GB2259637A - Spray booms - Google Patents

Abstract

A spray boom 18 for agricultural use is provided at its extremities with additional nozzles 28 and 30 connected to a separate tank 22 of herbicidal fluid in order to enable the user to treat a peripheral area, or sterile strip of a field at the same time as the crop is sprayed with the normal crop spray. The additional nozzles are preferably mounted on a resilient arm in order to avoid damage if they should strike an obstruction in their path during use. <IMAGE>

Description

CROP AND WEED CONTROL SPRAY DEVICE This invention relates to an arrangement for controlling unwanted herbal growth by spraying such growth area with a suitable herbicide or other control chemicals.

It has been recognised by farmers for some time that the ingress of weeds into the crop area almost always commences from the edge of the field or the hedgerow area.

Whilst it has been common to spray the crop area with a suitable fluid eg fertilizer or fungicide during certain stages of growth, a different and usually stronger weed killer is necessary to provide a so-called "sterile strip" between the hedgerow and the perimeter of the crop area. The effect of such a said "sterile strip" is to help keep the growing area substantially clean of weeds and hence prevent ingress into the crop area by re-seeding of those weeds, eg by thistledown or other seeds blown into the crop area, by root spread eg as in the case of couch grass of quich (agropyrum repense), or by layering eg by brambles or goose grass.

This gives considerable advantages insofar as it necessitates a lesser use of chemical spray over entire fields of crops during the growing season with consequent environmental and economical benefits.

A further benefit obtained from the creation of the "sterile strip" is found at harvest-time when the first pass round the perimeter of the field with a combine harvester is achieved much more quickly and easily due to a gross reduction in breakdowns and stoppages caused by brambles, cleavers and the like.

It is also found to be helpful in conserving wildlife which depends on the hedgerow environment for food and shelter and it is now recognised that the provision of a strip of sterile soil enables small creatures to have a clear, fast escape route from their predators and also provides a "runway" for larger birds to take off from and to land on. Wildlife is now seen to use the "sterile strip" to bask in the sunshine and dry itself after a storm.

It is common practice in agriculture, particularly in cereal farming, to arrange the seed drills such that at certain intervals two rows of such drills are stopped off from the seed supply so that the cereal crop provides a number of "tram lines" bare of cereals. These "tram lines" are arranged to be at intervals approximating to the distance between the wheels of the farmer's tractor is order that the tractor may be driven along the field for the purpose of spraying the crop without causing much damage to the growing crop. The tractor is, for this latter purpose, provided with means for mounting a spraying device which normally comprises a large tank and a spray boom extending a considerable distance on either side of the median line of the tractor.The tractor and its mounting has a pump operated by a motor-operated compressor and pipes connect with suitable nozzles located at intervals along the boom.

To create the "sterile strip" around the periphery of the field it has been the practice for a farmer to walk around the edge of the hedgerow with a knapsack or backpack mounted spray tank and a hand held nozzle. This method of spraying the hedgerow area is not only time consuming and laborious but carries the risk of inhalation by the farmer of possible toxic chemicals.

It has also been a practice at times to use a motorcycle fitted with one or more tanks containing the herbicide for use in spraying the "sterile strip" area. This method has its own hazards due to the difficult terrain over which the motorcycle has to travel.

It is an object of this invention to provide a method and means whereby the periphery of the crop field may be treated in a manner different from, but at the same time as the remainder of the field.

In accordance with the invention there is provided a spray device adapted for use with a conventional agricultural spray boom, wherein the device includes a tank capable of supplying a quantity of chemical spray substance, one or more pipes leading from the tank to one or more nozzles, and pressure means for conducting the spray substance from the tank to the nozzle or nozzles and control means for activating or de-activating the or each nozzle.

Preferably the device is used in conjunction with a system having a spray boom equipped with spray nozzles connected to a supply tank which is adapted to contain a liquid crop spray, and includes a further tank adapted to contain a herbicide, the further tank to be connected to at least one further spray nozzle located adjacent at least one outer end of the spray boom.

There may be more than one further spray nozzle towards each end of the spray boom and the further spray nozzles may be adjustable to regulate the area to be sprayed.

The further nozzles may be resiliently mounted adjacent the outer ends of the spray boom and the resilient mounting may comprise an arm pivoted intermediate its ends, an outer end of the arm providing a mounting for the nozzle or nozzles and a tension spring action between an anchor point on an inner end of the arm and a further anchor point on the spray boom.

The further tank may be provided with an electrically driven pump connected to a control switch.

The further tank may also be provided with an electrically driven agitator device adapted to agitate or stir the chemical solution in the tank.

There may be provided a switching system which incorporates means for actuating a visual or aural device, and this device may be mounted on a magnetic base adapted for installation within a tractor cabin.

One or more of the further nozzles may be connected to hand lance.

The invention further provides a method of providing or treating a sterile strip around an area for growing crops wherein a tractor-driven spray boom is traversed around the area and a herbicide liquid is sprayed from one or more nozzles located at one or both extremities of the spray boom to treat the sterile strip area.

One embodiment of the invention will now be described by way of example only with reference to the accompanying drawings in which Figure 1 is a plan view of a field being treated according to the invention; Figure 2 is a view of a tractor equipped with a conventional spray boom converted for use in accordance with the invention; Figure 3 is a diagrammatic front view of a conventional spray boom and its supply tank adapted in accordance with the invention; Figure 4 is a diagram of a control system for the spray equipment according to the invention; Figure 5 is a plan view of part of the spray boom showing mounting details of one of the further spray nozzles; and Figure 6 is a front elevation of the parts seen in Figure 5.

As seen in Figure 1 a typical cereal crop field is depicted having one boundary comprising a wall 2 and three further boundaries defined by a hedgerow 4 one of which has an access gate 6.

As is common in the industry, the cereal crop 7 is shown to provide pairs of so-called "tram-lines" 8 each pair being substantially the same distance apart as the wheels of the farmer's tractor. Thus the tractor may be used for example for towing an implement in the field of growing crops without damaging the crop unduly by merely guiding the tractor's wheels along the "tram lines".

In order to prevent or at least lessen the encroachment of weeds from the adjacent hedgerow into the growing crop area a "sterile strip" 10 is created between the hedgerow and the periphery of the crop. This strip is generally about one metre wide and, being devoid of weed and other growth, prevents ingress of weed into the crop area. This is now known to be also important to the preservation of wildlife by creating a fast escape route for small creatures from their natural predators and has also been seen to provide a "runway" or "landing strip" for larger birds to take off and land.

It is sometimes found to be advantageous to allow for a one metre width of "natural growth" between the hedgerow and the sterile strip.

As seen in Figure 2 a tractor designated generally as 12 is provided with a framework 14 on which is mounted a large tank 16 adapted to contain a liquid crop spray as used eg as a fertilizer and/or fungicide. The framework also supports a boom 18 as a mounting for a plurality of nozzles 20 connected by suitable pipes and tubes, not shown, to an outlet valve in the tank 16.

Further, mounted on the framework at the side of the tank 16 is a secondary vessel or tank 22 adapted to contain a suitable herbicide specifically formulated to give a high degree of weed control and suitable to kill off all herbaceous and other unwanted growth.

The tank 22 is connected by pipes 24 and 26 to nozzles 28 and 30 pivotally mounted for angular adjustment at the extreme ends of the boom 18. The vessel 22 is provided with a filler cap 32, a pump 34 and an agitator device 36 of conventional type.

As illustrated in Figure 4 a three-way solenoid control valve 38 is located between the pump 34 and the pipes 24, 26 and is actuated from a switch device 40 located conveniently in the cabin of the tractor 12. Thus, actuation of an appropriate rocker switch will cause the right-hand, or lefthand nozzle 28 or 30 to emit weed killer from the tank 22 or to switch the valve over to a position whereby no weed killer is passed to either pipe 24 or 26.

The power supply for the solenoid valve and the pump is taken from the electrical system in the tractor, although a separate battery could be mounted adjacent the secondary vessel if desired.

The switch may be arranged to isolate the entire secondary spray system, or to agitate the chemical solution in the tank 22. The latter arrangement is preferable before commencement of spraying by the secondary system.

The switch system may incorporate means for actuating a warning light and/or bleeper and may, if so desired, be mounted on a magnetic base for ready installation within the tractor cabin wherever is convenient to the operator.

In order to prevent damage to the nozzle or nozzles at the outermost end of the boom if it should strike an obstruction eg a fence post or thick branch of vegetation, there is provided a resilient mounting 40 comprising an arm 42 pivoted intermediate its ends on a pivot pin 44 which is fast in an extension 46 to the boom 18.

The nozzle 28 or 30 is mounted beneath the outermost end of the arm 42 and a shield 48 surrounds the nozzle area and is welded to the arms as seen clearly in figures 5 and 6.

A tension spring 50 extends between a spring pin 52 on the innermost end portion of the arm 42 and a further spring pin 54 fast on the extension 46 of the boom. Thus, if the shield 48 strikes an obstruction eg part of a hedgerow or a post, the arm 42 will rock about its pivot pin 44 extending the spring 50. When the obstruction is passed the spring will cause the arm 42 to return to its normal position with the axes of the pins 52, 54 and pivot pin 44 in longitudinal alignment.

As seen clearly in Figure 6 the nozzle 30 may be multiheaded, and each head may be adjustable with respect to the other head in order to define the area of the "sterile strip" being sprayed.

In use the farmer drives tractor with the spray boom and container 16 around the periphery of the field to spray the outermost area of growing crop with conventional liquid fertilizer/fungicide. On this first circumnavigation the solenoid valve is actuated by the switch control to cause the chemical treatment formulation contained in the tank 22 to be sprayed through either the nozzle 30 or 28 whichever is nearest to the desired "sterile strip". Thus, the treatment of that strip is carried out at the same time as the crop area adjacent the strip is being treated with the contents of the tank 16. After the first circumnavigations of the field the feed from the tank 22 is isolated and normal spraying from tank 16 proceeds alone.

The secondary spray system may of course be used on its own particularly before the initial sowing of the crop seed by simply actuating the appropriate nozzle 28 or 30 by the solenoid valve 38 and eliminating the spray system which utilizes the nozzles 20.

The spray system according to the invention is found to provide a simple yet effective way of treating the "sterile strip" area in a time and cost effective manner.

Although the invention has been described in relation to the spraying of a peripheral margin of a field the arrangement may also be utilized to advantage where occasional "spot treatment" of troublesome areas within the crop area is needed. Either one of the nozzles 28 or 30 may be connected by a flexible hose to a hand lance, and when the farmer meets such a troublesome area of stubborn weed growth not susceptible to the normal weed treatment available from the tank 16, he may then operate the control system as described with respect to Figure 4 to cause the chemical contained in the tank 22 to pass to the hand lance and manually direct the chemical to the said troublesome area.

Further, although there has been described an arrangement using secondary spray nozzles at each end of the spray boom, it may in practice be more economical to provide only one secondary spray nozzle, being affixed to only one end of the boom. This would be all that is necessary if it is the practice of the user to drive round his crop area in the same clockwise or anticlockwise direction. This would eliminate the cost of one set of secondary nozzles and their mounting plates, besides simplifying the valve system.

Claims (15)

1 A spray device adapted for use with an agricultural spray boom, wherein the device includes a tank capable of supplying a quantity of chemical spray substance, one or more pipes leading from the tank to one or each end of the spray boom and each terminating in one or more nozzles, pressure means for conducting the spray substance from the tank to the nozzle or nozzles and control means for activating or de-activating the or each nozzle.

2 A spray device according to claim 1 when used in conjunction with a system having a spray boom equipped with spray nozzles connected to a supply tank which is adapted to contain a liquid crop spray, the device including a further tank being connected to at least one further spray nozzle located adjacent at least one outer end of the spray boom.

3 A spray device according to claim 2 wherein there are provided more than one further spray nozzle towards at least one end of the spray boom and the further spray nozzles are adjustable to regulate the area to be sprayed.

4 A spray device according to claims 2 or 3 wherein the further nozzles are resiliently mounted adjacent the outer ends of the spray boom.

5 A spray device according to claim 4 wherein the resilient mounting comprises an arm pivoted intermediate its ends, an outer end of the arm providing a mounting for the nozzle or nozzles and a tension spring acting between an anchor point on an inner end of the arm and a further anchor point on the spray boom.

6 A spray device according to claims 4 or 5 wherein the nozzle or nozzles are located within the confines of a guard device.

7 A spray device according to any one of the above claims wherein the further tank is provided with an electrically driven pump connected to a control switch.

8 A spray device according to any or all of the above claims wherein the further tank is provided with an electrically driven agitator device adapted to agitate or stir the chemical solution in the tank.

9 A spray device according to claims 7 or 8 which includes a switching system incorporating means for actuating a visual or aural device.

10 A spray device according to claim 9 wherein the switching system is mounted on a magnetic base.

11 A spray device according to any of the above claims wherein one or more of the further nozzles is or are connected to a hand lance.

12 A method of providing or treating a sterile strip around an area for growing crops wherein a tractor-driven spray boom is traversed around the area and a herbicide liquid is sprayed from one or more nozzles located at one or both extremities of the spray boom to treat the sterile strip area.

13 A method according to claim 12 wherein the sterile strip area is sprayed with the herbicide at the same time as the crop growing area is being sprayed with a liquid crop spray.

14 A spray device as herein described with reference to the accompanying drawings.

15 A method of providing or treating a sterile strip around an area for growing crops as herein described with reference to the accompanying drawings.