WO2014001994A1 - Assembly for aerosol spraying a liquid product contained in a container and related container - Google Patents

Abstract

An assembly (10) for aerosol spraying a liquid product (L) contained in a container comprises a container (20) containing only the liquid (L) to be aerosol sprayed and means (50, 51, 52) for feeding pressurised air (A) into the container (20). The container (20) comprises a case (20a) having a longitudinal axis (X - X), at a top portion of the case (20a) being formed an aperture (28) for feeding the pressurised air (A) into the container (20). The container (20) further comprises, at the top portion, a mixing valve (22) for mixing the liquid product (L) with the pressurised air (A), so as to obtain an aerosol mixture, and a supplying nozzle (24) for supplying the aerosol mixture. The nozzle (24) is mechanically and fluid-dynamically associated with the valve (22). The case is made of plastic material and the aperture (28) has an axis of symmetry that is substantially parallel to the longitudinal axis (X - X). The top portion of the case (20a) comprises a substantially dome-shaped surface (34) and a flattened surface (34a) on which the aperture (28) is formed. The flattened surface (34a) is shaped as a substantially circular segment and it is arranged at a height not greater than that of said substantially dome-shaped surface (34).

Description

Assembly for aerosol spraying a liquid product contained in a container and related container

DESCRIPTION

The present invention relates to an assembly for aerosol spraying a liquid product contained in a container.

The invention further relates to a container of a liquid product to be aerosol sprayed.

Throughout the present description and in the attached claims, the term "aerosol spraying" is used to indicate the creation and the supply of a mixture of micro particles of liquid product dispersed into the air.

Containers for aerosol spraying liquid products such as paints, perfumes, insecticides, detergents, etc. are well known . For example, the so-called "spray cans" of the disposable type are common and widely used. These are cylindrical containers, made from a metal material (typically tinplate) , filled with a mixture of a liquid product (for example paint) and with a liquid propellant consisting of a liquefied gas (for example propane, butane o isobutane) . As an example, in a paint spray can of 400 ml, the aforementioned mixture can be formed by 200 ml of paint and 200 ml of liquid propellant.

The liquid propellant has the purpose of diffusing the liquid product in the form of aerosol.

Aerosol spraying of the liquid product by effect of the liquid propellant occurs at a mixing valve that is purposely provided in the spray can.

Due to the pressure exerted on the aforementioned mixing valve, the liquid propellant returns to the gas state and violently comes out from a supplying nozzle which is purposely provided in the spray can, bringing therewith also the liquid product which it was mixed with. The gas part of the mixture dissolves in the air separating from the liquid part, thus obtaining the aerosol spraying of the liquid product. On the other hand, systems are known for supplying a liquid product in the form of aerosol through supply of pressurised air, such as, for example, the aerographs. In such systems, a dispensing gun is coupled, through a connection hose, with a group for generating pressurised air which is typically arranged at a remote position with respect to the gun. Such a gun is moreover connected to a hose that draws from the container in which there is the liquid product to be aerosol sprayed. When the gun is actuated, a depression which draws the liquid product towards a supplying nozzle is created in the body of the gun, substantially due to the Venturi effect, by the supply of pressurised air. The pressurised air thus expels the liquid product through the supplying nozzle, without any mixing being created upstream of the nozzle itself. The Applicant has focused its attention on those aerosol spraying systems in which containers provided with mixing valves, like for example conventional spray cans, are used. The Applicant has indeed verified that these aerosol spraying systems ensure a constant pressure inside the container and, consequently, a spray that is almost instantaneous with optimal characteristics.

There are however some drawbacks associated with the use of the aforementioned spray cans, related to the use as a propellant of a liquefied gas (for example propane, butane or isobutane) which, as it is known, is extremely inflammable. Moreover, such a propellant can form an explosive mixture with air, especially if it is released in closed or confined areas. There is also the risk of explosion of the spray can, in those cases in which there is a strong overheating which causes a considerable increase in volume and pressure of the propellant. Finally, the user could suffer serious cold injuries, in those cases in which the propellant comes into contact with his eyes and skin.

Spray cans should therefore be handled, transported and stored with certain care.

In order to avoid the aforementioned drawbacks the Applicant has conceived the assembly described in International patent application n° WO 2012/017293. Such an assembly comprises a container of the disposable type containing only the liquid product to be aerosol sprayed and means for feeding pressurised air into the container. The container comprises a case on which an aperture is formed for feeding the pressurised air into the container. At a top portion of the case a mixing valve for mixing the liquid product with pressurised air, so as to obtain an aerosol mixture, and a supplying nozzle for supplying the aerosol mixture are provided. The nozzle is mechanically and fluid-dynamically associated with the valve.

Throughout the description and in the following claims, the term "container" is used to indicate any kind of container for containing a liquid product. It can therefore be a can, a jar, a cartridge, etc. The liquid product can be of any kind, like for example paint, oil, chemical products of various kind, etc. The aforementioned assembly allows to aerosol spray the liquid product contained in the container in an almost instantaneous manner, with a constant pressure and optimal spraying characteristics - in a manner that is completely similar to what occurs in a conventional disposable spray can - without however using any liquid propellant. Therefore the risks related to the flammability of the propellant are advantageously avoided. Moreover, in the aforementioned assembly the keeping of an almost constant level of pressure inside the container while aerosol spraying, and therefore obtaining a spray having the desired characteristics of uniformity, is ensured by the fact that the container continues to be supplied with pressurised air even while aerosol spraying the liquid product. This also allows to provide levels of pressure that are lower than those required in devices in which the supply of the pressurised air occurs only before the step of aerosol spraying, with a consequent advantageous reduction of the size and of the weight of the means especially provided for feeding the pressurised air, which can thus be transported more easily during the aerosol spraying step. Of course, even the cost of the aforementioned means is advantageously low.

The aforementioned assembly allows achieving further important advantages, all described in the international patent application indicated above.

The Applicant has now made further improvements to the aforementioned assembly, especially in order to reduce production costs.

The present invention, in a first aspect thereof, thus relates to an assembly for aerosol spraying a liquid product contained in a container, said assembly comprising a container containing only the liquid product to be aerosol sprayed and means for feeding pressurised air into said container, wherein the container comprises a case having a predetermined longitudinal axis, at a top portion of said case an aperture being formed for feeding said pressurised air into the container, wherein said container further comprises, at said top portion of said case:

a valve for mixing said liquid product with said pressurised air so as to obtain an aerosol mixture;

a nozzle for supplying said aerosol mixture, said nozzle being mechanically and fluid-dynamically associated with a said valve,

wherein :

- said case is made of plastic material;

said aperture has an axis of symmetry that is substantially parallel to said predetermined longitudinal axis ;

and wherein said top portion of said case comprises a substantially dome-shaped surface and a flattened surface, said aperture being formed at said flattened surface;

characterised in that said flattened surface is shaped as a substantially circular segment and it is arranged at a height not greater than that of said substantially dome- shaped surface. Advantageously, the assembly of the present invention allows a reduction in the production costs to be achieved due to the fact that the case of the container is made of plastic material and, thus, it can be obtained by low cost processing (preferably through blow moulding) . Advantageously, the Applicant has found that it is possible to use a case in plastic material with walls having a thickness that is relatively small, due to the fact that the operating pressures are considerably lower than in conventional spray cans. Furthermore, the case in plastic material has the great advantage of allowing the container to be filled with all water-based liquid products (for example, cosmetic products, hair sprays, etc.). This is not allowed with conventional tinplate spray cans. Indeed, tinplate is not suitable for containing these water-based products since they would cause it to oxidise over long periods of time, with obvious negative consequences on the quality of the liquid product contained in the case.

Furthermore, thanks to the fact that the aperture of the case of the container has an axis of symmetry that is substantially parallel to the predetermined longitudinal axis, there is an advantageous increase in productivity. Indeed, the aforementioned orientation of the aperture allows it to be accessed (for example in order to mount a one-way valve thereon) easily directly on the filling line of the containers, by using automated machines. Such machines indeed operate very easily throughh parallel and perpendicular movements with respect to the longitudinal axis of the case. Obvious advantages are also achieved in terms of environment pollution. The containers with case of plastic material according to the invention can indeed be recycled more easily than conventional tinplate spray cans .

Advantageously, the substantially dome-shaped surface allows an increase of the resistant surface to the internal pressure generated by the pressurised air introduced into the container, so as to be able to provide the walls of the top portion with a low thickness. Specifically, the substantially dome-shaped surface is a convex surface, or rather it bulges outwards with respect to the case.

Also the base portion of the case is preferably made with a substantially dome-shaped surface, with the consequent possibility of also reducing the thickness of the walls of the base portion of the case. Specifically, the substantially dome-shaped surface of the base portion is concave, that is it bulges inwards with respect to the case .

Preferably, said flattened surface extends in a plane substantially orthogonal to said longitudinal axis. Making the aperture is thus extremely simple.

Preferably, the aforementioned aperture comprises coupling means for coupling to said means for feeding pressurised air into said container.

Preferably, the assembly according to the invention comprises a one-way valve which can be coupled to said aperture and to said means for feeding pressurised air.

Advantageously, the one-way valve prevents the liquid product from flowing out of the container through the aforementioned aperture. Therefore, the container of the invention can be used in any position, even with the axis of the container inclined with respect to the vertical or it can even be upside down.

In a first preferred embodiment of the assembly of the present invention, the aforementioned means for feeding pressurised air comprise a hose which can be coupled, at a first free end thereof, to said one-way valve and, at an opposite free end thereof, to a group for generating pressurised air which is provided at a remote position with respect to said container, for example the group can be associated to a belt which can be put on by a user or stably positioned at a suitable area.

In a second preferred embodiment of the assembly of the present invention, the aforementioned means for feeding pressurised air comprise a device for generating pressurised air which can be removably coupled to the container and a hose which can be coupled, at a first free end thereof, to said one-way valve and, at an opposite free end thereof, to said device for generating pressurised air, so that, when the device for generating pressurised air is coupled to the container and the hose is coupled to the one-way valve and to the device for generating pressurised air, the assembly forms a self-governing operative unit which can be gripped and moved by the user.

In such a way the user can grip and use the assembly of the present invention as if it were a conventional spray can.

Advantageously, the same group or device for generating pressurised air can be used by the user each time associating thereto a plurality of different containers containing possibly different liquid products, such containers also possibly being of the disposable type. In other words, the containers with the liquid products can be sold separately from the device or group for generating pressurised air, which the user needs to buy only once. Preferably, the aforementioned means for feeding pressurized air are configured to feed pressurised air into said container with a constant pressure both before the opening of said mixing valve and while said mixing valve is opened .

In such a way, the pressure of the air inside the container during the supply remains substantially constant, thus obtaining an optimal, even and homogeneous spray.

Preferably, the assembly according to the invention comprises a button for opening the mixing valve and a switch, which is distinct from the aforementioned button, for activating said means for feeding pressurised air into said container.

In such a way, the introduction of pressurised air into the container can also occur before the start of the aerosol spraying of the liquid product.

In a second aspect thereof, the present invention relates to a container of a liquid product to be aerosol sprayed, comprising a case having a predetermined longitudinal axis, at a top portion of said case being formed an aperture for feeding said pressurised air into the container, in which said container moreover comprises, at said top portion of said case:

a mixing valve for mixing said liquid product with said pressurised air so as to obtain an aerosol mixture; a supplying nozzle for supplying said aerosol mixture, said nozzle being mechanically and fluid-dynamically associated with said valve,

in which:

- said case is made in plastic material;

said aperture has an axis of symmetry that is substantially parallel to said predetermined longitudinal axis ;

and in which said top portion of said case comprises a substantially dome-shaped surface and a flattened surface, said aperture being formed at said flattened surface;

characterised in that said flattened surface has a substantially circular-shaped segment and is arranged at a height that is not greater than that of said substantially dome-shaped surface.

Advantageously, such a container can be used in the assembly of the present invention described above.

Preferably, such a container has, individually or in combination, all the structural and functional characteristics discussed above with reference to the container of the assembly of the present invention and, therefore, it has all the advantages mentioned above.

Further characteristics and advantages of the present invention shall become clearer from the following description of a preferred embodiment thereof, with reference to the attached drawings and given as an indication and not for limiting purposes. In such drawings: figure 1 schematically shows a sectional side view of an assembly for aerosol spraying a liquid product contained in a container, according to a first embodiment of the present invention;

figure 2 schematically shows a side view of a container that can be used in the assembly of figure 1;

figure 2a schematically shows a top plan view of the container of figure 2;

figure 3 schematically shows a perspective exploded view of a device for generating pressurised air that can be used in the assembly of figure 1;

figure 4 schematically shows a partial perspective view of one part of a second embodiment of the assembly of the present invention.

Figures 1, 2, 2a and 3, show a first embodiment of an assembly for aerosol spraying a liquid product contained in a container, in accordance with the present invention. The assembly is wholly indicated with reference numeral 10, whereas the container is indicated with reference numeral 20. The liquid product is indicated with L, and it has a free surface P.

In the preferred embodiment of the present invention, said liquid product L is a paint. It is however obvious that in the present invention any other type of liquid product can be used.

The container 20 comprises a case 20a that has a predetermined longitudinal axis X - X and that is made in plastic material, for example in high-density polyethylene (abbreviated with the acronym HDPE) .

The container 20 is provided, at a top portion of said case 20a, with a mixing valve 22 that is fluid-dynamically and mechanically coupled with a supplying nozzle 24. The latter is in fluid communication with the liquid product L through a suction hose 26.

An aperture 28 is formed on the top portion of the case 20a of the container 20. Such an aperture 28 is located at a portion of container 20 that is spatially distinct from that in which the valve 22 and the nozzle 24 are provided.

The aperture 28 is placed above the free surface P of the liquid product L contained in the container 20, when the container 20 is in a vertical supplying position, i.e. it is arranged as illustrated in figures 1 and 2. More precisely, the container 20 illustrated in the non limiting example of figures 1, 2 and 2a substantially has the shape of a conventional spray can. It thus has a cylindrical body 30 that is closed at the bottom by a bottom surface 32 and at the top by a substantially dome- shaped surface 34. The bottom surface 32 is concave, i.e. it bulges inwards with respect to the case 20a, and the substantially dome-shaped surface 34 is convex, i.e. it bulges outwards with respect to the case 20a. At the top of the substantially dome-shaped surface 34 a seat 38 is provided, in which the valve 22 and the nozzle 24 are arranged, both absolutely identical to those used in conventional spray cans. The valve 22 can be made to open by pressing a button 36 located thereon. By releasing the button 36, on which a return spring (not illustrated for the sake of simplicity) acts, the valve 22 closes, just like what occurs in conventional spray cans. In accordance with the present invention, the aperture 28 has an axis of symmetry that is substantially parallel with respect to the predetermined longitudinal axis X - X. In particular, the aperture 28 is defined at a tubular portion 29 which extends from the top portion of the case 20a outwards with respect to the case 20a with an axis of symmetry that is parallel to the longitudinal axis X - X of the case 20a.

As shown in figures 1, 2, 2a and 3, the aperture 28 is formed on a flattened surface 34a of the top portion of the case 20a. The flattened surface 34a extends in a plane that is substantially orthogonal to the longitudinal axis X - X. In particular, the tubular portion 29 of the aperture 28 extends from such a flattened surface 34a of the top portion. The flattened surface 34a is shape substantially as a circular segment and it is arranged at a height that is not greater than that of said substantially dome-shaped surface (34), as clearly shown in figure 2a.

The flattened surface 34a, illustrated in the example of figures 1, 2 and 2a, is located alongside the seat 38 housing the valve 22 and the nozzle 24. Advantageously, since the aperture 28 is provided in a separate position with respect to that of the nozzle 24, it is possible to obtain the desired aerosol spraying effect in the spray, differently from what occurs in devices that operate similarly to the aerographs. In non operating conditions, the aperture 28 is closed by a special lid (not illustrated) .

The tubular portion 29 of the aperture 28 comprises a coupling area 29a, which in the non limiting example of figures 1 and 2 is externally threaded. In this case, in non operating conditions, the lid is preferably screwed onto the coupling area 29a.

In operating conditions, a one-way valve 40 is coupled to the aperture 28, in particular to the coupling area 29a of the tubular portion 29, through screwing of respective matching threaded portions.

In addition to the aforementioned container 20, the assembly 10 of the present invention comprises a device 50 for generating pressurised air A. Such a device 50 is in fluid communication with the container 20 through a hose 52 configured for feeding pressurised air.

According to the invention, a free end 53a of the hose 52 is coupled to the one-way valve 40 mounted on the aperture 28, whereas the opposite free end 53b of the hose 52 is associated to the device 50.

The container 20 and the device 50 comprise respective means 42 for removably associating the device 50 to the container 20 so that the assembly 10 comprising the container 20 and the device 50 for generating pressurised air constitutes a self-governing operative unit that can be gripped and moved by a user.

The aforementioned means 42 preferably allow a mechanical coupling of the generating device 50 to the container 20. In the figures shown herewith, the means 42 comprise a circumferential groove 44 (figure 2) provided on a lower end portion of the cylindrical body 30 of the container 20, therefore at the bottom surface 32, and that snap-couples on an upper surface of the device 50 for generating pressurised air (figure 3) . Alternatively, the aforementioned means 42 are defined elastic hooks.

In the specific embodiment shown in figures 1 and 3, the device 50 comprises a case 56, closed at the bottom by a bottom 58 and on top by a cover 60.

The cover 60 comprises a circular recess 62 in which the lower end portion of the cylindrical body 30 of the container 20 is snap-coupled.

In an alternative embodiment of the present invention, the cover comprises a convex portion, i.e. that bulges outwards from the device for generating pressurised air, and is shaped to match the concave bottom of the container. Such a convex portion can comprise adhesive means that ensure a sufficiently stable coupling with the bottom of the container.

The case 56 of the device 50 contains an air pump 64, an electric motor 66 which actuates the pump 64 and a group 68 for supplying power to the motor 66.

Preferably, the pump 64 is of the diaphragm type, which ensures that the pressure values reguired by the mixing valve 22 are reached so as to achieve the desired aerosol spraying. There are diaphragm pumps currently on the market, which have technical characteristics so as to ensure the use in devices 50 for generating pressurised air according to the present invention. In particular, 2.3 - 2.5 bar diaphragm pumps are for example used, which satisfy the requirements of constancy and regularity of aerosol spraying .

Once it has been actuated, the diaphragm pump rapidly brings the air in the container 20 to the optimal pressure for aerosol spraying (the Applicant has verified that this occurs in about 3 seconds) . For such a purpose the diaphragm pump is equipped with a system of valves on the delivery and suction sections which make it possible to not exceed the predetermined maximum pressure level, even in a condition of continuous use with the nozzle 24 pushed.

The electric motor 66 can be actuated through a switch (not shown) preferably provided on the case 56. The power supplying group 68 preferably comprises batteries of the rechargeable type . Recharging occurs through a conventional recharging device. Preferably, on the device 50 for generating pressurised air an indicator is provided which indicates the level of the battery charge, or rather, it signals when the batteries are almost flat.

As shown in figure 3, the case 56 (or at least one of the bottom 58 and the cover 60) , comprises at least one hole 70 so as to allow the pump 64 to suck in air from the environment. AA hose 72 for emitting pressurised air A, which passes through the case 56 by a special hole 74, is associated to the pump 64.

The hose 72 is in fluid communication with the hose 52 for feeding pressurised air, or alternatively the hose 72 is nothing but an end portion of the hose 52. According to a second embodiment of the invention, the device for generating pressurised air, instead of being associated to the aforementioned container 20, can be a conventional group 51 for generating pressurised air provided at a remote position with respect to the container 20 and connected thereto through a hose 52 for feeding pressurised air. For example, an air compressor, or the compressed air line provided in an industrial factory, can be used.

Figure 4 illustrates a part of a further embodiment of the assembly of the present invention.

In such a figure, structural elements which are equal or corresponding to those described above with reference to figures 1, 2, 2a and 3 are indicated with the same reference numerals and are not described again.

In the embodiment of figure 4, the container (not illustrated) is completely identical to the container 20 of figures 1, 2 and 2a with the sole exception that on the lower end portion of the cylindrical body 30 of the container 20, i.e. at the bottom surface 32, there are no means 42 for coupling to the device 50 for generating pressurised air. Indeed, in the embodiment of figure 4 the device 50 for generating pressurised air is provided, at the bottom 58 thereof, with loops 90 that are suitable for allowing the insertion of a belt 100 which can be put on by the user. In such a way, during use, the user only grips the container 20, whereas the group 51 for generating pressurised air remains anchored to the waist of the user. The group 51 for generating pressurised air is otherwise absolutely identical to the device 50 for generating pressurised air of figures 1 and 3 (although having a different shape and a different arrangement of the components provided therein) , with the single further exception that on the cover thereof (not illustrated) there are no means for coupling to the container 20. In figure 4 it is possible to see the switch (indicated with reference numeral 67) for actuating the electric motor 66. Alongside the switch 67 there are also lights 67a, 67b that are suitable for indicating the actuation of the electric motor 66 and the level of charge of the batteries (that is to indicate when the batteries are almost flat) .

Aerosol spraying the liquid product L initially provides for filling the container 20 with only the liquid product L.

Subsequently, pressurised air A is fed into the container 20 through the aperture 28. One part of such pressurised air A acts upon the free surface P of the liquid product L, whereas a different part directly reaches the mixing valve 22. By opening the valve 22, that is by pressing on the button 36 on the valve 22, the liquid product L goes up towards the mixing valve 22 through the suction hose 26. At such a valve 22 the mixing of the liquid product L with the pressurised air and therefore the aerosol spraying of the liquid product L occurs. The liquid product L can thus be supplied into the outside environment in the form of an aerosol through the nozzle 24.

Preferably, the feeding of pressurised air occurs by associating the device 50 for generating pressurised air to the container 20 beforehand (as described above and as illustrated in figure 3) . Alternatively, the pressurised air is made to come from a group 51 for generating pressurised air provided at a remote position with respect to the container 20 (as for example described with reference to figure 4) .

In the particular embodiment in which the device 50 is coupled with the container 20, the user during operation will grip and move the assembly consisting of the container 20 and the device 50 as if it were a conventional spray can .

In the particular embodiment in which the device 50 is associated with a belt that is put on by the user, the user during operation will only grip the container 20, just as if it were a conventional spray can.

The device 50 can be bought only once by the user, who will then be able to find the relative container 20 on the market with the desired liquid product therein. Such a liquid product will be suitably studied and made so as to give it the best and most suitable chemical-physical characteristics to achieve the desired aerosol spraying. From this point of view, the choice of the mixing valve 22 (and possibly of the supplying nozzle 24) will be made bearing in mind the chemical-physical characteristics of the liquid product L of interest, being able in any case to limit the choice to components already available on the market, since they are used in conventional spray cans.

Of course, a man skilled in the art, with the purpose of satisfying contingent needs and specifications , may carry out numerous modifications and variants to the aforementioned invention, all moreover contained in the scope of protection of the present invention as defined by the following claims .

Claims

1. Assembly (10) for aerosol spraying a liquid product contained in a container, said assembly (10) comprising a container (20) containing only the liquid product (L) to be aerosol sprayed and means (50, 51, 52) for feeding pressurised air (A) into said container (20), wherein the container (20) comprises a case (20a) having a predetermined longitudinal axis (X - X) , at a top portion of said case (20a) an aperture (28) being formed for feeding said pressurised air (A) into the container (20), wherein said container (20) further comprises, at said top portion of said case (20a) :

- a valve (22) for mixing said liquid product (L) with said pressurised air (A) so as to obtain an aerosol mixture; - a nozzle (24) for supplying said aerosol mixture, said nozzle (24) being mechanically and fluid-dynamically associated with said valve (22) ,

wherein :

- said case (20a) is made of plastic material;

- said aperture (28) has an axis of symmetry that is substantially parallel to said predetermined longitudinal axis (X - X) ;

and wherein said top portion of said case (20a) comprises a substantially dome-shaped surface (34) and a flattened surface (34a) , said aperture (28) being formed at said flattened surface (34a) ;

characterised in that said flattened surface (34a) is shaped as a substantially circular segment and it is arranged at a height not greater than that of the substantially dome-shaped surface (34) .

2. Assembly (10) according to claim 1, wherein said flattened surface (34a) extends in a plane substantially orthogonal to said longitudinal axis (X - X) .

3. Assembly (10) according to any one of the previous claims, wherein said aperture (28) comprises coupling means

(29a) for coupling to said means (50, 51, 52) for feeding pressurised air (A) into said container (20) .

4. Assembly (10) according to any one of the previous claims, comprising a one-way valve (40) which can be coupled to said aperture (28) and to said means (50, 51, 52) for feeding pressurised air (A) .

5. Assembly (10) according to claim 4, wherein said means for feeding pressurised air (A) comprises a hose (52) which can be coupled, at a first free end thereof, to said oneway valve (40) and, at an opposite free end thereof, to a group for generating pressurised air (A) which is provided at a remote position with respect to said container (20).

6. Assembly (10) according to claim 4, wherein said means for feeding pressurised air (A) comprises a device (50) for generating pressurised air (A) which can be removably coupled to the container (20) and a hose (52) which can be coupled, at a first free end thereof, to said one-way valve (40) and, at an opposite free end thereof, to said device (50) for generating pressurised air (A) , so that, when the device (50) for generating pressurised air (A) is coupled to the container (20) and the hose (52) is coupled to the one-way valve (40) and to the device (50) for generating pressurised air (A), the assembly (10) forms a self- governing operative unit which can be gripped and moved by the user.

7. Assembly (10) according to any one of the previous claims, wherein said means (50, 51, 52) for feeding pressurised air (A) are configured to feed pressurised air (A) into said container (20) with a constant pressure both before the opening of said mixing valve (22) and while said mixing valve (22) is opened.

8. Assembly (10) according to claim 7, comprising a button (36) for opening the mixing valve (22) and a switch (67), which is distinct from said button (36), for activating said means (50, 51, 52) for feeding pressurised air (A) into said container (20) .

9. Container for a liquid product (L) to be aerosol sprayed, comprising a case (20a) having a predetermined longitudinal axis (X - X) , at a top portion of said case (20a) an aperture (28) being formed for feeding said pressurised air (A) into the container (20) , wherein said container (20) further comprises, at said top portion of said case (20a) :

- a valve (22) for mixing said liquid product (L) with said pressurised air (A) so as to obtain an aerosol mixture;

- a nozzle (24) for supplying said aerosol mixture, said nozzle (24) being mechanically and fluid-dynamically associated with said valve (22);

wherein :

- said case (20a) is made of plastic material;

said aperture (28) has a axis of symmetry that is substantially parallel to said predetermined longitudinal axis (X - X) ;

and wherein said top portion of said case (20a) comprises a substantially dome-shaped surface (34) and a flattened surface (34a), said aperture (28) being formed at said flattened surface (34a) ;

characterised in that said flattened surface (34a) is shaped as a substantially circular segment and it is arranged at a height not greater than that of the substantially dome-shaped surface (34) .