EP3439791A1

EP3439791A1 - Assembly for dispensing a fluid product

Info

Publication number: EP3439791A1
Application number: EP17721770.0A
Authority: EP
Inventors: Alexandre CHEN
Original assignee: Aptar France SAS
Current assignee: Aptar France SAS
Priority date: 2016-04-08
Filing date: 2017-04-04
Publication date: 2019-02-13
Anticipated expiration: 2037-04-04
Also published as: US10980330B2; WO2017174918A1; FR3049880A1; FR3049880B1; CA3020206A1; CN109070117B; EP3439791B1; US20190116960A1; CN109070117A; JP6936248B2; JP2019520189A; KR20180134371A

Abstract

An assembly for dispensing a fluid product comprising a fluid product reservoir (R), a dispensing member (5) and a dispensing port (62), the fluid product reservoir (R) comprising a piston (42) that can slide in a sealed manner in a slide barrel (41) over a maximum stroke defined between a start position corresponding to a substantially full state of the reservoir and an end position corresponding to a substantially empty state of the reservoir, characterised in that it further comprises detection means (35) arranged on the outside of the fluid product reservoir (R) and capable of remotely detecting a predefined physical property that enters a restricted detection field covering a warning position of the piston that is closer to the end position than to the start position, the piston (42) bearing said detectable predefined physical property, the detection means (35) delivering, in response to the detection of the physical property, at least one warning signal perceptible to a user.

Description

Distribution set

Fluid product

The present invention relates to a fluid dispenser assembly comprising a fluid reservoir, a dispensing member and a dispensing orifice, the reservoir comprising a piston displaceable in leaktight sliding in a sliding barrel on a maximum stroke defined between a position starting point corresponding to a substantially full state of the tank and an arrival position corresponding to a substantially empty state of the tank. Thus, the assembly makes it possible to apply a fluid product to a target such as the skin. The preferred field of application of the present invention is of course that of cosmetics, but may also be that of pharmacy.

In the prior art, there are already many distributors of this type, including a tank with a piston, follower type or pusher. When the tank is empty, the user is simply informed by the non-delivery of fluid after one or more actuations. It is possible to make the tank transparent material, so that the user sees what is left in the tank.

Also known is WO2015 / 170048 which describes a dispensing assembly implementing a reservoir with a follower piston.

Also known are US2012 / 267390, JP2007 / 153415 and US2012 / 267391 which describe the systems that provide a visual indication of the positioning of a follower piston in a sliding shaft. However, these systems are all passive, so the user has to consult the visual indication, but does not receive information.

The object of the present invention is to improve these fluid product distribution assemblies of the prior art by giving the user clear, reliable and perceptible information on the state of filling / emptying of the piston reservoir. To do this, the present invention provides a fluid dispensing assembly comprising a fluid reservoir, a dispensing member and a dispensing orifice, the reservoir comprising a piston displaceable in sliding sliding in a sliding barrel on a maximum stroke defined between a starting position corresponding to a substantially full state of the reservoir and an arrival position corresponding to a substantially empty state of the reservoir, characterized in that it further comprises physical property detection means having a detection field restricted relative to the maximum stroke of the piston, the physical property detection means being disposed outside the fluid reservoir to remotely detect, through the sliding shaft, a determined physical property which enters the field of restricted detection covering a piston warning position that is more pr oche the arrival position than the starting position, the piston bearing said determined physical property detectable, the detection means delivering, in response to a detection of the physical property, at least one alert signal perceptible by a user . Thus, remote sensing technology is used to provide clear, reliable and perceptible information to the user, who therefore does not need to constantly check the state of filling / emptying of the tank.

Advantageously, the sliding shaft is disposed between the piston and the detection means, the sliding shaft does not prevent the detection of the physical property determined by the detection means. In other words, the material constituting the drum is transparent for the detection means and / or the physical property.

The warning position is reached when the piston has made more than 75%, or more than 90%, or even 100%, of its maximum stroke from the starting position. However, one can still consider other additional warning positions, for example half of the maximum stroke of the piston, or a quarter of its race. The piston may, for example, reach several successive warning positions as it moves towards the arrival position, these warning positions being successively detected by the detection means, which advantageously deliver several distinct respective warning signals.

According to an advantageous embodiment, the detection means are mounted on an integrated circuit board. According to a practical embodiment, the fluid reservoir, the dispensing member and the dispensing orifice are formed by a dispenser which is removably insertable into a casing forming an application surface and incorporating the detection means. advantageously mounted on an integrated circuit board, which extends substantially parallel to a plane passing through the fluid reservoir, the dispensing member and the dispensing orifice.

The distribution assembly then has a configuration similar to or identical to that of document WO2015 / 170048.

According to an advantageous aspect, the detection means are positioned in contact with, or in close proximity to, the sliding drum, so as to reduce the distance between them and the piston.

According to one embodiment, the detection means may comprise a magnetic field sensor and the piston is provided with a magnet generating a magnetic field as a determined detectable physical property. The magnet may have a volume less than 40 mm 3, advantageously less than 30 mm 3, and more advantageously still less than 20 mm 3. The magnet may be annular with an outside diameter slightly smaller than the maximum outside diameter of the piston, so that the magnet is close to the sliding barrel.

Alternatively, the piston is made by injection of plastic filled with magnetic particles.

According to another embodiment, the detection means comprise a determined wavelength sensor and the piston emits waves having said determined wavelength. The determined wavelength may for example be red and the piston is at least partially red.

In a common application, the piston is a follower piston that moves when the fluid in the reservoir is in depression. The spirit of the invention lies in remotely detecting the passage of the piston which moves in the tank drum to provide visual and / or sound information to the user on the state of filling / emptying of the tank . Remote sensing can use any technology, such as induction (magnetic field detection or magnetic field disturbance detection), optics (color, reflection, refraction, diffraction), capacitive effect, ultrasound, hall effect, Faraday effect, resistance variation, etc.

The invention will now be described in more detail with reference to the accompanying drawings, giving by way of non-limiting example, an embodiment of the invention.

In the figures:

FIG. 1 is a vertical cross sectional view through a fluid dispensing and application assembly of the invention, substantially on a scale of 1,

FIG. 2 is a greatly enlarged view of the upper part of FIG. 1,

Fig. 3 is a horizontal cross-sectional view along section line A-A of Fig. 2,

FIG. 4 is an exploded perspective view of the distribution and application assembly of the preceding figures,

FIG. 5 is a view similar to that of FIG. 1, in the absence of a fluid dispenser,

FIG. 6 is a vertical cross-sectional view through a fluid dispenser according to the invention,

FIG. 7 is a view from above of the dispenser of FIG. 6,

FIG. 8 is an exploded perspective view of the dispenser of FIGS. 6 and 7,

FIG. 9 is a diagrammatic sectional view through a fluid dispensing and application assembly according to a second embodiment of the invention,

FIG. 10 is an enlarged view of the piston of FIG. 9, and Figures 1 1 and 12 are views similar to Figure 10 for two other embodiments for a piston according to the invention.

We will begin by illustrating the present invention with reference to Figures 1 to 8 which represent a distribution and application set similar to that of WO2015 / 170048, with remote detection in addition. This distribution and application set has an elongated or slender shape that can be similar to that of a pen or a felt. It can also be noted that its cross section is not constant, since it varies from bottom to top significantly. In this case, near its lower end, the dispensing and application assembly has a rather round or circular cross section, while at the level of the AA cutting line, which is rather located near the the upper end, the dispensing and application assembly has an ovoid-shaped cross section (Figure 3). The upper face of the assembly forms an application surface S which has an inclination or slope towards a side.

Referring to Figure 4, we can see the various components of the distribution assembly and application of the invention. It can first be noted that it comprises three distinct main entities, namely a distribution entity D, a reception entity B and an application entity A. The distribution entity D, which is a product distributor fluid, is received, advantageously removably, inside the receiving entity B, which comprises a one-piece receiving body 1 whose interior is hollow. The application entity A is mounted on and in the body 1, advantageously removably. Thus, preferably, the two entities D and A are removably received on and in the body 1 from these two opposite ends 17 and 12, respectively. This is the overall architecture of the distribution and application assembly according to the invention.

In more detail, the body 1 of the receiving entity B is open at its two high ends 12 and 17 in order to accommodate the entities A and D. The lower end 17 is advantageously internally threaded for by screwing a removable bottom 7. The latter has the shape of a small bucket with a bottom wall 73 and a cylindrical side wall 71 whose upper part forms a thread 72 whose pitch corresponds to that of the lower end 17 of body 1. It may be noted that the removable bottom 7 is provided above its lower wall 73 with a piece of elastic material 74, which may be a foam or an elastomer. The removable bottom 7 internally forms a space 70 which communicates upwardly with the interior of the body 1 which itself defines a reception space 1 a. Beyond this reception space 1a, the interior of the body 1 is divided into two compartments 1b and 1c by a partition wall 13. The compartment

1 b extends axially in the extension of the space 1 a, while the compartment 1 c extends laterally, at the level where the body 1 defines its ovoid shape. The lower end of the partition 13 forms a ratchet edge 14 as will be seen below. The body 1 at the compartment 1b is provided with a lateral pusher 15 which is displaceable transversely to the longitudinal axis of the receiving body 1. The displacement of the pusher 15 can be done by pure translation or by elastic deformation. For example, it is possible to overmold the pusher 15 on the receiving body 1 with an elastomeric material. Alternatively, it is also possible to provide a pusher 15 which moves completely independently of the body 1. One can also provide a simple opening in place of the pusher 15. It can also be noted that the partition wall 13 extends to near the high end 12. The receiving body 1 can very simply be made by injection molding of plastic material, or even metal.

The application entity A results here from the combination of an application head 2 and a wave generation module 3. The application head 2, as can be seen in FIGS. 2, comprises an axial housing 22 formed by a cylindrical pipe whose cross section has a complex geometric shape, for example that of a crescent. This housing 22 is connected upwardly to a surface area of application 21 which is here formed with two openings, namely a first opening corresponding to the mouth of the housing 22 and a second opening for the module 3. More specifically, the module 3 comprises an application surface section 31 which closes the corresponding opening of the head 2 so as to complete continuously and smoothly the application surface area 21 of the head 2. In other words, the module 3 fits in the opening of the application head so that the application surface section 31 of the module 3 completes the surface area of application of the head 2 without creating discontinuity, salient or hollow. Consequently, the assembly of the module 3 and the head 2 makes it possible to create an application surface S whose only opening, at this stage, is formed by the mouth of the housing 22. It can be seen in FIGS. 2 that the application surface section 31 extends at the most inclined portion of the application surface S. The application head 2 also comprises a peripheral skirt 23 which fits in the end high 12 of the hollow body 1. On the other hand, the wave generation module 3 extends inside the reception space 1c, and advantageously has a snap-fitting profile 34 adapted to cooperate with the lower edge 14 of the partition wall. In this way, the application entity A can be mounted in a perfectly stable manner on and in the hollow body 1.

The wave generation module 3 makes it possible to generate any type of wave or electromagnetic, vibratory, etc. radiation, such as, for example, visible light, infrared, ultraviolet, or even microwaves, etc. or else ultrasound or mechanical vibrations. Module 3 can also generate heat or cold (thermal waves) to impart a hot or cold effect to skin contact.

The dispensing entity or fluid dispenser D comprises a fluid reservoir 4, a pump 5 and a dispensing nozzle 6, as can be seen more clearly in FIGS. 6 to 8.

The reservoir 4 may for example be in the form of a sliding shaft 41 in which is received a follower piston 42 which is adapted to slide in the shaft 41 as fluid is extracted from the tank. The top of the shaft 41 forms a neck 45. In place of this particular reservoir, one can also imagine a simpler reservoir without variation of useful volume, or a reservoir with a flexible pocket.

The pump 5 comprises a fixing ring 54 enabling it to be mounted on the neck 45 of the tank 4. The pump 5 comprises a pump chamber 50 provided at its lower end with an inlet valve 51, for example in the form of a slit shutter. At its upper end, the pump chamber 50 comprises an outlet valve 52, which may for example also be in the form of a slit shutter. In addition, the pump chamber 50 comprises a lateral actuator 53 which makes it possible to reduce the useful volume of the pump chamber 50 and thus to discharge fluid through the outlet valve 52. The lateral actuator 53 is movable perpendicularly to the longitudinal axis X of the distributor D. The displacement can be done translatively or by elastic deformation. In the embodiment used to illustrate the present invention, the actuator 53 is in the form of a flexible wall of the pump chamber 50 which has been made for example by a bi-injection or overmolding process. The pump 5 can thus be called flexible diaphragm pump, in that it acts directly on a movable wall of the chamber to put the fluid under pressure. At its upper end, the pump 5 forms a mounting well 56 for the dispensing nozzle 6. This mounting well 56 is advantageously provided with keying means 55, for example in the form of a projecting profile or a recess, for imposing the angular orientation of the tip 6 in the well 56.

The dispensing tip 6 thus comprises a mounting heel 65 which is engaged, and advantageously snapped, inside the mounting well 56. The mounting heel 65 comprises a keying profile which fits perfectly in the means of assembly. keying 55 of the well 56, in order to impose the angular orientation of the dispensing nozzle 6 on the pump 5. In this way, the tip is always oriented in the same manner relative to the lateral actuator 53, which extends only to one side of the pump. above this mounting heel 65, the dispensing nozzle 6 forms an insertion appendix 63 whose cross section has a shape corresponding to that of the housing 22 formed by the application head 2. This shape is more clearly visible on Figure 7: it is similar to a shape of a crescent. The side wall of the insertion appendix 63 may be cylindrical, although not circular over its entire height. Alternatively, one or more projecting sealing bead (s) can be provided for sealing inside the housing 22. At its upper end, the appendage 63 forms a substantially flat exit surface 61 which is pierced with a dispensing orifice 62, forming the outlet of an outlet duct 60 which passes through the appendage 63 and the mounting heel 65, as can clearly be seen in FIGS. 2 and 6.

Once the dispensing nozzle 6 mounted on the pump 5, as shown in Figure 6, it can be seen that the outlet valve 51 communicates directly with the outlet conduit 60. Thus, by pressing the lateral actuator 53, reduces the usable volume of the pump chamber 50, and pressurized fluid is forced through the outlet valve 52, where it can flow through the outlet conduit 60 to the dispensing orifice 62 located at the exit surface 61. As soon as the pressure on the lateral actuator 53 is released, the outlet valve 52 closes and the inlet valve 51 opens under the effect of the depression created in the pump chamber 50, thus allowing aspirate fluid from the reservoir 4, whose follower piston 42 then moves to the pump 5.

As can be understood from FIG. 4, the distribution entity of the dispenser D is inserted inside the hollow body 1 through its lower end 17, after removal of the removable bottom 7. The dispenser D is thus inserted axially through the space 1a, then through the space 1b until the dispensing nozzle 6 penetrates inside the housing 22 of the application head 2. As previously explained, it is it is necessary to angularly orient the distributor D so that its insertion appendix 63 engages inside the housing 22. The angular orientation is preferably unique. It is then possible to fully engage the appendix 63 inside the housing 22 until the exit surface 61 reaches the level of the application surface S so as to complete it. This is visible in FIG. 2. It can be seen that the outlet surface 61 perfectly flush with the application surface area 21 of the head 2 so as to complete it. Finally, only the dispensing orifice 62 breaks the continuity of the application surface S. To ensure the full engagement of the appendix 63 in the housing 22, the removable bottom 7 is used, the flexible material 64 it comes into contact with the bottom of the tank 4 to push it upwards, and to seal at the housing 22. It should also be noted in this regard that the lower end of the tank 4 protrudes out of the hollow body 1 when the bottom removable 7 is removed, so that the dispenser can easily be grasped by its reservoir 4 to extract it from the hollow body 1. As a result, the distributor D is removably received inside the hollow body 1 and the head 2. It can also be noted that the imposed angular orientation of the appendix 63 inside the housing 22 makes it possible to arrange the lateral actuator 53 opposite the pusher 15 of the hollow body 1.

In Figure 3, we can see the arrangement of the various components of the dispensing assembly and application of the invention at the level where it has its ovoid shape. It can be seen, for example, that the generation module 3 is received inside the compartment 1c which is delimited by the partition wall 13 which partially surrounds the pump 5, the lateral actuator 53 of which is covered by the lateral pusher 15. It can thus be said that the pump 5 is disposed between the module 3 and the pusher 15 inside the hollow body 1.

With such a design, the application entity A is removably received on and in the receiving entity R. On the other hand, the dispensing entity of the dispenser D is also removably received inside. of the receiving entity R and inside the housing 22 of the application entity A. In this way, the distributor D and the application entity A can be replaced as desired as required. One can for example imagine that a particular distributor distributing a particular fluid product is associated with a particular application entity. It then suffices to mount the two entities A and D in the receiving entity R to form the distribution and application set of the invention. In case it is necessary to replace the entities A and D, this is easily possible by removing them each from the receiving entity R.

It should also be noted that the fluid dispensed by the dispenser D leaves the dispenser only at the application surface S, so that there can not remain fluid within the receiving entity R, once the dispenser is removed. In addition, because the application surface S is perfectly continuous and smooth, it is easily cleaned by friction or wiping. Thus, when a user wants to change the dispenser, it is sufficient for him first to clean the application surface S, then remove the dispenser and replace it with another. No contamination or deposition of fluid product can be observed.

In the embodiment used to illustrate the present invention, the wave generation module 3 forms an application area sector 31. This is only a particular non-limiting embodiment, since it is quite possible to realize the wave generation module 3 without forming a part of the application surface S. The module 3 may for example be associated with the application head 2 just below the application surface S, which will then serve as diffusion means for the waves.

The total independence between the distributor D and the application entity A, except when assembled in the housing 22, allows to completely separate these two entities, so that they can be produced by companies quite different, namely a company specialized in the design of distributors and a company specialized in the design of electronic modules generating waves.

According to the invention, this dispensing assembly is further provided with means for giving an indication or visual and / or audible information to the user of the assembly as to the state of filling / emptying of the reservoir 4. This information can be given on the distribution set or can even be communicated remotely to a smartphone or a computer equipped with a dedicated application or software. In this particular assembly, the follower piston 42 is provided with a magnet M, preferably a permanent magnet, which is secured to the piston by snapping, latching, force insertion, overmolding, etc. In Figures 1, 2 and 6, it can be seen that the magnet M is disposed in a housing 43 formed by the piston 42. The magnet M is in the form of a grain or a small stud, for example. example of cylindrical shape, having a diameter of the order of 2 to 5 mm and a height / thickness of the order of 2 to 4 mm. A volume of 10 mm 3 to 50 mm 3 can be envisaged, with a preference in the order of 40 mm 3, 30 mm 3 and 20 mm 3. It would be advantageous if the attractive force of the magnet M is small enough that the follower pistons 42 do not adhere to each other, in order to facilitate their handling in the assembly lines.

The follower piston 42 is caused to move on a maximum stroke whose initial low position is shown in FIGS. 1 and 6 and an upper end position which is represented in FIG. 2. It can also be said that the piston 42 slides between a starting position corresponding to a substantially full state of the tank and an arrival position corresponding to a substantially empty state of the tank.

Still according to the invention, the module 3 is provided with detection means comprising a magnetic field sensor 35 capable of remotely detecting, in a restricted detection field, the magnetic field generated by the magnet M when it enters this field. Restricted detection field. The sensitivity of the sensor may for example be of the order of 7 Gauss. The magnetic field sensor 35 is disposed in direct proximity or immediate proximity, or even in contact, with the external wall of the sliding drum 41 of the reservoir, so as to reduce the distance between the sensor 35 and the magnet M. The sensor magnetic field 35 is positioned at the axial level of the upper end position of the follower piston 42, so that the magnet M enters the restricted detection field when the follower piston 42 reaches a warning position which is close to the final position high. This alert position is preferably closer to the position final high than the initial low position. One can also provide several alert positions, for example when the piston 42 is halfway, ¾ of its race, 90% of its race and / or 100% of its race. A warning position at ¼ of his race is also possible.

The detection means also comprise warning means, coupled to the magnetic field sensor 35, for delivering a perceptible warning signal visually or audibly. In the case of the distribution assembly of FIGS. 1 to 8, these warning means are in the form of a light source 36, for example of the LED type, visible through a window 16 of the body 1. A sound warning is also possible, replacing or in addition to the light source 36.

According to a practical aspect, the magnetic field sensor 35 and the light source 36 may be mounted on a printed circuit board 37 of the module 3. It may be noted that the integrated circuit board extends substantially parallel to a plane passing through the fluid reservoir, the dispensing member and the dispensing orifice.

Reference will now be made to FIGS. 9 and 10 to describe a second embodiment of the invention. The distribution and application assembly of FIG. 9 is only very schematically represented, but it is possible to identify a reservoir of fluid product R forming a sliding drum 41 inside which a piston P is loaded. by a spring K. Thus, the fluid stored inside the tank R is subjected to a pressure exerted by the piston P biased by the spring K. At its opposite end, the tank R is connected to a distribution valve V which is actuable by means of a pusher 15 '. Thus, the user can press this pusher 15 'to open the dispensing valve V, so that the fluid product stored under pressure in the reservoir R is forced through the open valve and then through an outlet conduit 60', to reach the level of an application surface 21 '. In this distribution assembly, the tank R may also be in the form of a cartridge which is insertable into the dispensing assembly so as to come to connect with the valve of Alternatively, the dispensing valve V may be an integral part of the cartridge.

According to the invention, this distribution assembly is also equipped with a printed circuit board 37 'on which is mounted a wavelength sensor 35', which can for example detect the wavelength corresponding to red. Furthermore, according to the invention, the piston P may be made in part or in full with a red plastic material or coated with a red coating. Thus, when the piston P reaches the restricted detection field of the sensor 35 ', advantageously located near its final position, the sensor 35' sends an alert signal to a buzzer 36 ', possibly mounted on the control card. circuit board 37 '.

Compared with the first distribution assembly of FIGS. 1 to 8, this second distribution assembly is different in that the piston P is not a follower piston, but a pusher piston biased by a force, such as a spring, the sensor is a wavelength sensor, not a magnetic field sensor, and the warning set is audible, not visual.

The piston P is also shown in Figure 10 enlargedly. For example, it is possible to imagine that the outer periphery of the piston P is coated with a color layer, for example red, detectable by the sensor 35 '.

The sensor 35 'is disposed at the end of the stroke of the piston, but it could also be positioned at another location. It is also conceivable to use several sensors 35 'at different P piston warning positions, in order to provide several respective and distinct warning signals. For example, a short tone can be expected when the piston reaches halfway, two short tones when it reaches three-quarters of the race, and a single long tone when it reaches the end of the race.

Referring to Figure 1 1, we see an alternative embodiment for a piston P ', which can be a follower piston or a pusher piston. Its particularity lies in the fact that this piston P 'is made of a plastic material loaded with magnetic particles. Such a piston P 'can very well be implemented in the first embodiment of Figures 1 to 8, replacing the piston 42.

Referring to Fig. 12, another embodiment of a piston P ", which comprises a magnet M 'in the form of a ring or a ring, can be seen. The advantage of an annular magnet M 'resides in the fact that the magnet is closer to the drum 41 of the reservoir and therefore closer to the magnetic field sensor 35. therefore, a lower power magnet can be used.

It goes without saying that a wavelength sensor 35 'can also be implemented in the first embodiment of FIGS. 1 to 8 with the piston P. On the contrary, a magnetic field sensor can be implemented in place of the sensor 35 'in the embodiment of Figure 9. A piston, such as the piston 42, the piston P' or the piston P "can then be used in this second embodiment.

The embodiments which have just been described implement remote detection technologies using the magnetic field or the color. However, other remote sensing technologies may be used, such as induction (magnetic field detection or magnetic field disturbance detection), optics (color, reflection, refraction, diffraction) , capacitive effect, ultrasound, hall effect, Faraday effect, resistance variation, etc. For example, it is possible to provide detection means in the form of a magnetic field disturbance sensor emitting a magnetic field and a piston comprising an element capable of disturbing the magnetic field generated by the magnetic field disturbance sensor. It is also possible to envisage an optical sensor sensitive to the reflection of light produced by reflective particles or a coating worn by the piston.

Thanks to the invention, there is a distribution assembly comprising a reservoir in which a piston moves (follower or pusher), and whose filling / emptying state can be communicated to the user by means of remote detection.

Claims

claims

1. - Fluid dispenser assembly comprising a fluid reservoir (R), a dispensing member (5; V) and a dispensing orifice (62), the fluid reservoir (R) comprising a piston (42; P '; P ") displaceable in leaktight sliding in a sliding drum (41) on a maximum stroke defined between a starting position corresponding to a substantially full state of the reservoir and an arrival position corresponding to a substantially empty state of the reservoir, characterized in that it further comprises physical property detection means (35; 35 ') having a restricted detection field with respect to the maximum stroke of the piston, the physical property detecting means (35; ') being arranged outside the fluid reservoir (R) to remotely detect, through the slide shaft (41), a determined physical property which enters the restricted field of view. t a piston warning position which is closer to the arrival position than the starting position, the piston (42; P; P '; P ") carrying said detectable determined physical property, the detection means (35; 35 ') delivering, in response to a detection of the physical property, at least one alert signal perceptible by a user.

2. - Dispensing assembly according to claim 1, wherein the sliding shaft (41) is disposed between the piston (42; P; P '; P ") and the detection means (35; 35'), the barrel slidably (41) does not prevent the detection of the physical property determined by the detection means (35; 35 ').

3. - Dispensing assembly according to claim 1 or 2, wherein the alert position is reached when the piston (42; P; P '; P ") has performed more than 75%, or more than 90% or even 100% of its maximum stroke from the starting position.

4. - Dispensing assembly according to any one of the preceding claims, wherein the piston (42; P; P '; P ") reaches several successive warning positions as it moves to the arrival position these warning positions being successively detected by the detection means (35; 35 '), which advantageously deliver several distinct respective warning signals.

5. - Dispensing assembly according to any one of the preceding claims, wherein the detecting means (35; 35 ') are mounted on an integrated circuit board (37; 37').

6. - Dispensing assembly according to any one of the preceding claims, wherein the fluid reservoir (R), the dispensing member (5; V) and the dispensing orifice (62) are formed by a distributor (D) which is removably insertable into a housing (B) forming an application surface (S) and incorporating the detection means (35), advantageously mounted on an integrated circuit board (37), which extends substantially parallel to a plane passing through the fluid reservoir (R), the dispensing member (5; V) and the dispensing orifice (62).

7. - Dispensing assembly according to any one of the preceding claims, wherein the detecting means (35; 35 ') are positioned in contact, or in the immediate vicinity, of the sliding shaft 41), so as to reduce the distance between them and the piston (42; P; P '; P ").

8. - Dispensing assembly according to any one of the preceding claims, wherein the detection means (35; 35 ') comprise a magnetic field sensor (35) and the piston (42; P '; P ") is provided with a magnet (M; M') generating a magnetic field as a determined detectable physical property.

9. - Dispensing assembly according to claim 8, wherein the magnet (M) has a volume less than 40 mm3, preferably less than 30 mm3 and more preferably still less than 20 mm3.

10. - Dispensing assembly according to claim 8 or 9, wherein the magnet (Μ ') is annular with an outside diameter slightly smaller than the maximum outside diameter of the piston (42; P'; P "), so that the magnet (Μ ') is close to the sliding shaft (41).

1 1. - Dispensing assembly according to any one of claims 1 to 7, wherein the detection means comprise a magnetic field sensor (35) and the piston (Ρ ') is made by plastic injection charged with magnetic particles.

12. - Dispensing assembly according to any one of claims 1 to 7, wherein the detecting means comprise a specific wavelength sensor (35 ') and the piston (P) absorbs waves having said length of wavelength. determined wave, the determined wavelength is preferably red and the piston (P) is at least partially red.

13. - Dispensing assembly, wherein according to any one of claims 1 to 7, the detection means comprise a magnetic field disturbance sensor emitting a magnetic field and the piston comprises an element capable of disturbing the magnetic field generated by the magnetic field disturbance sensor.

14. A dispensing assembly according to any one of the preceding claims, wherein the piston (42; P; P '; P ") is a follower piston which moves when the fluid in the fluid reservoir (R) is in depression.