the present invention. In this case, the aforementioned diameter will be the equivalent diameter of the hole, namely the diameter of a circular hole having a cross section with the same area as the polygonal hole. If the holes do not have a constant cross section over their length, the diameter in question is the diameter of the minimum cross section of the holes.
By virtue of the arrangements described above, the size of the droplets sprayed by the spraying device are controlled and good uniformity of this size of the droplets is ensured.
In addition, the aforementioned devices also make it possible to be independent at least partially of the pressure differences with which the fluid product is fed into the inner chamber of the spray nozzle, since experiments have shown that the size of droplets obtained by means of the present invention depends very little on this pressure (the pressure differences in question can come for example from differences in the actuating force of a user if the fluid product is fed by means of a manual pump or furthermore, when the fluid product is fed by means of a valve from a reservoir of the product under pressure, the pressure differences in question can come from the fact that the reservoir has already been partially emptied by previous uses of the spraying device).
In addition, the invention aims to improve control over the shape of the aerosol obtained leaving the spray nozzle while enabling the calibrated holes to be made simply.
To this end, in an embodiment that is complementary to, or independent of the embodiment previously defined, the front wall can be elastically deformable between a rest state, in which said front wall is flat, and an actuating state when the fluid product under pressure is transferred into the inner chamber, in which said front wall has an outwardly directed convexity.
Thus, in the rest state, the holes can be made in a simple manner in the flat front wall, it being possible for each hole to have an axis that extends in a plane parallel to a central axis perpendicular to the front wall. In the actuating state, when the fluid product is sprayed, the axes of the holes move way from the central axis so as to have an outwards divergence and the fluid product can be sprayed in the form of an aerosol having a high cone angle.
In various embodiments of the spraying device according to the invention, it is moreover possible for one and/or another of the following devices to be made use of:
In addition, the invention aims to improve control over the distribution of droplets and the form of the aerosol.
To this end, independently of, or complementary to the embodiment previously defined, the holes of the front wall are distributed about a centre, each hole extends along an axis inclined with respect to the normal to said front wall in the region of said hole, said axis and said normal defining a plane substantially tangential to a circle centred on said central point and passing by the hole, the axes of all the holes having an inclination with respect to the corresponding normal, and said axes of all the holes being inclined in the same angular direction about said central point so as to generate a swirling aerosol when the fluid product is sprayed by said nozzle.
On account of the swirling trajectory of the droplets, the aerosol can have, in the vicinity of the spray nozzle, a substantially conical first part having a high cone angle and a second part substantially symmetrical with respect to the central axis of the nozzle.
In various embodiments of the spraying device according to the invention, it is possible in addition to resort to one and/or another of the following arrangements:
In addition, the object of the invention is also a use for a spraying device as defined above, for spraying a non-gaseous fluid product.
In various embodiments of this use, it is possible in addition to resort to one and/or another of the following arrangements:
Other features and advantages of the invention will become apparent during the following description of three of these embodiments, given by way of non-limiting examples, in relation to the appended drawings.
In the various figures, the same references denote identical or similar elements.
The spraying device 1 additionally includes a dispensing device 4 that is fixed in a known manner to a neck 5 of the reservoir 3 at the upper end of said reservoir.
The dispensing device 4 can for example be a manual spraying pump or furthermore a spraying valve, in which case the reservoir 3 is under pressure.
In all cases, the dispensing device 4 comprises a downwardly directed inlet 6 for the fluid product, which communicates with the bottom of the reservoir 3 via a dip tube 7, and a hollow actuating rod 8 which projects upwards. A push-button 9 is fitted to the upper end of the actuating rod 8, and serves both to actuate the dispensing device 4 and as an outlet for the sprayed fluid product, which outlet is made through the actuating rod 8 along the arrow 10 shown in
It will be noted that the dispensing device shown in
As shown in
The push-button 9 comprises a substantially horizontal upper wall 11 and a substantially cylindrical and vertical skirt 12, which extends from the periphery of the upper wall 11.
In addition, the push-button 9 also includes a central well 13 that extends vertically downwards from the upper wall 11, to the centre of the side wall 12. The upper end of the actuating rod 8 is fitted into the central well 13.
A lateral passage 14 is provided at the upper end of the central well 13 and communicates with a housing for receiving the nozzle 15 of a substantially cylindrical shape, extending substantially horizontally along a central axis X and emerging towards the outside of the push-button 9.
As shown in
In a known manner, the side wall 18 of the spray nozzle 16 can have, at its end opposite the front wall 17, an annular lip 19 which projects radially outwards and which penetrates the material of the push-button 9 in order to anchor the spray nozzle 16 into the nozzle housing 15.
The spray nozzle 16 delimits, with the push-button 9, an inner chamber 20 that communicates with the aforementioned passage 14 and that receives the fluid product to be sprayed when the dispensing device 4 is actuated. Possibly, as can be seen in
As shown in greater detail in
More generally, the diameter of each hole 22 does not differ from the mean value of the diameters of the various holes 22 by more than 20% and advantageously, the diameter of each hole 22 does not differ from said mean value by more than 10%.
The holes 22 can be of a substantially cylindrical shape with circular cross section but they could, where appropriate, have a polygonal cross section, for example a square cross section, in which case the aforementioned diameter would be the equivalent diameter of the hole, namely the diameter of a circular hole having a cross section of the same area as the polygonal hole.
The diameter of the holes 22 can be chosen according to the fluid to be sprayed and for example:
The front wall 17 can have a domed form with an inwardly directed concavity, as in the example shown in
In addition, the front wall 17 can have a thickness e generally between 0.08 and 1.5 mm, in particular between 0.2 and 0.4 mm.
The holes 22 can have a constant cross section, as in the example shown, but the holes 22 could, where appropriate, have parts flared inwards and/or outwards, in which case the length of the holes 22 to be taken into account would be the length in which these holes have a constant cross section and the diameter to be taken into account would be the diameter of the minimum cross section. The length of the holes 22, in their part with a constant cross section, generally is between 0.08 and 0.5 mm, advantageously between 0.08 and 0.3 mm and even more advantageously between 0.08 and 0.2 mm, in particular equal to approximately 0.1 mm.
As shown in
In the second embodiment shown in
In particular, in the rest state, the front wall 17b extends in a plane perpendicular to the central axis X. Also, in the actuating state, the front wall 17b has an outwardly directed convexity so that, for example, it has the form of a spherical cap.
As shown in
In
The elastically deformable front wall 17b according to the second embodiment can be made complementary to or independent of the embodiment previously described in which all the holes 22 are substantially of the same diameter, between 1 and 100 μm, and the diameter of each hole 22 advantageously does not differ from the mean value of the diameters of the various holes 22 by more than 20%.
In the variant shown in
As shown in
The third embodiment of
In a variant shown in
For example, the front wall 17a can be made of a material chosen from silicon, glass, metals and their alloys, ceramics or polymers, while the side wall 18 is made of a plastic as in the previous example, it being possible that said side wall 18 to be overmoulded over the periphery of the front wall 17a.
In the embodiment of
In addition, in another embodiment, the front wall 17a can be deformable. For example, the front wall 17a can be made in the form of a complex including at least one polymer layer and possibly a layer of metallic material. The complex can have a thickness of between 0.025 and 0.120 mm.
As non-limiting examples, the complex can comprise:
In the fourth embodiment of the invention, shown in
On account of the fact that the holes 22 are all inclined in the same angular direction 24 (
The aerosol A has a first part b1, in the vicinity of the spray nozzle, in which the liquid droplets are impelled forwards at a high velocity and which is substantially conical, having a relatively high cone angle α of the order of 20° or more.
Moreover, the aerosol A has a second part p2 forming a cloud in which the liquid droplets have a forward velocity less than in the first part p1. By virtue of the swirling movement of the liquid droplets, the second part b2 of the aerosol remains relatively symmetrical with respect to the axis X.
In this embodiment, with a front wall 17 having about a hundred holes 22 with a diameter of 3 μm provided in a wall 17 of thickness 0.3 mm, with an inclination of the holes of the order of 30° and with a pressure of an alcoholic liquid of the order of 0.5 bar inside the spray nozzle, spraying is obtained of an aerosol consisting of droplets with a diameter of 5 μm to 7 μm.
As a variant, it is possible to provide that the front wall 17 is elastically deformable. In the rest state, the calibrated holes 22 can then be made in a simple manner with an axis X2 that extends in a plane parallel to the central axis X as the spray nozzle 16. The divergence of the axis X2 of the calibrated holes 22 can be obtained when the push-button is actuated in order to increase the cone angle α of the first part of the aerosol A.
| Number | Date | Country | Kind |
|---|---|---|---|
| 06 06259 | Jul 2006 | FR | national |
| 07 00485 | Jan 2007 | FR | national |
| Number | Name | Date | Kind |
|---|---|---|---|
| 5868003 | Simas et al. | Feb 1999 | A |
| 6145712 | Benoist | Nov 2000 | A |
| 6732943 | Srinivasan | May 2004 | B2 |
| 20060213408 | Christ | Sep 2006 | A1 |
| Number | Date | Country |
|---|---|---|
| 202 12 798 | Nov 2002 | DE |
| 0 891 945 | Jan 1999 | EP |
| 1 621 253 | Feb 2006 | EP |
| 169 83 99 | Sep 2006 | EP |
| 2002-186882 | Jul 2002 | JP |
| WO 03072261 | Sep 2003 | WO |
| Number | Date | Country | |
|---|---|---|---|
| 20080006719 A1 | Jan 2008 | US |
