GB2452580A

GB2452580A - Mix and spray nozzle arrangement

Info

Publication number: GB2452580A
Application number: GB0802794A
Authority: GB
Inventors: Dave Edward Bickers
Original assignee: Individual
Current assignee: Individual
Priority date: 2007-09-07
Filing date: 2008-02-15
Publication date: 2009-03-11
Anticipated expiration: 2028-02-15
Also published as: GB0717377D0; GB0802794D0; GB2452580B; GB2452532A

Abstract

A spray nozzle assembly, possibly for spraying agrochemicals, includes a nozzle body 14, possibly to be mounted on a spray boom, and a nozzle 10 which fits in the body and is removable therefrom. The body 14 has an external shoulder 20 intermediate the ends of the nozzle 10 so that part of the nozzle 10 can be housed within the body 24 with the result that the nozzle is less protuberant and less likely to suffer damage. Nozzle 10 is held in position by cap 16 via bayonet or screw thread fixtures. Shoulder 20 is seated on a recessed surface 22 of body 14 so as to act as a pressure tight seal. Air is drawn up through passages 34, mixed with a liquid in chamber 32, and then expelled as an atomized spray 40, at spray tip38, after traveling along elongated channel 36. Air inlets/passages 34 may be on the same face as nozzle outlet/tip 38. Seal ring / gasket 24 may be positioned between shoulder 20 and recessed surface 22.

Description

Spraying Apparatus This invention relates to spraying apparatus, and in particular to a spraying nozzle especially adapted to spray agrochemicals.

A spraying nozzle for spraying agrochemicals Is described in UK patent application GB 2256817.

Spraying of agrochemicals takes place from a spray boom mounted on a tractor or similar agricultural vehicle. The booms extend a considerable distance either side of the vehicle, and have an array of nozzle assemblies arranged along the length of the boom.

Each nozzle assembly comprises a nozzle body and nozzles which are removable from the nozzle body for cleaning. The nozzles project from the body and can be vulnerable to being damaged, for example if any part of the boom catches on a relatively rigid obstruction, or extends into a hedge when the

vehicle is making a turn at en edge of a field.

The present invention seeks to reduce the extent to which the nozzles project, in order to make the nozzles less exposed to such damage.

According to the invention, there is provided a spray nozzle comprising an inlet for liquid, an inlet for air, both inlets leading to a chamber in which the air and the liquid are mixed, an elongate passage along which the mixed air and liquid can travel, and an outlet, wherein the nozzle is provided with an external shoulder arranged on the exterior of the nozzle surrounding the elongate passage.

in use, the nozzle is mounted in a nozzle body, and the external shoulder locates on a landing surface in the nozzle body. By locating the shoulder away from the liquid entry port, the nozzle can fit partly within the nozzle body, with the result that the nozzle projects a minimal distance from the nozzle body. The nozzle body itself requires no modification to achieve this desired result.

The air inlet may be on the same face of the nozzle as the outlet from the nozzle.

Preferably the nozzle can be separated into two parts, for cleaning purposes, and the separation plane may coincide with the external shoulder. The separation plane preferably includes locating bosses on one part which locate in corresponding recesses on the other part. The bosses may surround the air inlet passages.

The invention also provides an air induction nozzle in which liquid and air are mixed to produce a spray of liquid droplets mixed with air, wherein liquid and air are Introduced into the nozzle in such a way that air is drawn in to the nozzle by the liquid through a venturi effect, the nozzle having a nozzle head from which the spray is emitted and a nozzle body in which the mixing takes place, the nozzle head being shorter than the nozzle body, and wherein air enters the nozzle through air inlets in the nozzle head, the nozzle head and body being separable from one another.

The invention will now be further described, by way of example, with reference to the accompanying drawings, in which: Figure 1 is a sectional view, showing a nozzle in accordance with the invention in place in a nozzle body; -3.-.

Figure 2 shows the nozzle of Figure 1 separated into its two parts; Figure 3 is a schematic perspective view showing the configuration of the surface X1 from Figure 2; Figure 4 is a top view of the assembled nozzle; and Figure 5 is a bottom view of the assembled nozzle.

Figure 1 shows a nozzle 10 fitted into a bore 12 in a nozzle body 14. The nozzle is held in place by a nozzle cap 16 whIch is locked onto the outside of the body 14 by means not shown in the drawing but which might be a bayonet fitting or a screw thread fitting.

The external diameter of the nozzle is such that it will fit inside the body 14, and the nozzle has an external shoulder 20 which seats on a recessed surface 22 of the body. A seal ring or gasket 24 is fitted between the shoulder 20 and the surface 22 and when the cap 16 is secured, a pressure tight seal is made between the shoulder 20 and the surface 22.

In use, liquid under pressure is fed from a central reservoir, along spray booms into nozzle bodies 14. Typically there may be as many as forty eight nozzle bodies arranged along the length of a spray boom. The liquid arrives in the space 26 and can only escape through the nozzle 10. The nozzle has a liquid inlet 30 which lead into a mixing chamber 32. At the same time, air is drawn into the mixing chamber along air passages 34. The air is drawn in through a venturi effect as the high pressure liquid enters the space. Various configurations are known to ensure that the desired degree of mixing takes place and that the desired volume of air is drawn in, but those configurations form no part of the present invention.

The liquid/air mixture then travels along a passage 36 to a spray tip 38 from which it emerges as an atomised spray 40.

Nozzles of this type often require cleaning as deposits may build up inside. The nozzle described here can be separated into two parts, allowing cleaning, by making the nozzle in two (or more) parts which can be separated on an interface line indicated by dotted lines in Figure 1.

Figure 2 shows the two parts separated. The lower part 40 includes the spray tip 38. On the interface end of the part 40, the passages 34, 36 end in circular bosses 42 which fit into corresponding recess 44 on the upper part. To reassemble the nozzle, the bosses have to fit in the recesses, thus making sure that the parts are correctly aligned. As will be seen from Figure 2, the separation plane divides the shoulder 20 in two (see 20a, 20b), and when the cap 16 is put in place, securing the cap will act to press the two parts of the nozzle against one another to hold the nozzle together.

Claims

Claims 1. A spray nozzle comprising an inlet for liquid, an inlet for air, both inlets leading to a chamber in which the air and the liquid are to be mixed, an elongate passage leading from the mixing chamber and along which the mixed air and liquid can travel, and an outlet, wherein the nozzle is provided with an external shoulder arranged on that part of the exterior of the nozzle surrounding the elongate passage.
2. A nozzle as claimed in Claim 1, wherein the shoulder is an annular shoulder.
3. A nozzle as claimed in Claim I or Claim 2, wherein the air inlet is on the same face of the nozzle as the outlet from the nozzle.
4. A nozzle as claimed in Claim 3, wherein the air inlet comprises two air inlet passages.
5. A nozzle as claimed in any preceding claim, wherein the nozzle can be separated into two parts, for cleaning purposes.
6. A nozzle as claimed in Claim 5, wherein the separation plane coincides with the external shoulder.
7. A nozzle as claimed in Claim 5 or Claim 6, wherein the separation plane includes locating bosses on one part which locate in corresponding recesses on the other part.
8. A nozzle as claimed in Claim 7, wherein the bosses surround the air inlet passages.
9. An air induction nozzle in which liquid and air are mixed to produce a spray of liquid droplets mixed with air, wherein liquid and air are introduced into the nozzle in such a way that air is drawn in to the nozzle by the liquid through a venturi effect, the nozzle having a nozzle head from which the spray is emitted and a nozzle body in which the mixing takes place, the nozzle head being shorter than the nozzle body, and wherein air enters the nozzle through air inlets in the nozzle head, the nozzle head and body being separable from one another.
10. A nozzle substantially as herein described with reference to the accompanying drawings. j I