CN110709171A

CN110709171A - Fluid product dispensing assembly

Info

Publication number: CN110709171A
Application number: CN201880037611.XA
Authority: CN
Inventors: S·贝朗热
Original assignee: Aptal France Simple Joint Co
Current assignee: Aptal France Simple Joint Co
Priority date: 2017-05-05
Filing date: 2018-05-04
Publication date: 2020-01-17
Anticipated expiration: 2038-05-04
Also published as: FR3065890B1; WO2018203018A1; ES2883631T3; FR3065890A1; CN110709171B; EP3628026A1; BR112019022892A2; EP3628026B1; BR112019022892B1

Abstract

Fluid product dispensing assembly (M) for integration in a fluid product dispensing head mounted on a fluid product container, the fluid product dispensing assembly (M) having a fluid product inlet (13), a dispensing orifice (50) and a fluid product flow path (Cp) between the fluid product inlet (13) and the dispensing orifice (50), the fluid product dispensing assembly (M) further having a valve (3, 20) which selectively shuts off said fluid product flow path (Cp), said valve (3, 20) being open at a determined pressure of the fluid product in the fluid product flow path upstream of the valve (3, 20), characterized in that the fluid product dispensing assembly further has a venting path (Ca) for venting the fluid product container.

Description

Fluid product dispensing assembly

Technical Field

The invention relates to a fluid product dispensing assembly for integration in a fluid product dispensing head mounted on a fluid product container, the fluid product dispensing assembly having a fluid product inlet, a dispensing orifice and a fluid product flow path between the fluid product inlet and the dispensing orifice, the fluid product dispensing assembly further having a valve for selectively shutting off the fluid product flow path, the valve being open at a determined pressure of the fluid product in the fluid product flow path upstream of the valve. A preferred field of application of the invention is the cosmetic, cosmetology or medical field.

Background

In the prior art, document EP0117898, for example, proposes a nebuliser, integrating a fluid product dispensing assembly having a fluid product inlet, a valve sensitive to the pressure of the fluid product, and a nozzle suitable for dispensing a nebulised fluid product. The fluid product under pressure moves the movable part of the valve at the inlet of the dispensing assembly, so that the fluid product can flow in the assembly up to the nozzle where it is sprayed.

Document US4273290 proposes another fluid product dispensing assembly, integrated in a dispensing head. More precisely, the fluid product dispensing assembly is in the form of a nozzle having a swirl chamber and a plurality of swirl passages, and a disc valve acted on by a spring. The pressurized fluid product pushes the disk under the action of the spring, so that the fluid product can flow in the nozzle, reach the vortex channel and the vortex chamber and be discharged in an atomized manner through the dispensing orifice.

Document WO94/27732 also proposes, as is known, a fluid product dispensing assembly in the form of a nozzle in which a core of flexible material is arranged, instead of a valve. The pressurized fluid product deforms the flexible core so that the fluid product can flow to the dispensing orifice.

Thus, in these documents of the prior art, the fluid product dispensing assembly defines a fluid product flow channel extending from the inlet of the dispensing assembly to the dispensing orifice. A valve is disposed in the fluid product dispensing passage and is selectively opened or closed by the pressurized fluid product.

Disclosure of Invention

The present invention is directed to providing an additional function to such fluid product dispensing assemblies. To this end, the invention proposes that the fluid product dispensing assembly also has a venting channel of the fluid product container, so that external air can pass through the fluid product dispensing assembly into the container as the fluid product is expelled from the container. In other words, the fluid product dispensing assembly of the invention allows to control the cross flow of fluid product and outside air, to ensure that the container is always kept at atmospheric pressure.

Advantageously, a valve selectively cuts off said vent passage. Thus, the valve of the fluid product also selectively opens and closes the vent passage, instead of the air or vent valve.

According to a practical and advantageous embodiment, the valve has a movable part which, in the inactive position, simultaneously closes the first lateral opening of the fluid product flow channel and the second lateral opening of the vent channel under the action of the spring, and which, in the open position, releases the two lateral openings under the pressure of the fluid product upstream of the movable part, against the action of the spring. Thus, the movement of the movable part can cover and uncover the first and second side holes, while disconnecting or opening the fluid product flow and vent channels.

Advantageously, the movable part has two piston lips that slide sealingly in a sliding cylinder forming two lateral holes that, in the rest position, close both the first and the second lateral holes. Preferably, in the rest position, the mobile element is sealingly stopped against a radial shoulder of the fluid product flow passage under the action of the spring. Thus, at the fluid product flow passage, double sealability is ensured.

According to an advantageous embodiment, the fluid product dispensing assembly comprises:

a mounting body for being fixedly received in a mounting socket of a dispensing head,

an insert part fixedly received in the mounting body, the insert part forming a sliding cylinder,

a movable part sealingly slidably mounted in the sliding cylinder,

a spring acting between the insertion part and the mobile part to actuate the mobile part in the rest position.

The insert member, together with the spring and the mobile member, can be axially inserted in the mounting body to constitute a fluid product dispensing assembly, which is then fixedly received in the mounting socket of the dispensing head.

Advantageously, the sliding cylinder forms a first lateral hole of the fluid product flow channel, which in the rest position is covered by the mobile part, advantageously being released by the mobile part only after the precompression sealing stroke. The first lateral orifice is connected downstream to a first groove formed by the insert element, which communicates downstream with a dispensing orifice advantageously formed by a nozzle mounted on the insert element. The fluid product dispensing assembly may thus be used as a discharge valve for a pump or a valve. And may even be used as a precompression valve that opens only in response to a certain fluid product pressure threshold.

In another aspect, the sliding cylinder forms a second lateral aperture of the vent passage, which is covered by the movable part in the rest position. Advantageously, the sliding cartridge forms a third lateral hole of the venting channel, which communicates with a second lateral hole when the second lateral hole is released by the mobile part, this third lateral hole being connected to a second groove formed by the insertion part, this second groove opening onto the outside of the fluid product dispensing assembly.

The invention also proposes a fluid product dispensing head with a mounting socket in which the fluid product dispensing assembly described above is fixedly received.

The invention also proposes a fluid product dispenser having a fluid product container and a fluid product dispensing head integrated with the fluid product dispensing assembly described above, the fluid product dispensing head being mounted on the fluid product container.

According to one embodiment, the dispenser may have:

-air-driving means, such as a flexible pear-shaped element, suitable for undergoing elastic compression and relaxation phases, connected to the fluid product inlet of the fluid product dispensing assembly, for supplying a flow of pressurized air through the fluid product flow channel up to the dispensing orifice, during the elastic compression phase, and

a fluid product conduit, also connected to the fluid product inlet of the fluid product dispensing assembly, the fluid product in the fluid product conduit being sucked by the pressurized air flow through the venturi effect so as to dispense the mixture of air and fluid product through the dispensing orifice.

In other embodiments, the fluid product dispensing head may also define a pump chamber and a handle wall that a user may press to pressurize the fluid product in the chamber for forced delivery by the fluid product dispensing assembly of the present invention.

The idea of the invention is to improve the valve type common fluid product dispensing assembly of the fluid product, and add the additional function of controlling the ventilation of the fluid product container. An advantageous embodiment of the invention provides that only one valve can open and close, advantageously simultaneously open and close, the fluid product flow channel and the venting channel.

Drawings

Two embodiments of the invention will now be described in more detail with reference to the accompanying drawings, which are given as non-limiting examples.

FIG. 1 is a vertical cross-sectional view through a first embodiment of a fluid product dispenser according to the present invention;

figures 2 and 3 are highly enlarged views of the dispensing head of the dispenser of figure 1 in the rest position and in the operating position, respectively;

figures 4 and 5 are highly enlarged views of the fluid product dispensing assembly of the invention in the rest position and in the operating position, respectively;

FIGS. 6 and 7 are views similar to FIGS. 2 and 3, respectively, showing a second embodiment of the present invention;

figures 8a and 8b are vertical cross-sectional views through a third embodiment of the dispenser of fluid products in the rest position and in the operating position, respectively, according to the present invention; and

figures 9a to 9e are vertical cross-sectional views through a second embodiment of a fluid product dispensing assembly at various stages.

Detailed Description

First, a fluid product dispenser equipped with a fluid product dispensing assembly M according to the invention is described in general terms with reference to fig. 1.

The fluid product dispenser has two distinct components, namely a fluid product container R and a fluid product dispensing head T.

The fluid product container R may be made of any suitable material, such as glass, plastic, metal, etc. The fluid product container may have any shape, but it is intended to have a through hole in the form of a neck R1. The container R contains a fluid product which may be a perfume, a lotion, a skin cream, a medicament, or the like. The container R and its contents are not critical to the invention.

The fluid product dispensing head T is fixedly and sealingly mounted on the neck R1 of the fluid product container R. The head T has a head body T1 which may be injection/moulded from plastic. The head body T1 has a fixing ring T11 which is engaged with the outside of the neck R1. The securing ring T11 may be a screw ring, a locking ring, a scarf ring, or the like. The head body T1 also has a seat T12 in the fixing ring T11, in which a support T2 is inserted, forming a seat for a ball T21. A dip tube T22 is also connected to the support T2. The dip tube T22 extends within the container R to near the bottom thereof. Above the support T2, the head body T1 forms a fluid conduit T13 connected to the mixing chamber T14. The head body T1 also defines a connecting socket T15 in which is engaged a connector T3 on which is mounted an air drive T4, for example in the shape of a compressible pear-shaped piece. Therefore, the interior of the air driving device T4 communicates with the mixing chamber T14 through the connector T3 engaged in the connecting socket T15. On the other hand, the mixing chamber T14 communicates with the mounting chamber T16, which receives the fluid product dispensing assembly M in the mounting chamber T16. It is also noted that the head body T1 forms a vent channel T17 between the seat T12 and the body R1, connecting the mounting socket T16 with the interior of the container R. The overall structure of the dispensing head T should not be considered as the only structure within the scope of the present invention, which depends in particular on the design of the fluid product dispensing assembly M.

Now, with reference to fig. 2 and 4, fig. 2 and 4 show, respectively, the dispensing head T (without the air actuating device T4) and the fluid product dispensing assembly M in the rest position, i.e. without the air actuating device T4 being subjected to any compression force. As described above, the dispensing assembly M is positioned in the mounting socket T16 while communicating with the mixing chamber T14 and the vent conduit T17.

As shown in fig. 4, the dispensing assembly M has a mounting body 1 fixedly received in a mounting socket T16. The mounting body 1 has an inlet sleeve 12 defining internally a fluid product inlet 13 positioned directly downstream of the mixing chamber T14. The mounting body 1 also forms a vent hole 11. The dispensing assembly M also has an insert 2 which is fixedly received within the mounting body 1. The insert 2 has a sliding cylinder 20, a plug 25 and an annular flange 26, which annular flange 26 surrounds the plug 25, forming an annular space 24 therebetween. The slide cylinder 20 has a cylindrical inner wall and an outer wall which engages with the inner wall of the mounting body 1. The slide cylinder 20 has a plurality of through-holes, i.e., a first side hole 21, a second side hole 27, and a third side hole 28. The insert 2 also forms a fourth side hole 23 at the annular flange 26, so that the fourth side hole 23 is directly in the annular space 24. On the other hand, the insert 2 has an external first groove 22, which connects the first lateral hole 21 with the fourth lateral hole 23. The first groove 22 is fitted to the inner wall of the mounting body 1, thereby forming a guide passage connecting the first hole 21 with the fourth hole 23. On the other hand, the insert 2 forms a second groove 29 that connects the third side hole 28 with the outside. The groove 29 is fitted to the inner wall of the mounting body 1 to form an external air inlet guide passage.

The dispensing assembly M also has a movable part 3, which is substantially H-shaped in cross-section. More precisely, the mobile element 3 has a first annular piston lip 32 and a second annular piston lip 33, designed to slide hermetically inside the sliding cylinder 20. The two

lips

32 and 33 are connected together by a small diameter portion 34 which does not perform a sealing sliding with the slide cylinder 20. The movable part 3 also has a partition wall 31 which prevents any contents from passing through the movable part 3.

The dispensing assembly M also has a spring 4 arranged inside the sliding cylinder 20, bearing on the one hand on the insert 2 and on the other hand through the second piston lip 33 on the partition wall 31 of the movable part 3.

In this embodiment, the dispensing assembly M also has a nozzle 5 which engages in the annular space 24 around the plug 25 within the annular flange 26. The nozzle 5 is of entirely conventional design, with a dispensing orifice 50, a swirl chamber 51, a plurality of swirl passages 52 and a plurality of connecting passages 53. The nozzle may dispense a fluid product in the form of fine droplets. However, other types of nozzles may be devised without departing from the scope of the invention.

Figure 4 shows the dispensing assembly M in the rest position, in which the spring 4 pushes the mobile element 3 against a radial shoulder 14 formed at the downstream end of the fluid product inlet 13. More precisely, the first piston lip 32 is supported by the spring 4 in contact on the radial shoulder 14, forming an annular sealing contact. This annular sealing contact plus the radial annular contact of the first piston lip 32 with the sliding cylinder 20. Thus, a double axial and radial seal is formed, in particular it being noted that the first lateral hole 21 is closed by the mobile element 3, since it is located between the two

piston lips

32 and 33. Therefore, the fluid product inlet 13 cannot communicate with the first side hole 21. On the other hand, it can be seen that the second piston lip 33 closes the second side hole 27, which communicates with the air duct 17 through the hole 11. In summary, the first piston lip 32 cuts off the communication between the fluid inlet 13 and the first lateral hole 21, and the second piston lip 33 isolates the first lateral hole 21, completely closing the second lateral hole 27 in the rest position (fig. 2 and 4).

It can also be said that the fluid inlet 13, the first lateral hole, the first recess 22, the fourth lateral hole 23, the annular space 24, the connecting channel 53, the vortex channel 52, the vortex chamber 51 and the dispensing hole 50, together form a fluid flow channel Cp interrupted by the mobile element 3. On the other hand, it can be said that the second side groove 29, the third side hole 28, the inside of the sliding cylinder, the second side hole 27 and the side hole 11 form an air vent channel Ca, which is interrupted at the second side hole 27 by the movable part 3.

The dispensing assembly M will now be described in the fluid product dispensing phase with reference to fig. 3 and 5. To operate the dispenser, the user grips the air-moving device T4 to compress, creating a flow of pressurized air through the narrow connector and mixing chamber T14. The pressurized air cylinder enters the distribution assembly M through the fluid product inlet 13. This cylinder of pressurized air creates a venturi effect, so that by sucking the fluid product stored in the container R through the dip tube 22, the support T2 pushes the ball T21 and the channel T13, the channel T13 leading to the mixing chamber T14. Thus, the fluid product from the container R is mixed at the mixing chamber T14 with the flow of pressurized air from the air moving device T4. For this purpose, a two-phase mixture of fluid product and air is passed through the fluid product inlet 13. Since the two-phase mixture is a pressurized mixture, the movable member 3 is moved in the slide cylinder 20, compressing the spring 4. Thus, the first piston lip 32 moves sealingly and slidably within the sliding cylinder 20 until it reaches the first side opening 21. The sealing stroke of the movable part 3 defines a pre-compression stroke during which the fluid product flow passage Cp is not yet opened. Therefore, the two-phase mixture must reach a certain pressure threshold in order for the first piston lip 32 to move even beyond the first side hole 21, as shown in fig. 5. Thus, a fluid flow passage Cp is established, connecting the fluid inlet 13 to the first lateral hole 21 through a portion of the sliding cartridge 20. Thus, the fluid product P can flow to the dispensing hole 50, where it is dispensed in the form of a mist. Thus, the movable member 3 is a valve that selectively covers and releases the first side hole 21. It is contemplated that the sliding cylinder 20 forms a valve seat on which the first piston lip 32 sealingly slides.

It should also be noted that the vent passage Ca is also open because the second side hole 27 and the third side hole 28 can communicate. In practice, the two

piston lips

32 and 33 are located on either side of the two

lateral holes

27 and 28, so that the constriction 34 of the mobile element 3 is positioned at its two

lateral holes

27 and 28, thus forming a connecting channel between the two holes. Accordingly, external air may enter the container through the second groove 29, the third side hole 28, the inside of the slide cylinder 20, the second side hole 27, the side hole 11, the vent passage, and between the seat T12 and the neck R1.

As soon as the compression force on the air actuating means T4 is released, the pressure at the fluid product inlet 13 drops and the spring 4 pushes the movable part 3 to the rest position of fig. 4. The fluid product flow channels Cp are again broken and, likewise, the vent channels Ca are broken. It should be noted that the two channels Cp and Ca are simultaneously established and simultaneously disconnected.

Fig. 6 and 7 show a second embodiment of the fluid product dispensing head. The dispensing head T' may be identical or similar in certain respects to the dispensing head of the first embodiment, in particular its entire lower portion forming the retaining ring T11, the seat T12, the support T2, the connecting channel T13, the mounting slot T16 and the vent channel T17. This dispensing head T 'differs from the first dispensing head T, on the contrary, in that it has a flexible dome T5 sealingly mounted on a head body T1' by a fixing flange T51. The flexible dome T5 has an elastically deformable manipulation wall T52 that internally defines a pump chamber T50. When the actuating wall T52 is deformed, as shown in fig. 5, the internal volume of the pump chamber T50 is reduced and the fluid product contained therein is pressurized and forced through the connecting chamber T14' to the fluid product inlet 13 of the dispensing module M. Thus, the fluid product pushes the movable part 3, as shown in fig. 5, so that the fluid product can flow through the dispensing assembly M, nebulizing through the dispensing hole 50. It is clear that, during this dispensing phase, the pressure of the fluid product causes the ball 21 to abut against its seat. As soon as the user releases the pressure on the deformable actuating wall T52, a depression is created inside the chamber T50, causing the mobile element 3 to abut against the radial shoulder 14, lifting the ball T21, so that the fluid product from the container R rises through the dip tube 22, the connecting duct T13, reaching the pump chamber T50.

Fig. 8a and 8b show a "squeeze-bottle" type fluid dispenser, i.e. a fluid container R "with a deformable wall R2, which can be compressed by a user's hand. The dispenser also has a dispensing head T "which is mounted on the opening of the container R" by a securing ring T11. The head T "also has a socket T2" in which is housed one end of a dip tube T22, the dip tube T22 extending in the container R "to near the bottom thereof. The head T "also forms a connecting duct T13 and a connecting chamber T14" upstream of the stem T2 ". This chamber T14 "communicates with a mounting slot T16, which receives a fluid product dispensing assembly M in a mounting slot T16, which is identical to the fluid product dispensing assembly of the previous figures. Finally, head T "has a vent conduit T17, T17 connecting bowl T16 to container R".

The deformable wall R2 is compressed and the fluid product stored in the container R "is forced through the dip tube T22, the connecting channel T13 and the connecting chamber T14" to the inlet 13 of the module M, as shown in fig. 8 b. The assembly M is therefore identical to that described in figures 3, 5 and 7.

This third embodiment is intended to illustrate that the assembly M of the invention can be used for different applications: pear-shaped dispensers, compressible dome-shaped dispensers, or "squeeze bottle" type dispensers.

Fig. 9a shows a fluid product dispensing assembly M with a different design. In practice, this module M' has:

a mounting body 1 'for being fixedly received in a mounting socket of the dispensing head, the mounting body 1' defining a first sliding cylinder 15 'and a second sliding cylinder 16', and defining a first through hole 11', a second through hole 18' and a groove 19 'at the first sliding cylinder 15',

a movable part 2' sealingly slidably mounted in two sliding cylinders 15' and 16 ': the movable member 2 'has two lips 22' and 23 'making a sealing sliding contact in the first slide cylinder 15' and another lip 21 'making a sealing sliding contact in the second slide cylinder 16',

a valve member 3 'fixedly mounted in the movable part 2': the valve member 3 'has a valve lip 31', which bears sealingly against the valve seat 20 'of the movable member 2',

a spring 4 acting between the mounting body 1' and the mobile element 2', which actuates the mobile element 2' in the rest position.

Alternatively, the mounting body 1 may be provided with a nozzle 5' which allows the fine droplet fluid product to be sprayed. The nozzle 5' may have a spray wall with a plurality of spray holes of small diameter (1 to 100 microns).

Note that the suction chamber Cs is formed at the second slide cylinder 16'. The chamber Cs has a variable volume because the movable part 2' performs a sliding movement in the second sliding cylinder 16' together with its valve part 3 '.

When the assembly M 'is not operating (fig. 9a and 9e), the two lips 22' and 23 'are positioned on either side of the through hole 11' to isolate them. On the other hand, the valve lip 31 'bears sealingly against the valve seat 20'.

When the product of pressurized fluid reaches the inlet 13' of the assembly M ', the movable part 2' together with its valve part 3' performs a sliding movement in the sliding cylinder 16', as shown in fig. 9b, so that the two holes 11' and 18' communicate with each other from the inside of the cylinder 15' between the two lips 22' and 23', at the thin portion 24 '. Thus, a vent passage Ca is established through the groove 19', the through-hole 18', the interior of the cylinder 15 'and the through-hole 11'. Thus, external air can be transported along the vent passage Ca to the fluid product container, equalizing the internal pressure.

It should be noted on fig. 9b that the valve lip 31 'is always sealingly supported on its valve seat 20'. Only when the pressure of the fluid product reaches a certain pre-compression threshold value does the valve lip become detached from its valve seat 20', as shown in fig. 9 c. Thus, a fluid product flow passage Cp is established through the inlet 13', the passage 35', the space between the valve lip and its valve seat 20', the suction chamber Cs and the nozzle 5'. It should be noted that the vent channel Ca is also established at this time.

As soon as the pressure of the fluid product drops below a determined precompression threshold, the valve lip 31 'bears sealingly against its valve seat 20', so that the fluid product flow path Cp is interrupted and a vent path Ca is established, as shown in fig. 9d, which is identical to fig. 9 b.

Finally, when the fluid product no longer exerts a pressure on the assembly M ', the assembly M' resumes its rest position, as shown in fig. 9e, which is the same as fig. 9 a. The work cycle is complete.

During this period, the volume of the suction chamber Cs changes: in practice, at rest, the suction chamber volume is at its maximum and, in figures 9b and 9c and 9d, at its minimum. This means that, from fig. 9d to 9e, the suction chamber Cs increases in volume, a low pressure is created in the suction chamber Cs, sucking in the fluid product at the nozzle 5' and thus at least partially discharging. This inhalation is particularly effective using a nozzle with spray micro-holes (1 to 100 microns).

Thus, the assembly M' has multiple functions: fluid product valve, container venting and nozzle discharge. It should be noted that the nozzle discharge function can be implemented independently of the other two functions, with ground protection, in particular in connection with nozzles having spray micro-holes.

By means of the dispensing assembly M, M', outside air can be introduced into the fluid product container via the vent path Ca during the fluid product dispensing stage. In general, it should be noted that the dispensing assembly of the present invention is free of means for pressurizing the fluid product. In practice, the pressurizing member is connected to a dispensing head T in the form of an air-operated device T4, mounted to a dispensing head T' in the form of a flexible dome T5, or to a container R ″ having a deformable wall R2. It can even be said that the dispensing assembly of the invention does not actively participate in the pressurization of the fluid product. It is entirely passive, acting only on the pressurized fluid product supplied at its inlet.

With the dispensing assembly M, M' of the present invention, the pump design can be simplified because the discharge valve is formed by the dispensing assembly. In addition, the assembly M, M' also provides for container venting. Its mounting in the mounting socket T16 is very simple, since it is held in place by friction and even by a fixed profile at the inlet sleeve 12 as long as it is axially engaged.

Claims

1. A fluid product dispensing assembly (M; M ') for integration in a fluid product dispensing head (T; T') mounted on a fluid product container (R), the fluid product dispensing assembly (M; M ') having a fluid product inlet (13; 13'), a dispensing orifice (50) and a fluid product flow channel (Cp) located between the fluid product inlet (13; 13') and the dispensing orifice (50), the fluid product dispensing assembly (M; M') further having a valve (3, 20; 3', 2') selectively shutting off said fluid product flow channel (Cp), said valve (3, 20; 3', 2') being open at a determined pressure of the fluid product in the fluid product flow channel (Cp) upstream of the valve (3, 20; 3', 2'),

characterized in that the fluid product dispensing assembly also has a venting channel (Ca) for venting the fluid product container (R).

2. The fluid product dispensing assembly (M; M ') according to claim 1, wherein a valve (3, 20; 3', 2') selectively cuts off the venting channel (Ca).

3. A fluid product dispensing assembly (M) according to claim 2, wherein the valve (3, 20) has a movable part (3) which, in an inoperative position, simultaneously closes the first lateral hole (21) of the fluid product flow channel (Cp) and the second lateral hole (27) of the vent channel (Ca) under the action of the spring (4), and, in an open position, releases both the first lateral hole (21) and the second lateral hole (27) under the pressure of the fluid product upstream of the movable part (3), against the action of the spring (4).

4. A fluid product dispensing assembly (M) according to claim 3, wherein the movable part (3) has two piston lips (32, 33) which slide sealingly in a sliding cylinder (20) which forms the two side holes (21, 27), the two piston lips (32, 33) closing the two side holes, the first side hole (21) and the second side hole (27), in the rest position.

5. A fluid product dispensing assembly (M) according to claim 3 or 4, wherein the movable part (3) in the rest position, under the action of the spring (4), sealingly stops against a radial shoulder (14) of the fluid product flow path (Cp).

6. The fluid product dispensing assembly (M) according to any one of the preceding claims, characterized in that it has:

-a mounting body (1) for being fixedly received in a mounting socket (T16) of a dispensing head (T, T '; T'),

-an insert part (2) fixedly received in the mounting body (1), the insert part (2) forming a sliding cylinder (20),

-a movable part (3) sealingly slidably mounted in a sliding cylinder (20),

-a spring (4) acting between the insertion part (2) and the movable part (3) to actuate the movable part (3) in the rest position.

7. Assembly (M) for dispensing a fluid product according to claim 6, characterized in that the sliding cartridge (20) forms a first lateral hole (21) of the fluid product flow channel (Cp) which is covered by the mobile part (3) in the rest position, advantageously being released by the mobile part (3) only after the pre-compression sealing stroke.

8. Assembly (M) for dispensing fluid product according to claim 7, characterized in that the first lateral hole (21) is connected downstream to a first groove (22) formed by the insert (2), this first groove (22) communicating downstream with a dispensing orifice (50) advantageously formed by a nozzle (5) mounted on the insert (2).

9. A fluid product dispensing assembly (M) according to claim 6, 7 or 8, characterized in that the sliding cartridge (20) forms a second lateral hole (27) of the vent channel (Ca), which in the rest position is covered by the movable part (3).

10. Fluid product dispensing assembly (M) according to claim 9, characterized in that the sliding cartridge (20) forms a third lateral hole (28) of the vent channel (Ca) which communicates with the second lateral hole (27) when it is released by the mobile part (3), this third lateral hole (28) being connected to a second recess (29) formed by the insert part (2), this second recess (29) opening onto the outside of the fluid product dispensing assembly (M).

11. Fluid product dispensing assembly (M) according to any one of the preceding claims, characterised in that it is devoid of a fluid product pressurization member.

12. Fluid product dispensing head (T; T') with a mounting socket (T16), characterized in that the mounting socket (T16) fixedly receives therein a fluid product dispensing assembly (M) according to any one of the preceding claims.

13. Fluid product dispenser, characterized in that it has a fluid product container (R) and a fluid product dispensing head (T; T'; T ") according to claim 12 mounted on the fluid product container (R).

14. Fluid product dispenser according to claim 13, characterised in that the fluid product dispensing head (T; T') has a fluid product pressurisation member for pressurising the fluid product.

15. Dispenser according to claim 13, characterised in that the fluid product dispensing head (T) has:

-air-driving means (T4), such as a flexible pear-shaped element, suitable for undergoing elastic compression and relaxation phases, the air-driving means (T4) being connected to the fluid product inlet (13) of the fluid product dispensing assembly (M) for supplying a flow of pressurized air through the fluid product flow path (Cp) up to the dispensing orifice (50) during the elastic compression phase, and

-a fluid product conduit (T13) also connected to the fluid product inlet (13) of the fluid product dispensing assembly (M), the fluid product in the fluid product conduit (T13) being sucked by the pressurized air flow through the venturi effect so as to dispense the mixture of air and fluid product through the dispensing orifice (50).