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Title:
DEVICE FOR DISPENSING FLUIDS OR MIXTURES
Document Type and Number:
WIPO Patent Application WO/2020/144532
Kind Code:
A1
Abstract:
The present invention concerns a device (1) for dispensing a fluid (L), suited to be coupled with a container (C) holding said fluid (L). The device (1) comprises a collapsible chamber (6) suited to draw, contain and dispense an amount of said fluid (L) and at least partially delimited by a deformable membrane (10) suited to be squeezed to dispense at least one portion of said amount from the collapsible chamber (6). The device (1) comprises locking means (50, 52, 56) suited to maintain the deformable membrane (10) in a fixed squeezed position and release means (80, 84a, 84b, 86a, 86b) suited to release the deformable membrane (10) from the fixed squeezed position.

Inventors:
ZANDONÀ RAFFELE (IT)
Application Number:
PCT/IB2019/061431
Publication Date:
July 16, 2020
Filing Date:
December 30, 2019
Export Citation:
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Assignee:
TAPLAST SRL (IT)
International Classes:
B05B11/00
Foreign References:
EP1818107A22007-08-15
Attorney, Agent or Firm:
ZILIOTTO, Tiziano (IT)
Download PDF:
Claims:
CLAIMS

1. Device (1) for dispensing a fluid (L), said device (1) comprising a supporting structure (2, 4, 5) provided with means (3) for coupling the same with a container (C) holding said fluid (L), and a collapsible chamber (6) associated with said supporting structure (2, 4, 5), said collapsible chamber (6) being suited to draw, contain and dispense an amount of said fluid (L), said device (1) comprising a suction duct (12) suited to allow said collapsible chamber (6) to communicate with said container (C) and a dispensing duct (22) suited to allow said collapsible chamber (6) to communicate with the outside, said collapsible chamber (6) being at least partially delimited by a deformable membrane (10) suited to be squeezed in order to dispense at least one portion of said amount from said collapsible chamber (6), characterized in that it comprises locking means (50, 52, 56) suited to maintain said deformable membrane (10) in a fixed squeezed position and release means (80, 84a, 84b, 86a, 86b) suited to release said deformable membrane (10) from said fixed squeezed position.

2. Device (1) according to claim 1, characterized in that said locking means (50, 52, 56) comprise also obstructing means designed to obstruct said suction duct (12) when said deformable membrane (10) is maintained in said fixed squeezed position.

3. Device (1) according to claim 1 or 2, characterized in that said locking means (50, 52, 56) comprise snap-fitting locking means (50, 52, 56).

4. Device (1) according to any of the preceding claims, characterized in that said release means (80, 84a, 84b, 86a, 86b) comprise cam release means (80, 84a, 84b, 86a, 86b) shaped in such a way that moving said membrane (10) causes said locking means (50, 52, 56) to be released.

5. Device (1) according to any of the preceding claims, characterized in that said supporting structure (2, 4, 5) comprises a first part (4) and a second part (5) connected to said first part (4), said second part (5) being movable with respect to said first part (4) and said deformable membrane (10) being associated with said second part (5), said second part (5) being preferably suited to be rotated with respect to said first part (4).

6. Device (1) according to claims 4 and 5, characterized in that said release means (80, 84a, 84b, 86a, 86b) are shaped in such a way that moving said second part (5) with respect to said first part (4) causes the release of said locking means (50, 52, 56), preferably the rotation of said second part (5) with respect to said first part (4).

7. Device (1) according to claim 5 or 6, characterized in that said dispensing duct (22), said second part (5) and said deformable membrane (10) are made in a single body and are preferably made of PE.

8. Device (1) according to any of the preceding claims, characterized in that it comprises suction valve means (14, 16) suited to regulate the flow of said fluid (L) from said suction duct (12) into said collapsible chamber (6).

9. Device (1) according to any of the preceding claims, characterized in that it comprises dispensing valve means (26) suited to regulate the flow of said dispensed fluid (L) from said collapsible chamber (6) to said dispensing duct

(22).

10. Device (1) according to claim 9, characterized in that said dispensing valve means (26) comprise a flexible edge (26) suited to assume a closed position intended to prevent the passage of fluid (L) from said collapsible chamber (6) into said dispensing duct (22) and an open position intended to allow the passage of fluid (L) from said collapsible chamber (6) into said dispensing duct (22).

11. Device (1) according to any of the preceding claims, characterized in that said deformable membrane (10) comprises an elastically yielding sphere portion associated with said supporting structure (2, 4, 5).

12. Device (1) according to any of the preceding claims, characterized in that said coupling means (3) allow said device (1) to be removably coupled with said container (C).

13. System for dispensing a fluid (L), comprising a container (C) for said fluid

(L) and a device (1) for dispensing said fluid (L), characterized in that said dispensing device (1) is made according to any of the preceding claims.

Description:
DEVICE FOR DISPENSING FLUIDS OR MIXTURES.

TECHNICAL FIELD OF THE INVENTION

The present invention concerns the technical field of the systems for dispensing fluids or mixtures.

More specifically, the present invention concerns a device for dispensing a fluid which is suited to be applied to a container holding the fluid itself, particularly suited to dispense food substances, perfumes or detergents in general.

DESCRIPTION OF THE STATE OF THE ART

The use of dispensing devices with collapsible chamber is known in the sector of systems for dispensing liquid or creamy products, such as food products, soaps, creams, detergents or perfumes, wherein said devices are applied to the container holding said products.

These devices are substantially constituted by a supporting structure provided with means for coupling the device with the neck of the container and by a dispensing unit suited to dispense the fluid held in the container. The dispensing unit is preferably constituted by a collapsible chamber suited to draw and contain an amount of the fluid coming from the container and to dispense a portion of said amount towards a dispensing nozzle.

The fluid is drawn into the collapsible chamber and dispensed through a manual operation performed by the user, who first directly exerts a compressing action with one or more fingers on a deformable membrane that delimits said chamber and then releases it.

During the compression stage, the fluid contained inside the collapsible chamber is dispensed towards the external environment by means of the dispensing nozzle. In the successive release stage, the deformable membrane automatically returns to its non-compressed configuration, drawing into the collapsible chamber an amount of fluid which will remain contained therein, ready for the successive dispensing operation.

The deformable membrane is typically constituted by an elastically yielding and therefore deformable hemispherical element, which is suited to be deformed so that, starting from its initial hemispherical shape, it finally reaches a squeezed configuration, and then returns to its initial hemispherical shape after being released.

A first drawback of these dispensing devices is related to the transport and handling steps that follow its assembly on the container holding the product. During the above-mentioned steps, the deformable membrane can be subjected to inadvertent impacts or deformation, causing the liquid to be undesirably dispensed.

Another drawback of these devices is constituted by the space they occupy, which is due to the hemispherical shape of the deformable membrane. This can make it difficult to store the device or the assembly comprising the container and the device.

Furthermore, even while stored the deformable membrane can be undesirably subjected to a deforming action and consequently cause the liquid to be undesirably dispensed.

Again, storage operations may require that several assemblies comprising the container and the corresponding device are stacked on top of one another, and their weight may deform the deformable membrane in a permanent manner, making it lose part of its elasticity characteristics and irreparably compromising its operation.

It is the object of the present invention to overcome the drawbacks described above.

More specifically, it is a first object of the invention to provide a device for dispensing a fluid with collapsible chamber, which can be transported and handled by the user in a safer manner, avoiding any loss of product.

It is another object of the invention to provide a device for dispensing a fluid with collapsible chamber, which makes it easier and safer to store the device itself once it has been connected to the container holding the product.

SUMMARY OF THE PRESENT INVENTION

The present invention is based on the general consideration according to which it is desirable to provide a device for dispensing a fluid, wherein said device is suited to be connected to a container holding said fluid and can be operated by acting on a deformable membrane provided with locking means suited to maintain the deformable membrane in a fixed squeezed position.

According to a first embodiment of the present invention, the subject of the same is a device for dispensing a fluid, said device comprising a supporting structure provided with means for coupling the device itself with a container holding said fluid and a collapsible chamber associated with said supporting structure and suited to draw, contain and dispense an amount of said fluid, said device comprising a suction duct suited to place said collapsible chamber in communication with said container and a dispensing duct suited to place said collapsible chamber in communication with the outside, said collapsible chamber being at least partially delimited by a deformable membrane suited to be squeezed to dispense at least one portion of said amount from said collapsible chamber, wherein the device comprises locking means suited to maintain said deformable membrane in a locked squeezed position and release means suited to release said deformable membrane from said locked squeezed position.

In a preferred embodiment, the locking means comprise also obstructing means suited to obstruct the suction duct when the deformable membrane is in the locked squeezed position.

Preferably, the locking means comprise snap-fitting locking means.

According to a preferred embodiment, the release means comprise cam release means configured in such a way that moving the membrane causes the locking means to be released.

In a preferred embodiment, the supporting structure comprises a first portion and a second portion connected to the first portion, said second portion being movable with respect to said first portion and said deformable membrane being associated with said second portion, said second portion being preferably suited to be rotated with respect to said first portion.

In a preferred embodiment, the release means are configured in such a way that moving the second portion with respect to the first portion causes said locking means to be released, preferably causes the second portion to be rotated with respect to the first portion.

According to a preferred embodiment, the dispensing duct, the second portion and the deformable membrane are made in a single body and they are preferably made of PE.

Preferably, the device comprises suction valve means suited to regulate the flow of fluid from the suction duct into the collapsible chamber.

Preferably, the device comprises dispensing valve means suited to regulate the dispensing of the fluid from the collapsible chamber towards the dispensing duct. In a preferred embodiment, the dispensing valve means comprise a flexible edge suited to assume a closed position intended to prevent the passage of fluid from the collapsible chamber towards the dispensing duct and suited to assume an open position intended to allow the passage of fluid from the collapsible chamber towards the dispensing duct. Preferably, the deformable membrane comprises an elastically yielding sphere portion associated with the supporting structure.

Preferably, the coupling means allow the device to be removably coupled with the container.

According to a second aspect of the invention, the subject of the same is a system for dispensing a fluid, comprising a container for said fluid and a device for dispensing said fluid made as described above.

BRIEF DESCRIPTION OF THE DRAWINGS

Further advantages, objects and characteristics, as well as further embodiments of the present invention, are defined in the claims and will be illustrated in the following description, with reference to the enclosed drawings; in the drawings, corresponding or equivalent characteristics and/or components of the present invention are identified by the same reference numbers. In particular, in the drawings:

- Figure 1 shows an axonometric view of a first embodiment of the dispensing device which is the subject of the invention when applied to a container;

- Figure 2 shows an exploded view of the system shown in Figure 1 from a first point of view;

- Figure 3 shows an exploded view of the system shown in Figure 1 from another point of view;

- Figure 4 shows an axonometric view of some elements of Figure 2 isolated from the rest;

- Figures 4 A and 4B show an element represented in Figure 4 according to two respective different points of view;

- Figures from 5 to 7 represent the assembly shown in Figure 1 in different configurations according to an advantageous aspect of the present invention;

- Figure 8 shows a top view of the assembly shown in Figure 6;

- Figure 9 shows a sectional view of Figure 8 along line IX-IX;

- Figure 9 A shows an enlarged detail of Figure 9;

- Figure 10 shows a top view of Figure 9 in a different operating position;

- Figure 1 1 shows a sectional view of Figure 10 along line XI-XI;

- Figure 12 shows a top view of the assembly shown in Figure 7;

- Figure 13 shows a sectional view of Figure 12 along line XIII-XIII;

- Figures from 14 to 17 show the operating steps of the system represented in Figure 1 ; - Figures 15A and 16A show enlarged details of the respective Figures 15 and 16;

- Figure 18 shows an axonometric view of a detail of a variant embodiment of the device according to the invention;

- Figure 19 shows a longitudinal sectional view of the detail shown in Figure 18.

DETAILED DESCRIPTION OF THE PRESENT INVENTION

The examples of embodiment of the invention described below are related to a device for dispensing detergent products. It is clear that the proposed solution can be applied also to devices for dispensing perfumes or food products, or any other fluid in general which is drawn from a container and conveyed towards the outside.

The fluid can also be dispensed in the form of spray, on condition that the device is provided with suitable means for the generation of said spray such as, for example, a diffuser element.

An example of embodiment of a device for dispensing fluids, which is the subject of the present invention, and is applied to a container C containing a fluid L to be dispensed, is illustrated in Figure 1, where it is indicated as a whole by the numeral 1.

The device 1 comprises a supporting structure 2 provided with coupling means 3 for coupling the device itself with the container C. Said coupling means 3 are preferably constituted by a threaded portion 3a, visible in Figure 2, suited to be engaged in a corresponding threaded portion Cf present on the neck of the container C.

In variant embodiments, said coupling means can be of a different type, for example they can be snap-fitting coupling means.

In general, the coupling means are preferably made in such a way as to allow the device to be removably coupled with the container.

The supporting element 2 is preferably made in two parts, a lower part 4 (first part) and an upper part 5 (second part), suited to be associated with each other with a snap-in action and better illustrated in Figure 4.

Furthermore, the upper part 5 is associated with the lower part 4 in such a way that the upper part 5 can be moved with respect to the lower part 4, preferably in such a way that the upper part 5 can rotate by a predetermined angle with respect to the lower part 4.

In the present embodiment, as is better described below, the upper part 5 can rotate by an angle of 90° with respect to the lower part 4. A collapsible chamber 6 is defined between the lower part 4 and the upper part 5 of the supporting element 2, and is suited to draw, contain and dispense an amount of fluid L, as is better described below.

The collapsible chamber 6 is delimited at its bottom by a surface 8, preferably in the shape of a truncated cone, of the lower part 4 and is delimited at its top by a deformable membrane 10.

The deformable membrane 10 is preferably made in a single body with the upper part 5.

The device 1 comprises a suction duct 12 suited to place the collapsible chamber 6 in communication with the container C.

Preferably, the suction duct 12 is partially defined in the lower part 4 of the supporting element 2 and furthermore it preferably comprises a small tube 13 in a predetermined length which is suited to substantially reach the bottom of the container C.

At the level of the lower area of the collapsible chamber 6 there are suction valve means 14 arranged between the collapsible chamber 6 and the suction duct 12 and suited to regulate the flow of the fluid L in the collapsible chamber 6.

The suction valve means 14 preferably comprise a sphere 16 accommodated in a housing portion 18 obtained in the lower part 4 of the supporting structure 2. Inside said housing portion 18 the sphere 16 can be arranged in different positions in order to allow the suction duct 12 to be selectively opened and closed during the operation of the device 1, as will be better explained in the rest of the description.

The device 1 comprises a dispensing duct 22 suited to place the collapsible chamber 6 in communication with the outside and to dispense the fluid L towards the outside of the device 1 and thus towards the outside of the container C.

Preferably, the dispensing duct 22, the upper part 5 and the deformable membrane 10 are made in a single body, more preferably they are made of PE. The dispensing duct 22 is associated with an anti-dispensing safety system 30 comprising a nozzle 32 which is preferably hinged to the upper part 5 of the supporting element 2. The nozzle 32 can assume a first anti-dispensing position, in which it is folded in such a way as to fold and throttle the dispensing duct 22, as shown for example in Figured, and a second position, in which the nozzle 32 is rotated and the dispensing duct 22 is free and can dispense the fluid, as shown in Figures 6 and 7. Figures 18 and 19 show a variant embodiment of the anti-dispensing safety system 130 which comprises holding means 160 suited to maintain the nozzle 132 in the folded position.

The holding means 160 preferably comprise mechanical interference means comprising a projecting element 162 made on the upper part 5 of the supporting structure 2 and a slit 164 made in the lower part of the nozzle 132. The projecting element 162 is suited to be snap-fitted in the slit 164.

Advantageously, when the nozzle 132 is brought in the folded position, the holding means 160 maintain the nozzle 132 in that position safely, as shown in Figure 19.

At the moment of use of the device 1, the user must release the nozzle 132 by rotating it and arranging it in the horizontal position.

At the level of the top of the collapsible chamber 6 there are dispensing valve means 24 arranged between the collapsible chamber 6 and the dispensing duct 22 and suited to regulate the outflow of the fluid L from the inside of the collapsible chamber 6 towards the dispensing duct 22 and thus towards the outside.

The dispensing valve means 24 preferably comprise a flexible edge 26 belonging to the lower part 4 of the supporting element 2 and suited to assume a closed position intended to prevent the passage of fluid L from the inside of the collapsible chamber 6 towards the outside and an open position intended to allow the passage of fluid L from the inside of the collapsible chamber 6 towards the dispensing duct 22 and thus towards the outside of the container C (as shown, for example, in the detail of Figure 15A and better described below).

The deformable membrane 10, preferably hemispherical in shape, is elastically yielding and therefore deformable.

The deformable membrane 10 is suited to be squeezed to dispense a quantity of fluid L from the collapsible chamber 6.

The operating steps of the device 1 of the invention during its normal use are described below with reference to Figures from 14 to 17.

According to an aspect of the present invention, the device comprises locking means 50 suited to maintain the deformable membrane 10 in a fixed squeezed position.

A fixed squeezed position of the deformable membrane 10 according to the invention is shown in Figures 5, 6 and in Figures 8, 9 and 9A.

The fixed squeezed position of the deformable membrane 10 is a position in which the membrane 10 is arranged before the device 1 is used. Preferably, the deformable membrane 10 is arranged in that position by the manufacturer/assembler immediately after the container C has been filled with the fluid L or is arranged in that position by the manufacturer/assembler of the device 1 which is successively assembled on the container C holding the fluid F. According to an aspect of the present invention, the device 1 furthermore comprises release means 80 suited to release the deformable membrane 10 from the fixed squeezed position.

The free/released position of the deformable membrane 10 is shown for example in Figure 7.

Following the activation of the release means 80, the device 1 can be used normally, as described below.

The locking means 50 according to the preferred embodiment shown and described herein preferably comprise a snap-fitting locking system.

The locking means 50, better visible in Figure 4, preferably comprise a projecting annular edge 52, preferably defined on the external surface of a stem 54 extending from the deformable membrane 10 towards the collapsible chamber 6, and a corresponding recessed annular edge 56, preferably made in a cylindrical seat 58 of the lower part 4 of the supporting element 2.

The projecting annular edge 52 snap fits in the recessed annular edge 56, compressing with a given force the deformable membrane 10 which is thus maintained in the fixed squeezed position.

In variant embodiments, the snap-fitting locking system can be made in a different way, for example with different geometrical shapes of said edges, or inverting the position of the projecting edge with respect to the recessed edge. Preferably, the cylindrical seat 58 of the lower part 4 on which the recessed annular edge 56 is defined is created at the level of the terminal part of the suction duct 12 towards the collapsible chamber 6.

Advantageously, with the deformable membrane 10 in the fixed squeezed position, the stem 54 of the deformable membrane 10 is fitted in the cylindrical seat 58 in such a way as to obstruct the suction duct 12.

Advantageously, the locking means 50, in addition to guaranteeing that the deformable membrane 10 is maintained in the desired squeezed position, guarantee the hydraulic sealing of the suction duct 12, avoiding any leakage of fluid L from the container C. In variant embodiments, however, said hydraulic sealing characteristic may be absent.

The release means 80 according to the preferred embodiment shown and described herein preferably comprise a cam release system.

The locking means 80, better visible in Figures 4, 4A and 4B, preferably comprise two inclined surfaces 84a, 84b obtained at the end of the stem 54 and corresponding inclined surfaces 86a, 86b created in the cylindrical seat 58 of the lower part 4 of the supporting element 2.

When the deformable membrane 10 is in the fixed squeezed position, the inclined surfaces 84a, 84b of the stem 54 and the corresponding inclined surfaces 86a, 86b of the cylindrical seat 58 are in contact with one another. With the deformable membrane 10 in the fixed squeezed position, furthermore, the upper part 5 of the supporting element 2 is arranged with a predetermined orientation with respect to the lower part 4, as shown for example in Figures 5, 6 and 8.

To activate the release means 80, the upper part 5 of the supporting element 2 is rotated with respect to the lower part 4, as can be understood by comparing the Figures from 8 to 13.

In the embodiment illustrated herein, the upper part 5 of the supporting element 2 is rotated by 90° with respect to the lower part 4. In variant embodiments, however, the extent of the rotation can be different.

During the rotation of the upper part 5, the inclined surfaces 84a, 84b of the stem 54 and the corresponding inclined surfaces 86a, 86b of the cylindrical seat 58 interact (cam effect) and the stem 54 is pushed in a direction away from the cylindrical seat 58 together with the deformable membrane 10 or, in other words, the deformable membrane 10 is freed/released from the fixed squeezed position by extracting the projecting annular edge 52 of the stem 54 from the recessed annular edge 56 of the cylindrical seat 58.

Said release of the deformable membrane 10 takes place in the first rotation step of the upper part 5 with respect to the lower part 4, for example after a rotation of approximately 10°.

Once released, the deformable membrane 10, thanks to its elasticity, automatically returns to its totally expanded configuration, ready for normal use, as shown in Figure 13.

At the same time, the movement of the stem 54 away from the cylindrical seat 58 clears the suction duct 12. According to the embodiment described herein, four inclined surfaces are provided to obtain the cam effect. In variant embodiments, however, there may be a different number of inclined surfaces, even one only.

According to the description provided above, advantageously, the locking means 50 make it possible to arrange the deformable membrane 10 in a fixed squeezed position before the device 1 is used. Preferably, as explained above, the deformable membrane 10 is arranged in the fixed squeezed position by the manufacturer/assembler immediately after the container C has been filled with the fluid L, or by the manufacturer/assembler of the device 1.

Advantageously, the liquid is prevented from being undesirably dispensed, especially when the device is transported or handled by the user before it is actually used.

Furthermore, the fixed squeezed position 50 of the deformable membrane 10 reduces the overall dimensions of the device 1, making it easier to store the device 1 or the assembly comprising also the container C. Furthermore, there is no need to worry about the storage position of the assembly, which can also be positioned upside down.

Again, the fixed squeezed position 50 of the deformable membrane 10 makes it possible to store several assemblies made up the container C and the respective device 1, stacked on one another, with no need to worry about the weight deforming the deformable membrane 10 in a permanent manner.

Storage, transport and handling by the user are therefore safe and easier compared to the known systems.

The operating steps of the device 1 of the invention, once the deformable membrane 10 has been released, are described here below with reference to Figures from 14 to 17.

In Figure 14 the device 1 is in a rest condition, ready to be used, with the deformable membrane 10 completely expanded.

In the rest condition shown in Figure 14, it is assumed that fluid L is already present in the collapsible chamber 6, since this is the operating condition that occurs when the device 1 is normally used, except when it is used for the first time and the collapsible chamber is still empty.

Figure 15 shows the first step of operation of the device 1, in which the deformable membrane 10 is squeezed.

The compressing action exerted on the deformable membrane 10 increases pressure inside the collapsible chamber 6 and the flexible edge 26 is deformed, creating an opening towards the dispensing duct 22 (as better illustrated in Figure 15 A).

During said step, the sphere 16 obstructs the suction duct 12, so that the fluid L is compressed and conveyed from the inside of the collapsible chamber 6 only towards the dispensing duct 22.

This situation persists until the deformable membrane 10 reaches its stop position, as shown in Figure 16.

The stop position is preferably defined by the contact of the lower surface 92 of the stem 54 with a reference surface 90 of the lower part 4 of the supporting element 2, as shown in the detail of Figure 16 A. It is obvious that in variant embodiments the stop position can be obtained with different means.

At the end of the compression step, a predetermined quantity of fluid L will be dispensed from the collapsible chamber 6 towards the outside through the dispensing duct 22.

Obviously, the quantity of fluid L dispensed can be smaller if the deformable membrane 10 is released before reaching its stop position.

The step of release of the deformable membrane 10 starts once the fluid L dispensing step has been completed and coincides with the step of suction of the fluid L from the container C, which is intended to refill the collapsible chamber 6 with the quantity of fluid L which will be used for the successive dispensing cycle.

Figure 17 shows the release step, in which the flexible edge 26, among the other things, returns to the position in which it closes the dispensing duct 22.

At the same time the sphere 16, due to the decompression created in the collapsible chamber 6, is sucked upwards, thus opening the suction duct 12 at the top.

The deformable membrane 10 is automatically decompressed thanks to its intrinsic elastic yielding characteristics and the fluid L is drawn from the inside of the container C along the suction duct 12 into the collapsible chamber 6.

Finally, the volume of the collapsible chamber 6 is completely restored and the sphere 16 is arranged again in such a way as to obstruct the suction duct 12, while the device 1 returns to its initial condition, that is, the condition shown in

Figure 14, with the collapsible chamber 6 filled with an amount of fluid L suited to be used for the successive dispensing operation. It has thus been shown that the present invention allows the set objects to be achieved. More specifically, it makes it possible to provide a device for dispensing a fluid which can be transported and handled by the user in a safer manner compared to the systems of the known type.

While the present invention has been described with reference to the particular embodiments shown in the figures, it should be noted that the present invention is not limited to the specific embodiments illustrated and described herein; on the contrary, further variants of the embodiments described herein fall within the scope of the present invention, which is defined in the claims.

For example, the description of the present invention refers to the activation of the deformable membrane carried out directly by the user. In variant embodiments, however, the deformable membrane can be squeezed using auxiliary means, for example using a lever or equivalent means.