NZ618624B2 - Wetting apparatus and method of use - Google Patents

Abstract

Disclosed are a vehicle (1) and method for spreading a particulate material (2) over a ground surface and a wetting apparatus (7) for wetting a particulate material (2). The disclosure notes that current vehicles and methods for spreading particulate material such as fertiliser are subject to inefficient spreading and lack in foliar uptake. The vehicle (1) comprises at least one store (3) of particulate material (2); spreading means (4); conveying means (6) and wetting apparatus (7). The spreading means (4) in the form of one or more spinning discs, a blower or an oscillating spout to spread the particulate material (2) over the ground surface. The conveying means (6) conveys the particulate material (2) from the at least one store (3) to the spreading means (4). The wetting apparatus (7) wets the particulate material (2) or during the act of spreading of the particulate material (2) over the ground surface by the spreading means (4). cient spreading and lack in foliar uptake. The vehicle (1) comprises at least one store (3) of particulate material (2); spreading means (4); conveying means (6) and wetting apparatus (7). The spreading means (4) in the form of one or more spinning discs, a blower or an oscillating spout to spread the particulate material (2) over the ground surface. The conveying means (6) conveys the particulate material (2) from the at least one store (3) to the spreading means (4). The wetting apparatus (7) wets the particulate material (2) or during the act of spreading of the particulate material (2) over the ground surface by the spreading means (4).

Description

WETTING APPARATUS AND METHOD OF USE FIELD This invention relates to wetting apparatus and method of use of same.

The invention may be particularly suitable for wetting a stream of particulate materials, such as fertiliser or agricultural lime, prior to, and/or during, the spreading of the particulate material by an appropriate ground spreading vehicle. For convenience only therefore, the invention will be predominantly described in relation to such use.

However, it is to be understood and appreciated that the invention may also have other users or applications, for example in relation to the aerial spreading of fertilisers or for wetting agricultural seeds prior to the spreading of same. The prior art, and possible applications of the invention, as described below, are therefore given by way of example only.

BACKGROUND Farmers and horticulturists generally want their pastures and crops to grow as fast as possible, and as a result fertilisers are commonly applied to the pastures or soil, at various times, to both replenish the pasture/soil with nutrients and/or to maximise the production of pasture or plant growth.

In New Zealand, over two million tonnes of fertiliser are applied annually to pastures, crops and forests, and about 75% of this total is spread by ground spreading vehicles such as tractors, trucks and quad bikes. The remaining 25% is spread by aerial vehicles such as fixed wing top dressing aircraft and helicopters.

The most common type of ground spreading vehicles utilise a spinning disc(s) to spread the fertiliser. Fertiliser is dropped, or fed, onto the spinning disc(s), that is/are usually fitted with several radial vanes, from which the fertiliser particles are flung horizontally.

Single disc diameters are usually about 750mm – 1000mm, and typical speeds range from 750 to 1,000 revolutions per minute (rpm).

Many spreaders of this type utilise two discs rotating in opposite directions, with the fertiliser being fed to each spinning disc via two separate conveyors (one for each spinning disc), such as chain belts or rubber belts – or alternatively via a single conveyor which conveys the fertiliser to a splitter above the two spinning discs.

Spinning disc spreaders are robust, and can handle a wide range of fertilisers and application rates. Swathe widths vary according to the size of fertiliser particles, their density, the design of the disc(s), and the revolutions per minute of the discs. As an example, a 4-5 mm diameter particle usually travels about 15-25 meters at 750rpm, compared to 15-20 meters for 1- 2 mm particles.

Other (less common) ground spreading apparatus for fertiliser include an oscillating spout (which comprises a spout that moves rapidly from side to side) and a blower (which simply blows the fertiliser particles from the back, or to the side, of the spreading vehicle).

There are several problems or difficulties associated with the ground spreading of fertilisers.

Firstly, many fertilisers consist, in whole or in part, of fine powders, and as a result any wind present can disrupt spreading by causing drift which results in the uneven spreading of fertilisers. Furthermore, fertiliser drift during spreading can pose health and environmental pollution problems, as well as economic loss.

In an attempt to address the problem of wind drift during spreading, fertilisers are often formed into granules or prills, which are much easier to spread in windy conditions. That is, the increased size and/or weight of the particles make them less susceptible to wind drift. They can also be spread in a wider swathe, resulting in less passes by the spreading vehicle.

However, a disadvantage associated with using granules is that they do not generally permit substantial foliar uptake (and in fact are often designed to avoid this). The granules are usually relatively large (most commonly 4-5mm), deliberately dry and very smooth, and hence the granules tend to roll off the plant foliage and onto the ground – and hence they are only generally available for uptake through the roots. Many nutrients, particularly nitrogen (N) in urea form, and many trace elements, can be far more efficient if given the opportunity for foliar uptake.

Another problem with granules of this size is that the spacing between the applied granules is often too large, at required application rates, for every plant to have even access to the nutrients being applied. Also, forming or manufacturing granules can be very expensive.

Also, the high spreading swath capability of granulated fertilisers, spread from conventional spreading vehicles, is often not able to be fully utilised on dairy farm paddocks which can be quite narrow, requiring the discs to be run at speeds that are two low for optimum spreading evenness.

Furthermore, present apparatus/methods for the ground spreading of fertilisers do not allow for certain chemicals to be added to the fertiliser and/or to be applied at the same time as spreading the fertiliser. That is, it is not currently possible to add additives or adjuvants, dissolved in water, for example to supply additional nutrients/benefits and/or to reduce surface tension (which allows for powders or mini-granules to spread out more easily and evenly over the foliage).

Examples of suitable adjuvants include (but are not limited to) growth proponants such as gibberellic acid (GA and salts thereof), and fertiliser efficiency enhancers such as such as nitrification and urease inhibitors, and lime-sparing products, and products to treat soil metal toxicities.

Perhaps in recognition of some of the above problems or difficulties, there are several prior art apparatus/methods for the wetting of fertilisers prior to them being spread or applied.

Some of these involve manufacturing liquid fertilisers in a factory, prior to them being spread, primarily in suspension, fluid or solution form. However, the manufacturing of such solutions can be expensive and therefore adds to the total cost of applying fertiliser.

These types of products also require specialised tankers to do the spreading, and furthermore the high water content of such products means that more frequent trips back to the depot to refill are often required.

NZ Patent No. 568608 describes a particulate spreading apparatus (included as part of the ground spreading vehicle) which has a mixing chamber for pre-mixing the particulate material with a liquid (such as water), prior to the liquid mixture subsequently being spread as a thick liquid or fluid from the back of the vehicle. However, a disadvantage associated with NZ 568608 is that the provision of a mixing chamber, and liquid mixture spreading means, on the spreading vehicle, adds cost and considerable complexity to the whole operation, and there are also more components that may break down and/or require more regular servicing or cleaning. Furthermore, the spreading apparatus described in NZ 568608 requires a specialised hopper to be built, that is, the apparatus cannot be fitted to an existing ground spreading vehicle.

NZ Patent No. 554915 is similar to NZ 568608, except that NZ 554915 also includes a grinding or crushing means within the mixing chamber, which is adapted to crush up the fertiliser prior to (or during) the addition of the liquid. The fertiliser/water mix is nonetheless still spread in liquid form, as per NZ 568608, and the disadvantages outlined above for NZ 568608 apply also to NZ 554915.

A further problem associated with both NZ 568608 and NZ 554915 is that the spreading apparatus for the liquid spreading of fertilisers possess very limited spreading swaths, meaning that the spreading vehicle has to drive up and down a paddock at closer intervals, thereby taking more time and incurring higher costs US 6,070,814 Deitesfeld describes a hand-held seed/fertiliser spreader which has a receptacle in which the seed/fertiliser is stored. The seed/fertiliser mix is sucked out of the receptacle and blown out through an outlet hose, whilst being wetted from behind by one or more water nozzles near the outlet. However, a disadvantage associated with Deitesfeld is that it is a small hand-held device that is only suitable for use with small areas such as private lawns and gardens. The device is therefore not adapted to be fitted (or be attachable) to a fertiliser ground spreading vehicle. Furthermore, the seed/fertiliser mix is only wetted from behind after it has been discharged from the outlet, and this is an inefficient and ineffective way of wetting the particulate material - because the water nozzles are positioned behind the outlet, and spray water in the same direction as the rapidly flowing stream of seed/fertiliser mix. The application of the water to the seed/fertiliser mix would be much more efficient if the water nozzles were directed across the rapidly moving stream of the seed/fertiliser mix, rather than behind, and parallel, to the particulate stream.

US 5,242,120 Barber et al describes a distribution system for fertilisers that has two hoppers, each containing a different type of fertiliser. The two fertilisers are mixed and subsequently pass up through a channel where the mixture is wet, prior to being spread or applied. The mixture moves through the channel by the use of an auger. A disadvantage associated with Barber is that the distribution system is complex, and therefore expensive, and furthermore the system cannot be fitted to an existing fertiliser ground spreading vehicle. Also, the use of an auger creates problems because augers do not always work effectively with wetted materials. That is, they may become blocked which means the auger works less efficiently and/or requires regular cleaning or maintenance.

Furthermore, wetted particulate materials, driven by augers, tend to segregate, and especially if the mixture contains particulate material of different sizes. Hence, the mixture of the two fertilisers may separate and be applied or spread in clumps of each fertiliser, rather than as a mixture of the two fertilisers. This is clearly unsatisfactory.

It may be of advantage therefore if there was available wetting apparatus (and/or method of use of same) which was effective for wetting fertilisers prior to, and/or during, the spreading of the fertilisers by a vehicle, and/or for encouraging or maximising foliar uptake of the fertilisers, and preferably without the need for specialised and/or expensive and/or complicated apparatus or machinery.

It may also be of benefit if such apparatus (and method of use of same) allowed for the application of certain adjuvants at the same time that the fertiliser is being spread.

It may also be of advantage if the wetting apparatus (and/or method of use of same) could be easily and readily fitted to existing fertiliser spreading vehicles.

OBJECT It is one object of the present invention to provide a vehicle for spreading a particulate material over a ground surface, which goes some way towards addressing one or more of the above problems or difficulties, or which at the very least provides the public with a useful choice.

It is a further object of the present invention to provide a wetting apparatus, and method of use, which goes some way towards addressing one or more of the above problems or difficulties, or which at the very least provides the public with a useful choice.

DEFINITIONS Throughout this specification unless the text requires otherwise, the word 'comprise' and variations such as 'comprising' or 'comprises' will be understood to imply the inclusion of a stated integer or step or group of integers or steps but not the exclusion of any other integer or step or group of integers or steps.

Throughout this specification, the term “fertiliser(s)” is to be understood to include all dry powder or granulated fertilisers, as well as agricultural lime.

STATEMENTS OF INVENTION According to one aspect of the present invention, there is provided a vehicle for spreading a particulate material over a ground surface, said vehicle including: a) at least one store of a particulate material, b) a spreading means for spreading the particulate material over the ground surface, c) a conveying means for conveying the particulate material from the at least one store to the spreading means, d) wetting apparatus for wetting the particulate material during the act of spreading the particulate material over the ground surface, by the spreading means.

The particulate material may be any particulate material that is required, or desired, to spread over the ground surface.

Preferably, the particulate material may be a fertiliser, or a mix of fertilisers, and preferably one or more fine-particle, or mini-granulated, fertiliser(s) and/or lime.

Examples include, but are not limited to, single and triple superphosphate (SSP and TSP), di-ammonium and mono-ammonium phosphate (DAP and MAP), urea (crystalline or prilled), lime, and reactive phosphate rock (RPR).

The particulate material may also comprise, or include, agricultural seeds, growth promotants and fertiliser efficiency additives.

The ground surface may be a paddock, or pasture, or a ploughed field in which crops are to be planted (or which have been planted).

The vehicle may be any suitable vehicle for spreading the particulate material over the ground surface. Preferably, the vehicle may be motorised, and examples include trucks, tractors, and quad bikes. It is also envisaged that the vehicle could be a towed trailer, for example a trailer towed behind a truck, tractor or quad bike.

In an alternative embodiment, it is envisaged that the vehicle could be an aerial vehicle, such as a fixed wing top dressing aircraft or a helicopter.

Preferably, the at least one store of the particulate material may be one or more hoppers, housed on or within the vehicle. However, any other suitable storage container for the particulate material may be utilised, as required or as desired.

Preferably, the spreading means may be in the form of one or more spinning discs mounted on the rear of the vehicle. Such spreading means are well known, and are in common usage for the spreading of particulate material, such as fertilisers.

Alternatively, the spreading means may be in the form of an oscillating spout, which comprises a spout that moves rapidly from side to side.

Alternatively, the spreading means may be in the form of a blower, which simply blows the particulate material from the back (or side) of the spreading vehicle.

The conveying means may be any suitable means for transporting the particulate material from the store of particulate material, to the spreading means.

In the case of the spreading means being one or more spinning discs, the conveying means may include an auger, preferably housed within a suitable channel, which transports the particulate material from the store of particulate material to the spreading means (that is, to the spinning discs).

Alternatively, the conveying means may be one or more chain belts or rubber belts.

Alternatively, and preferably, the conveying means may be in the form of at least one conveyor belt, which is adapted to transport the particulate material from the store of particulate material to the spinning disc(s) of the spreading means.

In the case of the spreading means being an oscillating spout, the conveying means may be in the form of an auger or pump, for conveying the particulate material from the store of particulate material to the oscillating spout.

In the case of the spreading means being a blower, the conveying means may be in the form of a conveyor belt, for conveying the particulate material directly from the store of particulate material to, and/or out of, the blower.

In a simple form of the invention, the particulate material may be simply blown out the back of the vehicle, for example by a blower (or possibly an oscillating spout). In such an embodiment, the wetting apparatus may include a pipe extending across the rear of the vehicle, the pipe including a number of apertures through which a wetting fluid may be dispensed, preferably under pressure and in a fan pattern or a wide swathe. In such an embodiment, it may be appreciated that the particulate material has to pass through the wetting fluid, as it is being spread. thus wetting the particulate material, during the process of being spread.

Preferably, the wetting fluid may be water.

Preferably, adjuvants, and/or other additives, may be added to the water, as required or as desired. For example, additives (in liquid or dissolvable powder form) may be added to the store of wetting fluid which provide additional nutrients and/or which reduce surface tension (which allows for powders or mini-granules to spread out more easily and evenly over the foliage). An advantage of adding such additives is that is allows the additives to be applied at the same time as the fertiliser is being spread. This saves time and cost, as otherwise the additives would have to be applied separately, and most likely by a separate vehicle and/or contactor. Examples of suitable adjuvants have been described previously.

According to another aspect of the present invention, there is provided a vehicle for spreading a particulate material over a ground surface, substantially as described above, wherein the wetting apparatus includes a housing, through which the particulate material must pass prior to reaching the spreading means, the housing being provided with wetting means adapted to wet the particulate material as it passes through the housing, and prior to being spread by the spreading means.

In such an embodiment, the conveying means may convey the particulate material into a first opening in the housing, and the subsequently wetted particulate material may exit from the housing, to the spreading means, via a second opening in the housing.

Preferably, the housing may be wholly or partially situated below the level of the conveying means, and above the level of the spreading means, whereby the particulate material passes through the housing, and subsequently on to the spreading means, under the force of gravity.

In another embodiment, the housing may be partially or wholly situated on the truck.

Preferably, the housing may include a vibration means to vibrate the housing, and therefore the particulate material within the housing, during operation of the vehicle and/or the wetting apparatus. The vibration means may serve to keep the particulate material in an agitated or airborne state and/or to prevent the particulate material from settling on the bottom of the housing. In this fashion, the wetting apparatus or wetting means will be much more effective in maximising the wetting of the entirety of the particulate material, as compared to the vibration means not been present.

In one embodiment, the housing may be fully enclosed (with an opening at each end).

Alternatively, the housing may be partially enclosed, for example in the form of a U- shaped channel.

Preferably, the wetting apparatus may be adapted to be fitted to an existing vehicle, which is ordinarily used for the spreading of a particulate material over a ground surface.

An advantage of such an arrangement is that a specialised vehicle (or hopper with wetting and/or mixing and/or crushing chambers) is not required - unlike NZ 568608, NZ 554915 and US 5,242,120, described previously.

Preferably, the wetting apparatus may be supported by the same support means by which the spreading means is attached to the rear of the vehicle.

Preferably, the wetting means may include one or more spray jets or nozzles, which pass into or through the housing, with the spray jets or nozzles being in communication with a store of wetting fluid, such as a water tank. There may also be provided a water pump to pump the fluid from the water tank to the spray jets or nozzles, and preferably under pressure. The water tank may preferably be housed on or within the vehicle.

The water tank may be of any size, but preferably it may be approximately 5 – 25% of the volume of the store of particulate material, and preferably around 10%.

In such an embodiment, as described above, it may be appreciated that the particulate material is wetted prior to the particulate material reaching the spreading means, where it is subsequently spread on or over the ground surface.

The spreading means and/or the conveying means and/or the vibration means and/or the means for supplying water to the wetting means may preferably be powered by the vehicle. Alternatively, they may be powered by a separate motor, for example an electric motor. The electric motor may be powered by, and/or recharged by, the motor of the vehicle.

According to another aspect of the present invention, there is provided a vehicle for spreading a particulate material over a ground surface, substantially as described above, wherein the wetting apparatus includes an upper deck member and a lower deck member, with the upper deck member being positioned above the spreading means, and the lower deck member being positioned below the spreading means, the arrangement and construction being such that one or both of the upper and lower deck members are provided with wetting means adapted to wet the particulate material during the spreading of the particulate material by the spreading means.

In such an embodiment, the spreading means may preferably be positioned below the level of the conveying means, whereby the particulate material passes from the conveying means to the spreading means under the force of gravity.

Preferably, the wetting apparatus may be adapted to be fitted to an existing vehicle, which is ordinarily used for the spreading of a particulate material over a ground surface.

And again, such an arrangement has advantages over NZ 568608, NZ 554915 and US ,242,120, as described above.

Preferably, the wetting apparatus may be supported by the same support means by which the spreading means is attached to the rear of the vehicle.

Preferably, the wetting means includes one or more spray jets or nozzles housed on or within the upper and/or lower deck members, the spray jets or nozzles being in communication with a store of wetting fluid, such as a water tank. There may also be provided a water pump to pump the fluid from the water tank to the spray jets or nozzles, and preferably under pressure. The water tank may preferably be housed on or within the vehicle.

Preferably, the spray jets or nozzles of the upper deck member may direct the wetting fluid in a downward direction towards the spreading means (and the ground) and/or the spray jets or nozzles of the lower deck member may direct the wetting fluid in an upward direction towards the spreading means.

In one embodiment, only the upper deck member or only the lower deck member may be provided with wetting means.

In an alternative, and preferred, embodiment, both the upper deck member and the lower deck member may be provided with wetting means (in this fashion, the wetting apparatus or wetting means should be much more effective in maximising the wetting of the entirety of the particulate material during the spreading of same).

In such an embodiment, as described above, it may be appreciated that the particulate material is wetted during the act of the particulate material being spread on or over the ground surface. Such a method may have a slight advantage over the method where the particulate material is wetted prior to being spread because the wetting apparatus does not have to convey or transport the wetted material through the housing, and on to the spreading means (as described previously). Instead, the particulate material is simply wetted as it is being spread. Hence, any means to assist in the movement of the wetted particulate material through the housing, such as vibration means, are not required.

According to another aspect of the present invention, there is provided a vehicle for spreading a particulate material over a ground surface, substantially as described above, wherein the wetting apparatus is adapted to wet the particulate material both prior to the spreading of the particulate material by the spreading means, and during the spreading of the particulate material, by the spreading means.

In such an embodiment, there may be provided a first wetting apparatus adapted to wet the particulate material prior to the spreading of the particulate material, and a second wetting apparatus adapted to wet the particulate material during the spreading of the particulate material.

The first and second wetting apparatus may be substantially the same as the two wetting apparatus described previously, or they may be of a different configuration.

According to another aspect of the present invention, there is provided a method of spreading particulate material over a ground surface, the method including the step of using the vehicle, substantially as described above, to spread the particulate matter over the ground surface.

The encouraging or maximising of foliar uptake of fertiliser is achieved through a combination of two factors. The first factor is the preferred use of a wholly or partly fine- particle fertiliser such as prilled urea, poorly granulated super phosphate, agricultural lime, RPR and/or various trace elements.. Because a fine material or mini-granulated product such as prilled urea have more surface area to react, as compared to larger particulates such as granules, the use of a fine-particle fertiliser serves to encourage or maximise the foliar uptake of the fertiliser. The second factor is the wetting of the fertiliser by the wetting apparatus or wetting means. This ensures that the fertiliser particles are wet enough to adhere to the surface of the leaves of the crop or pasture that the fertiliser is being applied to, so that the fertiliser particles will therefore have the maximum time or opportunity to dissolve on the surface of the leaves, thereby facilitating entry of the nutrient or nutrients in the fertiliser particles and/or adjuvants to pass directly into the plant.

According to another aspect of the present invention, there is provided a wetting apparatus for wetting a particulate material prior to the spreading of the particulate material over a ground surface, by a vehicle, said wetting apparatus being substantially as described above.

According to another aspect of the present invention, there is provided a wetting apparatus for wetting a particulate material during the spreading of the particulate material over a ground surface, by a vehicle, said wetting apparatus being substantially as described above.

PREFERRED EMBODIMENTS The descriptions of the preferred forms of the invention to be provided herein, and with reference to the accompanying drawings, are given purely by way of example, and are not to be taken in any way as limiting the scope or extent of the invention.

DRAWINGS Fig 1: is a simplified schematic side view of a first possible embodiment of a vehicle for spreading a particulate material over a ground surface, Fig 2: is a close up view of the wetting apparatus depicted in Fig 1, Fig 3: is a simplified schematic side view of a second possible embodiment of a vehicle for spreading a particulate material over a ground surface, and Fig 4: is a simplified schematic side view of a third possible embodiment of a vehicle for spreading a particulate material over a ground surface.

DESCRIPTION OF PREFERRED EMBODIMENT Having regard to Figs 1 and 2, there is depicted a vehicle 1 for spreading a particulate material 2 over a ground surface, such as a paddock or pasture.

The particulate material 2 is a fertiliser called prilled or mini-granulated urea (treated with nitrification and/or urease inhibitors), although any other type of fertiliser may be utilised.

The vehicle 1 is a standard fertiliser spreading truck, and includes a standard spreading means in the form of a spinning disc 4.

The spinning disc 4 is attached to the truck 1 by the support frame 8. The spinning disc 4 has a number of radial vanes 9, from which the fertiliser particles 2 are flung horizontally, in a swathe of approximately 15m from the spinning disc 4. There is also provided a motor 5 for powering the spinning disc 4. The motor 5 is operatively connected to the engine (not shown) of the truck 1. The diameter of the spinning disc 4 is approximately 750mm, and the spinning disc 4 is adapted to rotate at a speed of approximately 750 - 1000 revolutions per minute.

The truck 1 also includes a store of fertiliser 2, in the form of a hopper 3, housed on the back of the truck 1.

The truck 1 also includes a conveying means in the form of a conveyer belt 6. The conveyor belt 6 is adapted to transport or convey the fertiliser 2 from the hopper 3 to the spinning disc 4.

There is also provided wetting apparatus generally indicated by arrow 7. The wetting apparatus 7 is adapted to wet the fertiliser particles 2 prior to the spreading of the fertiliser particles 2 over the ground surface, by the spinning disc 4.

The wetting apparatus 7 includes a housing 10, through which the fertiliser particles 2 must pass prior to reaching the spinning disc 4. The housing 10 is fitted to the existing support frame 8 by the strut 11. The housing 10 is a hollow, rectangular shaped box, which extends longitudinally (and at a slightly downward angle) between the rear of the truck 1 and the spinning disc 4.

The housing 10 includes a first opening 12, into which the fertiliser 2 is fed, via the conveyor belt 6, and a second opening 13 where the wetted fertiliser 2 exits the housing and falls onto the spinning disc 4.

The housing 10 is mostly (or partially) situated below the level of the conveyor belt 6, and above the level of the spinning disc 4, whereby the fertiliser 2 passes into and through the housing 10, and subsequently on to the spinning disc 4, under the force of gravity. This is of significant advantage because it does away with the need for complex or expensive pumping equipment, or augers, such as those described in NZ 568608, NZ 554915, US 5,242,120 and US 5,242,120.

The housing 10 is provided with wetting means in the form of spray nozzles 14. In the embodiment shown, there are three spray nozzles 14, although any number may be utilised, and they may be positioned on any wall or surface of the housing 10. As can be seen from Fig 2, water is sprayed by the three nozzles 14 in two directions, namely with one spray nozzle spraying water at 90° to the other two spray nozzles.

The spray nozzles 14 are fluidly connected to the water tank 15, via the water pipe 16.

The water tank 15 is filled with water and may be housed within the hopper 3 or mounted on the outside of the hopper 3, and/or on the rear deck of the truck 1. The water supplied to the spray nozzles 14 from the water tank 15, is supplied under pressure. There is provided an electric motor or pump (not shown) for facilitating this, the motor or pump being powered and/or recharged by the engine of the truck.

The housing 10 includes a vibration means in the form of the vibrating box 17, which is attached to the underside of the housing 10. During operation of the truck 1 and/or the wetting apparatus 7 the vibrating box 17 is actuated. The vibrating box 17 vibrates the housing 7, which serves to keep the (dry or wetted) fertiliser particles 2 in an agitated or airborne state, and therefore prevents the fertiliser particles 2 from clumping together and/or settling onto the bottom of the housing 10. It will also be appreciated that having the fertiliser particles 2 airborne will result in a more effective wetting of the fertiliser particles 2, as compared to the fertiliser particles 2 merely flowing over the bottom of the housing 10. Thus, the vibrating box 17 serves to maximise the effectiveness of the wetting of the fertiliser particles 2. The vibrating box 17 includes an electric motor (not shown) which is powered and/or recharged by the engine of the truck.

One advantage associated with the use of the wetting apparatus 7 is that it may be easily and readily fitted to an existing fertiliser spreading truck 1. Namely, the housing 10 may be bolted onto the frame 8, via the strut 11. The tank 15 may also be fitted to, or within, the truck 1, and fluidly connected to the housing 10. A pump or motor may also be added in order to pump water from the water tank 15 to the spray nozzles 14. This is a relatively simple and inexpensive procedure, and is certainly much easier and cheaper to do, as compared to purchasing or employing the use of a specialised spreading vehicle, such as those described in NZ 568608, NZ 554915 and US 5,242,120. Furthermore, the wetting apparatus 7 employs very few moving parts and/or would not be susceptible to breaking down or clogging up. Hence, the time required to be spent servicing and/or cleaning the wetting apparatus 7 is minimal or negligible. This represents a further advantage over the prior art referred to above.

The method of use of the vehicle 1 and/or the wetting apparatus 7 is as follows.

Firstly, the hopper 3 of the truck 1 is filled with fertiliser 2, and the water tank 15 is filled with water. The truck 1 then begins its various passes over the paddock or pasture, as per normal. The fertiliser 2 is conveyed into the first opening 12 of the housing 10, via the conveyor belt 6, where it is agitated via the vibrating box 17, and wetted via the spray nozzles 14. The wetted fertiliser 2 then passes on to the spinning disc 4 where it is spread over the ground surface.

The wetting of the fertiliser particles 2 causes the dust component of the product present to adhere to larger wetted particles during the wetting, which assists in reducing both spray and dust drift and yet increases the chance of the fertiliser particles 2 adhering to the foliage, thus increasing the uptake of the fertiliser by the foliage.

The primary purpose of the spray-wetting is therefore to make the fertiliser particles 2 wet enough to adhere to the surface of the leaves of the crop or pasture it is being applied to, so that the fertiliser particles 2 will have the opportunity to dissolve on the surface of the leaf, thereby facilitating entry of the nutrient or nutrients in the fertiliser particles 2 and/or any relevant additives or adjuvants to pass directly into the plant.

For nutrients and additives that can be taken through the leaves, this is generally far more energy-efficient than root uptake for the plant, particularly in the case of nitrogen fertilisers such as prilled urea; soluble magnesium and trace elements; and growth stimulants such as gibberellic acid. Any nutrient applied in excess of the ability of the plant to take it directly into the leaves, or any nutrient such as the phosphorus (P) in slow- release RPR that is not able to be taken up through the leaves, will fall through the foliage to the ground as it dries, or be washed there by rainfall or irrigation, where it will be commence dissolution by soil acids and microbes into forms available for root uptake.

It is often desirable to have both modes of uptake occurring, and for this reason it is not necessary to ensure that all fertiliser particles 2 are of a particular size. The appropriate level of moisture to add to the fertiliser particles 2 will typically be in the range of 5-10% w/w. This small amount will not adversely affect the evenness of spread of the fertiliser In some cases it will be preferable to dissolve any additives/adjuvants in the water being used for wetting the fertiliser particles 2, and especially in the case of trace elements or additives that are easily dissolved in water.

The most important aspect therefore, of this methodology is that it encourages or maximises foliar uptake of the fertiliser 2, and is certainly much more effective in this regard as compared to conventional fertiliser spreading techniques, which do not involve wetting the fertiliser 2.

This is primarily due to two factors, summarised as follows: The first factor is that the invention conveniently allows for the preferred use of dry- stored fine-particle products such as RPR or lime, or poorly granulated fertilisers such as some superphosphates, trace elements and perhaps most importantly prilled (mini- granulated) urea. Such fertilisers are preferred by many farmers for a variety of reasons depending on the fertilisers being used. However, and as described previously, a difficulty associated with using fine-particle fertilisers containing a significant dust component is that they are susceptible to wind drift, which results in uneven spreading of the fertiliser, as well as posing health and environmental pollution problems (such as by direct entry into waterways) and causing economic loss (by virtue of the farmer paying for a significant amount of fertiliser which may not reach its intended target).

As a result of the wind drift problems associated with using very fine-particle fertilisers, many farmers (reluctantly) use fertilisers formed into granules or prills, which are heavier and are therefore much easier to spread in windy conditions. However, a disadvantage associated with using granules is that they do not generally permit substantial foliar uptake, which can be a very efficient mode of uptake for many nutrients and additives.

Normal granules are relatively large and/or heavy, and easily roll off the plant foliage even if wetted, and any remaining are easily washed off the foliage by rain, where they fall through to the ground – and hence are only available for root uptake (which may not be the preferred uptake method for a particular fertiliser).

Another problem with granules is that the spacing between the applied granules is often too large, at required application rates, for every plant to have even access to the nutrients being applied. Also, forming or manufacturing granules can be very expensive.

Hence, the present invention allows farmers to use the more preferred very fine-particle fertilisers, because the slight wetting of the fertiliser 2 makes the fertiliser 2 much less susceptible to wind drift.

The second factor (which is the more important of the two) is that the wetting of the fertiliser by the wetting apparatus 7 ensures that the fertiliser particles 2 are wet enough to adhere to the surface of the leaves of the crop or pasture that the fertiliser 2 is being applied to, so that the fertiliser particles 2 will therefore have the maximum time or opportunity to dissolve on the surface of the leaves, thereby facilitating entry of the nutrient or nutrients in the fertiliser particles 2 and/or additives to pass directly into the plant. Hence, it may be appreciated that the invention encourages or maximises the foliage uptake of fertiliser 2.

Fig 3 illustrates another possible embodiment of a truck 1 for spreading fertiliser 2 over a ground surface. For convenience only, the same numbers will be used for referring to features of the embodiment illustrated in Fig 3, which are equivalent to the features illustrated in Figs 1 and 2.

In the embodiment illustrated in Fig 3, the wetting apparatus 7 includes an upper deck member 20 and a lower deck member 21, with the upper deck member 20 being positioned above the spinning disc 4 (spreading means), and the lower deck member 21 being positioned below the spinning disc 4.

The upper and lower deck members 20, 21 comprise circular (or semi-circular) hollow housings, which are bolted onto the support frame 8.

The upper and lower deck members 20, 21 are fluidly connected to the water tank 15 situated on the truck 1. There is also provided a water pump (not shown) for providing water from the water tank 15 to the upper and lower deck members 20, 21, under pressure.

The underside of the upper deck member 20 is provided with wetting means in the form of spray nozzles 22. Likewise, the topside of the lower deck member 21 is provided with wetting means in the form of spray nozzles 23.

The spray nozzles 22 are adapted to spray water in a downward correction towards the top of the spinning disc 4 (and towards the ground surface), and the spray nozzles 23 are adapted to spray water in an upward direction towards the underside of the spinning disc 4. Furthermore the spray nozzles 22, 23 are staggered or in a dove-tail pattern. This is to ensure that the water fans created by the nozzles 22, 23 are substantial and/or cover a wide area, whereby the wetting of the fertiliser 2 is maximised and/or to ensure that the entirety of the fertiliser 2 is wetted.

In Fig 3, only minimal sprays or fans of water are shown, and this is for simplicity only, whereas in reality the sprays of water would cover all of the area between the upper deck member 20 and the lower deck member 21.

The arrangement and construction of the embodiment illustrated in Fig 3 is such that upper and lower deck members 20, 21 are adapted to wet fertiliser 2 during the spreading of the fertiliser by the spinning disc 4.

The method of use of the vehicle 1 and/or the wetting apparatus 7, illustrated in Fig 3, is as follows: Firstly, the hopper 3 of the truck 1 is filled with fertiliser 2, and the water tank 15 is filled with water. The truck 1 then begins its various passes over the paddock or pasture, as per normal. The fertiliser 2 is conveyed onto the spinning disk 4 via the conveyor belt 6, and the chute extension 24. As the fertiliser 2 hits the spinning disc 4, and is therefore spread out and over the ground surface, it is simultaneously wetted by water being sprayed by the spray nozzles 22, 23. Hence, the embodiment illustrated in Fig 3 serves to wet the fertiliser 2 during the spreading of the fertiliser 2 by the spinning disc 4. This is slightly different to the embodiment illustrated in Figs 1 and 2, where the wetting apparatus 7 serves to wet the fertiliser 2 prior to the spreading of the fertiliser 2 by the spinning disc 4. However, both embodiments result in substantially the same effect, and hence the advantages described previously in relation to the embodiment illustrated in Figs 1 and 2, also apply to the embodiment illustrated in Fig 3.

A further advantage associated with the embodiments illustrated in Figs 1 to 3 is that the spray nozzles 14, 22 & 23 spray water from more than one direction or orientation. This ensures that virtually all of the fertiliser particles 2 are wetted to some degree. Hence, there is less likelihood of any fertiliser particles 2 escaping a wetting from the water.

Hence, the present invention is significantly more efficient at wetting the entirety of the fertiliser particles 2, as compared to the prior art device described in US 6,070,814 (where the seed/fertiliser mix is only able to be wetted from behind, and where the water jets are sprayed in the same direction of travel as the seed/fertiliser mix).

In Figs 1 – 3, the fertiliser 2 is not shown being flung from the spinning disc 4. This is for simplicity only and to ensure that the drawings are not overly cluttered.

Fig 4 illustrates another possible embodiment of a vehicle 1 for spreading fertiliser 2 over a ground surface. For convenience only, the same numbers will be used for referring to features of the embodiment illustrated in Fig 4, which are equivalent to the features illustrated in Figs 1 – 3.

In the embodiment illustrated in Fig 4, the vehicle 1 is a trailer, which may be towed behind a motorised vehicle such as a truck or tractor or quad bike. Sitting on top of the trailer 1 is a water tank 15 and a fertiliser hopper 3.

The fertiliser 2 is fed via a conveyor belt (not shown) into a chute 25, where it falls onto a spinning disc 4 (spreading means) by the force of gravity. The fertiliser 2 is then spread over the ground surface. The spinning disc 4 is powered by the motor 5.

The trailer 1 includes a first wetting apparatus 26 and a second wetting apparatus 27.

Both the first and second wetting apparatus 26, 27 are fluidly connected to the water tank via piping 28. Water is supplied to both the first and second wetting apparatus 26, 27 under pressure, and there is provided a water pump 29 to facilitate this.

The first wetting apparatus 26 includes a spray nozzle (not shown) which produces a swathe or fan of fine water droplets, indicated by arrow 30. This fan of water 30 is adapted to wet the fertiliser particles 2 as they pass from the chute 25 to the spinning disc 4. Hence, the first wetting apparatus 26 is adapted to wet the fertiliser 2 prior to the spreading of the fertiliser 2 by the spinning disc 4.

The second wetting apparatus 27 includes a spray nozzle 31 which produces a swathe or fan of fine water droplets, indicated by arrow 32. This fan of water 32 is adapted to further wet the fertiliser particles 2 as they are being spread onto or over the ground surface by the spinning disc 4. Hence, the second wetting apparatus 27 is adapted to wet the fertiliser 2, during the spreading of the fertiliser 2 by the spinning disc 4.

Hence, the first wetting apparatus 26 and the second wetting apparatus 27 combine to wet the fertiliser 2 both prior to the spreading of the fertiliser 2 by the spinning disc 4, and during the spreading of the fertiliser 2 by the spinning disc 4.

The water pump 29 and motor 5 (and also the conveyor belt – not shown) may all be powered (and/or recharged) from the motorised vehicle which is towing the trailer 1.

It is envisaged that the embodiment illustrated in Fig 4 would be particular suitable for towing on a trailer behind a quad bike.

A farmer would therefore be able to easily and cheaply manufacture apparatus for wetting fertiliser 2, during the spreading of same, without having to hire a truck - as depicted in Figs 1 to 3. And the farmer could use his/her own trailer and farm vehicle for towing the trailer. Hence, a farmer would be independent and/or self-governing, in that the farmer would be able to apply fertiliser 2 to his/her paddocks as and/or when required or desired (rather than relying on when fertiliser spreading trucks may be available).

Furthermore, it may be appreciated that the embodiment illustrated in Fig 4 could be easily, readily, and cheaply manufactured, and incorporated onto the trailer 1.

A further advantage associated with the embodiment illustrated in Fig 4 is that the entire apparatus is relatively portable, whereby it could easily and readily be removed from the trailer 1, and incorporated onto another trailer. For example, a neighbouring farmer could borrow the apparatus and readily fit it to a trailer of his/her own.

A further advantage associated with wetting the fertiliser 2 both prior to, and during, the spreading of the fertiliser 2 by the spinning disc 4, is that it ensures that virtually all of the fertiliser particles 2 are wetted to some degree. Hence, there is less likelihood of any fertiliser particles 2 escaping a wetting from the water.

The embodiment illustrated in Fig 4 results in substantially the same effect (although in many cases it results in an improved effect) as the embodiments illustrated in Figs 1 to 3, and hence the advantages described previously in relation to the embodiments illustrated in Figs 1 to 3, also apply to the embodiment illustrated in Fig 4.

VARIATIONS While the embodiments described above are currently preferred, it will be appreciated that a wide range of other variations might also be made within the general spirit and scope of the invention, and/or as defined by the appended claims.

Claims (19)

I Claim:

1. A vehicle for spreading a particulate material over a ground surface, said vehicle including: a. at least one store of a particulate material, 5 b. a spreading means for spreading the particulate material over the ground surface, said spreading means being in the form of one or more spinning disks or in the form of an oscillating spout, c. a conveying means for conveying the particulate material from the at least one store to the spreading means, 10 d. wetting apparatus for wetting the particulate material during the act of spreading the particulate material over the ground surface, by the spreading means.

2. A vehicle, as claimed in Claim 1, wherein said at least one store of a particulate material is at least one hopper. 15

3. A vehicle, as claimed in Claim 1, wherein said conveying means is in the form of a conveyor belt, said conveyor belt being adapted to transport the particulate material from said at least one store to the spreading means.

4. A vehicle, as claimed in Claim 1, wherein the wetting apparatus includes an upper deck member and a lower deck member, with the upper deck member being 20 positioned above the spreading means, and the lower deck member being positioned below the spreading means, the arrangement and construction being such that one or both of the upper and lower deck members are provided with wetting means adapted to wet the particulate material during the spreading of the particulate material by the spreading means.

5. A vehicle as claimed in Claim 4, wherein the spreading means is positioned below the level of the conveying means, whereby the particulate material passes from the conveying means to the spreading means under the force of gravity.

6. A vehicle, as claimed in Claim 4 or Claim 5, wherein the wetting apparatus is 5 adapted to be fitted to an existing vehicle, which is ordinarily used for the spreading of a particulate material over a ground surface.

7. A vehicle, as claimed in any one of Claims 4 to 6, wherein the wetting means includes one or more spray jets or nozzles housed on or within the upper and/or lower deck members, said spray jets or nozzles being in communication with a 10 store of wetting fluid.

8. A vehicle as claimed in Claim 7, wherein the spray jets or nozzles of the upper deck member direct the wetting fluid in a downward direction towards the spreading means and/or the spray jets or nozzles of the lower deck member direct the wetting fluid in an upward direction towards the spreading means. 15

9. A vehicle as claimed in Claim 1, wherein there is provided a first wetting apparatus adapted to wet the particulate material prior to the spreading of the particulate material, and a second wetting apparatus adapted to wet the particulate material during the spreading of the particulate material.

10. A vehicle, as claimed in Claim 9, wherein the first wetting apparatus includes a 20 housing, through which the particulate material must pass prior to reaching the spreading means, said housing being provided with wetting means adapted to wet the particulate material as it passes through the housing, and prior to being spread by the spreading means.

11. A vehicle, as claimed in Claim 10, wherein the conveying means conveys the 25 particulate material into a first opening in the housing, and the subsequently wetted particulate material exits from the housing, to the spreading means, via a second opening in the housing.

12. A vehicle, as claimed in Claim 10 or Claim 11, wherein the housing is situated wholly or partially below the level of the conveying means, and above the level of the spreading means, whereby the particulate material passes through the housing, 5 and subsequently on to the spreading means, under the force of gravity.

13. A vehicle, as claimed in any one of Claims 10 to 12, wherein the housing includes a vibration means to vibrate the housing, and therefore the particulate material within the housing, during operation of the vehicle and/or the wetting apparatus.

14. A vehicle, as claimed in any one of Claims 10 to 13, wherein the wetting 10 apparatus is adapted to be fitted to an existing vehicle, which is ordinarily used for the spreading of a particulate material over a ground surface.

15. A vehicle, as claimed in any one of Claims 10 to 14, wherein the wetting means includes one or more spray jets or nozzles, which pass into or through the housing, said spray jets or nozzles being in communication with a store of wetting 15 fluid.

16. A vehicle as claimed in Claim 7 or Claim 15, wherein the store of wetting fluid is a water tank housed on or within the vehicle.

17. A vehicle as claimed in Claim 16, wherein said store of wetting fluid includes additives or adjuvants adapted to provide additional nutrients/benefits and/or to 20 reduce the surface tension of the wetting fluid.

18. A vehicle as claimed in any one of Claims 1 to 17, wherein the vehicle is selected from the list comprising; a truck, a tractor, a quad bike and a towed trailer.

19. A vehicle as claimed in any one of Claims 1 to 17, wherein the vehicle is an aeroplane.