WO2009088309A2

WO2009088309A2 - Spraying apparatus

Info

Publication number: WO2009088309A2
Application number: PCT/NZ2008/000342
Authority: WO
Inventors: Christopher Graham Venn
Original assignee: Christopher Graham Venn
Priority date: 2008-01-07
Filing date: 2008-12-19
Publication date: 2009-07-16
Also published as: NZ564937A; WO2009088309A3

Abstract

A spraying apparatus for distributing liquid, which includes an elongate spray boom, an elongated shroud configured to fit the spray boom, a mounting chassis for the spraying apparatus, the mounting chassis configured with a ground engaging mechanism, characterised in that the spray boom is configured to be mounted to the front of a vehicle such that the bottom of the shroud extends to be in close proximity to the ground, and the ground engaging mechanism is mounted to the mounting chassis such that the spray boom is forward of the ground engaging mechanism.

Description

SPRAYING APPARATUS

TECHNICAL FIELD

The present invention relates to a spraying apparatus. The present invention has particular application to the spraying of chemicals such as herbicides or pesticides.

BACKGROUND ART

It is well known to use vehicles as a mount for a chemical spraying apparatus. The advantage of using a vehicle for this purpose is that it permits large amounts of chemicals to be carried by the vehicle in on-board tanks, and large areas can be covered relatively quickly by the vehicle.

An example of such a vehicle is the subject of New Zealand Patent No. 195145.

This patent describes the use of a controlled droplet spraying unit mounted to a boom which is in turn attached to the rear of a motorbike. This is an adequate method of spraying chemicals such as pesticides or herbicides. However, this spraying apparatus presents a number of problems in its use.

Mounting the boom to the rear of the vehicle makes the apparatus awkward for an operator to use with any accuracy. The vehicle operator must shift his or her attention from the road or ground being traversed by the vehicle to the spraying apparatus to ensure that the dispensed chemicals are being applied to the desired areas.

This can be dangerous in certain environments, particularly when using the vehicle over uneven ground or when there are a number of navigational hazards.

Another problem encountered when using the apparatus disclosed in New Zealand Patent No. 195145 is the dispersal effect on the chemicals being sprayed when the apparatus is used in windy or breezy conditions.

Even a very light wind can cause dispersal of the sprayed droplets of chemicals, sometimes into or onto areas where it is not desired. It is particularly problematic where very controlled and precise spraying is required, for example when spraying weeds adjacent to a children's playground.

Another consideration is the nature of the chemicals being sprayed. Most pesticides and herbicides are toxic to humans as well as domesticated animals.

It is well known of the detrimental effects on a person's health following both short and long term exposure to toxic chemicals. For example, the defoliant used to eradicate plants in Vietnam during the late 1960's and early 1970's has resulted in well documented cancer related illnesses in Vietnam War veterans.

Thus it is preferable to minimise exposure to chemicals such as pesticides and herbicides. This can be difficult to achieve if spraying is done in areas such as parks, where people may be walking dogs or exercising. It should also be borne in mind that the operator of the spraying apparatus in particular can be exposed to the toxic chemicals being dispensed.

Therefore, it is a common practice by operators of spraying apparatus to not spray in conditions where the wind is above a certain speed, to ensure the safety of the operator and nearby persons. However, this can impact economically on the operator, through lost work time and running costs.

To reduce any overspray of chemicals, some operators of spraying apparatus may use a shroud or cover in conjunction with the spraying apparatus. This helps to ensure that the chemicals are applied where desired. One such shroud is disclosed in New Zealand Patent No. 251946.

This patent discloses a circular shroud for a spraying apparatus mounted to a quad bike, and is designed for use in and around vegetation such as grape vines.

The shroud is deformable, allowing the material of the shroud to deform to any obstacles or obstructions, which may be passed over by the shroud in use. In addition, the shroud is configured to rotate when it contacts an obstruction, such as a vine stake.

However, this shroud is mounted to the side of the vehicle to which a spraying apparatus is secured. This makes it awkward for the operator to place the sprayed chemicals where desired. .

When using the apparatus disclosed in New Zealand Patent No. 251946, the operator must also be conscious of the width of the vehicle with the apparatus attached. Inexperienced operators may have difficulty allowing sufficient space for navigating obstacles on the same side of the vehicle as the spraying apparatus.

Although the deformable nature of the shroud means that there is little if any damage to the shroud in the event of a misjudgement, the operator may need to reverse the vehicle and re-orientate the vehicle to ensure complete coverage of the area being sprayed.

This is also the case with another sprayer in the prior art, the Grasshopper Frontmount™ shielded sprayer

(www.grasshoppermower.com/fm_imp_sprayer.php). This system mounts a shielded sprayer to a mower via a frame which under which the shielded sprayer is fixed.

The frame is provided with wheels at its leading edge for support. However, these prevents the operator moving directly forward and spraying edges and the like.

The operator must swing the vehicle parallel to the area being sprayed and run the end portion of the sprayer along the edge to be sprayed. This is not always practical when space is limited, and takes longer to achieve.

The tanks of the Grasshopper sprayer which contain the liquid being sprayed also make it difficult for the sprayer to remain in the operator's field of vision. This is problematic when precise spraying is required.

All references, including any patents or patent applications cited in this specification are hereby incorporated by reference. No admission is made that any reference constitutes prior art. The discussion of the references states what their authors assert, and the applicants reserve the right to challenge the accuracy and pertinency of the cited documents. It will be clearly understood that, although a number of prior art publications are referred to herein, this reference does not constitute an admission that any of these documents form part of the common general knowledge in the art, in New Zealand or in any other country.

It is acknowledged that the term 'comprise' may, under varying jurisdictions, be attributed with either an exclusive or an inclusive meaning. For the purpose of this specification, and unless otherwise noted, the term 'comprise' shall have an inclusive meaning - i.e. that it will be taken to mean an inclusion of not only the listed components it directly references, but also other non-specified components or elements. This rationale will also be used when the term 'comprised' or 'comprising' is used in relation to one or more steps in a method or process.

It is an object of the present invention to address the foregoing problems or at least to provide the public with a useful choice.

Further aspects and advantages of the present invention will become apparent from the ensuing description which is given by way of example only.

DISCLOSURE OF INVENTION

According to one aspect of the present invention there is provided a spraying apparatus for distributing liquid, which includes;

an elongate spray boom, and;

an elongated shroud configured to fit the spray boom, and;

a mounting chassis for the spraying apparatus, the mounting chassis configured with a ground engaging mechanism,

characterised in that the spray boom is configured to be mounted to the front of a vehicle such that the bottom of the shroud extends to be in close proximity to the ground, and the ground engagement mechanism is mounted to the mounting chassis such that the spray boom is forward of the ground engagement mechanism.

The spraying apparatus may be any apparatus configured to dispense liquid as a fine mist or droplets of liquid. For example, the apparatus may be a nozzle supplied with liquid from a tank via hoses.

A spray boom should be understood to mean a relatively long conduit, configured with apertures along its length or bearing a spraying mechanism such as a nozzle or series of nozzles. For example, the spray boom may be a rubber hose, but preferably the spray boom is a length of metal or plastics material tubing. Persons skilled in the art will appreciate that other materials may be employed for the construction of the spray boom.

Preferably, the boom is elongate with a length far greater than its width. In preferred embodiments, the spray boom is of a length which is double the width of the vehicle to which it is mounted. This is a suitable length as it ensures the operator will not need to run overlapping lengths when spraying, while ensuring a sufficient area is being covered. Persons skilled in the art will appreciate that the boom may be of a shorter length if required. However, it is preferable for the boom length to be at least the width of the vehicle. If the length of the spray boom is less than this, then the vehicle may need to run overlapping lengths in order to apply spray to the area desired.

Preferably, the spray boom is mounted at its centre. However, in some embodiments of the present invention, the spray boom may be mounted such that the spray boom favours one side of the vehicle to which it is mounted.

Preferably along the length of the spray boom is a series of outlets for the liquid being dispensed. The outlets may be nozzles or electronically controlled valves.

Preferably the outlets are t-jets. T-jets are spray nozzles which emit a spray of liquid droplets in a flat fan spray, which is an efficient spray pattern to ensure sufficient application of the liquid to the surface being treated. The rate of application depends on the size of the t-jet as well as the speed at which the t-jet passes over the surface being treated.

Preferably, the spray boom uses a series of t-jets, with a spray angle of 120° to ensure that each fan of sprayed droplets overlaps its neighbouring fan of sprayed liquid, thus ensuring complete coverage of the ground being sprayed.

The liquid may be any liquid which is desired to be applied to a substrate or surface. For example, the liquid may be water or fertilizers applied to grass or other plants. Preferably, the liquid is a chemical, such as a herbicide or pesticide, and shall be referred to as such throughout the remainder of this specification.

However, persons skilled in the art will appreciate that the present invention is not limited to herbicides or pesticides. For example, the present invention may used to spray paints or dyes onto the ground, to demarcate a specific area, or a surface application or coating, such as settable plastics or wax. The vehicle may be any vehicle which has the size and manoeuvrability to traverse the area being sprayed. For example, the vehicle may be an automobile, tractor or quad bike. Preferably, the vehicle is a ride-on mower.

The ride-on mower may be any brand of mower such as a John Deere® mower, but preferably is a Walker® mower, manufactured by the Walker Manufacturing Company.

A Walker® mower is preferred as the mowing mechanism is separate to the vehicle. The mowing mechanism is connected to the front of the mower via an articulated joint. Essentially, the mowing mechanism is pushed by the mower. Walker® is a type of mower which is in common use by many lawn contractors.

Persons skilled in the art should appreciate, however, that the present invention may be used with any brand of mower with suitable adaptations made as required.

Using a mower as a vehicle for mounting a spraying apparatus is advantageous as it makes the mower itself more versatile. It can be used as a mower with its cutting mechanism attached, or as a sprayer with the present invention attached.

Mounting the spraying apparatus to the front of the vehicle, forward of the operator, makes it easier for the operator to control the placement of the chemicals being dispensed. Unlike the prior art, the spraying apparatus is a forward extension of the vehicle. The operator of the vehicle is better able to judge distances and spaces than with an apparatus mounted to the side or rear of the vehicle.

Preferably, the spray boom is mounted to the vehicle via the hitch provided by Walker® to mount the Walker® mowing apparatus.

This is the preferred arrangement of the present invention, as it requires no adjustment to the Walker® mower to use the spray boom. Therefore, off the shelf Walker® mowers can readily be used with no modifications required to install and use the spraying apparatus.

No bolts are required to connect the spray boom to the mower. A hitch is a quick release coupling which allows the mowing mechanism and the spraying apparatus to be quickly interchanged as required without resorting to tools. However, persons skilled in the art will appreciate that other methods of securing the boom to the mower may be used as appropriate.

Preferably, the boom is provided with a mounting chassis. The mounting chassis may be any frame which is configured to mount the boom. Preferably, the mounting chassis is manufactured from a steel alloy for durability and strength, although persons skilled in the art will appreciate other materials may be used.

Preferably, the boom is mounted to the forward portion of the chassis, such that the boom is the most forward or front portion of the combined spraying apparatus and vehicle.

The mounting chassis is provided with a ground engagement mechanism.

The ground engagement mechanism may be any means by which the mounting chassis is supported over the ground. For example, the ground engagement mechanism may be skids or blades, but preferably is a wheel or set of wheels.

In preferred embodiments of the present invention, the mounting chassis may be provided with at least two wheels. This helps bear the weight of the boom and chassis, and reduces the strain on the hitch of the_. Walker® mower. Persons skilled in the art will appreciate that when using the present invention over uneven ground, at least two wheels is preferred for maximum stability.

The wheels of the mounting chassis are located such that no portion of the wheel extends forward of the spray boom. This allows the user of the apparatus to spray right up to and around defined areas which would be hindered or inaccessible if the wheels were mounted forward of the spray boom.

Preferably, the boom is mounted to the mounting chassis via quick release or snap lock coupling means. This ensures that the boom can be quickly removed or mounted as desired, without resorting to tools.

Preferably, the mounting chassis is configured to retain or hold the boom and its associated paraphernalia. Such paraphernalia may include a tank to hold the chemicals being sprayed, electronic hardware, hoses, supplementary spraying apparatus and the like.

Preferably, the tank may be moulded from plastics material, such as polyvinyl chloride (PVC), using conventional rotational moulding or injection moulding techniques, but preferably is constructed from metal, such as aluminium, for maximum strength and longevity. The tank may be provided with internal baffles minimise and control the movement of liquid within the tanks when the vehicle is moving.

Preferably, the tank is provided with drainage ports, to permit the passage of liquid from the tank when emptying or cleaning the tank.

In some embodiments of the present invention, the tank may be provided with a spillage tray, to capture any inadvertent spills as the tank is filled or emptied.

Preferably, the tank is configured with rub or nudge bars running along its lower surface. This provides a degree of protection for the tank from curbs and rough ground which may be traversed by the vehicle and otherwise damage the lower surfaces of the tank.

Preferably, the tank is situated low down on or within the chassis. This helps place the tank out of the direct line of sight of the user of the apparatus, so that there is an unhindered field of vision. This allows the operator of the apparatus to accurately place the liquid being sprayed, even when the front of the sprayer is abutting an obstacle or area where spray is not desired. Placing the tank low down also lowers the centre of gravity, which is an important safety consideration if the apparatus is used on sloping terrain.

Preferably, the mounting chassis is provided with a pressurizing means for the liquid, such as a pump. This ensures that the liquid is delivered to the spray boom at a sufficient pressure to ensure the liquid is dispersed as fine droplets.

Preferably, the pump is a 12 volt electric pump, powered via the onboard 12 volt battery of the mower. A 12 volt pump is sufficient to generate up to 60 pounds square inch, which is sufficient to ensure the liquid is dispersed as fine droplets.

Preferably, the mounting chassis is configured with an on-board central processing unit (CPU), such as that manufactured by Farm Scan® or C-Dax®. However, persons skilled in the art will appreciate that any suitable off-the-shelf CPU may be used.

The CPU may monitor a number of parameters when the spray boom is being operated. For example, the CPU may monitor the output of the spray boom and the speed of the vehicle to determine the rate of application and coverage of the sprayed chemicals. If outside of set parameters, the CPU may increase or reduce the pressure generated by the pump to ensure the appropriate amount of chemicals is being applied to the area being sprayed.

Alternatively, the CPU may send a signal to an instrumentation display to indicate to the operator that they should speed up or slow down the speed of the vehicle to ensure the appropriate amount of chemicals is being applied to the ground being sprayed.

In some embodiments of the present invention, the mounting apparatus may carry a marking agent. Sometimes, it is desirable to introduce a marking agent to the area that has been sprayed to make it easier for the operator to see what areas have had chemicals applied.

A common marking agent used for this purpose is off-the-shelf foaming agent. The foaming agent may be introduced directly to the ground surface via hoses and nozzles to the boom, or have a dedicated outlet, preferably at the extreme ends of the spray boom, so that the operator can see the extent of the sprayed area.

Preferably, the mounting chassis is configured with a hitch, to allow the mounting chassis to be attached to a vehicle.

Preferably, the hitch is a quick release coupling which allows the spray boom and chassis to be quickly mounted to the Walker© mower when required, without resorting to tools. However, persons skilled in the art will appreciate that other methods of securing the mounting chassis to the mower may be used as appropriate.

Preferably, the mounting chassis is configured to hold the boom such that the boom is moveable in a vertical orientation. This allows the boom to be raised and lowered as required. This ensures that the boom remains in close proximity to the ground, with minimal ground clearance.

The shroud may be any covering or housing which is placed proximate to the spray boom, covering the upper and side surfaces of the outlets.

The shroud may be a cover, blanket or tarpaulin made from canvas or plastic sheets.

Preferably the shroud is a rigid cover complementary to the spray boom.

Preferably the shroud is moulded from plastics material, such as PVC, using conventional rotational or injection moulding techniques. However, persons skilled in the art will appreciate that the shroud may be constructed from any suitable material, such as carbon fibre or aluminium. This provides some rigidity to the shroud, and protection to its underlying spray boom.

Preferably, along the lower edges of the shroud there is a skirt of deformable material. This material may be a plastic or canvas sheet but preferably are bristles. Preferably, the bristles are made from plastics material. This allows the lower edges of the shroud to deform if it encounters an obstacle such as a tree stump or bollard, or runs over uneven ground, but at the same time containing the spray to the ground area covered by the shroud.

When placed in close proximity to the ground being sprayed, such that there is little or no ground clearance, the shroud defines an enclosed space. This constrains the sprayed liquid, ensuring that the dispersal of the liquid is limited to the ground area defined by the perimeters of the shroud.

Preferably, the t-jets of the spray boom pass through the shroud, such that the outlet of the t-jet is under the shroud. However, persons skilled in the art will appreciate that in some embodiments of the present invention, the shroud may enclose the entire spray boom rather than the t-jets depending from the spray boom.

In use, the shroud defines a catchment area for the chemicals being dispensed. Any overspray from the t-jets of the spray boom is caught by the shroud, and through the action of gravity, the chemical runs down the inside of the shroud to its lower edges where it drips on to the ground being, treated.

This provides for accurate placement of the desired chemicals to the target area.

The shroud also acts as a barrier to external influences, particularly wind. This stops wind dispersal of the spray droplets being dispensed. This significantly reduces the exposure to chemicals to the operator, and persons nearby the spraying area.

In some embodiments of the present invention, the chassis may be provided with a retractable hose reel connected to a handheld spraying apparatus such as a spray gun for use when the operator of the spraying apparatus has dismounted the vehicle. The hose reel may be plumbed to the main tank, or may have a separate tank for holding liquid to be dispensed via the spray gun. This may be used for particularly detailed spraying as necessary, or for when liquids other than the liquid being dispensed from the main tank. For example, the spray gun may be used to spray herbicide while the main spraying apparatus is used to distribute pesticides.

In other embodiments of the present invention, the mounting chassis may be configured with an articulated arm with a spray boom which is narrower than the width of vehicle mounted at its end. The articulated arm may be mounted to the front of the chassis to ensure that it is visible to the operator of the spraying apparatus. This is another option for detailed spraying of areas where the use of the larger spraying apparatus is inappropriate. The smaller spray boom may be provided with a wheel to allow it to traverse and follow terrain independently of the vehicle.

It will be appreciated that the present invention offers a number of advantages over the prior art.

• Controlled and accurate placement of chemicals regardless of environmental factors, such as wind.

• Greater protection to the operator, and nearby persons and animals from chemicals being sprayed.

• Reduces the placement of chemicals to the targeted area. • Relatively inexpensive to manufacture.

• Easily fitted to existing vehicles such as Walker® ride-on mowers.

• Can be easily adapted to be used with a number of different mowers with mounting hitches to the front of the vehicle.

• Provides greater versatility for the mower to which the spraying apparatus is attached.

• Allows high precision spraying in relatively small areas.

BRIEF DESCRIPTION OF DRAWINGS

Further aspects of the present invention will become apparent from the following description which is given by way of example only and with reference to the accompanying drawings in which:

Figure 1 A front view of the present invention; and

Figure 2 a cross-section of the present invention, and

Figure 3 a plan view of the present invention, and

Figure 4 a side view of the present invention.

BEST MODES FOR CARRYING OUT THE INVENTION

In Figure 1 , the present invention (generally indicated by arrow 1) is mounted to a Walker® ride-on mower (2).

The shroud (3), consists of two components, the housing (4), and the skirt (5). The housing (4) is constructed from plastics material such as PVC. Along the housing (4) of the shroud (3), the spray boom is fitted (6). Depending downwards from the spray boom (6) at selected points along its length, t-jets (7) are fitted, passing through the housing (4) of the shroud (3).

The spray boom (6) is provided with a hose (8) at one end (9) to carry the liquid (not shown) from the tank (not shown) to the t-jets.

The skirt (5) of the shroud (3) is constructed from plastic bristles held in place by a retaining strip (10) running the circumference of the skirt (5).

The shroud (3) is illustrated in cross-section in Figure 2.

The plastic bristles of the skirt (5) are held in position by the retaining strip (10). The retaining strip (10) in turn is fixed to the housing (4) of the shroud (3).

The t-jet (7) descends from the spray boom (6) running along the upper surface of the housing (4). The lower portion (11) of the t-jet (7) terminates beneath the housing (4), in the enclosed space (12) defined by the shroud (3).

Liquid (not shown) is emitted as a fine spray from the lower portion (11 ) of the t-jet (7) into the space (12) defined by the shroud (3), and falls to the ground (13) covered by the shroud (3).

The housing (4) and the skirt (5) of the shroud (3) prevents the spray from drifting and contacting the ground area outside (14) of the defined area (13) of the shroud (3).

In Figure 3, the spray boom (6) and its shroud (3) are mounted to a chassis (15).

The chassis (15) carries a number of accessories associated with the spray boom (6), such as the liquid tank (16), which can be constructed from metal or moulded from plastic. This carries the liquid (not shown) which is to be distributed to the spray boom (6) via the hose (8). The tank (16) is situated low down in the chassis (15) to keep the centre of gravity of the chassis (15) as low as possible. The upper surfaces of the tank (16) may be textured (17) to provide grip. In use, the operator's feet rest on this surface. For the operator's comfort, the upper surface of the tank (17) is angled to provide a more natural resting position for the operator's feet (not shown) than a flat surface.

To ensure that the liquid being applied is delivered to the t-jets (7) at a sufficient pressure, the liquid passes through a 12 volt electric pump (18), which can generate up to 60 pounds square inch.

The chassis (15) is also configured with mounting hitches (19, 20) to allow the chassis to be mounted to a Walker® mower (not shown).

The spray boom (6) is mounted to the chassis via an articulated mounting frame (21). This is hinged to permit raising and lowering of the spray boom (6) if required to avoid obstacles.

The placement of the wheels (22) behind the boom (3) ensures that the wheels do not inhibit placement of the spray boom (3) and thus spray coverage when in use.

The chassis (15) is illustrated in a side view in Figure 4, mounted to a Walker® mower (2).

The chassis (15), which is manufactured from an alloy steel or similar material for durability and robustness, is provided with wheels (22) to help bear the weight of the spray boom (6) and its shroud (3), thus reducing the strain on the hitch (20) and the Walker® towing hitch (23).

The mounting frame (21 ) for the spray boom (6) and shroud (3) is in a raised state. The frame (21 ) can be moved in the plane of travel indicated by arrow 24.

The spray boom (6) can also be articulated at the front hitch (25) in the direction indicated by arrow 26, to ensure the boom (6) and its shroud (3) is orientated vertically regardless of the orientation of the mounting frame (21 ).

As well as the tank (16) and electric pump (18 - hoses from pump to spray boom not shown for sake of clarity), the chassis (15) also carries a cylinder (27) for marking foam. This cylinder (27) has its own hoses (not shown for sake of clarity) and nozzle (not shown for sake of clarity) running to the end of the spray boom (6).

The tank (16) has been provided with a rub bar (28) to help protect the tank (16) when the Walker® mower (2) is moving over uneven ground. The angled upper surface (29) of the tank (16) provides a footrest for the operator.

It should be appreciated that the mounting of the tank (16) within the chassis (15) in the manner illustrated helps lower the centre of gravity of the present invention (1 ) and thus provides greater stability and safety for the operator.

Aspects of the present invention have been described by way of example only and it should be appreciated that modifications and additions may be made thereto without departing from the scope thereof as defined in the appended claims.

Claims

WHAT I/WE CLAIM IS:

1. A spraying apparatus for distributing liquid, which includes;

an elongate spray boom, and;

an elongated shroud configured to fit the spray boom, and;

characterised in that the spray boom is configured to be mounted to the front of a vehicle such that the bottom of the shroud extends to be in close proximity to the ground, and

the ground engaging mechanism is mounted to the mounting chassis such that the spray boom is forward of the ground engaging mechanism.

2. A spraying apparatus as claimed in claim 1 wherein the ground engaging mechanism is provided with at least two wheels.

3. A spraying apparatus as claimed in either claim 1 or claim 2 wherein the mounting chassis is configured to be attached to a vehicle.

4. A spraying apparatus as claimed in claim 3 wherein the vehicle is a ride-on mower.

5. A spraying apparatus as claimed in either claim 3 or claim 4 wherein the mounting chassis is configured with a hitch.

6. A spraying apparatus as claimed in any of the preceding claims wherein the mounting chassis includes a tank for holding liquid to be distributed.

7. A spraying apparatus as claimed in claim 6 wherein the tank is mounted to lower the overall centre of gravity of the apparatus.

8. A spraying apparatus as claimed in either claim 6 or claim 7 wherein the tank is configured with rub or nudge bars running along its lower surface.

9. A spraying apparatus as claimed in any of the preceding claims wherein the mounting chassis is provided with a pressurising means for the liquid to be distributed.

10. A spraying apparatus as claimed in claim 9 wherein the pressurising means is a pump.

11. A spraying apparatus as claimed in claim 10 wherein the pump is electrically connected to the vehicle.

12. A spraying apparatus as claimed in any of the preceding claims wherein the mounting chassis includes a marking agent dispenser.

13. A spraying apparatus as claimed in claim 12 wherein a dedicated outlet for the marking agent is situated at the extreme edges of the spraying mechanism.

14. A spraying apparatus as claimed in any of the preceding claims wherein the mounting chassis is provided with a central processing unit (CPU) monitoring and / or controlling the rate of spraying.

15. A spraying apparatus as claimed in any of the preceding claims wherein the spray boom includes outlets along its length.

16. A spraying apparatus as claimed in claim 15 wherein the spray boom includes T- jet spray nozzles along its length.

17. A spraying apparatus as claimed in either claim 15 or claim 16 wherein the shroud is a rigid cover complimentary to the spray boom.

18. A spraying apparatus as claimed in claim 17 wherein the shroud includes a skirt of deformable material around its lower edges.

19. A spraying apparatus as claimed in claim 18 wherein the skirt of deformable material are bristles.

20. A method of distributing liquid using the spraying apparatus as claimed in any of the preceding claims.

21. A spraying apparatus for distributing liquid substantially as herein described with reference to and as illustrated by the accompanying drawings.

22. A method of distributing liquid using a spraying apparatus substantially as herein described with reference to and as illustrated by the accompanying drawings.