Dispensing head

Abstract

The invention relates to a dispensing head comprising a nozzle (N) forming a spray orifice (O), the nozzle (N) forming, with the core (B2), a swirl chamber (C1) centred on the spray orifice (O) and several swirl channels (1) which open tangentially into the swirl chamber (C1), each swirl channel (1) of the nozzle (N) defining a bottom wall (10) and two side walls (11, 12), namely a long side wall (11) and a short side wall (12), characterized in that the long side wall (11) of a swirl channel (1) is connected to the short side wall (12) of an adjacent swirl channel (1) by a profile (13) which projects radially into the swirl chamber (C1).

Description

[0001] DISTRIBUTION HEAD

[0002] The present invention relates to a dispensing head comprising a body forming an insertion housing in which a core is arranged, and a nozzle inserted into the housing around the core. The nozzle is often in the form of a small cup defining a front wall which bears against the core and a cylindrical wall which engages around the core. The nozzle forms a spray orifice. It also forms, with the core, a swirl chamber centered on the spray orifice and several swirl channels which open tangentially into the swirl chamber. Each swirl channel of the nozzle defines a bottom wall and two side walls, namely a long side wall and a short side wall. This is a conventional configuration for a dispensing head to be mounted on a pump or valve in the fields of perfumery, cosmetics, pharmacy, etc.

[0003] Document FR2952360A1 describes a distribution head, the nozzle of which forms two swirl channels which open tangentially into a cylindrical swirl chamber, which then extends into a truncated cone-shaped compression chamber. The swirl channels, at the nozzle, each define a bottom wall and two side walls, namely a long side wall and a short side wall. The long side wall defines a downstream end which is tangent to the cylindrical internal wall of the swirl chamber. It can also be said that the cylindrical internal wall defines a circle and the long wall is tangent to this circle. It can be noted that the cylindrical internal wall of the swirl chamber is perfectly circular: it is interrupted only at the level where the swirl channels open into the swirl chamber.Therefore, the fluid flow from the swirl channels enters the swirl chamber following the cylindrical inner wall without any disturbance. In the prior art, document US2006249598A1 is also known, which describes a nozzle having a cylindrical swirl chamber defining a diameter of about 1 mm. The long side wall of a swirl channel is connected to the short side wall of an adjacent swirl channel by a rounded profile, which follows the diameter or circularity of the swirl chamber and which therefore does not protrude radially into the swirl chamber. It can even be noted in Figure 1 of this document that the distribution orifice is not even centered with respect to the swirl chamber, so that the teaching provided by Figure 1 is not certain.

[0004] It has long been known that the configuration of the swirl chamber, swirl channels, spray orifice and other elements of the nozzle and body affect the spray shape (length, aperture), spray duration (longer or shorter), spray cone sharpness, droplet size, etc. In short, the spray quality. It is also known that turbulence inside the dispensing head also affects spray quality. And this turbulence is generated by the configuration of the aforementioned elements.

[0005] On the other hand, most nozzles are normally made of polyoxymethylene, often referred to as POM, which is a thermoplastic material with a high degree of crystallinity, characterized by high strength and rigidity. However, it is difficult to recycle. The present invention set itself the objective of replacing POM with a more easily recyclable plastic material, such as polyolefins, such as polypropylene, often referred to as PP. However, the change in plastic material led to a deterioration in the spray quality. It was therefore necessary to review the design of the nozzle to regain the spray quality of the POM nozzle.

[0006] The goals to be achieved are diverse, including an explosive spray lasting approximately 0.1 sec, an angle of 30° (+ / - 10°), a circular or annular trace on a target and / or a very clean cone.To this end, the present invention provides a dispensing head comprising a body forming an insertion housing, in which a core is arranged, and a nozzle, advantageously made of polypropylene, inserted into the insertion housing around the core, the nozzle forming a spray orifice, the nozzle forming, with the core, a swirl chamber centered on the spray orifice and several swirl channels which open tangentially into the swirl chamber, each swirl channel of the nozzle defining a bottom wall and two side walls, namely a long side wall and a short side wall, in which the long side wall of a swirl channel is connected to the short side wall of an adjacent swirl channel by a profile which projects radially into the swirl chamber.This profile, which breaks the circularity of the swirl chamber, has the effect of further deflecting the flow of liquid coming from the swirl channel. The flow is thus more strongly disturbed than the circular cylindrical wall of document FR2952360A1. The profile acts as a deflector just before the exit of the next swirl channel.

[0007] Advantageously, the profile is rounded without edges. We can also say that it is continuous and smooth, without any breaks, discontinuities or sudden changes.

[0008] According to another feature, the profile may have a concave section and a convex section. The concave section connects to the long side wall and the convex section connects to the short side wall. The two sections connect to each other.

[0009] According to another aspect of the invention, the profile may have a maximum projection (or apex) into the swirl chamber which is closer to the short side wall than to the long side wall. This projection (or apex) is advantageously formed by the convex section.

[0010] Preferably, the profile connects seamlessly to the long side wall. According to another characteristic of the invention, the long side walls define inner ends which are tangent to an outer circle delimiting an outer periphery of the swirl chamber, the profiles projecting radially inside this outer circle. Advantageously, the profiles, at their maximum projections (or apexes), define an inner circle, concentric with the outer circle, the inner circle having a small diameter and the outer circle having a large diameter, the small diameter being of the order of 60 to 90%, advantageously of the order of 70 to 80% of the large diameter.

[0011] According to another aspect, the convex and concave sectors form segments of circular cylinders of different radii, which connect seamlessly to each other and to the long and short side walls. According to a practical embodiment, the concave sector which connects to the long side wall has a large radius, advantageously of the order of 0.2 mm, and the convex sector which connects to the short side wall has a small radius, advantageously of the order of 0.05 mm.

[0012] Advantageously, the side walls are flat. And even if they are not flat, their inner ends are still tangent to the outer circle.

[0013] Furthermore, the side walls of a swirl channel can make an angle of the order of 20° as they approach the swirl chamber.

[0014] According to another aspect of the invention, a compression chamber may be disposed between the swirl chamber and the spray orifice. The diameter of this compression chamber is smaller than that of the swirl chamber and larger than that of the spray orifice.

[0015] The spirit of the invention lies in the fact that the inner wall of the swirl chamber, between two swirl channels, does not coincide with a circle, but forms an inwardly projecting profile that breaks the circular cylindricity of the swirl chamber. By defining a circle that passes through the inner ends of the long side walls, the profiles can be said to penetrate this circle.

[0016] It should be noted that the profile characteristics mentioned above can be combined in different ways, such as:

[0017] - concave sector, circular cylindrical or not, connected with or without edge to the convex sector, circular cylindrical or not,

[0018] - concave sector, circular or non-circular cylindrical, connected with or without an edge to the long side wall,

[0019] - convex sector, circular or non-circular cylindrical, connected with or without an edge to the short side wall,

[0020] - long and / or short side walls, flat or curved.

[0021] However, according to a preferred embodiment, the long and short side walls are planar, the profiles connect seamlessly to the long and short side walls and are each made up of two segments of circular cylinders of different radii which connect seamlessly. The inner ends of the long side walls are tangent to an outer circle and the maximum projections of the profiles are tangent to an inner circle, the diameter of which is smaller than that of the outer circle.

[0022] The invention could also be defined as follows: the inner ends of the long side walls, which open into the swirl chamber, are further radially from the spray orifice than the tops of the profiles. Or: the profiles deflect the liquid flows from the swirl channels with a radial component towards the center of the swirl chamber.

[0023] Without departing from the scope of the invention, it is possible to envisage a nozzle with a single swirl channel and a single profile, which could then extend over almost all or only part of the periphery of the swirl chamber.

[0024] The nozzle is preferably made of polyolefin, advantageously polypropylene (PP), but it can more generally be made of any easily recyclable plastic material. The profile of the invention can even be implemented on conventional nozzles made of POM. The invention will now be described in more detail, with reference to the attached drawings, giving, by way of non-limiting example, an embodiment of the invention.

[0025] In the figures:

[0026] Figure 1 is a vertical cross-sectional view through a dispensing head according to one embodiment of the invention,

[0027] Figure 2 is a greatly enlarged perspective view of the nozzle of the dispensing head of Figure 1,

[0028] Figure 3 is a schematic view illustrating the interior of the nozzle of Figure 2, and

[0029] Figure 4 is a greatly enlarged view of the central part of Figure 3.

[0030] The dispensing head of the invention is intended to be mounted on the free end of a valve stem of a pump or a manual valve. By axially pressing on the head, the user actuates the pump or the valve, so as to dispense fluid product in metered or non-metered form. The dispensing head comprises two essential parts, namely a body B and a nozzle N. Both can be produced by injection / molding of suitable plastic material, such as a polyolefin, and in particular polypropylene.

[0031] The body B defines an insertion housing B1, in which extends a cylindrical core B2 with a flat front wall B21. Upstream, the receiving housing B1 is connected to a conduit B4, which itself is connected to a mounting sleeve B3. Thus, the fluid product from the valve stem of the pump or the valve flows through the body B of the dispensing head through the sleeve B3, the conduit B4 and into the receiving housing B1. This is a completely conventional feature for the body of a dispensing head in the fields of cosmetics, perfumery or even pharmacy.

[0032] The nozzle N is generally in the form of a small cup, which is engaged in the receiving housing B1 around the core B2. The nozzle N has the function of conditioning the fluid product coming from the body B, so as to generate a swirl or vortex which emerges from the nozzle in the form of a spray or cloud of fine sprayed droplets. The nozzle N thus forms an outlet channel whose end defines a spray orifice O. By abuse of language, the expression "spray orifice O" also covers the outlet channel. The nozzle N also defines, together with the core B2, connecting passages N21, swirl channels 1, and a swirl chamber C1. Optionally, the nozzle N can also form a compression chamber C2.

[0033] The nozzle N will now be described in more detail with reference to Figure 2. The nozzle N comprises a bottom wall N1 and a peripheral wall N2, which connect in such a way as to form a small cup. The bottom wall N1 is intended to come into contact with the front wall B21 of the core B2. As for the peripheral wall N2, it is intended to engage around the core B2 inside the housing B1. This peripheral wall N2 internally defines several connecting passages N21 in the form of small axial grooves. These axial grooves are completed by the peripheral wall of the core B2 to form the connecting passages N21. The bottom wall N1 defines in hollow the swirl channels 1, which extend substantially radially. Again, these swirl channels 1 are in the form of grooves, which will be completed by the front wall B21 of the core B2.The swirl channels 1 are respectively connected to the connecting passages N21. At the nozzle N, each swirl channel 1 comprises a bottom wall 10 and two side walls 11 and 12. The side wall 11 is longer than the side wall 12. The side walls 11 and 12 are not parallel, but extend relative to each other with an angle of the order of 20°, oriented in such a way that each swirl channel 1 narrows towards the swirl chamber C1. The swirl channels 1 open substantially tangentially into the swirl chamber C1, the bottom wall of which advantageously merges with the bottom wall 10 of the swirl channels 1. Alternatively, it is also conceivable that the bottom wall 10 of the swirl channels 1 forms an angle relative to the bottom wall of the swirl chamber C1.Of course, the swirl chamber C1 visible in Figure 2 is completed by the front wall B21 of the core B2 of the body B. The nozzle N also forms a small compression chamber C2, which extends downstream of the swirl chamber C1. The compression chamber C2 defines a cylindrical wall which is extended by a truncated conical shoulder, which connects to the spray orifice O, which is cylindrical here. The presence of this compression chamber C2 is optional.

[0034] According to the invention, the bottom wall N1 forms profiles 13, which project towards the inside of the swirl chamber C1. Each profile 13 connects a long side wall 11 to a short side wall 12. The function of these profiles 13 is to deflect the flow of fluid product from the swirl channels 1 towards the center of the swirl chamber C1. It can also be said that the profiles 13 form a sort of springboard towards the inside of the swirl chamber C1.

[0035] The side walls 11 and 12 are preferably straight and / or flat, so that the profile 13 can be defined as the curved portion connecting two adjacent flat walls 11 and 12 belonging to two adjacent swirl channels.

[0036] Figure 3 shows more clearly the arrangement of the swirl channels 1, which extend from the connecting passages N21 towards the swirl chamber C1, which is centered on the spray orifice O. It can be seen that the profiles 13 project inside the swirl chamber C1 and approach radially the spray orifice O.

[0037] Figure 4, which is an enlargement of the center of Figure 3, makes it possible to describe a preferred embodiment of the invention, with regard to the profiles 13, which form a connection between the long side walls 11 and the short side walls 12, respectively. In this respect, it can be said that the long side walls 11 define internal ends 112 which are tangent to an external circle Ce, which defines the external periphery of the swirl chamber C1. It can be clearly seen in Figure 4 that this circle Ce intersects the profiles 13, which therefore extend inside this external circle Ce. In the absence of the profiles 13, the peripheral wall of the swirl chamber C1 would be formed by the arc of a circle connecting the internal ends 112 of the long side walls 11 to the short side walls 12. The profiles 13 interrupt the circularity of the swirl chamber C1 by projecting radially inwards.The profiles 13 each define a vertex 130, which is located closest to the spray orifice O. It is thus possible to define an internal circle Ci which passes the vertices 130 of the profiles 13. This internal circle Ci of course has a diameter smaller than that of the external circle Ce, for example of the order of 10 to 40%, advantageously of the order of 20 to 30%.

[0038] As regards the shape of the profiles 13, it can be noted that each profile 13 comprises a concave section 131 and a convex section 132. These two sections 131 and 132 are connected to each other, preferably without any edge or discontinuity. The concave section 131 is connected to the inner end 112 of the long side wall 11 and the convex section 132 is connected to the short side wall 12. Preferably, the concave section 131 connects to the inner end 112 of the long wall 11 without any edge or discontinuity. Thus, it can be said that the connecting part of the concave section 131 is tangent to the outer circle Ce, as is the inner end 112. It can also be noted that the concave section 131 is longer than the convex section 132. Therefore, the vertex 130 is closer to the short side wall 12 than to the inner end 112 of the long side wall 11.

[0039] According to a preferred embodiment, the concave section 131 and the convex section 132 both form circular cylindrical segments of different radii. In the embodiment that has been used to illustrate the present invention, there are three swirl channels 1 and therefore three profiles 13. The radius of the circular cylindrical segment forming the concave sector 131 is much larger than that forming the convex sector 132. The radius ratio can be 4 to 1. As an indication, the radius of the circular cylinder segment forming the concave sector 131 can be of the order of 0.2 mm, while the circular cylinder segment forming the convex sector 132 can be of the order of 0.05 mm. The two concave 131 and convex 132 sectors connect substantially at the vertex 130 of the profile 13.In a preferred embodiment, the concave 131 and convex 132 sectors in the form of a circular cylinder segment connect to each other and to the long side wall 11 and the short side wall 12 without discontinuity or edge, so that the profile 13 can be described overall as round or rounded. However, it is not excluded that the connection of the convex sector 132 with the short side wall 12 forms an angle or an edge.

[0040] In the embodiment of Figures 2 to 4, the long 11 and short 12 side walls are flat or rectilinear. Without departing from the scope of the invention, it is very possible to imagine walls 11 and / or 12 which are curved or profiled. However, it would still be advantageous for the inner ends of the long side walls 11 to open tangentially into the swirl chamber C1, that is to say for them to be tangent to the outer circle Ce.

[0041] Although the description has been made with reference to a nozzle N comprising three swirl channels 1 , it is possible to easily imagine that a nozzle may have more or fewer swirl channels. It is even possible to envisage a nozzle with a single swirl channel 1 , so that the profile 13 connects the long side wall 11 to the short side wall 12 of the same swirl channel. In this case, the profile 13 may extend progressively over all or part of the peripheral wall of the swirl chamber C1 .

[0042] Thanks to the invention, it is possible to produce a nozzle made of polyolefin, for example polypropylene, instead of POM, without degrading the quality of the spray, as defined above. The profiles 13 break the cylindricity of the swirl chamber and induce additional turbulence which positively influences the quality of the spray.

Claims

Claims 1. Dispensing head comprising a body (B) forming an insertion housing (B1), in which a core (B2) is arranged, and a nozzle (N), advantageously made of polypropylene, inserted into the insertion housing (B1) around the core (B2), the nozzle (N) forming a spray orifice (O), the nozzle (N) forming, with the core (B2), a swirl chamber (C1) centered on the spray orifice (O) and several swirl channels (1) which open tangentially into the swirl chamber (C1), each swirl channel (1) of the nozzle (N) defining a bottom wall (10) and two side walls (11, 12), namely a long side wall (11) and a short side wall (12),characterized in that the long side wall (11) of a swirl channel (1) is connected to the short side wall (12) of an adjacent swirl channel (1) by a profile (13) which projects radially into the swirl chamber (C1)., 2. Dispensing head according to claim 1, in which the long side walls (11) define inner ends (112) which are tangent to an external circle (Ce) delimiting an external periphery of the swirl chamber (C1), the profiles (13) projecting radially inside this external circle (Ce).

3. Dispensing head according to claim 2, in which the profiles (13) have vertices (130) which define an internal circle (Ci), concentric with the external circle (Ce), the internal circle (Ci) having a small diameter and the external circle (Ce) having a large diameter, the small diameter being of the order of 60 to 90%, advantageously of the order of 70 to 80% of the large diameter.

4. Dispensing head according to any one of the preceding claims, in which the profile (13) is rounded without edges.

5. Dispensing head according to any one of the preceding claims, in which the profile (13) has a concave section (131) and a convex section (132).

6. Dispensing head according to any one of the preceding claims, wherein the profile (13) has a maximum projection (130) into the swirl chamber (C1) which is closer to the short side wall (12) than to the long side wall (11).

7. Dispensing head according to any one of the preceding claims, in which the profile (13) connects seamlessly to the long side wall (11).

8. Dispensing head according to claim 5, in which the concave (131) and convex (132) sectors form circular cylindrical segments of different radii, which connect seamlessly to each other and to the long (11) and short (12) side walls.

9. Dispensing head according to claim 8, wherein the circular cylinder segment (131) which connects to the long side wall (11) has a large radius, advantageously of the order of 0.2 mm, and the circular cylinder segment (132) which connects to the short side wall (12) has a small radius, advantageously of the order of 0.05 mm.

10. Dispensing head according to any one of the preceding claims, in which the side walls (11, 12) are flat.

11. Dispensing head according to any one of the preceding claims, in which the side walls (11, 12) of a swirl channel (1) make an angle of the order of 20° as they approach the swirl chamber (C1).

12. Dispensing head according to any one of the preceding claims, in which a compression chamber (C2) is arranged between the swirl chamber (C1) and the spray orifice (O).

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