GB2048091A - Spraying Equipment - Google Patents

Abstract

Diluent is supplied to a spray boom 7 from a source 1 through a line 3 whilst concentrate is supplied from a source 6 through a line 2' in response to the flow through a second line 2 from the source 1. A controller 8 controls the flow rates in the lines 2 and 3. <IMAGE>

Description

SPECIFICATION Spraying Equipment Technical Field of the Invention The present invention relates to spraying equipment and particularly to spraying equipment for agricultural purposes.

In present day systems spray chemicals are mixed with a large amount of water, for example, 5 litres of concentrate to 2000 litres of water, and the mixture is then sprayed through nozzles of a spraying boom to a field containing crops for example. During this time the mixture is continuously stirred to maintain consistency.

Control of application with regard to correct proportions of concentrate and diluent is effected in a rudimentary fashion and consequently it will be appreciated that such spraying systems are inefficient and lack refinement of operation.

Disclosure of the Invention It is an object of the present invention to provide spraying equipment, particularly for agricultural purposes, which is safer, more convenient to use, and which will ensure that the recommended proportions of concentrate and diluent are present in any given mixture to be sprayed.

According to the invention there is provided spraying equipment comprising a spraying boom, diluent dispensing means, a first line for conveying diluent coupled between said dispensing means and said boom, a second line for conveying diluent from said source, concentrate-dispensing means operable tp dispense concentrate in response to flow in said second line, to mix with diluent in said first line entering said boom, and control means for controlling the mix of diluent and concentrate delivered to said boom during a spraying operation.

Brief Description of Drawings Embodiments of the invention will now be described by way of example with reference to the sole accompanying drawing which depicts spraying equipment according to the invention.

Best Modes of Carrying Out the Invention The spraying system shown in the drawing has a diluent-providing source 1 provided with a pump (not shown) for pumping the diluent along lines 2 and 3 through flow metering devices 4 and 5 respectively.

The flow metering device 5 is coupled to a spraying boom 7 and to a master controller 8, whereas the flow metering device 4 is coupled to the master controller 8 and also to a concentrate dispensing device 6.

In the preferred embodiment the concentrate.

dispensing device 6 is a pressure vessel into which is placed a container containing concentrate to be mixed with diluent flowing in line 3.

The concentrate dispensing device 6 is connected to the line 3 by line 2' downstream of the flow metering device 5, before the line 3 enters the boom 7.

The master control 8 is also connected to a valve 9 in the line 3 upstream of the flow metering device 5, and to a valve 10 in the line 2 upstream of the flow metering device 4. A conflection 13 is also made between the boom 7 and the master control 8, to register a signal representative of the speed of the equipment over ground. The master control 8 includes a card reader 11 for feeding information to the controller 8 representative of the recommended litres per hectare of chemical concentrate and litres per hectare of diluent to be mixed for spraying through the boom 7 according to the requirement of a crop to be chemically sprayed.

A feedback line 12 is also provided to feed the diluent delivered to the concentrate dispensing device back to the diluent providing source 1.

In operation the collapsible bag containing the concentrate is placed in the pressure vessel 6 and the diluent dispensing source 1 is filled with diluent, normally water. Diluent is then pumped along lines 2 and 3 and through flow metering devices 4 and 5 respectively, the diluent in line 3 going directly to the boom 7. The metering devices 4 and 5 measure the flowrate of diluent in the respective lines which are in turn fed to the controller 8. The diluent in line 2 is delivered, after passing metering device 4, to the pressure vessel 6 and concentrate is displaced from the container therein in proportion to the flowrate of diluent.

The concentrate displaced is fed through line 2' to mix with the diluent entering the boom 7. A typical application rate is 250 litres per hectare of diluent containing 5 litres per hectare of concentrate and the system can ensure correct mixing of these rates prior to entry to the boom 7.

The master controller 8 continuously records or ingests the flowrate of diluent through the metering devices 4 and 5, for comparison with a factor representative of the multiplicand of the speed of movement of the equipment and the width of the boom as to be described shortly. The concentrate containing bag has a tag attached thereto for use in the card reader 1 The tag or card is coded in relation to the litres per hectare of concentrate required and the litres per hectare of diluent required to be mixed therewith to provide the correct mixtre of spray to be sprayed from the boom 7. These values are fed in and stored in the master controller 8.

The master controller 8, as already mentioned, is adapted to monitor and store the flowrate along lines 2 and 3 measured by the flow metering devices 4 and 5 and also a factor representative of the multiplicand of the speed of the equipment over the ground and the width of the boom 7.

The flowrate through each of the flow metering devices 4 and 5 can be compared in the master controller 8 with the multiplicand of the speed of the spraying equipment and the width of the boom which latter integer is a known factor which can be fed into the controller 8 at the start of a spraying operation. Such a comparison is proportional to the volume of diluent flowing per hectare of ground and therefore can be compared with the correect corresponding values fed into the master controller by the card reader 11.

If the results of these final comparisons depart from unity then the valves 9 and 10 in the lines 3 and 2 can be controlled by the master controller 8 to readjust the respective flowrates to ensure that the required spray rate is being delivered from the boom 7 in accordance with a given controlled speed of the spraying equipment over the ground.

It will of course be appreciated that alternatively the speed of the vehicle could be adjusted so that the required spray rate continues to be delivered from the boom 7. The speed of the equipment over the ground can be obtained from s. vernal known methods. Normally the trailing wheel of the sprayer i.e. non-powered, has a distance of pick-off and this can be fed into the master controller 8.

The vehicle's speed, however, could be obtained from a Doppler radar system looking at the ground. Alternatively the device might obtain its speed from measurement of the actual crop being sprayed, that is the device could be designed to sense each emerging shoot and apply the right quantity of spray proportionally to the repetition rate of the shoot emergence or it might recognise the crop density of wheat for example by optical methods or by chemical or electrical methods whereby part of the portion of the crop immediately in front of the wheels carrying the spraying equipment is fed into a detector which works out the density of the crop or shortage of an element by some system of flume photometer and apportions the spray in an appropriate manner.This arrangement should enable an approach to spraying by looking at the application of the chemical to the plant rather than litres per hecta re.

The card reader 11 may be photoelectric, magnetic or switch operated by any of the known systems. The card is attached to the container containing the concentrate and remains attached to the container so that only by use of the card can the chemical be dispensed.

Further variations of the system as described could include the incorporation of an anemometer to measure wind speed and a thermometer to measure temperature to thus ensure that the correct and recommended manufacturer's operating additions are adhered to.

The system is applicable to control droplet application or conventional spraying and it would be possible for one chemical to be used at two rates for different spraying systems. This data could be incoded on the card for use in the card reader.

Additionally, the coding system could be adapted to include a desired nozzle pressure. This in turn would dictate the droplet size of the spray which may vary from crop to crop. This does not necessarily apply to control droplet application where it is rather difficult to change the droplet size. If the setting up of the spraying equipment (different chemicals require different application rates and quite often different nozzles) was incorrect, i.e. correct flow rates and pressure do not occur at a predetermined speed, the instrument could be adapted to light a fault lamp to indicate this error.

In a similar way the chemical manufacturer could produce a coded card having various coefficients entered thereon. It would also be possible to have a third card entered into the card reader which was related to the crop where the different tracks on the card could be read according to the stage at which the crop had attained a certain growth, that is pre-emergent spraying could be automatically actuated at the correct rates.

The advantage of the system above described over present known methods will be evident to those skilled in the art. Amongst the advantages it will be noted that since the pump of the system sees no chemicals it can be of cheaper design.

This also applies to the flow metering devices which encounter only diluent, normally water, during operation. Further, it becomes necessary in the present system for a farmer for example, to handle the chemicals to be sprayed. This is important where the chemicals being used present a health hazard in their raw state.

Claims (10)

Claims

1. Spraying equipment comprising a spraying boom, diluent dispensing means, a first line for conveying diluent coupled between said dispensing means and said boom, a second line for conveying diluent from said source, concentrate-dispensing means operable to dispense concentrate in response to flow in said second line, to mix with diluent in said first line entering said boom, and control means for controlling the mix of diluent and concentrate delivered to said boom during a spraying operation.

2. Spraying equipment as claimed in Claim 1 wherein said control means is provided with storage means for storing information representative of boom width and a required mix of concentrate and diluent to be sprayed, monitoring means for monitoring rates of flow of diluent in said first and second lines and the speed of the boom over ground, during a spraying operation, and comparator means adaptea to compare the multiplicand of said speed and boom width with said flow rates to determine the mix of diluent and concentrate being sprayed, and the results of this comparison with said required mix stored in said storage means.

3. Spraying equipment as claimed in Claim 2 wherein said monitoring means includes a first metering device installed in said first line for monitoring the rate of flow of diluent therealong, and a second metering device installed in said second line for monitoring the rate of flow of diluent therealong, upstream of said concentratedispensing means.

4. Spraying equipment as claimed in any preceding claim including card reader means for feeding information to said storage means representative of the required mix of diluent and concentrate so that said comparison can be effected.

5. Spraying equipment as claimed in Claim 4 wherein said comparator means is adapted to adjust the flowrates of diluent and concentrate in said first and second lines to ensure delivery of said required mix to the boom.

6. Spraying equipment as claimed in Claim 4 wherein said comparator means is adapted to adjust the speed of movement of the boom to ensure delivery of said required mix to the boom.

7. Spraying equipment as claimed in Claim 4 wherein said comparator means is adapted to adjust both the speed of movement of the boom and the flow rates of diluent and concentrate to ensure delivery of said required mix to the boom.

8. Spraying equipment as claimed in any preceding claim wherein a feedback line is provided for conveying diluent delivered to the said concentrate-dispensing means, back to said diluent dispensing means.

9. Spraying equipment as claimed in any preceding claim wherein said concentratedispensing device is a pressure vessel remoyably receiving a concentrate container whereby concentrate is dispensed in proportion to flowrate of diluent along said second line.

10. Spraying equipment substantially as hereinbefore described with reference to and as illustrated in the accompanying drawing.