FR3063024A1 - NOZZLE FOR SPRAY SYSTEM - Google Patents

Abstract

The present invention relates to a nozzle (1) for a spraying system (60). The nozzle (1) comprises a first fluid passage (11) allowing a circulation of gas, a second fluidic passage (21) allowing a circulation of liquid and a junction zone (31) between the first fluid passage (11) and the second fluid passage (21) in which the second fluid passage (21) opens through an opening (22). Said opening (22) preferably has the shape of a slot. The nozzle (1) preferably comprises a convergent-divergent portion (41, 42, 43) forming a Laval nozzle, upstream or downstream of the convergent-divergent portion. In addition, the invention relates to a spraying system (60) in which a liquid circuit (80, 62, 21) is pressurized by gas flowing in a gas circuit (70, 61, 11).

Description

Technical area

The present invention relates to a nozzle for a spraying system.

Prior art

Document US2015 / 0129171 A1 discloses a cleaning device in which a liquid is introduced into a flow of gas under pressure to form a jet of fluids at the outlet of the nozzle. One problem with this device is that the liquid is not sufficiently dispersed in the gas flow. At the outlet of the nozzle, all of the fluid does not effectively contribute to cleaning.

Summary of the invention

One of the objects of the invention is to provide a nozzle making it possible to introduce a liquid into a gas flow so as to obtain good dispersion of the liquid in the gas flow.

To this end, according to a first aspect, the invention provides a nozzle for a spraying system comprising:

• a first fluid passage allowing gas circulation, • a second fluid passage allowing liquid circulation, and • a junction zone between the first fluid passage and the second fluid passage in which the second fluid passage opens out through an opening.

In particular, when, according to an optional embodiment of the invention, the opening is a slit, the liquid is distributed over a large part of the section of the gas flow, which allows an even better dispersion of the liquid in the gas flow. This fluid emerging from the nozzle, which forms an aerosol, is characterized by good homogenization of the drops of liquid in the gas. This makes it possible to obtain, at the nozzle outlet, a particularly efficient combined flow of gas and liquid. The inventor has in particular found that the use of a nozzle according to the invention gives excellent results for cleaning applications.

In the context of this document, a slot is an opening extending in two directions, and the extension of which in one direction is at least twice as great as the extension in the other direction, more preferably three times, again more preferably five times, greater than an extension in the other direction. The slot can be for example a rectangle, a rhombus, an ellipse, an oval. The slot makes it possible to have a flow of liquid at the level of the opening which has a fine and elongated shape.

The first fluid passage is preferably separate from the second fluid passage so that the liquid and the gas remain separated up to the junction zone. In other words, they are preferably separated by a part of the nozzle so that they are not partially or completely housed in one another.

The first fluid passage opens into said junction zone, for example, through a first opening and the opening through which the second fluid passage opens into the second fluid passage forms a second opening. The first and second apertures are preferably separate from each other. In other words, they are not partially or totally housed one inside the other.

Preferably, the first and the second opening are arranged so that the flow of liquid leaving the second opening is introduced on a periphery of the flow of gas leaving the first opening. In other words, the second opening does not open into the first fluid passage but at one of its walls.

The junction zone is a part of the nozzle where the first fluid passage and the second fluid passage meet. In one embodiment of the invention, the junction zone is connected by the first opening to one end of the first fluid passage opposite to an inlet of the first fluid passage, and is connected by the second opening to one end of the second fluid passage opposite an entrance to the second fluid passage.

The gas is preferably air. The liquid is preferably water or a cleaning liquid.

For the purpose of this document, a section is the surface taken perpendicular to the direction of fluid flow. For example, the section of a passage is the surface of this passage taken perpendicular to the direction of fluid flow. Similarly, the section of an opening through which a flow passes is the surface of this opening taken perpendicular to the direction of flow of the fluid. In other words, the first opening represents the section of the first fluid passage at the right of the second opening.

Advantageously, the section of the first opening is also of elongated shape, that is to say having an extension in one direction at least twice greater than the extension in the other direction, more preferably three times, again more preferably five times, greater than the extension in the other direction.

Preferably, an extension of said slot in its largest dimension corresponds substantially or is just less than an extension of said first opening in its largest dimension. Said slot is substantially centered along the extension of said first opening in its largest dimension.

According to an embodiment of the invention, a section of the slot or second opening is between 80 and 120% of the section of the first opening.

According to an embodiment of the invention, the first opening is in a first plane and the second opening is in a second plane intersecting in the foreground. In other words, the first and second openings are not parallel. This allows an even better distribution of the liquid in the gas. In particular, an angle between the first plane and the second plane is preferably between 10 ° and 90 °, more preferably between 30 and 90 °.

According to one embodiment of the invention, the nozzle comprises a convergent-divergent part. The converging-diverging part makes it possible to accelerate the fluid, which further improves the efficiency of the jet of fluid leaving the nozzle. The main purpose of the converging-diverging part is not to obtain a suction of the liquid by Venturi effect but to accelerate the fluid.

Preferably, the converging-diverging part forms a Laval nozzle. The Laval nozzle is preferably arranged to accelerate the fluid to a supersonic speed when the fluid outlet opens into the ambient air.

Preferably, the junction zone is not located in the converging-diverging part. For example, if we designate the assembly formed by the first fluid passage and the gas path part junction zone, the second opening may be located at a place where this gas path part has a constant section or at all minus one section causing little or no expansion of the gas.

According to one embodiment of the invention, the diverging convergent part is located in the first fluid passage. The converging-diverging part then accelerates the gas alone, which makes it possible to reach a gas speed at the outlet of the particularly large converging-diverging part.

According to one embodiment of the invention, the divergent convergent part is located in a third fluid passage connecting the junction zone to a fluid outlet. The fluid outlet is the part of the nozzle through which the fluid exits the nozzle. The liquid is then introduced into the gas flow upstream of the converging-diverging part. This allows a particularly good dispersion of the liquid in the gas.

According to one embodiment of the invention, the divergent convergent part comprises a convergent, a neck and a divergent succeeding each other in this order in a flow direction and has a section extending in a first direction and a second direction perpendicular to the first direction, said section having an extension at least five times greater in the first direction than in the second direction at the neck.

Preferably, the extension in the second direction of the section of the converging-diverging part varies by less than 2% along the direction of flow. This allows the converging-diverging part to have a section whose small extension varies little and whose large extension varies clearly to obtain the effect of acceleration of the flux linked to convergence-divergence. In fact, because of manufacturing tolerances, it is preferred to vary the large extension of the section and to keep the small extension of the section approximately constant. For example, the converging-diverging part can have a rectangular section whose length varies but whose width is constant or varies by less than 2%.

According to one embodiment of the invention, the nozzle is arranged so that the first fluid passage can be connected to an orifice of a first conduit and the second fluid passage can be connected to an orifice of a second conduit, the second conduit being at least partially housed in the first conduit and emerging through said orifice of said first conduit. This allows connection of the nozzle with a double conduit comprising a second conduit at least partially housed in a first conduit. This has the particular advantage of simplifying the use of the nozzle because its user must handle only this double conduit, and not two separate conduits, when he wants to use the nozzle.

According to an embodiment of the invention, an inlet of the second fluid passage is located in the first fluid passage or at one end of a cavity of the nozzle intended to receive an end of a first conduit allowing gas to be supplied in the first fluid passage. The inlet of the second fluid passage is the end of the fluid passage through which the liquid is introduced. According to one embodiment of the invention, it is the end opposite to the second opening. These arrangements allow connection with a double conduit. For example, the second conduit, bringing the liquid, can be connected in a leaktight manner with the inlet of the second fluid passage, then the first conduit, bringing the gas, can be connected in a sealed manner with an inlet of the first fluid passage.

According to one embodiment of the invention, the first fluid passage is fluidly connected to a cavity of the nozzle, in particular ribbed and / or threaded, intended to receive one end of a first conduit. This provides a particularly solid connection between the first conduit and the nozzle.

According to one embodiment of the invention, a part of the gas path formed from the first fluid passage and / or from the junction part comprises a bend.

According to one aspect of the invention, said turn is, for example located upstream of the converging / diverging part. This makes it possible to give a different orientation to the gas flow without altering the acceleration of the gas flow by said convergent / divergent part.

According to one aspect of the invention, said turn is, for example, at least 180 °.

According to one aspect of the invention, said bend is configured to give the jet coming out of the nozzle a different orientation, in particular at 90 °, ° relative to the orientation of the conduits serving for the supply of liquid and gas, in particular said double duct, which allows easy manipulation of the nozzle for cleaning on the ground or in spaces with little recoil available, for example.

According to one embodiment of the invention, a part of the gas path formed from the first fluid passage and from the junction part is essentially in a straight line. This allows easy manipulation of the nozzle for cleaning a vertical surface for example.

According to one embodiment of the invention, the nozzle is made in one piece, preferably made by three-dimensional printing, in which the first fluid passage, the second fluid passage and the junction zone are formed in the hollow. This makes the nozzle particularly strong and light. Preferably, the first fluid passage and the second fluid passage are channels in the nozzle.

According to one embodiment of the invention, the nozzle comprises a fluid outlet having a section extending in a first direction and a second direction perpendicular to the first direction, said section having an extension at least five times greater in the first direction than in the second direction. For example, the section of the fluid outlet may be a rectangle having its length at least five times greater than its width.

The invention further provides a spraying system for a pressure cleaning system comprising:

A nozzle which can be a nozzle according to an embodiment of the invention, in particular provided with said slot, or another nozzle, in particular without said slot, • a first conduit connected in a fluid manner, and preferably sealed, at the first fluid passage, and • a second conduit fluidly connected, and preferably sealed, to the second fluid passage.

According to one embodiment of the invention, the second conduit is at least partially housed in the first conduit. The assembly formed by the first and the second conduit can be called double conduit. The first and second conduits can be described as coaxial although they do not necessarily have an axis in the proper sense. The first and second conduits are preferably made of an air impermeable material.

According to one embodiment of the invention, the first conduit is also fluidly connected, and preferably sealed, to a source of pressurized gas and to a liquid reservoir and the second conduit is fluidly connected, and preferably sealed, to the liquid tank. This allows the liquid tank to be pressurized with the gas pressure from the pressurized gas source. An advantage is that the liquid, thus pressurized, circulates in the second conduit to the nozzle. Thus, the nozzle does not need to use the Venturi effect to suck up the liquid. This therefore simplifies the design of the nozzle. In addition, suction by Venturi effect is not very efficient and depends on the positions of the tank and the nozzle. Preferably, the reservoir is a container which is not continuously supplied with pressurized gas but only simultaneously with the supply of gas to the nozzle. In addition, the tank can be portable.

Alternatively, the second conduit is fluidly connected to the liquid reservoir by a third conduit. Preferably, the second conduit is not at all housed in the third conduit.

Advantageously, a distal portion, connected to the nozzle, of the conduits and / or of the double conduit, is rigid and a proximal portion of the conduits and / or of the double conduit, connected to the pressure source and / or to the reservoir is flexible.

The invention further provides a spray method in which the spray system is used in the following manner. The source of pressurized gas is opened to supply pressurized gas to the first conduit so as to pressurize the liquid tank and to supply gas to the first fluid passage of the nozzle, so that the gas pressure in the tank of liquid circulates the liquid from the reservoir in the second conduit to supply liquid to the second fluid passage of the nozzle.

The advantages mentioned for the device apply mutatis mutandis to the method.

Brief description of the figures

Other characteristics and advantages of the invention will appear on reading the detailed description which follows for the understanding of which reference will be made to the appended figures among which:

FIG. 1a illustrates a three-dimensional view of a nozzle in a first embodiment of the invention,

FIG. 1b is a front view of the nozzle according to the first embodiment of the invention,

FIG. 1 c is a side view of the nozzle according to the first embodiment of the invention,

FIG. 1d is a section of the nozzle according to the first embodiment of the invention according to the plane A-A indicated in FIG. 1b,

FIG. 1e is a section on plane B-B indicated in FIG. 1c of the nozzle according to the first embodiment of the invention,

FIG. 2a illustrates a three-dimensional view of a nozzle in a second embodiment of the invention,

FIG. 2b is a front view of the nozzle according to the second embodiment of the invention,

FIG. 2c is a side view of the nozzle according to the second embodiment of the invention,

FIG. 2d is a section of the nozzle according to the second embodiment of the invention according to the plane A-A indicated in FIG. 2b,

FIG. 2e is a section along plane B-B indicated in FIG. 2c of the nozzle according to the second embodiment of the invention,

FIG. 3a is a section of the nozzle according to a third embodiment of the invention,

FIG. 3b is a section of the nozzle according to the third embodiment of the invention,

FIG. 4 illustrates a three-dimensional view of part of a nozzle according to an embodiment of the invention, and

- Figure 5 schematically illustrates a spraying system according to one embodiment of the invention.

Modes of Carrying Out the Invention

The present invention is described with particular embodiments and references to figures, but the invention is not limited by these. The drawings or figures described are only schematic and are not limiting.

In the context of this document, the terms "first >> and" second >> serve only to differentiate between the different elements and do not imply an order between them.

In the figures, identical or similar elements may bear the same references.

FIG. 1a illustrates a three-dimensional view of a nozzle 1 in a first embodiment of the invention. FIG. 1a also illustrates the entry of a cavity 14 of the nozzle 1 which is designed to receive an end 91 of a first conduit 61 (visible in FIG. 5).

Figure 1b is a front view of the nozzle 1 according to the first embodiment of the invention. FIG. 1b also illustrates an inlet 13 of a first fluid passage 11 (visible in FIG. 1d) and an inlet 23 of a second fluid passage 21 (visible in FIG. 1d).

Figure 1 c is a side view of the nozzle 1 according to the first embodiment of the invention.

FIG. 1d is a section of the nozzle 1 according to the first embodiment of the invention according to the plane A-A indicated in FIG. 1b. The nozzle 1 comprises a first fluid passage 11 for circulating a gas from the inlet 13 of the first fluid passage 11 to a first opening 12 which causes the first fluid passage 11 to open in a junction zone 31. The nozzle 1 also comprises a second fluid passage 21 for circulating a liquid from the inlet 23 of the second fluid passage 21 to a second opening 22 which causes the second fluid passage 21 to open in the junction zone 31. Said junction zone corresponds to the so the area of the nozzle where the first and second passages converge to meet and allow the flow of liquid to enter the flow of gas. It is not necessarily defined by a volume delimited by edges and may be in the continuity of one of the passages, in particular in the continuity of the first passage, in particular without increasing or decreasing the section of said first passage at l interface with said junction zone.

A third fluid passage 32, for circulating gas and liquid, fluidly connects the junction zone 31 with a fluid outlet 51. The fluid outlet 51 allows an aerosol comprising the liquid dispersed in the gas to sort of the nozzle 1. The dispersion of the liquid in the gas occurs in the junction zone 31 and / or in the third fluid passage 32. The third fluid passage 32 is preferably essentially in a straight line.

The second opening 22 preferably has the form of a slot. Furthermore, preferably, the second opening 22 is not parallel to the first opening 12. In other words, preferably, the first opening 12 is in a first plane and the second opening 22 is in a second plane which is intersecting in the foreground.

In the first embodiment of the invention, a part of the gas path consisting of the first fluid passage 11 and the junction zone 31 comprises a 180 ° turn.

The cavity 14 for receiving the first conduit 61 is preferably threaded, so that the first conduit 61 can be screwed into it. The first conduit 61 is provided for bringing the gas into the nozzle 1. It is connected in a fluid manner, and preferably in a sealed manner, to the inlet 13 of the first fluid passage 11. A second conduit 62 (visible in FIG. 5) provided to bring the liquid into the nozzle 1 is preferably at least partially housed in the first conduit 61. The second conduit 62 is connected in a fluid manner, and preferably in a sealed manner, to the inlet 23 of the second fluid passage 21.

In the first embodiment of the invention, the inlet 23 of the second fluid passage 21 is located in the first fluid passage

11. Thus, the end of the second conduit 62 can project beyond the end of the first conduit 61 to attach to the inlet 23 of the second fluid passage 21 without there being any mixture between the liquid and the gas. upstream of the junction zone 31.

Figure 1e is a section along the plane B-B indicated in Figure 1c of the nozzle 1 according to the first embodiment of the invention. FIG. 1e illustrates in particular a part of the third fluid passage 32. In the first embodiment of the invention, the third fluid passage 32 comprises, from upstream to downstream, a converging part 41, a neck 42 and a divergent part 43 forming a convergent-divergent part which can be a Laval nozzle.

The converging-diverging part has a section extending in a first direction 101 perpendicular to a direction of the flow 103 and in a second direction perpendicular to the first direction 101 and to the direction of the flow 103. Preferably, the section of the part diverging convergent has an extension at least five times greater in the first direction 101 than in the second direction 102 at the neck 42. In addition, preferably, the extension in the second direction 102 of the section of the converging-diverging part varies less than 2% along the direction of flow 103.

FIG. 2a illustrates a three-dimensional view of a nozzle 1 in a second embodiment of the invention. FIG. 2a also illustrates the entry of a cavity 14 of the nozzle 1 which is designed to receive one end of a first conduit 61 (visible in FIG. 5).

Figure 2b is a front view of the nozzle 1 according to the second embodiment of the invention. FIG. 2b also illustrates an inlet 13 of a first fluid passage 11 (visible in FIG. 2d) and an inlet 23 of a second fluid passage 21 (visible in FIG. 2d).

Figure 2c is a side view of the nozzle 1 according to the second embodiment of the invention.

Figure 2d is a section of the nozzle 1 according to the second embodiment of the invention along the plane A-A indicated in Figure 2b. The nozzle 1 comprises a first fluid passage 11 for circulating a gas from the inlet 13 of the first fluid passage 11 to a first opening 12 which causes the first fluid passage 11 to open in a junction zone 31. The nozzle 1 also comprises a second fluid passage 21 for circulating a liquid from the inlet 23 of the second fluid passage 21 to a second opening 22 which causes the second fluid passage 21 to open in the junction zone 31.

A third fluid passage 32, for circulating gas and liquid, fluidly connects the junction zone 31 with a fluid outlet 51. The fluid outlet 51 allows an aerosol comprising the liquid dispersed in the gas to sort of the nozzle 1. The dispersion of the liquid in the gas occurs in the junction zone 31 and / or in the third fluid passage 32. The third fluid passage 32 is preferably essentially in a straight line.

The second opening 22 preferably has the form of a slot. Furthermore, preferably, the second opening 22 is not parallel to the first opening 12. In other words, preferably, the first opening 12 is in a first plane and the second opening 22 is in a second plane which is intersecting in the foreground.

In the second embodiment of the invention, a part of the gas path consisting of the first fluid passage 11 and the junction zone 31 comprises a 180 ° turn.

The cavity 14 for receiving the first conduit 61 is preferably threaded, so that the first conduit 61 can be screwed into it. The first conduit 61 is provided for bringing the gas into the nozzle 1. It is connected in a fluid manner, and preferably in a sealed manner, to the inlet 13 of the first fluid passage 11. A second conduit 62 (visible in FIG. 5) provided to bring the liquid into the nozzle 1 is preferably at least partially housed in the first conduit 61. The second conduit 62 is connected in a fluid manner, and preferably in a sealed manner, to the inlet 23 of the second fluid passage 21.

In the second embodiment of the invention, the inlet 23 of the second fluid passage 21 is located at the end of the cavity 14. Thus, the end of the second conduit 62 can be at the same level as the end of the first conduit 61, so as to be fixed at the inlet 23 of the second fluid passage 21 without there being any mixture between the liquid and the gas upstream of the junction zone 31.

Figure 2e is a section on plane B-B shown in Figure 2c of the nozzle 1 according to the second embodiment of the invention. FIG. 2e illustrates in particular a part of the first fluid passage 11, the junction zone 31 and the third fluid passage 32. We also see there, in dotted lines, the projection of the second opening 22.

In the second embodiment of the invention, the first fluid passage 11 comprises, from upstream to downstream, a converging part 41, a neck 42 and a diverging part 43 forming a converging-diverging part which can be a Laval nozzle.

The converging-diverging part has a section extending in a first direction 101 perpendicular to a direction of the flow 103 and in a second direction perpendicular to the first direction 101 and to the direction of the flow 103. Preferably, the section of the part convergent5 diverging has an extension at least five times greater in the first direction 101 than in the second direction 102 at the neck 42. Furthermore, preferably, the extension in the second direction 102 of the section of the converging part- diverging varies by less than 2% along the direction of flow 103.

The slot 22 opens downstream of the divergent portion of the convergent / divergent part of the gas passage. Downstream of said divergent portion, the nozzle comprises a flare defining said junction zone 31 and said third fluid passage 32. Said flare is configured so as to limit any expansion effect of the gas while leaving the liquid a volume sufficient to disperse in the gas at the right of said slot 22, and downstream. Here, said flaring has a constant dimension in the direction in which the section of the converging / diverging part varies and a dimension linearly increasing in the direction perpendicular to the previous one and to that followed by the gas flow.

Figure 3a is a section through the nozzle 1 according to a third embodiment of the invention. The nozzle 1 comprises a first fluid passage 11 for circulating a gas from the inlet 13 of the first fluid passage 11 to a first opening 12 which causes the first fluid passage 11 to open in a junction zone 31. The nozzle 1 also comprises a second fluid passage 21 for circulating a liquid from the inlet 23 of the second fluid passage 21 to a second opening 22 which opens the second fluid passage 21 in the junction zone 31.

A third fluid passage 32, for circulating gas and liquid, fluidly connects the junction zone 31 with a fluid outlet 51. The fluid outlet 51 allows an aerosol comprising the liquid dispersed in the gas to sort of the nozzle 1. The dispersion of the liquid in the gas occurs in the junction zone 31 and / or in the third fluid passage 32. The third fluid passage 32 is preferably essentially in a straight line.

The second opening 22 preferably has the form of a slot. Furthermore, preferably, the second opening 22 is not parallel to the first opening 12. In other words, preferably, the first opening 12 is in a first plane and the second opening 22 is in a second plane which is intersecting in the foreground.

In the third embodiment of the invention, a part of the gas path consisting of the first fluid passage 11 and the junction zone 31 is essentially in a straight line.

The nozzle 1 also preferably includes a cavity 14 for receiving one end of a first conduit 61 (visible in FIG. 5). It is preferably threaded, so that the first conduit 61 can be screwed into it. The first conduit 61 is provided for bringing the gas into the nozzle 1. It is connected in a fluid manner, and preferably in a sealed manner, to the inlet 13 of the first fluid passage 11. A second conduit 62 (visible in FIG. 5) provided to bring the liquid into the nozzle 1 is preferably at least partially housed in the first conduit 61. The second conduit 62 is connected in a fluid manner, and preferably in a sealed manner, to the inlet 23 of the second fluid passage 21.

In the third embodiment of the invention, the inlet 23 of the second fluid passage 21 is located in the first fluid passage 11. Thus, the end of the second conduit 62 can protrude from the end of the first conduit 61 to be attach to the inlet 23 of the second fluid passage 21 without there being any mixture between the liquid and the gas upstream of the junction zone 31.

Figure 3b is a section of the nozzle 1 according to the third embodiment of the invention. The section plane of Figure 3b is perpendicular to the section plane of Figure 3a. FIG. 3b illustrates in particular a part of the first fluid passage 11, the junction zone 31 and the third fluid passage 32. We also see there, in dotted lines, the projection of the second opening 22.

In the third embodiment of the invention, the first fluid passage 11 comprises, from upstream to downstream, a converging part 41, a neck 42 and a diverging part 43 forming a converging-diverging part which can be a Laval nozzle.

The converging-diverging part has a section extending in a first direction 101 perpendicular to a direction of the flow 103 and in a second direction perpendicular to the first direction 101 and to the direction of the flow 103. Preferably, the section of the part diverging convergent has an extension at least five times greater in the first direction 101 than in the second direction 102 at the neck 42. In addition, preferably, the extension in the second direction 102 of the section of the converging-diverging part varies less than 2% along the direction of flow 103.

FIG. 4 illustrates a three-dimensional view of part of a nozzle 1 according to an embodiment of the invention. This can for example be the second or third embodiment of the invention. FIG. 4 illustrates in particular a part of the first fluid passage 11, a part of the second fluid passage 21, the second opening 22, the junction zone 31, the third fluid passage 32 and the fluid outlet 51.

Whatever the embodiment of the invention, the second opening 22 can be a rectangle forming a slot. This rectangle may have a length perpendicular to the direction of the flow in the first opening 12 and a width parallel to the direction of the flow in the first opening 12.

Whatever the embodiment of the invention, the nozzle 1 is preferably made in one piece, for example manufactured by three-dimensional printing or by machining.

Whatever the embodiment of the invention, the fluid outlet 51 preferably has a section extending in a first direction, for example the direction 101 of FIG. 4, and a second direction perpendicular to the first direction, for example the direction 102 of FIG. 4. It is then preferred that the section of the fluid outlet 51 has an extension at least five times greater in the first direction than in the second direction. For example, the fluid outlet 51 may be of a rectangular section whose length is at least five times the width.

Advantageously, the slot 22 and / or the first opening has the same shape and / or the same dimension ratios as those of the preceding paragraph.

Said nozzle comprises, for example, a collection chamber for the gas and a collection chamber for the liquid, respectively located just downstream of the gas and liquid inlets 13, 23. Said chambers converge or at the very least open into the first passage 11 and said second passage 21, respectively. Downstream, the gas, the liquid and / or the mixture of the gas and the liquid circulate in the nozzle, taking into account the dimensions mentioned above, in the form of blades of fluids.

Advantageously, said inlet 23 for the liquid comprises a calibrated orifice allowing control of the liquid flow rate.

FIG. 5 illustrates a spraying system 60 according to an embodiment of the invention. The spray system 60 comprises a nozzle 2. The nozzle 2 of the spray system 60 is preferably a nozzle according to an embodiment of the invention, but this could be another nozzle.

The spraying system 60 also comprises a first conduit 61 fluidly connected to the nozzle 2. If the nozzle 2 is a nozzle 1 according to one of the embodiments of the invention mentioned above, a first end 91 of the first conduit 61 can be connected to the first fluid passage 11 thereof.

The spraying system 60 also comprises a second conduit 62 fluidly connected to the nozzle 2. If the nozzle 2 is a nozzle 1 according to one embodiment of the invention mentioned above, a first end 92 of the second conduit 62 can be connected to the second fluid passage 21 thereof.

Preferably, the second conduit 62 is at least partially housed in the first conduit 61, in particular coaxially, to form a double conduit. In other words, the second conduit is located in the first conduit. The liquid circulates in the first conduit and the gas circulates between the first conduit and the second conduit. It is also possible that the second conduit 62 exceeds the first conduit 61 by one and / or the other of its ends 81, 91.

In one embodiment of the invention, the first conduit 61 is fluidly connected, and preferably sealed, to a source of pressurized gas 70 and to a liquid reservoir 80 and the second conduit 62 is fluidly connected , and preferably sealed, to the liquid reservoir 80. For example, a third conduit 63 can form a fluidic and sealed junction between the first conduit 61 and the liquid reservoir 80, in particular at the level of a T-connector. Said second conduit 62 passes through the transverse branch of said T-connector. It is also possible for the third conduit 63 to include at least one gas regulation device, such as a pressure regulator 71 or a valve 72.

Preferably, a second end 81 of the first conduit 61, opposite its first end 91, is connected in leaktight manner to an opening of the liquid reservoir 80, so that the gas in the first conduit 61 can pressurize the liquid reservoir 80. Preferably, a second end 82 of the second conduit 82 opens out from the second end 81 of the first conduit 81, so as to be able to immerse in a liquid contained in the liquid reservoir 80.

The tank 80 is closed, air tight. It preferably includes a valve to avoid overpressure.

Preferably, the first conduit 61 comprises a flexible part 65 which is connected to the liquid reservoir 80 and a rigid part 66 which is connected to the nozzle 2.

Said system may include a gun, not shown, for triggering the projection of the fluid mixture. It is located, for example, on the rigid part of the double conduit and makes it possible to control the passage of gas and liquid in the first conduit and the second conduit.

The spray system 60 according to an embodiment of the invention can operate in the following manner. A user opens the source of pressurized gas 70, for example by actuating the valve 72. The gas from the source of pressurized gas 70 spreads in the third conduit 63 then in the first conduit 61 to the liquid reservoir 80. When the gun is actuated, it also spreads in the first conduit 61 to a first fluid passage of the nozzle 2 allowing the circulation of gas. With or without actuation of the gun, this gas enters the liquid reservoir 80 and pressurizes it. The liquid in the liquid reservoir 80 is then put under the pressure of the gas in the first conduit and spreads into the second conduit 62. If the gun is actuated, it also spreads until a second fluid passage of the nozzle 2 allowing the circulation of liquid. In the nozzle 2, the liquid and the gas are brought into contact in a junction zone in which the first fluid passage opens through a first opening and the second fluid passage opens through a second opening, so as to form an aerosol under pressure.

In the absence of the gun, the actuation of the valve 72 serves to control the device by supplying the nozzle with gas and allowing its supply of water by pressurizing the reservoir 80.

In other words, the invention relates to a nozzle 1 for a spraying system 60. The nozzle 1 comprises a first fluid passage 11 allowing a gas circulation, a second fluid passage 21 allowing a liquid circulation and a zone junction 31 in which the first fluid passage 11 opens through a first opening 12 and the second fluid passage 21 opens through a second opening 22. The second opening 22 preferably has the form of a slot. The nozzle 1 preferably comprises a converging-diverging part 41, 42, 43 forming a Laval nozzle. Furthermore, the invention relates to a spraying system 60 in which a liquid circuit 80, 62, 21 is pressurized by gas flowing in a gas circuit 70, 61, 11.

The present invention has been described in relation to specific embodiments, which have a purely illustrative value and should not be considered as limiting. In general, the present invention is not limited to the examples illustrated and / or described above. The use of the verbs "to understand", "to include", "to include", or any other variant, as well as their conjugations, cannot in any way exclude the presence of elements other than those mentioned. The use of the indefinite article "a", "a >>, or of the definite article" le >>, "la >> or" Γ >>, to introduce an element does not exclude the presence of a plurality of these elements. Reference numbers in the claims do not limit their scope.

Claims (18)

Claims 1. Nozzle (1) for spraying system (60) comprising: • a first fluid passage (11) allowing gas circulation, • a second fluid passage (21) allowing liquid circulation, and • a junction zone (31) between the first fluid passage (11) and the second fluid passage (12) in which the second fluid passage (21) opens through an opening (22), characterized in that the second opening (22) is a slot. 2. Nozzle (1) according to claim 1, in which the first fluid passage (11) opens into the junction zone (31) through a first opening (12) and the opening (22) through which the second fluid passage ( 21) opens into the junction zone (31) forms a second opening, and in which the first opening (12) is in a first plane and the second opening (22) is in a second plane intersecting in the foreground. 3. Nozzle (1) according to any one of the preceding claims, comprising a convergent-divergent part (41, 42, 43), the convergent-divergent part (41, 42, 43) preferably forming a Laval nozzle. 4. Nozzle (1) according to the preceding claim, in which the converging-diverging part (41, 42, 43) is located in the first fluid passage (11) or in a third fluid passage (32) connecting the junction zone ( 31) at a fluid outlet (51). 5. Nozzle (1) according to claim 3 or 4, wherein the convergent-divergent part (41,42, 43) comprises a convergent (41), a neck (42) and a divergent (43) succeeding each other in this order in a flow direction (103) and has a section extending in a first direction (101) 5 and a second direction (102) perpendicular to the first direction (101), said section having an extension at least five times greater in the first direction (101) than in the second direction (102) at the neck (42) . 10 6. Nozzle (1) according to the preceding claim, in which the extension in the second direction (102) of the section of the convergent-divergent part (41,42, 43) varies by less than 2% along the direction of flow (103). 15 7. Nozzle (1) according to any one of the preceding claims, arranged in such a way that the first fluid passage (11) can be connected to an orifice of a first conduit (61) and the second fluid passage (21) can be connected to an orifice of a second conduit (62), the second conduit (62) being at least partially housed in the first 20 conduit (61) and opening through said orifice of said first conduit (61). 8. Nozzle (1) according to the preceding claim, wherein an inlet (23) of the second fluid passage (21) is located in the first fluid passage (11) or at one end of a cavity (14) of the nozzle ( 1) planned 25 to receive one end of a first conduit (61) allowing gas to be brought into the first fluid passage (11). 9. Nozzle (1) according to any one of the preceding claims, in which the first fluid passage (11) is fluidly connected to a cavity (14) of the nozzle (1) designed to receive an end of a first conduit (61). 10. Nozzle (1) according to any one of the preceding claims, in which a gas path part formed by the first fluid passage (11) and the joining part (31) comprises a bend at least 180 °. 11. Nozzle (1) according to any one of claims 1 to 9, in which a part of the gas path formed by the first fluid passage (11) and the joining part (31) is essentially in a straight line. 12. Nozzle (1) according to any one of the preceding claims, made in one piece, preferably made by three-dimensional printing, in which the first fluid passage (11), the second fluid passage (22) and the area of junction (31) are hollowed out. 13. Nozzle (1) according to any one of the preceding claims, comprising a fluid outlet (51) having a section extending in a first direction (101) and a second direction (102) perpendicular to the first direction (101 ), said section having an extension at least five times greater in the first direction (101) than in the second direction (102). 14. Spray system (60) for a pressure cleaning system comprising: • a nozzle (1) according to any one of the preceding claims, • a first conduit (61) fluidly connected to the first fluid passage (11), and • a second conduit (62) fluidly connected to the second fluid passage (21). 15. Spray system (60) according to the preceding claim, wherein the second conduit (62) is at least partially housed in the first conduit (61). 16. Spray system (60) according to claim 14 or 15, wherein the first conduit (61) is further fluidly connected to a source of pressurized gas (70) and to a liquid reservoir (80) and the second conduit (62) is fluidly connected to the liquid reservoir (80). 17. Spraying system (60) according to the preceding claim, wherein the second conduit (62) is fluidly connected to the liquid reservoir (80) by a third conduit (63). 18. Spraying process comprising the steps of: • providing a spraying system (60) according to claim 16 or 17, • opening the source of pressurized gas (70) to supply pressurized gas to the first conduit (61) so as to pressurize the liquid reservoir ( 80) and supplying gas to the first fluid passage (11) of the nozzle (1), so that the gas pressure in the liquid tank (80) circulates the liquid from the tank (80) in the second conduit ( 62) to supply liquid to the second fluid passage (21) of the nozzle (1).