Direct injection spraying assembly comprising direct dosing interface

Abstract

To provide a direct injection spraying assembly for directly injecting an active substance into a continuous water jet upstream of the spray nozzle.SOLUTION: A spraying assembly comprises: an injection device; a first hydraulic circuit (21) for conveying carrier liquid to a spray nozzle (3), the first hydraulic circuit comprising, an upstream of the spray nozzle (3), an injection section (2); a second hydraulic circuit (22) for conveying an active substance to the injection device, under an injection pressure greater than a carrier liquid circulation pressure. The injection device comprises: a direct dosing interface (1) comprising a plurality of through-holes in the injection section (2) of the first hydraulic circuit (21). The injection device further comprises at least one corresponding actuator (4) configured to open or close each through-hole so as to allow a determined dosing of the active substance to pass through at least one open hole to be injected into the carrier liquid stream.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to agricultural spraying, and specifically to a direct injection spray assembly. More specifically, the spray assembly according to the present invention comprises an active substance direct administration interface upstream of at least one spray nozzle.

Background Art

[0002] A well-known problem in the field of agricultural spraying relates to the administration of active substances to be sprayed, which must be adapted to suit needs. Optimum matching between crop protection needs and the amount of active ingredients to be sprayed is continuously sought. For this purpose, direct injection techniques have been developed.

[0003] Direct injection comprises injecting the active substance directly into a continuous stream of water upstream of the spray nozzle.

[0004] Document FR 2964047 A1 describes one example of a direct injection spray assembly. In this document, the presence of an injector immediately upstream of the spray nozzle of the spray assembly is particularly described. Each injector can be sealed by a valve to avoid over-dosing or under-dosing. From this document, the principle of actively adjusting the flow rate of active substance at each spray nozzle is already known. Thus, direct injection spray assemblies are already known which are adapted to deliver, via a set of nozzles, the active substance injected into a carrier liquid at a variable flow rate that is adjusted directly at the spray nozzle.

[0005] In known methods, in known spray assemblies of this type, the injector is configured to inject the active substance into the carrier liquid flow at the desired flow rate. The injector includes an opening that can be opened and closed by an actuator such as a solenoid valve. The injector is arranged immediately upstream of the spray nozzle.

[0006] In existing technologies relating to direct injection spray assemblies, the flow rate of the active substance injected into the carrier liquid flow is regulated directly upstream of the spray nozzle. By controlling the flow rate of the active substance to be injected through a suitable injector control, the prevention of over- or under-dosing can be improved.

[0007] However, it is not possible to precisely, directly, and continuously control the administration of the active substance injected into the carrier fluid stream.

[0008] Therefore, it is necessary to accurately and continuously administer the active substance to the spray assembly via a direct injection type spray assembly carrier liquid stream.

[0009] Needless to say, the spray assembly requires further administration of a wide range of active substances to the carrier liquid stream.

[0010] To satisfy at least part of this need, the present invention provides the use of a direct dosing interface in a direct injection spray assembly that includes a plurality of holes, specifically nanoholes and / or microholes of different sizes, which are coupled to actuators controlled for opening and closing. In this way, precise and continuous dosing of one or more active substances into a carrier fluid stream is achieved.

[0011] The distributed active substance is injected into the carrier liquid stream directly upstream of the spray nozzle. [Overview of the project]

[0012] More specifically, one object of the present invention is a spray assembly comprising a first tank configured to contain a carrier liquid, for example, water; a second tank configured to contain an active substance; at least one spray nozzle; at least one injection device; a first hydraulic circuit that transports the carrier liquid from the first tank to the spray nozzle at a carrier liquid circulation pressure, including the upstream of the spray nozzle and an injection section; and a second hydraulic circuit that transports the active substance from the second tank to the spray nozzle at an injection pressure higher than the carrier liquid circulation pressure, wherein the active substance injection device is connected to the injection section of the first hydraulic circuit and configured to inject the active substance into the carrier liquid flow circulating in the first hydraulic circuit, the injection device includes a direct dosing interface at the end of the second hydraulic circuit opposite to the second tank, including a plurality of through holes leading to the injection section of the first hydraulic circuit, and the injection device Should be injected into the carrier fluid flow The determined dose of the active substance 、 The direct dosing interface includes at least one actuator corresponding to a plurality of through-holes, configured to open and close the plurality of through-holes, thereby enabling passage through at least one open through-hole among a plurality of through-holes, and thus forming a mixture containing a carrier liquid and a distributed active substance to be sprayed from at least one spray nozzle for the purpose of crop treatment.

[0013] The present invention makes it possible to benefit from a wide dosing range of the active substance in the carrier liquid directly upstream of the nozzle of the spray system. Furthermore, the present invention makes it possible to ensure a constant dosing rate regardless of the speed of movement of the spray system or the speed of movement of the nozzle relative to the ground.

[0014] For example, at least one actuator is a piezoelectric actuator.

[0015] For example, at least one actuator is a pneumatic actuator, and the spraying system includes a compressed air circuit that enables the operation of the pneumatic actuator.

[0016] At least one of the actuators is, in particular, a piezoelectric pneumatic actuator.

[0017] For example, at least one actuator is a solenoid valve.

[0018] It is preferable that at least one actuator be controlled to open or close by a pulse width modulation generator.

[0019] The injection pressure should preferably be at least 1 bar higher than the carrier fluid circulation pressure.

[0020] In practical applications, the difference between the injection pressure and the circulation pressure depends, in particular, on the viscosity of the active substance relative to the viscosity of the carrier fluid.

[0021] Specifically, not all pores have the same diameter; the pores have different diameters, particularly between 50 μm and 300 μm.

[0022] According to one embodiment, the spray assembly includes a plurality of holes and a corresponding set of actuators, and further includes a computing unit for determining the amount of active substance to be injected into the carrier fluid stream from a dosing setpoint, and for controlling the opening and closing of a corresponding number of holes in the direct dosing interface.

[0023] According to one embodiment, a calculation unit determines the frequency of opening and closing of each hole in a set of holes of the direct dosing interface based on the carrier fluid flow rate in the first hydraulic circuit. The opening and closing frequency varies by hole, in particular, for more precise dosing at the nozzle.

[0024] According to one embodiment, the active substance circulates along the injection direction, and when the active substance is injected into the carrier liquid, the carrier liquid flows along the direction of circulation, and the injection direction of the active substance is substantially parallel to the direction of circulation of the carrier liquid, or forms an angle between 0° and 90° with it.

[0025] Advantageously, the at least one spray nozzle comprises a nozzle head defining a chamber immediately upstream of an outlet of the spray nozzle, the injection section defines an annular portion received in the chamber, and the spray assembly comprises a plurality of star-distributed holes in the injection section for injecting active substance into the nozzle head.

[0026] In this case, mixing of the active substance into the carrier liquid is better and takes place directly at the nozzle head.

[0027] Advantageously, the spray assembly comprises a plurality of spray nozzles and one or more dosing interfaces dedicated to the or the plurality of spray nozzles.

[0028] According to one embodiment, the spray assembly comprises an active substance recirculation line extending between at least one spray nozzle and a second tank to ensure continuous circulation of the active substance in the spray assembly.

[0029] Advantageously, the spray assembly comprises at least two second active substance tanks each respectively connected to a corresponding second hydraulic circuit having a direct dosing interface with a first hydraulic circuit. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] The invention will be better understood upon reading the following description, given purely by way of example, and with reference to the accompanying drawings, which are provided as non-limiting examples, in which like elements are provided with the same reference numerals. It should be noted that the drawings disclose the invention in detail for the purpose of implementing the invention, and where applicable, the drawings can of course be used to define the invention more preferably.

[0031] [Figure 1] Fig. 1 is a schematic diagram representing a spray assembly according to a first embodiment of the present invention. [Figure 2] Fig. 2 is a schematic diagram representing a spray assembly according to a second embodiment of the present invention. DESCRIPTION OF EMBODIMENTS

[0032] The present invention relates to a direct injection type spray assembly. Such a spray assembly is schematically shown in Figure 1, and another embodiment is shown in Figure 2.

[0033] The spray assembly includes a first tank for containing a carrier liquid, which is particularly water, and a second tank for dispensing an active substance, which is particularly a herbicide, fungicide, insecticide, or fertilizer. According to one embodiment, the spray assembly includes several second tanks containing different active substances. In this case, the different active substances are distributed simultaneously into the carrier liquid.

[0034] The spray assembly according to the present invention further includes at least one spray nozzle 3, and it is preferable that the multiple spray nozzles 3 are distributed along a spray inclined section. For example, the spray inclined section is arranged in multiple sections, each containing a set of spray nozzles 3 configured to be controlled identically.

[0035] Each of the first and second tanks is connected to a spray nozzle via a first hydraulic circuit 21 and a second hydraulic circuit 22, respectively. In particular, if there are several second tanks containing multiple active substances, there are several second hydraulic circuits 22, each having an interface with the first hydraulic circuit 21.

[0036] The first hydraulic circuit 21 and the second hydraulic circuit 22 are closed circuits connected by a recirculation pipeline, and it is preferable that the first hydraulic circuit 21 loops back to the first tank and the second hydraulic circuit 22 loops back to the second tank.

[0037] Specifically, the spray assembly includes an injection device located directly upstream of the spray nozzle 3, connected between the second hydraulic circuit 22 and the injection section 2 which forms part of the first hydraulic circuit 21.

[0038] The injection device is configured to inject the active substance into a carrier fluid flow circulating in the first hydraulic circuit 21 from the first tank to the spray nozzle 3. For this purpose, the injection device includes a direct dosing interface 1 having one or more holes, which allows the active substance to be injected into a carrier fluid flow circulating in the injection section 2 of the first hydraulic circuit 21.

[0039] The active substance circulates in the second hydraulic circuit 22 at the injection pressure, and the carrier liquid circulates in the first hydraulic circuit 21 at a circulation pressure lower than the injection pressure. The injection pressure is preferably at least 1 bar higher than the circulation pressure. For example, the injection pressure is 6 bar and the circulation pressure is 3 bar. In practice, the injection pressure is selected according to the physicochemical properties of the components, specifically their viscosity.

[0040] According to the embodiment shown in Figure 1, the direction of circulation of the active substance in the direct administration interface 1 is substantially perpendicular to the direction of circulation of the carrier solution. In this case, for the most effective mixing, it is preferable that the pressure difference between the injection pressure and the circulation pressure be large, and in particular, greater than 2 bar and greater than 3 bar.

[0041] According to the embodiment shown in Figure 2, the direction of circulation of the active substance in the direct administration interface 1 is substantially parallel to the direction of circulation of the carrier fluid. In this case, the pressure difference between the injection pressure and the circulation pressure can be small, particularly within the range of 1 bar.

[0042] Therefore, in the direct administration interface, the angle formed between the main axis along which the active substance circulates and the main axis along which the carrier fluid circulates may be specifically between 0° and 90°. The closer the angle is to 0°, that is, the more substantially parallel the direction of circulation of the active substance in the direct administration interface is to the direction of circulation of the carrier fluid, the easier it is to inject the active substance into the carrier fluid.

[0043] The pores of the direct administration interface 1 are, in particular, substantially annular and having a diameter between 50 μm and 300 μm. According to one embodiment, if several pores are present, they may have different diameters.

[0044] Each hole is coupled to an actuator 4 that controls the opening and closing of the flow path for an active substance through the hole. Preferably, the actuator 4 is coupled to a single hole. Alternatively, the actuator 4 may be coupled to a group of holes, opening and closing all holes in the group simultaneously. Specifically, each actuator opens and closes each hole with a single opening and closing frequency, and the opening and closing is controlled by a pulse width modulation (PWM) generator.

[0045] According to one embodiment, the control unit 10 is configured to command the opening and closing of a number of holes corresponding to a dose setpoint. Thus, based on the desired active substance dose corresponding to the dose setpoint determined by a calculation unit configured for this purpose, for example, the control unit 10 determines the number of holes to be opened, the other holes to be closed, and the frequency of opening and closing each hole in order to inject a desired amount of active substance into the carrier solution.

[0046] In particular, the dose setting point may depend on various parameters that may be changed individually or simultaneously, including the speed of the spraying system, especially the speed of the spray nozzle. The dose setting point can be determined based on mapping the adjustment of the dose of the active substance to be applied, or based on calculations based on the recognition of the crop to be treated.

[0047] In addition, based on the flow rate of the active substance required in the second hydraulic circuit 22 and the flow rate of the carrier fluid circulating in the first hydraulic circuit 21, the calculation unit 10 can determine a set of control signals to alternately open and close a set of holes in the direct dosing interface, where the opening time and closing time are variables of each spray nozzle 3.

[0048] For example, the control unit 10 determines a set of holes and the frequency of alternating opening and closing of the holes in that set. This injects a desired amount of the active substance into the carrier liquid flow directly upstream of the spray nozzle 3.

[0049] Therefore, as an example, according to the present invention, the calculation unit 10 determines the amount of active substance to be sprayed in L / min, which corresponds to the desired flow rate of the active substance at the outlet of the spray nozzle 3. The desired flow rate of the active substance at the nozzle outlet corresponds to the dose setting point.

[0050] Depending on the flow rate of the carrier liquid sent to the spray nozzle 3, and, for example, the speed of the spray assembly, the control unit 10 determines the amount of active substance to be injected into the carrier liquid in the injection section 2 over time.

[0051] For example, the control unit determines the number of holes to be opened, and / or the frequency of opening and closing of a set of holes in the direct administration interface 1, and the duration of hole opening, based on the amount of active substance to be injected over time. The control unit 10 then generates a corresponding control signal and transmits it to the actuator.

[0052] According to one embodiment, the direct administration interface is substantially annular and includes at least one pore, such as 32 pores, having at least two different diameters from among the diameters of 50 μm, 80 μm, 100 μm, 150 μm, 180 μm, 200 μm, and 300 μm.

[0053] One advantage of having pores of different sizes is the potential for a wider dosage range.

[0054] According to one particular embodiment, the spray nozzle 3 of the spray assembly includes a nozzle head that forms a chamber directly upstream of the spray nozzle 3, and the injection section 2 forms an annular portion housed in the chamber. to To inject the active substance, the pores are distributed in a star shape in the injection section.

[0055] Actuator 4 is, for example, a piezoelectric actuator. Alternatively, actuator 4 may be a pneumatic valve control actuator. In this case, the spray assembly further includes a compressed air circuit to ensure the opening and closing of the pneumatic valve.

[0056] One advantage of pneumatic valves is that they close using the force of compressed air. This eliminates the need to provide the mechanical force required for, for example, spring-driven closing systems, which would increase the overall size.

[0057] In another embodiment, the actuator 4 is a solenoid valve. One advantage of using a solenoid valve is that it is easy to drive. The solenoid valve is driven directly and does not require the air circuit to be actuated in advance, as is the case with pneumatic valves.

Claims

1. A first tank configured to contain a carrier liquid, A second tank configured to contain the active substance, At least one spray nozzle (3) and At least one injection device, A first hydraulic circuit (21) for transporting carrier liquid from the first tank to the spray nozzle (3) at a carrier liquid circulation pressure, the first hydraulic circuit (21) includes the upstream of the spray nozzle (3) and an injection section (2), A second hydraulic circuit (22) for transporting the active substance from the second tank to the injection device at an injection pressure greater than the carrier fluid circulation pressure, Includes, The injection device is connected to the injection section (2) of the first hydraulic circuit (21) and is configured to inject an active substance into the carrier fluid flow circulating in the first hydraulic circuit (21). The injection device includes a direct dosing interface (1) at the end of the second hydraulic circuit (22) opposite to the second tank, which includes a plurality of through holes leading to the injection section (2) of the first hydraulic circuit (21), The injection device includes at least one actuator (4) corresponding to the plurality of through holes, configured to open and close the plurality of through holes, so as to allow a determined dose of the active substance to be injected into the carrier liquid flow to pass through at least one open through hole of the plurality of through holes of the direct administration interface (1), and so as to form a mixture comprising the carrier liquid and the distributed active substance to be sprayed from at least one spray nozzle (3) for the purpose of treating crops. Spray assembly.

2. The at least one actuator (4) is a piezoelectric actuator. The spray assembly according to claim 1.

3. The at least one actuator (4) is a pneumatic actuator, Includes a compressed air circuit that enables the operation of the aforementioned pneumatic actuator, The spray assembly according to claim 1.

4. The at least one actuator (4) is a piezoelectric pneumatic actuator. The spray assembly according to claim 3.

5. The at least one actuator (4) is a solenoid valve. The spray assembly according to claim 1.

6. The opening and closing of at least one actuator (4) is controlled by a pulse width modulation generator. The spray assembly according to claim 1.

7. The injection pressure is at least 1 bar higher than the carrier fluid circulation pressure. The spray assembly according to claim 1.

8. Not all of the aforementioned through holes have the same diameter; rather, the different diameters of the holes are particularly between 50 μm and 300 μm. The spray assembly according to claim 1.

9. A set of actuators corresponding to the plurality of through holes, Includes, A calculation unit (10) for determining the amount of active substance to be injected into the carrier fluid stream from the administration setting point, and for controlling the opening and closing of the corresponding number of holes in the direct administration interface (1), This also includes, The spray assembly according to claim 1.

10. The calculation unit (10) determines the frequency of opening and closing each hole in the set of holes of the direct administration interface (1) based on the carrier fluid flow rate in the first hydraulic circuit. The spray assembly according to claim 9.

11. The active substance circulates along the injection direction, and when the active substance is injected into the carrier liquid, the carrier liquid flows along the direction of circulation, and the injection direction of the active substance is substantially parallel to the direction of circulation of the carrier liquid, or forms an angle between 0° and 90° with the direction of circulation. The spray assembly according to claim 1.

12. The at least one spray nozzle (3) includes a nozzle head that forms a chamber directly upstream of the outlet of the spray nozzle (3), The injection section (2) forms an annular portion housed in the chamber, To inject the active substance into the nozzle head, the injection section (2) has a plurality of holes distributed in a star shape, including, The spray assembly according to claim 1.

13. Multiple spray nozzles (3) and One or more administration interfaces dedicated to one spray nozzle (3) or multiple spray nozzles (3), including, The spray assembly according to claim 1.

14. In order to ensure the continuous circulation of the active substance through the spray assembly, an active substance recirculation pipeline is provided extending between the at least one spray nozzle (3) and the second tank, including, The spray assembly according to claim 1.

15. At least two second active substance tanks, each connected to a corresponding second hydraulic circuit (22) having the direct administration interface (1) with the first hydraulic circuit (21), including, The spray assembly according to claim 1.

Images