Dispensing head for a liquid product

Description

[0001] The present invention relates to a fluid product dispensing head intended to be associated with a dispensing member such as a pump or a valve. The dispensing head may be integrated into, or mounted on, the dispensing member. The dispensing head may comprise a bearing surface so as to constitute a pusher on which the user presses to actuate the dispensing member. Alternatively, the dispensing head may be devoid of a bearing surface. This type of fluid product dispensing head is frequently used in the fields of perfumery, cosmetics or even pharmacy.

[0002] A classic dispensing head, for example of the pusher type, includes: a support surface on which a user can press with a finger, for example the index finger, an inlet well intended to be connected to an outlet of a dispensing member, such as a pump or a valve, an axial mounting housing in which a spindle extends, defining a side wall and a front wall, and a bucket-shaped nozzle comprising a substantially cylindrical wall, one end of which is closed by a spray wall forming a spray orifice, the nozzle being mounted along an axis X in the axial mounting housing with its cylindrical wall engaged around the spindle and its spray wall in axial abutment against the front wall of the spindle.

[0003] Typically, the inlet well is connected to the axial mounting housing by a single supply duct. On the other hand, it is common to form a swirl system at the spray wall of the nozzle. A swirl system conventionally comprises several tangential swirl channels that open into a swirl chamber centered on the spray orifice of the nozzle. The swirl system is arranged upstream of the spray orifice.

[0004] In document EP1878507A2, several embodiments of a nozzle are described comprising a spray wall pierced with several spray holes of substantially or perfectly identical diameter, of the order of 1 to 100 µm, with a tolerance of 20%. Such a spray wall would generate a spray whose droplet size is relatively homogeneous. In one embodiment of this document, the holes are arranged in concentric circles, with an inclination of the order of 10 to 60 degrees and a tangential orientation, so as to create a swirling spray around the central axis. In another embodiment, the spray wall is planar and the holes are parallel. In yet another embodiment, the wall is curved and the holes are divergent.

[0005] In document EP1698399A1, the spray wall is curved, but the holes were drilled perpendicular to the plane of the wall with a constant section, while the wall was still flat. The curvature of the wall allows the holes to diverge, once the wall is curved. It is not explained in this document how, or at what point, the drilled flat wall is curved.

[0006] In both documents, the holes generate jets of fine droplets, each of which follows its own trajectory until the droplets are dispersed into a cloud. Other known dispensing heads are described in GB 2 466 631 A, WO 93 / 23174 A1, JP S59 206064 A and DE 20 2004 019745 U1.

[0007] The present invention aims to define a dispensing head which uses another principle of droplet dispersion, which does not result solely from the passage of the fluid product through the spray wall.

[0008] To achieve this aim, the present invention proposes a fluid product dispensing head comprising a spray wall defining a central axis and pierced with holes through which the pressurized fluid product passes so as to form jets of fluid product, the holes extending along axes corresponding to the trajectory of the jets of fluid product, at least some of the axes being intersecting, so that the jets of fluid product, which extend along these intersecting axes, meet at at least one collision point.

[0009] Thus, the dispersion of the fluid product also results from the collision of jets, which can be formed by trains of already fine or very fine droplets. The impact of the droplets between them will divide them into even finer droplets.

[0010] As a guide, the holes may be 10 to 500 in number and have a diameter of the order of 1 to 100 µm, advantageously of the order of 5 to 30 µm, and preferably of the order of 5 to 20 µm. The more holes there are, the smaller their diameter must be, and vice versa. The cumulative section of all the holes must be less than 100,000 µm 2< .

[0011] According to the invention, the spray wall defines a normal at each hole, the axes of the holes being coincident with their respective normal. In other words, each hole is perpendicular to the plane of the wall which directly surrounds it. Or, each hole is defined, at the external face of the spray wall, by an annular edge, advantageously circular, which is inscribed in a plane: the axis of the hole being orthogonal to this plane.

[0012] According to another feature of the invention, the spray wall may be profiled, so that it is not entirely flat. There may therefore be one or more flat areas, but there may also be one or more non-flat areas, for example concave or convex, or even conical.

[0013] According to another aspect, the holes may be aligned radially, at least in pairs (of holes), such that the jets from the radially aligned holes meet at a collision point P. Preferably, the axes of these pairs of holes are inscribed in the orthogonal plane which passes through the central axis and their respective normals.

[0014] According to a practical embodiment, the holes may be arranged along concentric circles, which are respectively located at concave and convex areas, convex and flat areas or a single concave area. In other words, one circle may be located at a concave area and the other circle at a flat area, or, one circle may be located at a concave area and the other circle at a convex area, or, both circles may be located in a single concave area. Other arrangements are still conceivable.

[0015] The holes can be oriented so that the collision points together form a ring or focal point. All the holes can converge to a single collision focal point, or separate collision points from pairs of converging holes can together form a focal ring.

[0016] According to the invention, the holes may have different diameters. The holes located closest to the central axis may, for example, have a diameter that is smaller than the holes located furthest from the central axis. Indeed, it has been observed that the droplets resulting from the collision deviate to the side where the jet has a lower speed. And the larger the diameter of the holes, the lower the speed of the droplets. It is therefore advisable to position the larger diameter holes on the outside, furthest from the central axis, when seeking to open the spray angle. The opposite is also possible, particularly when a restricted spray angle is desired.

[0017] According to a preferred embodiment, the holes are arranged along concentric circles, namely a small inner circle and a large outer circle, all the holes in the small inner circle having the same diameter and all the holes in the large outer circle having the same diameter, the holes in the small inner circle having a smaller diameter than the holes in the large outer circle. This results in an open spray with collision points arranged in a ring. The droplets resulting from the collisions will mainly be projected outwards relative to the central axis.

[0018] According to a practical embodiment which is conventional in the fields of perfumery, cosmetics and sometimes pharmacy, the dispensing head comprises: a mounting housing, a nozzle comprising a sleeve engaged in the mounting housing, the spray wall being integral with the sleeve.

[0019] The head may be in the form of a conventional pusher with an upper bearing surface, on which a user can press with a finger, for example the index finger. The axial housing then opens laterally. The nozzle may be force-fitted and / or snapped and / or harpooned into the axial housing.

[0020] The invention also defines a method of manufacturing a spray wall as defined above, comprising: drill a flat strip of parallel perpendicular holes, stamp this drilled flat strip to profile it so as to bring the axes of the holes (O1, O2) to intersect.

[0021] With holes arranged in concentric circles, it will be sufficient to form an angle in the strip of less than 180 degrees to rotate the axes of the holes of one circle towards the axes of the holes of the other circle so that they intersect. The smaller the angle, the closer the collision points are to the holes. An axial distance of around 1 to 5 mm gives good results.

[0022] The spirit of the invention lies in the fact of carrying out a plurality of jet collisions with a spray wall pierced with 10 to 500 holes of 1 to 100 µm. A radial arrangement of the holes, in particular in concentric circles, is particularly advantageous. Obtaining a single focal point is preferred, because the probability of collision is optimized.

[0023] The invention will now be more fully described with reference to the attached drawings, giving, by way of non-limiting examples, several embodiments of the invention.

[0024] In the figures: There figure 1 is a perspective view of a pump equipped with a dispensing head according to the invention, The figure 2 is a greatly enlarged sectional view of the nozzle of the distribution head of the figure 1 , There figure 3 is a front view of the nozzle of the figure 2 , THE Figures 4 and 5 are views similar to those of the Figures 2 and 3 for a second embodiment of a nozzle of the invention, and The figures 6 and 7 are views similar to those of the Figures 2 and 3 for a third embodiment of a nozzle of the invention.

[0025] On the figure 1 , the dispensing head T is mounted on a dispensing member D, such as a pump or a valve, which has a completely conventional design in the fields of perfumery or pharmacy. This dispensing member D is actuated by the user by pressing axially with a finger, generally the index finger, on the head T.

[0026] The dispensing member D is mounted on a fluid product reservoir by means of a fixing ring F: this thus constitutes a fluid product dispenser, which is entirely manual, without energy input, in particular electrical.

[0027] In the case of a pump, the normal pressure generated by this axial support on the fluid product inside the pump P and the head T is of the order of 5 to 6 bars, and preferably 5.5 to 6 bars. Peaks at 7 to 8 bars are however possible, but we are then in abnormal conditions of use. Conversely, as we approach 2.5 bars, the spray deteriorates, between 2.5 and 2.2 bars, the spray is significantly altered, and below 2 bars, there is no more spray.

[0028] In the case of an aerosol equipped with a valve, the initial pressure generated by the propellant gas is around 12 to 13 bars and then drops, as the aerosol empties, to around 6 bars. An initial pressure of 10 bars is common in the perfume and cosmetics industry.

[0029] In comparison, in the technical field of ultrasonic vibration sprayers (particularly piezoelectric), the pressure of the fluid product at the nozzle is of the order of 1 bar, i.e. atmospheric pressure, or even slightly less. Due to the pressure value implemented and the energy used, these ultrasonic vibration sprayers are outside the scope of the invention.

[0030] We will refer to the figures 1 to 3 to describe in detail the constituent parts, as well as their mutual arrangement, of a distribution head T produced according to the invention.

[0031] The dispensing head T comprises two essential constituent elements, namely a head body T1 and a nozzle G. The head body T1 is preferably made in a single piece: it can however be made from several parts assembled together. The nozzle G can be made in a single piece from a single material, but preferably, it is made by overmolding, as will be seen below.

[0032] The head body T1 comprises a connecting sleeve which is mounted on the free end of an actuating rod of the dispensing member D. The head body T1 also comprises a lateral mounting housing T2 in which the nozzle G is engaged. The head body T1 also defines an upper bearing surface T3 on which a user can press using a finger.

[0033] The T dispensing head is presented here in the form of a classic pusher in the fields of perfumery, cosmetics or pharmacy.

[0034] The nozzle G has a substantially cylindrical overall configuration in the form of a small sleeve 2 which is closed by a spray wall 1 at the level of which several spray holes or orifices O1, O2 are formed. More precisely, the sleeve 2 has a substantially cylindrical overall shape, preferably with axial symmetry of revolution around an axis X, as shown in the Figures 2 and 3 . The sleeve 2 is preferably overmolded onto the spray wall 1. The nozzle G does not normally need to be angularly oriented before its presentation in front of the inlet of the axial mounting housing T2. The sleeve 2 forms an external mounting wall 21 which is advantageously provided with hooking reliefs capable of cooperating with the mounting housing T2.

[0035] The spray wall 1 may be a single-material single-piece part, an assembly of several parts or a multi-layer product, for example rolled. It may be made of metal, for example stainless steel. More generally, any material capable of being pierced with small holes or orifices can be used. The thickness of the spray wall 1, at the level where the holes O1, O2 are formed, is of the order of 10 to 100 µm and preferably of the order of 50 µm. The number of holes O1, O2 may vary from 10 to 500. The diameter of the spray wall 1, at the level where the holes are formed, is of the order of 0.5 to 5 mm. In principle, the spray wall 1 has a constant thickness, but it is not entirely flat. The holes O1, O2 have a diameter of the order of 1 to 100 µm, advantageously of the order of 5 to 30 µm, and preferably of the order of 5 to 20 µm.

[0036] On the figure 2, it can be seen that the spray wall 1 comprises an outer annular peripheral area 11, the outer part of which is embedded in the sleeve 2. This peripheral area 11 is also pierced with a first series of holes O2 which are arranged in a circle C2 around the X axis. These holes O2 have an orientation which extends along axes Y2 which are perpendicular to the peripheral area 11. It can also be said that the peripheral area 11 defines at each hole O2 a normal N which is perpendicular to the plane of the peripheral area 11. The axes Y2 of the holes O2 are coincident with their respective normals. The axes Y2 are therefore all parallel to each other, and in addition parallel to the X axis. The distance between the axes Y2 and the X axis is identical, given that the axes Y2 extend in a circle around the X axis.

[0037] The spray wall 1 also comprises a curved area 13 which is centered on the X axis. The curved area is convex from the outside. This curved area 13 can define a curvature corresponding to that of a circle, the center of which is positioned on the X axis. This curved area 13 is pierced with a second series of holes O1, which are also arranged in a circle C1 around the X axis. Consequently, the holes O1 are arranged concentrically inside the holes O2. The holes O1 extend along axes Y1, which are also coincident with their respective normals N. It can thus be said that the holes O1 are also made perpendicular to the spray wall 1. It can be seen on the figure 2that the Y1 axis extends divergently from the X axis, so that the Y1 and Y2 axes intersect at a collision point P. In order to ensure that the fluid product jet from a hole O1 meets the fluid product jet from a hole O2, the holes O1 and O2 are arranged aligned in pairs along a ray starting from the central X axis. This ensures that the Y1 and Y2 axes are inscribed in an orthogonal plane passing through the X axis and the two normals N of the pair of aligned holes O1 and O2. This orthogonal plane is that of the sheet for the figure 2. Thus, with a spray wall 1 pierced with two concentric circles C1 and C2 of 24 holes each, we obtain 24 collision points P, which together form a ring R whose diameter is identical to that of the circle C2 of the holes O2. The distance between the ring R and the peripheral area 11 depends on the more or less pronounced orientation of the axes Y1 and the spacing between the holes O1 and O2.

[0038] In this embodiment, which is not covered by the claims, the holes O1 and O2 may have an identical diameter. Alternatively, the diameter of the holes O1 of the small circle C1 is smaller than that of the holes O2 of the large circle C2.

[0039] Referring to the Figures 4 and 5, we see a second embodiment for a spray wall 1' pierced with concentric holes O1' and O2' centered on the central axis X. Just as in the first embodiment, the holes O1' and O2' extend along axes Y1, respectively Y2, which are coincident with their respective normals N. As can be seen on the figure 4 , the spray wall 1' also comprises a peripheral area 11 which is embedded in the sleeve 2. The wall 1' comprises an annular depression 12' which extends towards the inside of the sleeve 2. In the center, the wall 1' forms a central boss 13' centered on the axis X. The holes O1' and O2' are arranged in the two opposite flanks of the annular depression 12', such that the axes Y1 and Y2 are convergent, so as to intersect at collision points P. Here again, the holes O1' and O2' are aligned radially in pairs. The holes O1' may have a larger diameter than the holes O2'.

[0040] On the figures 6 and 7 , we see a third embodiment for a 1" spray wall comprising a peripheral area 11 and a concave curved zone 13" centered on the X axis. If the curved zone 13 of the figure 2can be described as convex, the 13" zone can be described as concave. This concave 13" zone is pierced with two series of holes O1" and O2", always arranged in concentric circles C1 and C2. Due to the concavity of the 13" area, the Y1 and Y2 axes of the holes O1' and O2' converge towards the X axis and all meet at a focal collision point Pf, itself located on the X axis. The O1" holes have a smaller diameter than the O2" holes. Although the O1" and O2" holes can be aligned radially in pairs, as is already the case in the two previous embodiments, this alignment is not mandatory here, since all the Y1 and Y2 axes converge towards a single collision focal point Pf. The advantage of this embodiment lies in the fact that a jet from any hole has a very high probability of meeting another jet from another hole, since there are 48 jets which are all oriented on the same point Pf.This embodiment can therefore be considered as a preferred embodiment.

[0041] The spray walls of the three embodiments just described can be produced using a manufacturing method in which parallel perpendicular holes are first drilled into a flat strip. Only the diameter of the holes can vary. This drilled flat strip is then stamped to profile it so as to cause the axes Y1, Y2 of the holes O1, O2 to intersect, in pairs as in the first two embodiments to form a ring R, or at a single focal point Pf, as in the third embodiment.

[0042] Alternatively, it is also possible to drill holes with an initial inclination in a flat strip, or conversely parallel holes in a bent or curved strip.

[0043] Whatever the manufacturing process used, the invention produces a spray wall with multiple micro-holes, the dispersion of whose droplets comes on the one hand from the fineness of the micro-holes and on the other hand from the collision between the jets coming from these converging holes.

[0044] The total number of holes, the arrangement of the holes on the spray wall, the number of holes per circle, the orientation of the holes and the diameter of the holes are all parameters that influence the characteristics of the spray. These parameters must be set according to the fluid product to be sprayed and the desired functions.

Claims

1. A fluid dispenser head (T) including a spray wall (1; 1', 1") that defines a central axis (X) and that is perforated with holes (01, 02; 01', O2'; O1", O2")of various diameters through which the fluid under pressure passes so as to form jets of fluid, the holes (01, 02; 01', 02'; 01", 02") extend along axes (Y1, Y2) that correspond to the path of the jets of fluid, at least some of the axes (Y1, Y2) intersecting, such that the jets of fluid that extend along the intersecting axes (Y1, Y2) meet at at least one collision point (P; Pf), the dispenser head being characterized in that the spray wall (1; 1'; 1") defines a normal (N) at each hole (01, 02; 01', O2'; 01", 02"), the axes (Y1, Y2) of the holes (01, 02; 01', O2'; 01", 02") coinciding with their respective normals (N).

2. A dispenser head according to claims 1, wherein the spray wall (1; 1'; 1") is shaped, so that it is not completely plane.

3. A dispenser head according to claim 1 or 2, wherein the holes (01, 02; O1', O2'; O1", O2") are arranged in concentric circles (C1, C2) that are situated respectively in zones that are concave and convex, in zones that are convex and plane, or in a single concave zone.

4. A dispenser head according to any preceding claim, wherein the holes (01, 02; 01', 02'; 01", O2") are aligned radially, at least in pairs of holes, so that the jets coming from the radially-aligned holes meet at a collision point P.

5. A dispenser head according to any preceding claim, wherein the holes (01") that are situated closest to the central axis (X) present a diameter that is smaller than the diameter of the holes (O2") that are situated furthest from the central axis (X).

6. A dispenser head according to any preceding claim, wherein the holes (O1, O2; O1', O2'; O1", O2") are arranged in concentric circles (C1, C2), namely a small inner circle C1 and a large outer circle (C2), all of the holes (O1; O1'; 01") of the small inner circle (C1) having the same diameter, and all of the holes (O2; O2'; O2") of the large outer circle (C2) having the same diameter, the holes (O1; O1'; 01") of the small inner circle (C1) presenting a diameter that is smaller than the diameter of the holes (02; O2'; O2") of the large outer circle (C2).

7. A dispenser head according to any preceding claim, wherein the number of holes (01, 02; 01', 02'; 01", O2") lies in the range 10 to 500, and the holes present a diameter lying in the range about 1 µm to about 100 µm, advantageously in the range about 5 µm to about 30 µm, and preferably in the range about 5 µm to about 20 µm.

8. A dispenser head according to any preceding claim, wherein the collision points (P) co-operate with one another to form a ring (R) or a focal point (Pf).

9. A dispenser head according to any preceding claim, comprising: - an assembly housing (T2), - a nozzle (G; G'; G") including a sleeve (2) that is engaged in the assembly housing (T2), the spray wall (1; 1'; 1") being secured to the sleeve (2).

10. A fluid dispenser comprising a fluid dispenser head (T) according to any one of claims 1 to 9 that is mounted on a pump (D) or a valve, which is itself mounted on a fluid reservoir.

11. A method of manufacturing a dispenser head according to any one of claims 1 to 9, the method comprising: - perforating a plane strip with parallel holes (O) that are perpendicular to the plane strip; and - stamping the perforated plane strip so as to shape it in such a manner as to cause the axes (Y1, Y2) of the holes (01, 02; 01', 02'; O1", 02") to cross.