EP0972574B1 - Liquid spray nozzle - Google Patents

Abstract

The nozzle comprises a head with an inlet and one or more outlets, each containing a diffuser (4) in the form of a bush (5) with a conical inner cavity containing a conical component (6), and an outlet (8). The conical component has three spiral grooves (14a, 14b, 14c) with their ends at the base of the cone connecting with the interior of the diffuser via separate orifices (15a) at an angle of 120 degrees to one another, and at the tip of the cone meeting a common outlet (8). The inner surface of the bush and outer surface of the cone have matching threads for screwing together.

Description

The invention relates to a nozzle for spraying a liquid, in particular for the fire protection.

For fire protection, it is known to use spray nozzles which generate water mists.

For a good result, we must ensure a sufficient fog density as well good quality regarding the size of the droplets.

In general, we seek to have for each diffusion orifice or spraying, the greatest flow rate while having a very fine droplet size, which increases the efficiency of the fact that extinguishing a fire by this means is due to the heat exchange between the hearth or the fire to be extinguished and said droplets.

In fact, the higher the flow and / or the finer the droplets, the more number of these is important, which in fact increases the surface in contact with the hearth or fire and promotes heat exchange and the evaporation of fine droplets, which accelerates the extinction process.

In addition, each fire risk recommends a suitable system for the shape and nature of the spray mist.

The present invention relates to a spray nozzle which has a head provided with a liquid inlet and at least one orifice forming a housing in which is arranged a diffuser, and more particularly a nozzle with several diffusers to generate a full cone water mist formed by a sum of cones hollow. It will be understood hereinafter what is designated by the words nozzle and diffuser, because the previous literature in the field is not always in harmony on the terms used (nozzle, nozzle, sprayer, ...).

In this prior art, there are known for example devices described in documents GB-180387A, FR-639530A, FR-461464A or US-2.098.487A which contain a single diffuser consisting of a sleeve forming an interior volume which is delimited by a circular cone whose apex facing outward is pierced to constitute a spray orifice, and in which is housed a conical part at least partly hollow, of conjugate external shape and provided externally at least one conical helical groove which extends from the base of said conical part by communicating with the interior thereof, towards its top for forming in combination with the inner wall of said sleeve, a helical channel conical of circulation of the liquid.

To improve these known devices, in particular in guiding the liquid and its arrival at the spray orifice, a nozzle according to the invention is particularly remarkable in that the conical part of the diffuser has three grooves conical helicals whose ends at the base of the part communicate directly inside thereof by a separate orifice, said ends and therefore said orifices being offset angularly two by two by an angle substantially of 120 °, while the other ends of the grooves reach the immediate vicinity from the top of said part after development over substantially one revolution for form a common inlet opposite the spray orifice of the sleeve.

Advantageously, the housing of the nozzle intended for the diffuser has a thread inside intended to cooperate by screwing with a conjugated external thread fitted on the diffuser sleeve, while the conical part of the diffuser is provided at its base with an external thread intended to cooperate by screwing with a thread interior conjugate provided at the base of the sleeve.

According to an interesting embodiment, the conical part of the diffuser is not not completely inserted into the housing formed by the interior volume of the sleeve, thus creating a space between said conical piece and the inner wall of the sleeve by which the helical channels can communicate with each other. This is, by example, obtained by partial tightening of the conical part in the sleeve, or by a particular form of said part.

The nozzle head is generally provided with several housings and in this case an embodiment according to the invention is remarkable in that on the one hand, the angles at the top of the conical pieces and the sleeves of the diffusers and, on the other hand, the diameters of the spray orifices depend on the locations of the diffusers on the head of the nozzle depending on the desired effect.

For example, the head of the nozzle has substantially the shape of a pear, the or the housings for the diffusers being provided on its swollen part while preferably the diffusers have larger spray orifice diameters larger and smaller and smaller angles at the top as their locations approach the larger diameter area of the head of the nozzle.

According to another embodiment, the head of the nozzle has substantially a circular arc shape, the housings for the diffusers being arranged in an arc of circle, their axes being substantially coplanar along a plane passing through the axis of the arrival of the liquid.

It is still possible that the nozzle head has a cylindrical part coaxial with the axis of the liquid inlet, the housings for the diffusers being provided on this cylindrical part, their axes being substantially coplanar according to a plane substantially perpendicular to said axis of the arrival of the liquid or also said head may have a flat part substantially perpendicular to the axis of the inlet liquid, the housings for the diffusers being arranged obliquely by opening in this flat part.

• la figure 1 représente en perspective une buse selon un mode de réalisation de l'invention,
• les figures 2 et 3 sont des coupes selon les lignes respectivement II-II et III-III de la figure 1,
• la figure 4 est une vue en perspective de la pièce conique d'un diffuseur selon l'invention,
• la figure 5 est une vue de dessous de la pièce de la figure 4,
• la figure 6 est une vue en perspective du manchon d'un diffuseur selon l'invention,
• la figure 7 est une vue de dessous du manchon de la figure 6,
• la figure 8 est une coupe longitudinale d'un diffuseur selon l'invention, c'est-à-dire après assemblage des pièces des figures 4 et 6,
• la figure 9 montre une tête de buse comme la figure 1 mais selon une autre forme,
• les figures 10 et 11 sont des coupes selon les lignes respectivement X-X et XI-XI de la figure 9, des diffuseurs étant en outre représentés dans leurs logements,
• la figure 12 montre une autre tête de buse possible,
• la figures 13 est une coupe selon la ligne XIII-XIII de la figure 12, des diffuseurs étant en outre représentés dans leurs logements comme pour les figures 10 et 11,
• les figures 14 et 15 correspondent respectivement aux figures 12 et 13 selon une autre forme, la coupe de la figure 15 étant réalisée selon la ligne XV-XV de la figure 14.

The invention will be clearly understood on reading the description which follows and which refers to the appended drawings in which:

• FIG. 1 represents in perspective a nozzle according to an embodiment of the invention,
• FIGS. 2 and 3 are sections along lines II-II and III-III respectively of FIG. 1,
• FIG. 4 is a perspective view of the conical part of a diffuser according to the invention,
• FIG. 5 is a bottom view of the part of FIG. 4,
• FIG. 6 is a perspective view of the sleeve of a diffuser according to the invention,
• FIG. 7 is a bottom view of the sleeve of FIG. 6,
• FIG. 8 is a longitudinal section of a diffuser according to the invention, that is to say after assembly of the parts of FIGS. 4 and 6,
• FIG. 9 shows a nozzle head like FIG. 1 but in another form,
• FIGS. 10 and 11 are sections along the lines respectively XX and XI-XI of FIG. 9, diffusers being furthermore represented in their housings,
• FIG. 12 shows another possible nozzle head,
• FIGS. 13 is a section along line XIII-XIII of FIG. 12, diffusers being further represented in their housings as for FIGS. 10 and 11,
• FIGS. 14 and 15 correspond respectively to FIGS. 12 and 13 in another form, the section of FIG. 15 being carried out along the line XV-XV of FIG. 14.

The nozzle according to the invention shown in Figures 1 to 3 essentially comprises a partially hollow head 1 which is provided with: an opening constituting a liquid inlet 2, and several orifices forming housings 3 (Figures 2 and 3) for diffusers 4.

Each diffuser 4 consists of a sleeve 5 (Figures 6 to 8) in which is housed a conical part 6 partially hollow (Figures 4 and 5).

The sleeve 5 of the diffuser defines an interior volume 7 in the form of a cone circular provided at its top with an orifice 8, as shown in FIGS. 6 to 8, while it is provided with an external thread 9 and an internal thread 10 arranged at the base of said conical volume 7, the external thread 9 being provided to cooperate with a corresponding internal thread provided in the housings 3, as shown Figures 2 and 3.

The conical part 6 of FIGS. 4 and 5 has a corresponding apex angle to that of the conical volume 7 of the sleeve 5 and an external thread 11 at its base, conjugate of the internal thread 10 of said sleeve.

In this way we understand that the part 6 can be housed and screwed into the sleeve 5 by cooperation of the threads 10 and 11 respectively of the parts, as this is shown more particularly in FIG. 8, this operation being facilitated by the use of a tool engaged with the groove 12 of the part 6, visible in FIG. 4.

To facilitate the screwing of the sleeves 5 in the housings 3, said sleeves 5 here include holes such as 13 (Figure 7) for the use of an appropriate tool.

The part 6 (FIG. 4) also has three conical helical grooves 14a, 14b, 14c which extend, as shown in Figure 4, from the base of said part 6, each communicating with the interior thereof through an orifice 15a, 15b, 15c, up to the immediate vicinity of the apex S (FIG. 5), of said part, opposite of the spray nozzle 8 of the sleeve if we consider the assembled parts as shown in figure 8.

The top S of the part 6 thus constitutes a joint arrival of the three grooves helical.

In the example shown and as shown more particularly in the figure 5, the starting ends of the grooves 14a to 14c and therefore the orifices 15a to 15c are angularly offset two by two by an angle of substantially 120 ° C, to be regularly distributed while said grooves reach the top S of the part after a development on substantially a lap.

The angles at the top of the part 6 and of the volume 7 of the sleeve being the same (either in the embodiment of FIGS. 4 to 8 at 60 °), the grooves 14a to 14c then, by cooperating with the inner wall of the sleeve 5, form helical channels conics of liquid circulation, as shown in Figure 8.

We understand that this arrangement allows the liquid, which arrives in the head from the nozzle by the inlet 2, to reach the diffuser 4 by channels or parts suitable hollow formed in said head, as shown in the drawings.

The liquid then passes into the hollow conical part 6 and the liquid follows the three helical channels formed by the grooves 14a to 14c to exit through the orifice 8 in forming a hollow cone mist, the plurality of diffusers forming a mist full cone.

However, the inventor has discovered that part 6 may not be screwed completely in the sleeve 5 so that a space is then created between said part 6 and the inner wall of said sleeve 5 through which the helical channels can communicate with each other, as shown in Figure 8 where a space E is shown diagrammatically with broken lines.

Indeed, it has been found that this space makes it possible to vary the degree of filling the hollow cone with the liquid mist generated by the diffuser as well as the ejection distance of said mist.

It is clear that the invention also provides an embodiment in which the space E mentioned above can be created while the part 6 is fully screwed in the sleeve 5 and it suffices for this that the circular part of the part 6 located between its thread 11 and its conical part is a little shorter than the part corresponding circular of the sleeve 5 located between its thread 10 and its conical part.

It is also easy to understand that depending on the nature and shape of the fog spray, we can also act on the shape of the head and the distribution of the diffusers on it, as well as on the angle at the top of part 6 and volume 7 of the sleeve 5, as well as on the diameter of the spray orifice 8, the cross section of which will be less than the sum of the sections of the channels previously described. We could, for example, use angles at the top of 90 °, 75 °, 60 ° and 20 °.

In the embodiment shown in Figures 1 to 3 for example, the head 1 of the nozzle has substantially the shape of a pear, the diffusers being distributed on the swollen part of it.

Advantageously, according to this embodiment, one uses for the diffusers spray holes of increasing diameter and angles at summit smaller and smaller as we get closer to the area of larger diameter of the head, i.e. of the transition zone between the swollen part and the other party.

In this way, the closer we get to this transition zone, the more the liquid can be sprayed away.

In Figures 2 and 3, we can also see that the so-called central diffuser or polar, arranged in the axis of the liquid inlet 2, has an angle of about 90 ° while the other diffusers shown in Figure 2 have an angle of 75 ° and those of Figure 3 an angle of 60 °.

We understand that the central diffuser will generate the finest droplets with the greatest angle of dispersion while the diffusers of figure 2 go generate medium-sized droplets in a 75 ° dispersion cone, while that the diffusers of figure 3 will generate the largest droplets, which are going to be projected the farthest.

However, it is clear that many combinations are possible with for example 3 to 6 intermediate diffusers of 75 ° combined with or not 3 to 6 diffusers 60 ° and with or without a central or polar diffuser.

In FIGS. 9 to 15, heads of different shapes have been shown and we have kept the same references, except for the reference of the head itself numbered 1 'or 1 "or 1' '' respectively.

In FIGS. 9 to 11, the head 1 ′ shown, which relates for example to more particularly a pit nozzle, has a circular arc shape 16, the axes of the diffusers 4 being substantially coplanar along a plane passing through the axis of the liquid inlet 2, which spreads out the liquid mist according to here five main coplanar directions like the five fingers spread with one hand.

The diffusers here have an angle at the top of 60 ° but we can also use other diffusers and in particular 20 ° diffusers.

Figures 12, 13 and 14, 15 show two other possible embodiments, for example for gutters (Figures 12 and 13) and for false respectively floors or false ceilings (Figures 14 and 15).

The head 1 "of FIGS. 12 and 13 has a cylindrical part 17 coaxial with the axis of the liquid inlet 2 while the housings 3 of the diffusers 4 are provided on said cylindrical part 17, their axes being substantially coplanar according to a plane substantially perpendicular to said axis of the inlet 2 of the liquid. In this mode embodiment, the diffusers have an angle here of 20 °. Such a nozzle allows spraying lateral, for example for large areas and low heights.

The head 1 '' 'of Figures 14 and 15, on the contrary has a flat part 18 substantially perpendicular to the axis of the liquid inlet 2 and in which are arranged at an angle and open the housings 3 of the diffusers 4, said diffusers 4 having for example an angle of 20 °, so as to constitute a nozzle more especially intended for long lengths and small sections.

Claims (10)

1. Spraying nozzle for a liquid, comprising a head (1, 1', 1", 1"') provided with an inlet (2) for liquid and at least one orifice forming a housing (3) in which is disposed a diffuser (4) constituted by a sleeve (5) forming an internal volume (7) which is delimited by a circular cone the apex of which facing the outside is pierced to constitute a spraying orifice (8), and in which is housed an at least partly hollow conical part (6) of matching external shape and provided externally with at least one conical helical groove (14a-14c) which extends from the base of said conical part (6), communicating with the interior of the latter, towards its apex to form in combination with the internal wall of said sleeve a conical helical channel for circulation of the liquid, said nozzle being characterised in that the conical part (6) of the diffuser (4) comprises three conical helical grooves (14a-14c) the ends of which at the base of the part communicate directly with the interior of the latter through a separate orifice (15a-15c), said ends and hence said orifices being offset angularly two by two by an angle of substantially 120°, whereas the other ends of the grooves reach the immediate vicinity of the apex (S) of said part after development over substantially one turn to form a common inlet facing the spraying orifice (8) of the sleeve (5).
2. Nozzle according to claim 1, characterised in that the housing (3) of the nozzle designed for the diffuser (4) exhibits an internal thread designed to co-operate by screwing with a matching external thread (9) formed on the sleeve (5) of the diffuser (4).
3. Nozzle according to one of claims 1 and 2, characterised in that the conical part (6) of the diffuser (4) is provided at its base with an external thread (11) designed to co-operate by screwing with a matching internal thread (10) provided at the base of the sleeve (5) .
4. Nozzle according to one of claims 1 to 3, characterised in that the conical part (6) of the diffuser (4) is not completely introduced into the housing formed by the internal volume (7) of the sleeve (5), thus creating a space between said conical part (6) and the internal wall of the sleeve through which the helical channels can communicate with one another.
5. Nozzle according to one of claims 1 to 4, the head (1, 1', 1", 1"') of which is provided with a plurality of housings (3) for a plurality of diffusers (4), characterised in that firstly the angles at the apex of the conical parts (6) and the sleeves (5) of the diffusers (4) and secondly the diameters of the spraying orifices (8) depend on the locations of the diffusers on the head (1, 1', 1", 1''') of the nozzle as a function of the desired effect.
6. Nozzle according to one of claims 1 to 5, characterised in that the head (1) of the nozzle exhibits substantially the shape of a pear, the housing or housings (3) for the diffusers (4) being formed on its bulbous portion.
7. Nozzle according to all of claims 5 and 6, characterised in that the diffusers (4) exhibit spraying orifices (8) with diameters which increase and apex angles which decrease as their locations get closer to the zone of the greatest diameter of the head (1) of the nozzle.
8. Nozzle according to one of claims 1 to 5, characterised in that the head (1') of the nozzle exhibits substantially the shape of an arc of a circle (16), the housings (3) for the diffusers (4) being disposed in an arc of a circle, their axes being substantially coplanar in a plane passing through the axis of the inlet (2) for the liquid.
9. Nozzle according to one of claims 1 to 5, characterised in that the head (1") of the nozzle exhibits a cylindrical portion (17) coaxial with the axis of the inlet (2) for the liquid, the housings (3) for the diffusers (4) being formed on this cylindrical portion, their axes being substantially coplanar in a plane substantially perpendicular to said axis of the inlet for the liquid.
10. Nozzle according to one of claims 1 to 5, characterised in that the head (1''') of the nozzle exhibits a plane portion (18) substantially perpendicular to the axis of the inlet (2) for the liquid, the housings (3) for the diffusers (4) being formed obliquely, debouching in this plane portion (18).

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