DIFFUSER OUTLET DUCT

Abstract

A diffuser outlet duct for a pressurized container fitted with a valve, equipped with: a passage between a first end and a second end. The first end is configured to collaborate with the valve of the pressurized container. The second end is configured for expelling the product contained in the pressurized container. The passage is defined by a first section, a second section, and a junction connecting the first section and the second section. The first section begins at the first end and terminates at the junction. The second section at the junction and terminates at the second end. The first section extends over a first length l1, and the second section extends over a second length l2. The second length l2 is less than 10 mm, preferably less than 9 mm, more preferably less than 8 mm.

Claims

1. An outlet duct of a diffuser for a pressurized container fitted with a valve, said outlet duct being provided with: a passage between a first end and a second end, said first end being configured to cooperate with the valve of the pressurized container, said second end being configured for the release of the product contained in the pressurized container; wherein said passage is defined by a first section, a second section, and a junction connecting the first section and the second section, said first section starting at the first end and ending at the junction, said second section starting at the junction and ending at the second end; and wherein the first section extends over a first length l1 and the second section extends over a second length l2, said second length l2 being less than 10 mm.

2. The outlet duct according to claim 1, wherein the junction comprises a shoulder of the passage, said shoulder of the passage defining a reduction in the lateral dimension of the passage between the first section and the second section.

3. The outlet duct according to claim 1, wherein the second section is substantially straight over at least 80%.

4. The outlet duct according to claim 1, wherein the first end is substantially perpendicular to a first longitudinal axis A1; wherein the second end is substantially perpendicular to a second longitudinal axis A2; and wherein an angle α formed between the first longitudinal axis A1 and the second longitudinal axis A2 is between 94° and 105°.

5. The outlet duct according to claim 1, wherein the first section comprises a coupling section extending over a third length l3, said coupling section being defined by the part of the passage between the first end and a shoulder of the passage forming a stop for a flow restrictor of the valve of the pressurized container; and wherein the third length l3 is less than 6 mm.

6. The outlet duct according to claim 5, wherein the outlet duct is provided with a lug configured to be attached to a base body of the diffuser, said lug being provided at the junction and being substantially aligned with the first section.

7. The outlet duct according to claim 6, wherein the lug comprises a rod, a shoulder, and a cap connected to the outlet duct by the rod and the shoulder, said rod ending, opposite the cap, with the shoulder.

8. The outlet duct according to claim 7, wherein the rod of the lug extends over less than 0.95 mm.

9. The outlet duct according to claim 6, wherein the outlet duct is provided with a hollow compartment between the lug and the passage.

10. The outlet duct according to claim 1, wherein the second section is an inner duct, said inner duct being surrounded by an outer duct; and wherein the inner duct and the outer duct define a substantially annular housing, said housing being configured to cooperate with a nozzle.

11. The outlet duct according to claim 10, wherein the second end (22) is housed inside the outer duct (243), and wherein a fourth length l4 between the second end (22) and one end of the outer duct (243) is less than 2.5 mm.

12. A diffuser for a pressurized container fitted with a valve, especially for an aerosol generator, which diffuser is provided with: a base body having a finger tab to be depressed by the user to actuate the valve, and having an outlet opening for releasing the product contained in the container; an outlet duct according to claim 1, said outlet duct being attached to the base body such that the second end of the outlet duct is substantially facing the outlet opening of the base body.

13. The diffuser for a pressurized container according to claim 12, wherein the base body is provided with a connecting hole being a through-hole between an outer surface of the finger tab and an inner surface of the finger tab, wherein the outlet duct comprises: a passage between a first end and a second end, said first end being configured to cooperate with the valve of the pressurized container, said second end being configured for the release of the product contained in the pressurized container; wherein said passage is defined by a first section, a second section, and a junction connecting the first section and the second section, said first section starting at the first end and ending at the junction, said second section starting at the junction and ending at the second end; wherein the first section extends over a first length l1 and the second section extends over a second length l2, said second length l2 being less than 10 mm; wherein the first section comprises a coupling section extending over a third length l3, said coupling section being defined by the part of the passage between the first end and a shoulder of the passage forming a stop for a flow restrictor of the valve of the pressurized container; wherein the third length l3 is less than 6 mm; and wherein the outlet duct is provided with a lug configured to be attached to a base body of the diffuser, said lug being provided at the junction and being substantially aligned with the first section; and wherein the lug is attached via the connecting hole of the base body to fix the outlet duct to the base body.

14. The diffuser for a pressurized container according to claim 13, wherein the second end of the outlet duct is floating in relation to the base body; and wherein the minimum distance between a first point, said first point being a point of the connecting hole on the outer surface of the finger tab, and a second point, said second point being a point of the outlet opening on the outer surface of the base body, is less than 12 mm.

15. The diffuser for a pressurized container according to claim 1, wherein the base body has a minimum thickness of less than 0.8 mm.

16. The diffuser according to claim 12, wherein the base body is formed by an outer wall, and wherein a lower part of the outer wall is configured for cooperating with a cylindrical end of the container.

17. An outlet duct of a diffuser for a pressurized container fitted with a valve, said outlet duct being provided with: a passage between a first end and a second end, said first end being configured to cooperate with the valve of the pressurized container, said second end being configured for the release of the product contained in the pressurized container; wherein said passage is defined by a first section, a second section, and a junction connecting the first section and the second section, said first section starting at the first end and ending at the junction, said second section starting at the junction and ending at the second end; wherein the first section extends over a first length l1 and the second section extends over a second length l2, said second length l2 being less than 10 mm; wherein the first section comprises a coupling section extending over a third length l3, said coupling section being defined by the part of the passage between the first end and a shoulder of the passage forming a stop for a flow restrictor of the valve of the pressurized container; and wherein the third length l3 is less than 6 mm.

18. The outlet duct according to claim 17, wherein the outlet duct is provided with a lug configured to be attached to a base body of the diffuser, said lug being provided at the junction and being substantially aligned with the first section.

19. The outlet duct according to claim 18, wherein said lug is further configured to be attached through a through-hole of a finger tab of the base body between an outer surface of the finger tab and an inner surface of the finger tab to fix the outlet duct to the base body.

20. An outlet duct of a diffuser for a pressurized container fitted with a valve, said outlet duct being provided with: a passage between a first end and a second end, said first end being configured to cooperate with the valve of the pressurized container, said second end being configured for the release of the product contained in the pressurized container; wherein said passage is defined by a first section, a second section, and a junction connecting the first section and the second section, said first section starting at the first end and ending at the junction, said second section starting at the junction and ending at the second end;

Description

BRIEF DESCRIPTION OF THE FIGURES

[0049] These and other aspects of the present invention will now be described in more detail, with reference to the attached drawings which show examples of embodiments of the invention. Identical numbers refer to identical features in all the drawings.

[0050] FIGS. 1A-1B show an exploded perspective view and a longitudinal cross-sectional perspective view, respectively, of the diffuser, the pressurized container's valve, and the pressurized container according to an embodiment of the invention;

[0051] FIGS. 2A and 2B show a perspective view and a longitudinal cross-sectional view, respectively, of an outlet duct according to an exemplary embodiment of the invention;

[0052] FIG. 3 shows a longitudinal cross-sectional view of another embodiment of a diffuser and an outlet duct according to the invention.

DETAILED DESCRIPTION OF THE INVENTION

[0053] FIGS. 1A-1B show an exploded perspective view and a longitudinal cross-sectional perspective view, respectively, of the diffuser, the pressurized container's valve, and the pressurized container according to an exemplary embodiment of the invention. The invention relates to an outlet duct 1120 and a diffuser 1100 for a pressurized container 1020, especially for an aerosol generator, a foam generator, a dispenser system for gel, cream, or other paste or liquid products, etc. The diffuser 1100 is used to actuate the valve 1030 of the container in order to remove some of the contents from the pressurized container 1020 and to dispense it in the form of an aerosol or foam, for example. Pressurized containers 1020 are generally made of a casing 1021 fitted with a neck closed with a valve 1030 mounted on a valve cup 1035. Sometimes the valve cup 1035 is attached to the casing 1021 by way of a dome 1022. When the valve 1030 is male type, a flow restrictor 1031 or stem protrudes from the valve 1030.

[0054] The diffuser 1100 comprises a base body 1110 and an outlet duct 1120. The base body 1110 may have a cavity formed by an outer wall 1111 of the base body or provided in a substantially solid body. The outlet duct 1120 can be fully or partially housed within the cavity formed by the outer wall 1111. The outer wall 1111 may comprise concave and/or convex parts. The base body 1110 provided with a cavity formed by the outer wall 1111 of the base body may have a minimal thickness, optionally the main part of its thickness, of less than 0.8 mm, preferably less than 0.7 mm, more preferably less than 0.6 mm.

[0055] Pressurized containers 1020 generally have a cylindrical end on which the base body 1110 will be fixed. The flow restrictor 1031 or stem of a valve of male type protrudes from this end and is centred in relation to this end. The flow restrictor 1031, the main body of the valve 1030, and the cylindrical end of the pressurized container 1020 are aligned along an axis A. In order to cooperate with the container's cylindrical end, a lower part of the outer wall 1111 of the base body may exhibit rotational symmetry around axis A when attached to the container.

[0056] The base body 1110 may be provided with a fastening ring 1112 which allows it to be fastened either directly to the pressurized container, particularly on the casing or the valve, or by means of a collar. This fastening ring 1112 may be fitted with fastening means arranged continuously or at regular intervals along the periphery of the fastening ring. These fastening means may be intended to cooperate with complementary fastening means created on the pressurized container's casing 1020 or the valve 1030, or on the collar 1023. In particular, the series of gadroons 1112 regularly distributed as shown in FIG. 1B may snap behind a rolled edge 1024 at the interface between the casing 1021 and the valve cup 1035 or between the casing 1021 and the dome 1022 on which the valve cup 1035 is fastened. Other fastening means may be considered, such as a continuous rib, a thread for a screw connection, increased thickness or material for welding, glue for bonding, etc.

[0057] The base body wall 1111 may have a finger tab opening 1113 in which the finger tab 1130 sits. The finger tab 1130 may be attached to the rest of the base body 1110 by a tongue 1131 which serves as a hinge such that when pressure is exerted on the finger tab 1130 towards the inside of the base body 1110, thus towards the valve 1030 when the diffuser 1100 is fastened on the pressurized container 1020, the finger tab 1130 pivots around an axis which passes transversely through the tongue 1131. In the example of FIGS. 1A-1B, the finger tab 1130 and the corresponding finger tab opening 1113 are situated near the top of the base body 1110. In other embodiments, the finger tab 1130 may be separate from the base body 1110 and be depressed either in a vertical translational motion or in a rocking motion around a support.

[0058] An outlet opening 1114 may be created in the wall 1111 of the base body. The outlet opening 1114 may be configured so that the product withdrawn from the pressurized container passes through it when being released from the outlet duct 1120. The adjectives “front” and “rear” refer to this release of the product through the outlet opening 1114, the product being released through a front section of the diffuser 1100 with the rear section being opposite to it. In the example of FIGS. 1A-1B, the finger tab 1130 is fastened to the rest of the base body 1110 by the tongue 1131 situated to the rear of the finger tab 1130. In another exemplary embodiment, the finger tab may be fastened by the tongue situated to the front of the finger tab.

[0059] The base body 1110 may include a connecting portion, e.g. a connecting hole, configured to be connected to the outlet duct 1120 in such a way that the outlet duct 1120 and the base body 1110 are attached together. In the example of FIGS. 1A-1B, the connecting hole 1140 is a through-hole between an outer surface of the base body 1110 and an inner surface of the base body 1110, and is configured to facilitate the attachment of the outlet duct 1120 such that the outlet duct 1120 may be fastened to the base body 1110. The outlet duct 1120 may be fastened to the base body 1110 by joining them mechanically, by bonding, welding, and/or heat-bonding.

[0060] In the example of FIGS. 1A-1B, the connecting hole 1140 is located in the longitudinal cross-section plane of the base body 1110, on a front part of the finger tab 1130. The minimum distance between a first point, said first point being a point of the connecting hole 1140 on the outer surface of the finger tab 1130, and a second point, said second point being a point of the outlet opening 1114 on the outer surface of the base body 1110, may be less than 12 mm, preferably less than 10 mm, more preferably less than 8 mm, and is less than 8 mm in this example.

[0061] Due to the presence of a connecting portion used for attaching the outlet duct 1120 to the base body 1110, these two elements of the diffuser 1100 can be made from different materials. The material for the outlet duct 1120 can be selected to be compatible with the product contained in the pressurized container, whilst the material for the base body 1110 does not need to satisfy this condition, but can be selected for its mechanical properties or its environmental and/or economic value, e.g. a recycled material. For example, if the diffuser 1100 is to be used for a food product, the material for the outlet duct 1120 may be of food grade quality, whilst this would not be required of the material for the base body 1110 as it does not come into contact with the product.

[0062] Depending on what fastening is used to attach the outlet duct 1120 to the base body 1110, materials can be selected either to be compatible or not. Possible materials for the base body 1110 could include polymer materials (PE, PP, PLA, PHA, PBS), which could be new or recycled, petroleum-based or from natural resources, biodegradable or not, including compostable or not. They could contain mineral fillers, e.g. basalt glass, and could be reinforced with mineral or vegetable fibres. Non-polymer materials, such as lignin-based materials, could also be considered, e.g. cardboard, wood, materials containing textiles, or metals, etc. As a non-limiting example, polymers (PE, PP, POM, PBT, PA, etc.), which are injectable materials, or machinable materials such as metals, e.g., aluminium, steel, and especially stainless steel, could be used for the outlet duct 1120.

[0063] A more detailed description of the outlet duct 1120 can be read below with reference to FIGS. 2A-2B.

[0064] FIGS. 2A-2B respectively show a perspective view and a longitudinal cross-sectional view of an outlet duct according to an exemplary embodiment of the invention. The outlet duct 20 to be placed into a base body of the diffuser has a passage 10 between a first end 21 and a second end 22.

[0065] The first end 21 of the outlet duct is configured to cooperate with the valve of the pressurized container. The second end 22 of the outlet duct is configured for the release of the product contained in the pressurized container. In a fastened state of the outlet duct 20 to the base body, the second end 22 may be oriented so as to correspond with an outlet opening of the base body. The second end 22 may be configured to be fixed or floating in relation to the outlet opening of the base body, and is shown floating in this example.

[0066] The outlet duct 20 has, at the first end 21, means to actuate the valve. If the valve is of female type, the first end 21 may comprise a rod intended to penetrate the valve to actuate it. If the valve of male type, the first end 21 may be splayed to facilitate the introduction of the flow restrictor when mounting the outlet duct 20 on the pressurized container.

[0067] Depending on the functions of the passage 10, the outlet duct 20 may be divided between at least a first section 21, a second section 23, and a junction connecting the first section 23 to the second section 24. The first section 23 is configured to cooperate, by way of the first end 21, with the valve of the pressurized container. The valve itself may be of the male or female type. The first section 23 may also be provided with an extraction chamber configured to extract the product from the pressurized container on actuation of the valve of the pressurized container.

[0068] The second section 24, ending with the second end 22, is configured for the release of the product. The second end 22 of the outlet duct may be provided with a nozzle to modify the properties of the product projection. Depending on the product contained, the internal lateral dimensions of the passage 10 in this second section 24 may be adapted depending on the nature of the product, material of the outlet duct, and rheological properties of the product, so as to obtain a predetermined extraction quality, e.g. an aerosol.

[0069] The first section 23 may comprise a coupling section 231 extending over a third length l3. The coupling section 231 may be defined by the part of the passage 10 between the first end 21 and a shoulder of the passage forming a stop for a flow restrictor of the valve of the pressurized container. The third length l3 may be less than 6 mm, preferably less than 5.5 mm, more preferably less than 5 mm, and is less than 5 mm in this example.

[0070] The first section 23 and the second section 24 may be aligned or at an angle to each other, they are shown at an angle in FIGS. 2A-2B. The first end 21 may be substantially perpendicular to a first longitudinal axis A1. The second end 22 may be substantially perpendicular to a second longitudinal axis A2. The first longitudinal axis A1 and the second longitudinal axis A2 form a tilt angle α between the first section 23 and the second section 24.

[0071] The tilt angle α between the first longitudinal axis A1 and the second longitudinal axis A2 may be in a range from 94° and 105°, preferably between 96° and 103°, more preferably between 98° and 100°. In this example, the tilt angle α is substantially equal to 99° to compensate for a rotation of the outlet duct 20 around an axis which is perpendicular to the pressurized container on actuation of the valve. The path of the projected product can thus be substantially perpendicular to the pressurized container.

[0072] The first section 23 extends over a first length l1 and the second section 24 extends over a second length l2. The second length l2 may be less than 10 mm, preferably less than 9 mm, more preferably less than 8 mm, and is less than 8 mm in FIGS. 2A-2B. The second section 24 may be substantially straight over at least 80%, preferably over at least 90%, more preferably over at least 95%, most preferably over 100%, of the second length l2 so as to define the path of the product projected by the outlet duct 20 in the desired manner, and it is straight over 100% of l2 in this example.

[0073] The junction connecting the first section 23 and the second section 24 may be defined by a change in the general direction of the second section 24 in relation to the first section 23. Additionally or alternatively, the junction may be defined by a section where the diameter of the passage 10 reduces from a maximal diameter at the first section 23 to a minimum diameter at the second section 24.

[0074] In the example of FIGS. 2A-2B, the junction comprises a shoulder of the passage. The shoulder of the passage 10 defines an immediate reduction in the lateral dimension of the passage 10 between the first section 23 and the second section 24. The length of the junction may thus advantageously be zero. In another embodiment, see FIG. 3, the junction may comprise a gradual reduction in the lateral dimension of the passage 10 between the first section 23 and the second section 24.

[0075] In order for the nozzle to be fitted, the second section 24 may be provided—towards the second end 22—with a nozzle housing 241. In the example of FIGS. 2A-2B, the second section 24 is an inner duct surrounded by an outer duct 243. The annular housing 241 between the inner duct 24 and the outer duct 243 constitutes the nozzle housing 241. A fourth length l4 between the second end 22 and one end of the outer duct 243 may be less than 2.5 mm, preferably less than 2.4 mm, more preferably less than 2.3 mm, most preferably less than 2.2 mm.

[0076] In this example, length l4 is less than 2.2 mm and is suitable for inserting and retaining the nozzle in the housing 241 defined with the inner duct 24. The nozzle may be mechanically attached, welded, chemically bonded and/or heat-bonded in the housing 241 at the end of the second end 22. The nozzle may be manufactured from a material that is similar or different from the material of the outlet duct 20, whilst being compatible with the product contained in the pressurized container. If the diffuser does not have a nozzle, an outer duct 243 may not be needed.

[0077] To fasten the outlet duct 20 to the base body, the outlet duct 20 may comprise a lug 25. In the example of FIGS. 2A-2B, the lug 25 is joined to the top of the first section 23 of the outlet duct and, when the outlet duct 20 is fastened to the base body, extends coaxially to the first longitudinal axis A1. According to another embodiment, the lug 25 may be provided at the junction and extend in a substantially aligned manner with the first section 23. According to yet another embodiment, the lug 25 may extend obliquely in relation to the first longitudinal axis A1.

[0078] The lug 25 of the outlet duct can be inserted into a connecting portion of the base body, or joined thereto, in such a way that it cannot come loose on its own. The inserted lug 25 can join the outlet duct 20 and the base body in a mechanical way, through welding, chemical bonding and/or heat-sealing. The lug 25 of the outlet duct thus facilitates the attachment of the outlet duct 20 to the base body and, through its connection to a dedicated connecting portion, facilitates the positioning of the outlet duct 20 in relation to the base body.

[0079] To fasten the outlet duct 20 to the base body in the embodiment of FIGS. 2A-2B, the lug 25 is provided with a part configured to cooperate with a complementary connecting portion, a connecting hole, created in a finger tab of the base body. The lug 25 is intended to be snapped into a connecting hole of the finger tab to mechanically join the outlet duct 20 to the base body.

[0080] The lug 25 may include a substantially cylindrical rod 251 which may be attached by its first end to the outlet duct 20, said rod 251 having, at its second end, a cap 252 which has a larger cross-section than the rod 251.

[0081] The junction between the rod 251 and the rest of the outlet duct 20 may constitute a shoulder 253 at a distance from the cap 252. In this case, the lug 251, 252, 253 comprises a cylinder in which an annular groove is made. The top of the cylinder corresponds to the cap 252.

[0082] The annular groove forms the rod 251. The rod 251 of the lug may extend over a length l.sub.T of less than 0.95 mm, preferably of less than 0.85 mm, more preferably of less than 0.75 mm. In this example, the rod 251 of the lug extends over 0.75 mm to correspond to the thickness of the wall forming the finger tab of the base body.

[0083] The part of the cylinder opposite the cap 252 corresponds to the shoulder 253. The lug 25 may be joined to the outlet duct 20 by a hollow compartment 26. In this example, the hollow compartment 26 has a parallelepiped shape so as to be simple and structurally rigid. The hollow compartment 26 can act as the shoulder 253.

[0084] FIG. 3 shows a longitudinal cross-sectional view of another embodiment of a diffuser and an outlet duct according to the invention. The diffuser 3000 comprises a base body 1110 and an outlet duct 300.

[0085] The base body 1110 may include an outer wall 1110. The outer wall may form a cavity, and the outlet duct 300 may be fully or partially housed in the cavity formed by the outer wall 1111, and is shown as fully housed in this example. The outer wall 1111 may comprise concave and/or convex parts.

[0086] The diffuser 3000 is a diffuser for a pressurized container. The pressurized container may include a cylindrical end. In order to cooperate with the cylindrical end of the container, a lower part of the outer wall 1111 of the base body may exhibit rotational symmetry around axis A when attached to the container. The base body 1110 may be configured to be attached to the pressurized container by means of a fastening ring 1112. In this example, the fastening ring 1112 has a series of gadroons regularly distributed along the periphery of an inner surface of the outer wall 1111 of the base body. The fastening ring 1112 may be adapted to snap behind a rolled edge of the upper end of the pressurized container.

[0087] The base body 1110 may include a finger tab 1130 to be depressed by the user in order to actuate the pressurized container's valve. The outer wall 1111 of the base body may be pierced with a finger tab opening in which the finger tab 1130 sits. The finger tab 1130 may be attached to the rest of the base body 1110 by a tongue 1131 behind the finger tab 1130 which serves as a hinge such that the finger tab 1130 pivots around an axis which passes transversally through the tongue 1131.

[0088] An outlet opening 1114 may be created in the outer wall 1111 of the base body. The outlet opening 1114 may be configured so that the product withdrawn from the pressurized container passes through it when being released from the outlet duct 300. In the embodiment of FIG. 3, the finger tab opening is on a lateral part of the outer wall 1111 and the outlet opening 1114 is on a top surface of the outer wall 1111 of the base body, substantially aligned with axis A.

[0089] The base body 1110 includes a connecting hole 1140. In this example, the finger tab 1130 is provided with one connecting hole 1140. The connecting hole 1140 may be a through-hole between an outer surface of the finger tab 1130 and an inner surface of the finger tab 1130 and may extend substantially perpendicular to axis A. A person skilled in the art will understand that multiple variations of connecting holes 1140 may be achieved by varying, for example, the number, dimensions, positioning or profile of the connecting holes.

[0090] The connecting hole 1140 may be configured to cooperate with a connecting means of the outlet duct 300 such as a lug 325, for example. In this example, the outlet duct 300 may comprise a lug which extends substantially perpendicular to axis A and is to be introduced into the corresponding connecting hole 1140 so that the outlet duct 300 is fastened to the base body 1110. The outlet duct 300 may be held by the lug 325, introduced in the corresponding connecting hole 1140 by interlocking, bonding, heat-bonding, welding, etc.

[0091] The outlet duct 300 placed in the base body 1110 has a passage 10 between a first end 321 and a second end 322. The first end 321 is configured to cooperate with the pressurized container's valve. The second end 322 is configured for the release of the product contained in the pressurized container. In a fastened state of the outlet duct 300 to the base body 1110, the second end 322 is oriented so as to correspond to the outlet opening 1114. The second end 322 may be floating in relation to the outlet opening 1114.

[0092] The outlet duct 300 may be divided up between a substantially straight first section 323 of length l1, a second section 324 of length l2 which is aligned in relation to the first section 323 and is substantially coaxial with axis A, and a junction of length l.sub.J which connects the first section 323 and the second section 324. The second section 324 comprises a single passage-forming duct 10 and the outlet duct 300 is not equipped to accommodate a nozzle in this example.

[0093] The first section 323 may start at the first end 321 and end at the junction. The first section 323, the second section 324, and the junction may form the passage 10 between the first end 321 and the second end 322. In this example, the second section 324 has a substantially constant diameter over its length l2, and the junction starts with a gradual increase in said diameter and ends with a shoulder. The first section 324 may start at the shoulder of the junction and end at the first end 321.

[0094] The first section 323 may comprise a coupling section 323′ extending over a third length l3. The coupling section 323′ may be defined by the part of the passage 10 between the first end 321 and a shoulder of the passage forming a stop for a flow restrictor of the valve of the pressurized container.

[0095] The second length l2 may be less than 10 mm, preferably less than 9 mm, more preferably less than 8 mm. The third length l3 may be less than 6 mm, preferably less than 5.5 mm, more preferably less than 5 mm. A fourth length l4 between the second end 322 and one end of the outer duct 243 may be less than 2.5 mm, preferably less than 2.4 mm, more preferably less than 2.3 mm, most preferably less than 2.2 mm.

[0096] Although the principles of the invention have been described above with reference to specific embodiments, it should be understood that this description is merely by way of example and should not be construed as a limitation of the scope of the invention which is defined by the accompanying claims.