ES2773287T3 - Full cone spray nozzle - Google Patents

Abstract

Full cone spray nozzle (1), comprising a body (2) having an inlet orifice (21) and an outlet orifice (22), and which has, on the inlet port side, a fluid inlet, which feeds a stirring chamber (3) having a substantially cylindrical peripheral wall (32), with an upstream wall (42) and a downstream wall (31), the downstream wall having an ejection orifice (30) adjacent and in direct fluid communication with the outlet orifice (22) of the nozzle, the outlet orifice (22) having a substantially frusto-conical section and the ejection orifice (30) having an essentially cylindrical section and a widened part on the side of the outlet orifice (22), the upstream wall being traversed by at least one fluid inlet channel (41) which opens in an axial direction into the stirring chamber relative to said peripheral wall (32), and being the peripheral wall traversing through at least one other fluid inlet channel (33), which empties into said agitation chamber in a tangential direction, said spray nozzle being characterized in that the upstream wall comprises at least one blind cavity (43) located at a distance of said axial inlet channel and open on a face facing the interior of the chamber, and because the cavity (43) is a peripheral groove that surrounds said channel and that presents a straight V-section.

Description

DESCRIPTION

Full cone spray nozzle

The invention relates to a spray nozzle.

A spray nozzle is externally presented as a wrap-around cover having an inlet port and an outlet port. Inside, the nozzle body is arranged to allow the dispersion of a liquid in the form of droplets and to form at the outlet a jet of droplets, or aerosol, which has a certain distribution in space. Such nozzles are used, for example, in the agricultural domain to spray phytosanitary products on crops.

Different types of nozzles are distinguished according to the particular shape of their jet: nozzles called straight jet, flat jet, cone jet, which can be a hollow cone or, also, a full cone.

The present invention is concerned with spray nozzles of the cone jet type, in particular a full cone.

The nozzle comprises a body that forms an enveloping cover and that includes one or more components and / or elements designed to disturb the jet, that is, to act on the flow of liquid, and to modify its characteristics before its expulsion by the outlet orifice, depending on the desired spray and the shape of the outlet jet required.

The nozzle body comprises a generally cylindrical shaking chamber having a central outlet port in direct communication with the outlet port of the nozzle. In order to be able to produce a conical jet, it is convenient to give the liquid flow a rotational movement upstream of the outlet orifice, so that a vortex is generated. The rotation of the flow of liquid is obtained by introducing the fluid into the interior of the agitation chamber in a direction that has a component essentially tangential with respect to a peripheral wall of said agitation chamber.

There are several types of full cone spray nozzles. Examples include axial whirl nozzles ("whirl nozzle" or "swirl nozzle") and tangential whirl nozzles.

DE 71 453 C, US 3275248 and US 4570860 describe examples of full cone spray nozzles of the axial vortex type. In these nozzles, the rotation movement of the fluid is obtained thanks to a stirring insert that closes the stirring chamber upstream of the outlet orifice and that comprises a set of substantially helical channels that allow the flow of liquid to be guided and diverted. for injection into the chamber according to the desired direction.

Whether the jet is full cone or hollow cone depends mainly on the pressure profile inside the stirring chamber.

In addition to this, an example of a tangential vortex nozzle is described in FR 2522537.

In tangential vortex nozzles, the fluid is introduced into the chamber through one or more oblique lateral channels oriented in a direction substantially tangential to the periphery of said agitation chamber and substantially perpendicular to the outlet direction of the jet. .

In this case, the fluid flows essentially around the periphery of the chamber, which provides a hollow cone jet.

To access the full cone jet, the fluid is also introduced in a substantially axial direction towards the center of the chamber, for example, through a longitudinal channel that enters the chamber through a closing piece located on the upstream side of said chamber. camera.

Therefore, there is a first part of the fluid that circulates in the periphery and a second part of the fluid that passes through the center. These two fluid parts are not subjected to the same atomizing forces. A problem with this configuration is that the dispersion of the fluid in the center of the cone is not homogeneous with the dispersion of the fluid in the periphery of the cone. More generally, large variations in fluid distribution result in a straight section of the jet.

The invention goes on to improve the spraying performances of such nozzles.

The proposed spray nozzle comprises a body that has an inlet orifice and an outlet orifice, and which has, on the side of the inlet orifice, a fluid inlet zone, which feeds a stirring chamber that has a peripheral wall substantially cylindrical, with an upstream wall and a downstream wall, the downstream wall having an adjacent ejection orifice and in direct fluid communication with the outlet orifice of the nozzle, the outlet orifice having a substantially frusto-conical section and presenting the ejection hole an essentially cylindrical section and a widened part on the side of the outlet orifice, the upstream wall being traversed by at least one fluid inlet channel that empties into the agitation chamber in an axial direction relative to said peripheral wall, and the peripheral wall being traversed by at least one other inlet channel of fluid, which empties into said stirring chamber in a tangential direction, at said spray nozzle.

The proposed spray nozzle is characterized in that the upstream wall comprises at least one blind cavity located at a distance from said axial inlet channel and open on a face facing the interior of the chamber, and that the cavity is a peripheral groove. that surrounds said channel and that presents a straight section in V.

This presence of cavities inside the agitation chamber causes additional disturbances in the fluid, which allow to obtain an improved atomization of the fluid at the core of the conical jet. In this way, a more homogeneous distribution of the fluid is obtained inside the jet.

This effect is particularly noticeable in the case of a row of nozzles forming, for example, a spray chute.

Without wishing to be bound by theory, it is believed that the fact of locating the cavity (s) at a distance from the axial inlet channel makes it possible to ensure that the fluid circulating through said channel first penetrates into the interior of the agitation chamber. The fluid that enters the cavities is therefore suitably the fluid that circulates in the chamber, and not the fluid that feeds the chamber, but has not yet entered the chamber. Furthermore, the proposed nozzle retains an extremely compact constitution.

The cavity comprises a groove.

The groove is peripheral.

The groove can be annular.

Finally, the groove has a straight V-section.

According to a particular embodiment, the upstream wall of the agitation chamber is defined, at least partially, by a closing part of said chamber. Such a configuration presents numerous advantages for the manufacture of the nozzle. The stirring chamber (which can also be called a swirl chamber) can thus be designed (in particular by machining) in the form of a chamber which is open on the upstream side. The axial channel, as well as the recess (s), can be made in this closure piece. For the final assembly of the nozzle, it is enough to mount the closure piece in the shaking chamber.

The closure piece can integrate other walls, if necessary, particularly the peripheral wall and the side channels.

Other features and advantages of the invention will become apparent upon examination of the detailed description below, and the accompanying drawings, in which:

- Figure 1 is a schematic view, in front perspective, of a full cone spray nozzle, as proposed.

- Figure 2 is a schematic view, in rear perspective, of the nozzle of Figure 1.

- Figure 3 is a schematic representation, in axial longitudinal section, of the nozzle of Figures 1 and 2.

- Figure 4 is a schematic representation, in axial longitudinal section, of the nozzle of Figures 1 and 2, taken at 90 ° in relation to the view of Figure 3.

- Figure 5 is a schematic representation, in exploded view, of the nozzle of Figures 1 and 2, in rear perspective.

- Figure 6 is a schematic representation, in an exploded view, of the nozzle of Figures 1 and 2, in front perspective.

The drawings and the description that follow essentially contain elements of a fixed character. The drawings form an integral part of the description and may, therefore, not only serve to better understand the present invention, but also contribute to its definition, if necessary.

Figures 1 to 5 show a full cone spray nozzle.

The nozzle 1 comprises a body 2 that forms an enveloping cover that protects a stirring chamber 3, with its closing piece 4, an insert 5 and a peripheral seal 6 whose objective is to ensure a seal between the insert 5 and the body 2 .

The body 2 is substantially cylindrical in shape and comprises a peripheral wall 20 that delimits an interior space intended to house the components of the nozzle 1. The body 2 may be made, for example, of plastic material.

The body 2 has an inlet orifice 21 intended to be connected to a supply of fluid to be sprayed and an outlet port 22 intended to evacuate the fluid in the form of a jet or full cone aerosol.

The body 2 has, on the side of the inlet orifice 21, a peripheral rim 23 intended to support the insert 5.

On the side of the outlet orifice 22, said outlet orifice 22 has a substantially frusto-conical section. The outlet orifice 12 also has a diameter smaller than the internal diameter of the body 2, so that it forms an internal radial stop 24.

As indicated above, the body 2 receives a shaking chamber 3.

The agitation chamber 3 is a hollow part with a substantially cylindrical shape and comprises a downstream wall 31 which has an ejection orifice 30, of substantially circular cross section, and a peripheral wall 32 that is substantially circular. According to the embodiment shown, the stirring chamber 3 does not integrate any upstream wall. The closure of the stirring chamber 3 on the upstream side is carried out by a closure part 4, which will be described in the following.

The peripheral wall 32 of the agitation chamber 3 defines a substantially cylindrical interior space. This interior space of the stirring chamber communicates with the expulsion orifice 30 through a frustoconical section front part 35. The frustoconical section front part 35 makes it possible to obtain the acceleration of the expulsion speed by concentrating the fluid towards the orifice 30.

Furthermore, the ejection hole 30 has an essentially cylindrical section and a widened part on the side of the outlet hole 22 of the nozzle 1.

On the other hand, the agitation chamber 3 comprises a front part facing the outlet orifice 22 of the nozzle 1, which has an external diameter substantially equal to the internal diameter of the body 2. The agitation chamber 3 also comprises a rear part which has an external diameter less than the internal diameter of body 2 in order to leave a circulation space between said body 2 and said agitation chamber 3. The width of the circulation space is adapted to the fluid to be sprayed and to the flow rate of said fluid through of the nozzle 1. In said rear part of the stirring chamber 3, the peripheral wall comprises two lateral openings 33 that pass through it, in this case, substantially longitudinal grooves. The lateral openings 33 are diametrically opposed and made so that they open into the stirring chamber 3 in a direction essentially tangential to the peripheral wall 32 or slightly inclined relative to said peripheral wall 32, on the inner side.

The agitation chamber 3 is arranged inside the body 2, its front part coming against the internal radial stop 24 of said body 2. The expulsion orifice 30 of the agitation chamber 3 is adjacent and in direct communication with the orifice of body outlet 22 2.

A closure part 4 is then inserted into the body 2 after the stirring chamber 3, the said closure part 4 of which closes the interior space.

The closure piece 4 has a substantially cylindrical shape and becomes a wall upstream of the stirring chamber 3.

The closure piece 4 is designed in such a way that it has a central axial channel 41 that passes through it, opening into the shaking chamber 3 on a face 42 facing the inside of said shaking chamber 3.

In addition to the channel 41 into which it opens, the face 42 has a cavity 43 located at a distance from said axial inlet channel 41.

By "remote", it is understood that there is a filled space, not in fluid communication, between the channel 41 and the cavity 43. Said channel 41 and said cavity 43 are not in fluid communication directly with each other within the closure piece 4 and, to reach the cavity 43, the fluid must previously circulate in the agitation chamber 3.

According to the embodiment shown, the cavity 43 is a peripheral annular groove that surrounds the channel 41. The cavity 43 has a straight V-section.

The closure piece 4 has a front part, facing the agitation chamber 3, which has a diameter substantially equal to that of the rear part of said agitation chamber 3.

Thus, the closure piece 4 is arranged at a distance from the wall 20 of the body 2 and, like the rear part of the agitation chamber 3, leaves a peripheral circulation space for the fluid to be sprayed.

The closure part 4 also has a rear part, facing the inlet hole 21 of the body 2 and with a reduced diameter, less than that of its front part. This rear part is intended to cooperate with the insert 5 described below, which ensures the clamping.

The insert 5 destined to secure the holding of the shaking chamber 3 and the closing piece 4 in position and to close the enveloping cover formed by the body 2 then arrives inside the body 2.

The insert 5 is positioned and fastened by screwing and has, to do this, a threaded part located close to the collar 51 and conceived to cooperate with a corresponding (not visible) threading of the body 2.

The insert 5 also constitutes a fluid inlet zone that feeds the agitation chamber 3.

The insert 5 is a hollow piece that has a generally cylindrical shape having a collar 51 intended to come to bear against the peripheral rim 23 of the body 2.

A peripheral gasket 6 arranged on the outer periphery of the insert 3, manages to ensure the sealing between the insert 5 and the body 2, close to the inlet hole 21 of said body 2.

The insert 5 extends inside the body 2 through a cylindrical extension 53 open at its two ends. The cylindrical extension 53 is intended to cooperate, by engagement, with the rear part 42 of the closure part 4.

As before, the outer diameter of the cylindrical extension 53 is less than the inner diameter of the body 2 so that a space for peripheral circulation of the fluid is left. Peripheral lateral openings 55 are located in the cylindrical extension 53, near the end destined to cooperate with the closure piece 4. These lateral openings 55 are destined to allow a part of the fluid to be sprayed to gather in the circulation space peripheral.

The circulation of the fluid through the nozzle 1 is as follows.

A supply of fluid to be sprayed is connected to the nozzle 1. The fluid enters the nozzle 1 through the orifice 21 of the body 2. More particularly, the fluid enters the nozzle through the insert 5.

The fluid passes through the insert 5 until it reaches, on the one hand, the lateral openings 55 and, on the other hand, the channel 41 of the closure piece 4.

A first part of the fluid to be sprayed passes through the openings 55 and reaches the peripheral circulation space that extends to the stirring chamber 3 after the closure piece 4 has passed along.

When the first part of the fluid reaches the agitation chamber 3, said part of the fluid passes through the tangential openings 33 and penetrates inside said agitation chamber 3 at the desired angle.

The first part of the fluid is thus animated by a turbulent movement.

A second part of the fluid to be sprayed axially passes through the insert to join the closure piece 4 and its channel 41.

The second part of the fluid passes through said channel 41 to reach the stirring piece 3, into which said channel 41 opens.

The second part of the fluid thus joins the first part of said fluid substantially in the center of the vortex. In addition to the vortex movement with which the fluid is animated inside the chamber, said fluid also comes into contact with the face 42 and its cavity 43. The circulation of the fluid in the cavity 43 creates additional disturbances at the outlet of said fluid, which favors its atomization.

The first part of the fluid is then expelled through the hole 30 of the stirring chamber 3, then through the outlet hole 22 of the body 2 to exit the nozzle 1 in a full cone configuration.

Although the invention has been described with particular exemplary embodiments, it is in no way limited thereto and comprises all technical equivalents of the means described, as well as their combinations, which are covered by the scope of the appended claims.

As already described, the cavity is a peripheral annular groove or groove.

Alternatively, the cavity can be a hole.

Furthermore, the upstream wall of the agitation chamber can have several cavities. The cavities can be distributed peripherally or partially peripherally.

The cavities can also be concentrically arranged.

Claims (5)

1. Full cone spray nozzle (1), comprising a body (2) having an inlet hole (21) and an outlet hole (22), and having, on the side of the inlet hole, a fluid inlet zone, which feeds a stirring chamber (3) having a substantially cylindrical peripheral wall (32), with an upstream wall (42) and a downstream wall (31), the downstream wall having an orifice outlet (30) adjacent and in direct fluid communication with the outlet orifice (22) of the nozzle, the outlet orifice (22) having a substantially frustoconical section and the expulsion orifice (30) having an essentially cylindrical section and a part widened on the side of the outlet orifice (22), the upstream wall being traversed by at least one fluid inlet channel (41) which opens in an axial direction into the stirring chamber in relation to said peripheral wall (32 ), and being the peripheral wall traverses is formed by at least one other fluid inlet channel (33), which empties into said agitation chamber in a tangential direction, said spray nozzle being characterized in that the upstream wall comprises at least one blind cavity (43) located at a distance of said axial inlet channel and open on a face facing the interior of the chamber, and because the cavity (43) is a peripheral groove that surrounds said channel and has a straight V-section. Spray nozzle (1) according to claim 1, characterized in that the groove is peripheral. Spray nozzle (1) according to claim 2, characterized in that the groove is annular. Spray nozzle (1) according to any one of claims 2 and 3, characterized in that the groove has a substantially V-shaped profile in a straight section. Spray nozzle (1) according to any one of Claims 1 to 4, characterized in that the upstream wall (42) of the stirring chamber (3) is defined, at least partially, by a closing piece (4 ) of said camera.