GB2116013A - Method and apparatus for marking ground - Google Patents

Abstract

The extent of land treated by an agricultural operation, e.g. spraying, is indicated by placing blobs or strips of foam on the ground at the edge of the treated strip. The foam is generated from a canister (4), e.g. an aerosol can, which may be fixed in a suitable holder and actuated e.g. by a solenoid operated actuation arm (12). The size or length of foam blob and the spacing between them may be varied. The foam is preferably long lasting and somewhat weather resistant. <IMAGE>

Description

SPECIFICATION Method and apparatus for marking ground This invention relates to methods and apparatus for marking ground. It is of particular value in marking ground which has been treated by an agricultural operation, e.g. spraying, in order to enable ground to be treated overall by an operative but nowhere twice and without any portions being left untreated.

Such methods and apparatus are known and are described inter alia in British Patent Specification No.

1,163,201. That specification describes and claims methods and apparatus for indicating the lateral boundary of a bout treated by an agricultural vehicle, wherein a supply of foamable material is provided on the vehicle and discharged therefrom in at least one line parallel to the direction of motion of the vehicle. Discharge takes place, for example, intermittently to leave a line of foam blobs and this line may conveniently be situated at the edge of a strip of land over which a spray bar has been passed.

Such apparatus has been manufactured and used commercially but it suffers a number of disadvantages.

In particular, the apparatus is cumbersome and expensive and the pipework through which foam is passed requires maintenance and is subject to blockage.

Additionally, the method of foam generation described in the specification referred to, which consists of bubbling the exhaust gas from the agricultural vehicle through a liquid including a surface active agent to generate a foam is not particularly long lasting or weather resistant and often disappears too rapidly for practical use. Particularly if a large size field is being treated, the mark laid down at one end of the field may have disappeared by the time the tractor returns to that same end.

According to a first feature of the present invention there is provided a method of marking land treated by an agricultural operation which comprises mounting on a vehicle a foam generating canister, providing means for intermittently generating foam from the canister and causing or allowing the foam to impinge on the ground, the foam generation being by means of propellant and foam generating components contained in the canister and discharged through a valve and the actuation of the canister being effected at predetermined times by an electromechanical actuation system.

Conveniently means are provided to vary the timing of the actuation, both in terms of the period of actuation each time actuation occurs and in respect of the period between actuations.

The mixture of propellant and foam forming components may conveniently be packaged in a standard aerosol can and the components are preferably chosen to give a visible foam, conveniently white in colour, with adquate persitance and, in particular adequate rain or moisture resistance.

Conveniently, and preferably, two actuator devices are located one on each end of a spraying bar or analogous piece of equipment, the actuators being so arranged that when equipped with canisters the canister discharges the foam to lie on the ground substantially at the edge of the treated strip. Switch means are preferably provided in order to actuate one or other of the actuation devices as desired. Most conveniently, a control box is provided in a tractor cab having three controls, first a three-position swtich having positions corresponding to left-hand actuator operative, off, and right-hand actuator operative, a control to vary the length of the actuation (and therefore the size of the foam blob or strip deposited) and a second control to vary the frequency with which actuations occur (and accordingly the spacing between adjacent blobs or strips of foam on the ground).

Such apparatus has substantial advantages compared with that described in the specification referred to above. In particular, the electrical system may be simply and easily produced using modern electronics which by viture of their solid state nature gives high reliability. The wiring may be straightforward to combined solenoid actuator/aerosol can support members one on each end of a spray boom, and aerosol cans can be produced inexpensively and in quantity. Aerosol cans are in general reliable, and require no maintenance since once used they are simply disposed of. Accordingly, all that a farmer or the like has to do to operate the system of the present invention when spraying is to attach an aerosol canister to the end of a spray bar, switch a switch in the cab and set two controls depending upon the terrain he is treating and the speed at which he is proceeding over it.

The invention is illustrated by way of example with reference to the accompanying drawings in which Figure 1 shows a general arrangement of a tractor and spray bar showing diagrammatically the main components of apparatus according to the invention; Figure2 is a diagram showing the component parts in more detail, and Figure 3 is a suitable circuit for the control box.

Referring to the drawings a tractor 1 carries mounted on its rear a spray bar 2. Treatment liquid is fed from a tank 3 via conventional means to a plurality of sprayheads located along the bar 2.

In accordance with the invention an aerosol canister 4 is mounted in a suitable combined solenoid actuator and holder at each end of spray bar 2. A wire leads from the solenoid to a control box 5 counted in the cab of the tractor.

Referring now to Figure 2, the apparatus of the invention is shown in more detail. The control box 5 is connected by means of an electrical lead 6 to the 12 volt power supply of the tractor. The control box has three controls mounted on it, viz. a switch 7, size control 8 and spacing control 9. Switch 7 has three positions, a central off position, and two positions corresponding to actuation of the solenoid on the left-hand end of the sprayer bar and actuation of the solenoid on the right-hand end of the sprayer bar.

Size control 8 varies the length of time for which the solenoid is actuated each time, while spacing control 9 varies the frequency of actuation of the solenoid and thus, as the tractor is continuously moving along, the spacing between adjacent blobs of foam.

Each solenoid/mounting unitforthe aerosol canister4consists of a body 10 having extending therefrom a bracket clip 11 which serves to hold the canister firmly in the position shown. Also extending from housing 10 is an actuation arm 12 which is suitably shaped and sized to engage a dispensing nozzle 13 on the aerosol container. When dispensing nozzle 13 is moved towards the body of the aerosol container 4, foam is ejected in the direction of the arrow.

Although in the circuit shown a single wire connection to each solenoid is used, the circuit being completed by return through the metal of the sprayer bar itself, it is of course possible to operate on a two-wire system if desired. A suitable simple plug and socket connection may be provided centrally of the sprayer bar to enable the sprayer bar to be removed from the tractor leaving the control box in position.

By mounting the aerosol cans 4 as shown they may be of very simple construction and in particular no dip tube is necessary since the contents automatically drop to the lowest point, i.e. adjacent valve 13.

The filling of the aerosol can vary very widely. By way of example a typical canister has a capacity of one litre and maybe e.g. type 1000.065 ex Metal Box having external dimensions of diameter 65 mm length 300 mm. The filling may be any appropriate foam filling of which the following is an example: Example The following ingredients were used to form a filling:: Parts by weight Polymer beads (Pristerine 4901 ex Unichema International Ltd.) 8 Crodacid PC 3140F ex Croda Chemicals Ltd. 4 Propellant (Arcton 12/114 40/60 ex ICI) 10 Sorbo 201 (ex Honeywell-Atlas Limited) 10 Demineralised water 60.8 Triethanolamine 7.2 The filling was formulated by heating the last three ingredients together to a temperature of 70"C and then adding the first three ingredients with stirring and continuing stirring until the mixture had cooled to room temperature whereafter it was filled into aerosol containers. The foam produced from such containers is of dense structure, and resistant to moisture and rain. The foam is coloured a brilliant white.

Figure 3 shows the circuit diagram for control box 5. Power fed in via leads 6 is applied by switch 7ato power up the electronic circuit shown. This consists basically of a multivibrator circuit 20 the output of which is processed via a simple two transistor circuit 21 the output transistor of which drives the coil of a relay 22.

Variable resistors 8 and 9 forming part of the multivibrator circuit 20 can be used to vary the one and off times at the output of the circuit 20 which is fed to circuit 21. This varies the switching on and off of the TIP 3055 output transistor and accordingly the energisation of relay 22. The normally open contact of relay 22 is connected to the positive supply line and to switch 7b, which switch determines which of the two solenoids in housings 10 is actuated.

CLAIMS (Filed 3/2/83) 1. A method of marking land treated by an agricultural operation which comprises mounting on a vehicle a foam generating canister, providing means for intermittently generating foam from the canister and causing or allowing the foam to impinge on the ground, the foam generation being by means of propellant and foam generating components contained in the canister and discharged through a valve, and the actuation of the canister being effected at predetermined times by an electromechanical actuation system.

2. A method according to claim 1 substantially as hereinbefore described with reference to the accompanying drawings.

3. Apparatus for marking land treated by an agricultural operation which comprises a foam generating canister, means for mounting the foam generating canister on a vehicle, means for intermittently generating foam from the canister to cause or allow the foam to impinge upon the ground, the canister including

**WARNING** end of DESC field may overlap start of CLMS **.

Claims (9)

1. **WARNING** start of CLMS field may overlap end of DESC **.

   Size control 8 varies the length of time for which the solenoid is actuated each time, while spacing control 9 varies the frequency of actuation of the solenoid and thus, as the tractor is continuously moving along, the spacing between adjacent blobs of foam.

   Each solenoid/mounting unitforthe aerosol canister4consists of a body 10 having extending therefrom a bracket clip 11 which serves to hold the canister firmly in the position shown. Also extending from housing 10 is an actuation arm 12 which is suitably shaped and sized to engage a dispensing nozzle 13 on the aerosol container. When dispensing nozzle 13 is moved towards the body of the aerosol container 4, foam is ejected in the direction of the arrow.

   Although in the circuit shown a single wire connection to each solenoid is used, the circuit being completed by return through the metal of the sprayer bar itself, it is of course possible to operate on a two-wire system if desired. A suitable simple plug and socket connection may be provided centrally of the sprayer bar to enable the sprayer bar to be removed from the tractor leaving the control box in position.

   By mounting the aerosol cans 4 as shown they may be of very simple construction and in particular no dip tube is necessary since the contents automatically drop to the lowest point, i.e. adjacent valve 13.

   The filling of the aerosol can vary very widely. By way of example a typical canister has a capacity of one litre and maybe e.g. type 1000.065 ex Metal Box having external dimensions of diameter 65 mm length 300 mm. The filling may be any appropriate foam filling of which the following is an example: Example The following ingredients were used to form a filling:: Parts by weight Polymer beads (Pristerine

   4901 ex Unichema International Ltd.) 8 Crodacid PC 3140F ex Croda Chemicals Ltd. 4 Propellant (Arcton 12/114 40/60 ex ICI) 10 Sorbo 201 (ex Honeywell-Atlas Limited) 10 Demineralised water 60.8 Triethanolamine 7.2 The filling was formulated by heating the last three ingredients together to a temperature of 70"C and then adding the first three ingredients with stirring and continuing stirring until the mixture had cooled to room temperature whereafter it was filled into aerosol containers. The foam produced from such containers is of dense structure, and resistant to moisture and rain. The foam is coloured a brilliant white.

   Figure 3 shows the circuit diagram for control box 5. Power fed in via leads 6 is applied by switch 7ato power up the electronic circuit shown. This consists basically of a multivibrator circuit 20 the output of which is processed via a simple two transistor circuit 21 the output transistor of which drives the coil of a relay 22.

   Variable resistors 8 and 9 forming part of the multivibrator circuit 20 can be used to vary the one and off times at the output of the circuit 20 which is fed to circuit 21. This varies the switching on and off of the TIP 3055 output transistor and accordingly the energisation of relay 22. The normally open contact of relay 22 is connected to the positive supply line and to switch 7b, which switch determines which of the two solenoids in housings 10 is actuated.

   CLAIMS (Filed 3/2/83) 1. A method of marking land treated by an agricultural operation which comprises mounting on a vehicle a foam generating canister, providing means for intermittently generating foam from the canister and causing or allowing the foam to impinge on the ground, the foam generation being by means of propellant and foam generating components contained in the canister and discharged through a valve, and the actuation of the canister being effected at predetermined times by an electromechanical actuation system.
2. 2. A method according to claim 1 substantially as hereinbefore described with reference to the accompanying drawings.
3. 3. Apparatus for marking land treated by an agricultural operation which comprises a foam generating canister, means for mounting the foam generating canister on a vehicle, means for intermittently generating foam from the canister to cause or allow the foam to impinge upon the ground, the canister including

   propellant and foam generating components and a valve through which the components may be discharged, and the apparatus including an electromechanical actuation system arranged to actuate the canister valve at predetermined times.
4. 4. Apparatus according to claim 3 and including means to vary the timing of the actuation both in terms of the period of actuation each time actuation occurs and in respect of the period between actuations.
5. 5. Apparatus according to claim 3 or 4 wherein the mixture of propellant and foam-forming components is packaged in a standard aerosol can and arranged to give a white foam.
6. 6. Apparatus according to any of claims 3 to 5 and including two foam generating canisters and wherein the means for mounting the canisters on a vehicle consists of a spray bar adapted for mounting on a tractor.
7. 7. Apparatus according to claim 6 and including switch means enabling selective actuation of one or other of the actuation devices associated with the two canisters.
8. 8. Apparatus according to claim 6 or 7 and including a control box adapted for mounting in a tractor cab having three controls, a three-position switch having positions corresponding to left-hand actuator operative, off and right-hand actuator operative, second, a control to vary the length of the actuation and third, a control to vary the frequency with which actuations occur.
9. 9. Apparatus for marking land treated by an agricultural operation and substantially as hereinbefore described with reference to the accompanying drawings.