Method for managing a ventilation regime for a direct jet spraying system

Abstract

The present invention relates to a method for delivering a pulsed airflow (PAF) in a spraying system (10) of a product to be sprayed (8) carried by an airflow directed towards target vegetation (TV), the spraying system being mounted on board an agricultural machine (9) and comprising at least one fan (7) driven by a fan motor (4), the method iteratively comprising: - an evaluation of the forward speed (VA) of the agricultural machine relative to the ground, - a determination, as a function of the forward speed, of at least one flow control parameter related to the pulsed airflow to be delivered, - the control of the fan motor according to the flow control parameter, and a spraying system implementing such a method. Abstract figure: Figure 4

Description

Title of the invention: Method for managing a ventilation regime for a direct-jet spraying system. Technical field

[0001] The present invention relates to the field of product spraying systems used in agricultural operations, particularly vineyards or orchards. These spraying systems are used to apply products, such as plant protection products, to target vegetation, e.g., tree foliage, shrub foliage, vine foliage, etc.

[0002] Said spraying systems are generally associated with an agricultural machine, whether the spraying system is mounted or trailed. STATE OF THE ART

[0003] In this field, it is known to combine an airflow to accompany the spraying of the product; this is referred to as an "air-assisted" spraying system. Furthermore, it is known to adjust the quantity of product sprayed by the spraying system according to the forward speed of the agricultural machinery.

[0004] However, the airflow used to form the spray pattern is generated by a fan, generally controlled in an on / off mode. Consequently, if the quantity of product sprayed by the spraying system, as a function of the forward speed of the agricultural machinery, varies over time according to a non-constant forward speed, the aerodynamic conditions and the proportion of product sprayed in the airflow are not constant. This leads to variations in product projection and imperfect spray quality. In other words, dispersions occur in the delivery and application of the product, a consequence of the variable speed of the agricultural machinery passing over the treatment area, which generates variable aerodynamic conditions.

[0005] There therefore remains a need to improve the quality and repeatability of the product spraying process, in order to reduce dispersions in the delivery and application of the product on the vegetation. PRESENTATION OF THE INVENTION

[0006] In this context, the present invention relates to a method for delivering a pulsed airflow in a spraying system of a product to be sprayed, carried by an airflow directed towards target vegetation, the spraying system being mounted on board an agricultural machine and comprising at least one fan driven by a fan motor, the method iteratively comprising:

[0007] - an evaluation of the forward speed of the agricultural machine relative to the ground,

[0008] - a determination, as a function of the feed rate, of at least one parameter of flow control in relation to the pulsed airflow to be delivered,

[0009] - the control of the fan motor according to the flow control parameter.

[0010] Thanks to these arrangements, the airflow is advantageously adjusted according to the forward speed of the agricultural machinery, with a certain degree of proportionality that will be discussed in detail later. If the delivery of the product to be delivered is also based on the forward speed of the agricultural machinery, identical or very similar aerodynamic conditions can be obtained even if the forward speed changes over time, thereby also allowing the product to be delivered homogeneously and in a well-controlled quantity over the entire target vegetation, regardless of the forward speed or the agricultural machinery.

[0011] In a fairly steep uphill course with a substantial load, the agricultural machine's powertrain may reach its power limit for moving the agricultural machine, so the decrease in engine speed and advance speed is advantageously accompanied by a simultaneous decrease in fan speed, which makes it possible to recover part of the power consumed by the fan, such recovery not being conceivable in the known art.

[0012] It should be noted that the product to be sprayed may be a plant protection product, more generally a plant treatment product. In the trade, this is referred to as the "spraying mixture." It should be noted that the motor driving the fan may be a hydraulic motor or an electric motor.

[0013] As will be discussed in more detail later, the agricultural machine may or may not be a straddle tractor. Furthermore, the agricultural machine may be a tractor carrying the spraying system, or the agricultural machine equipped with the spraying system may be a unit towed by a tractor.

[0014] The target vegetation can typically be a vineyard or an orchard, without this constituting a limitation to the possible applications of the present invention.

[0015] The delivery of the product in the carrying airflow can be carried out in a downstream position, i.e. at the place where the pulsed air exits to the open air through the air nozzles, or it can be carried out in a slightly upstream position, i.e. in a pulsed air duct at a distance from the exit to the open air.

[0016] According to one embodiment, the flow control parameter is a target fan speed. The airflow is controlled in relation to the forward speed of the agricultural machine by means of the fan speed, whether it is driven by a hydraulic motor or an electric motor.

[0017] According to an alternative embodiment, the flow control parameter can be a hydraulic solenoid valve opening, for example the hydraulic solenoid valve that supplies the hydraulic motor driving the fan.

[0018] According to one embodiment, the evaluation of the forward speed of the agricultural machine is carried out by means of one and / or the other of the following means:

[0019] - a geo-positioning system, preferably a geo-positioning system Differential positioning system (DGPS), with time-dependent positioning function,

[0020] - a system based on frequency signals delivered by a sensor opposite of a toothed wheel, mechanical or magnetic, in kinematic relationship with a tractor wheel,

[0021] - a system based on a radar sensor interacting with the ground,

[0022] - an inertial platform, comprising at least one acceleration sensor longitudinal and an integration function, with periodic recalibration.

[0023] Either of the above means can be used to determine the forward speed of the agricultural machine. In circumstances where the wheels do not slip, the system based on the toothed wheel tops is satisfactory, but however, in circumstances where the drive wheels can slip in places, the determination of the forward speed relative to the ground will be more accurate by using another means, for example a differential geo-positioning system.

[0024] According to one embodiment, the determination of the flow control parameter is made from a step lookup table or an interpolation calibration table.

[0025] This correspondence or calibration table expresses the flow control parameter to be applied as a function of the advance speed, but another parameter may also be involved, such as the average distance between the product jet and the target vegetation or the thickness of the target vegetation.

[0026] Accordingly, the relationship between the forward speed and the pulsed airflow (creating the airflow carrying the product jet) can be parameterized and adapted to the target use, whether it be the type of product or the type of agricultural machinery, the characteristics of the fan or the characteristics of the desired air-jet spraying. A single basic software program can thus be used, with the parameterization allowing the spraying function to be customized to the specific application.

[0027] According to one embodiment, it is further provided for the control of one or more solenoid valves controlling the delivery of the product to be sprayed under pressure, depending on the forward speed.

[0028] It is thus possible to control not only the airflow rate in relation to the feed rate but also the quantity of product delivered in relation to the feed rate. This ensures homogeneity of the aerodynamic conditions of delivery of the product even if the speed of the agricultural machine changes during its passage through the vineyard or orchard.

[0029] According to one embodiment, the spraying system comprises at least two fans each driven by a respective motor, each respective motor being controlled according to the flow control parameter.

[0030] In certain configurations, generating the pulsed airflow requires the use of several fans, for example, one fan per side or even one fan per spray column. Advantageously, according to the present invention, the logic for controlling the fan speed to the feed rate applies to each of the fans involved in generating the desired pulsed airflow.

[0031] According to one embodiment, the spraying system further includes a user terminal usable for selecting a parameter table from several and / or for a display function of the advance speed, the target fan speed and the actual fan speed.

[0032] Using the user terminal, the user can start or stop a spraying sequence. Furthermore, the user can select a parameter table corresponding to the product being applied. In addition, the user terminal can display in real time the speeds and rotational speeds representative of the application process of the product in progress.

[0033] According to another aspect of the invention, it relates to a spraying system for a product to be sprayed carried by an airflow to target vegetation, the spraying system being suitable for being mounted on board an agricultural machine, the spraying system comprising at least one fan, with a fan motor allowing several distinct rotation rates, a control unit, and one or more solenoid valves controlling the delivery of a product to be sprayed under pressure, the system being configured, by means of the control unit, to implement the process as described above.

[0034] According to various embodiments, the spraying system can include a boom and a plurality of spray columns in number N, configured to be placed opposite the foliage of a plant or shrub, the number N being between 2 and 11.

[0035] Here, the term "spray column" refers to a subset of spraying elements that are generally aligned in a vertical position in the operating configuration.

[0036] In the operating configuration, the spray columns extend substantially in a vertical position. The direction of product spraying and the flow of the supporting air extends substantially horizontally.

[0037] Spray columns can be configured, for example in a narrow vine configuration, to dispense product on both transverse sides of the spray column. Conversely, spray columns can be configured to dispense product on only one side (treatment of a single half-row).

[0038] According to another aspect of the invention, it relates to an assembly comprising a straddle tractor and a spraying system as described above, the agricultural machine then being formed by the straddle tractor.

[0039] Thus, the straddle tractor carries the spraying system and this assembly forms an autonomous equipment generally equipped with a product tank of a fairly substantial volume, it can treat a large area of ​​vineyard or orchard without having to refuel.

[0040] Alternatively, an assembly consisting of a trailer carrying the spraying system and including a product tank is provided. This trailer can be hitched to any tractor. PRESENTATION OF THE FIGURES

[0041] The invention will be better understood upon reading the following description, given solely by way of example, and referring to the accompanying drawings given by way of non-limiting examples, in which identical references are given to similar objects and on which:

[0042] Fig. 1 is a schematic top view representation of a straddle agricultural machine operating in a vineyard or orchard, the agricultural machine being equipped with a mounted spraying system in which the present invention can be implemented;

[0043] Fig. 2 is a schematic front view representation of the agricultural machine of Fig. 1, illustrating in particular the spray boom with 6 spray columns;

[0044] The [Fig.3] just a particular situation where the agricultural machine is moving on uphill terrain;

[0045] Fig. 4 shows a functional schematic diagram of the spraying system according to an example embodiment;

[0046] The [Fig.5] is a schematic representation of a correspondence chart between the advance speed and a flow control parameter, here the target rotation speed of the fan;

[0047] Fig. 6 is a schematic representation of a flowchart illustrating the proposed process.

[0048] It should be noted that the figures set out the invention in detail to enable implementation of the invention; although not limiting, said figures serve in particular to better define the invention where appropriate. DETAILED DESCRIPTION OF THE INVENTION

[0049] The invention relates to a system for spraying product in liquid form, the product being intended to be projected in the form of droplets onto target vegetation, for example shrub foliage or vineyard foliage.

[0050] In the example illustrated in Figures 1 to 4, a straddle tractor-type agricultural machine 9 is shown from a top view, applying a plant protection product to three rows of vines RI, R2, R3 simultaneously. The vine rows are spaced a distance ER apart. In very common vineyard configurations, ER can be on the order of 60 cm to 90 cm (so-called 'narrow' vines), or ER on the order of 120 cm to 160 cm (so-called 'wide' vines).

[0051] A tractor straddling a row of vines is shown. However, the straddle tractor could straddle two rows of vines. The tractor could also be a non-straddle tractor. The distance DI between the median planes W1, W2 of the main support wheels can range from 160 cm to 250 cm, without these values ​​being limiting. The ground clearance for the straddling function is adapted to the type of plants being treated, with height adjustment possible if necessary.

[0052] The agricultural machine 9, of the straddle tractor type, moves along its longitudinal axis X at a forward speed denoted VA. The determination of the forward speed is discussed later in this document.

[0053] The agricultural machine 9, of the straddle tractor type in the example shown, carries a spraying system 10 for a treatment product.

[0054] The product of interest may also be called the spray product (identified as 8 in [Fig. 4]). It may be a treatment product in general, or more specifically a plant protection product. As a reminder, the product is in liquid form, for example in a tank mounted on the spraying system or more generally in a tank mounted on the tractor or agricultural machinery in question.

[0055] The spraying system 10 includes a boom 24 extending, in use, generally horizontally i.e. transversely to the longitudinal direction of movement of the tractor, i.e. along the transverse axis Y (cf. [Fig.2]).

[0056] The spraying system 10 comprises spraying columns. In the example illustrated in the figures, the spraying system 10 comprises six spraying columns labeled C1, C2, C3, C4, C5 and C6, each column spraying a only one side in this example. Let N be the number of spray columns; N is between 2 and 11.

[0057] The spray columns are intended to be placed opposite a plant / shrub. The target vegetation TV consists of tree foliage, shrub foliage, or vine foliage, without this list constituting a limitation.

[0058] The spraying system 10 comprises at least one fan 7 driven by a fan motor 4. In a typical example, the fan motor 4 is a hydraulic motor, powered by hydraulic pressure PSH from a hydraulic pump 35 arranged in the agricultural machine 9. The hydraulic pump is driven directly or indirectly by the engine MOT of the agricultural machine (see [Fig. 3]). The hydraulic pump may be arranged on the agricultural machine itself or on the tractor that pulls the agricultural machine.

[0059] Advantageously, according to the present invention, the fan motor is provided to allow several distinct rotation speeds. In other words, it is not a fan that is simply controlled in on-off mode. The fan motor can have a plurality of discrete speeds, that is to say, speed increments.

[0060] According to another possibility, the fan motor can be controlled at any speed between 0 and the maximum possible speed. Thus, it will be possible to vary the fan speed according to the forward speed VA of the agricultural machine, particularly with a certain proportionality function.

[0061] The pulsed airflow is channeled through various conduits from the fan area 7 to the outlets of the delivery nozzles 1 in the spray columns.

[0062] The total pulsed airflow, denoted FAP, generated by the fan 7 is divided into several flow branches F1, F2, F3, F4, F5, F6, here six branches, each corresponding to a spray column. The airflow configuration naturally depends on the number of spray columns, as well as the number of fans and the air distribution from the fans to the spray columns.

[0063] In the illustrated example, there is only one fan 7. In other examples not shown in the figures, there may be several fans, in particular two fans, one for each side, or as many fans as there are spray columns.

[0064] The process comprises an iterative performance of the following actions, symbolically illustrated in [Fig.6]:

[0065] S1- an evaluation of the forward speed VA of the agricultural machine relative to the ground,

[0066] S2- a determination, as a function of the forward speed VA, of a parameter of PCD (Pulse Flow Control) is the flow rate control in relation to the pulsed airflow to be delivered.

[0067] S3- the control of the fan motor 4 according to the flow control parameter PCD.

[0068] According to one example, the flow control parameter is a target fan speed. The flow control parameter is determined from a step lookup table or an interpolated calibration table.

[0069] Figure 5 illustrates an example of the dependence of the target fan speed on the forward speed VA of the agricultural machinery. The x-axis represents the forward speed from 0 to 16 km / h, and the y-axis represents the target fan speed coV. As already mentioned, the target fan speed coV is a specific example of the general case where it is a PCD flow control parameter that is made dependent on the forward speed.

[0070] Curve 51 represents discrete step logic. Curve 52 represents continuous logic. The stepless curve can be obtained from a few points and an interpolation between the points.

[0071] In both cases, a certain proportionality is observed between the feed rate and the target fan speed. An additional parameter or a second dimension of calibration can be used, which relates to the distance to the vegetation or the thickness of the vegetation.

[0072] It may be provided that in the event that the advance speed is unavailable, the target fan speed is set to the reference speed coVl, which may or may not be the maximum fan speed.

[0073] According to other examples, one can have a different progressiveness with a continuous proportionality without necessarily being linear.

[0074] Figure 3 shows the situation where the agricultural machine 9 is in a situation of pronounced ascent, with an angle of ascent noted al.

[0075] In such a situation, if the agricultural machine's powertrain reaches its power limit for moving the agricultural machine and turning the accessories, then the decrease in engine speed and advance speed is advantageously accompanied by a simultaneous decrease in the fan speed, which allows some of the power consumed by the fan to be recovered.

[0076] Conversely, in a situation of pronounced descent, the engine speed and the forward speed may increase, or even the wheels may slip; these possible phenomena will be advantageously accompanied by a simultaneous increase in the fan speed to maintain aerodynamic conditions consistent with the actual forward speed.

[0077] In [Fig. 4], reference numeral 1 generally designates the plenum with air nozzles of the spray column. Reference numeral 2 designates a nozzle for projecting the product to be sprayed.

[0078] Regarding the calculation of speed and forward speed, four possible solutions are shown in [Fig. 4]. One of the solutions uses wheel signal counting. More specifically, a toothed target 12, magnetic or mechanical, is used, which moves in relation to a sensor 13, for example, a Hall effect sensor. The signals delivered by the sensor are processed by the control unit 5, which calculates the instantaneous forward speed VA of the tractor (or, in the general case of agricultural machinery, the speed VA of the tractor) from these signals.

[0079] It is noted that the toothed target 12 and the opposite sensor 13 can be arranged on any rotating part connected to the advancement of the agricultural machine.

[0080] A second solution consists of using a satellite geopositioning system and, by adding a time derivative function, deducing the speed of the agricultural machine. For this purpose, the agricultural machine can be equipped with a geoposition receiver, denoted 15. Various systems can be used, for example those known as GPS, Galileo, and GLONASS.

[0081] In one example of implementation, a differential type GPS known as DGPS is used with a stationary GPS base station placed at the end of the field which communicates with the electronic equipment of the agricultural machine.

[0082] According to another example of implementation, the agricultural machine can be equipped with a radar sensor 14, known per se, which emits waves towards the ground and recovers the reflections with a Doppler shift which makes it possible to deduce the forward speed of the tractor relative to the ground independently of any possible slippage of the tractor's wheels.

[0083] According to another implementation example, the agricultural machine can be equipped with a lidar sensor, known per se. The successive point clouds captured by the lidar sensor are processed by software which makes it possible to deduce the forward speed of the agricultural machine.

[0084] According to yet another implementation example, the agricultural machine can be equipped with a video camera. Similar to the previous case, the successive images captured by the camera are processed by software that makes it possible to deduce the forward speed of the agricultural machine.

[0085] According to another example of implementation, an inertial platform 16 can be used which integrates information delivered by a longitudinal acceleration sensor, in order to deduce the forward speed of the tractor.

[0086] Furthermore, it is also provided for the control of one or more solenoid valves 6 controlling the delivery of a product to be sprayed 8 under pressure.

[0087] It is planned to control one or more solenoid valves 6, depending on the feed rate. Depending on the configuration, there may be a single solenoid valve 6 for the entire delivery network to the product spray nozzles or several solenoid valves in order to selectively control a part of the system and the If necessary, isolate part of the system, for example to create borders or a number of rows less than the nominal situation.

[0088] A pump 3 delivers the product under pressure, at pressure PI. This pump can be driven by a hydraulic motor or directly by the tractor's power take-off. A manifold 60 is provided which supplies various delivery pipes 31 of the product to be sprayed to the spray columns.

[0089] Furthermore, the spraying system 10 includes a control unit 5, responsible for determining the tractor's forward speed based on one of the means described above. The control unit also generates a PCD flow control parameter from the forward speed. The control unit 5 then drives a component responsible for implementing the flow control parameter. In the illustrated example, this is directly the fan's rotational speed. In another example, it could be the opening angle of a hydraulic valve that supplies the hydraulic motor mechanically coupled to the fan's impeller.

[0090] The fan speed control can be achieved using a closed loop control system thanks to a sensor placed on the rotor shaft which measures the coVreal rotation speed (see [Fig.6]).

[0091] Optionally, a user terminal 25 is also provided. Using this user terminal, the user can start or stop a spraying sequence. The user terminal is typically installed in the immediate vicinity of the tractor's driver's seat. The user terminal is connected to the control unit 5 via a bus-type electrical connection. The user terminal may be an ISOBus type terminal.

[0092] Furthermore, the user terminal can be used to select a parameter table from among several parameter tables. In addition, user terminal 25 can be used to perform a function for displaying the feed rate, the target fan speed, and the actual fan speed.

[0093] It should be noted that the advantage provided by linking the fan speed to the forward speed is not limited to uphill or downhill situations. It may be necessary to treat certain parts of the plot / vineyard / orchard at a lower speed than the nominal speed, for example, to reduce the noise generated by the forced airflow. The function can also include an economy mode, with a prescribed tractor speed lower than in the nominal mode.

[0094] As an alternative to the configuration shown in the figures and discussed above, the spraying system can be mounted on board a trailer-type agricultural vehicle.

[0095] In this case, the trailer is mechanically coupled to a tractor. In addition, the trailer is hydraulically coupled to the tractor to benefit from the pressurized oil supply from the hydraulic pump on board the tractor. In an alternative or complementary configuration, the trailer equipped with the spraying system may itself include a hydraulic pump driven, for example, by a universal joint shaft connected to the tractor's power take-off.

[0096] It is noted that the tractor's power take-off (PTO) generally rotates at a speed proportional to the speed of the tractor's engine (MOT) and is not related to the forward speed. In all cases, the PTO's rotational speed does not take into account any possible wheel slippage or skidding.

[0097] It should also be noted that the invention is not limited to the embodiments described above. It will indeed be apparent to a person skilled in the art that various modifications can be made to the embodiments described above, in light of the information just disclosed to them.

[0098] In the detailed presentation of the invention given above, the terms used shall not be interpreted as limiting the invention to the embodiment set forth in this description, but shall be interpreted to include all equivalents which can be foreseen by a person skilled in the art by applying their general knowledge to the implementation of the teaching which has just been disclosed to them.

Claims

Demands

1. A method implemented in a straddle agricultural machine (9) capable of straddling a row of vines, the straddle agricultural machine comprising a powertrain (MOT) having a power limit, a spraying system (10) for a product to be sprayed (8) carried by an airflow directed towards target vegetation (TV) comprising at least one fan (7) driven by a fan motor (4), the fan motor being a hydraulic motor powered by a hydraulic pump driven directly or indirectly by the powertrain of the straddle agricultural machine, a control unit (5) configured to control at least one rotational speed of the fan motor, and a means for evaluating the forward speed of the straddle agricultural machine (9), the method comprising: a- advancing the straddle agricultural machine on an uphill path, b- reaching the power limit of the powertrain,c- simultaneous decrease in engine speed and advance rate, d- control by the control unit (5) of a decrease in the fan rotation speed, as a function of the advance rate delivered by the advance rate evaluation means, e- recovery by the powertrain of part of the power consumed by the fan.

2. A method according to claim 1, wherein in step d-, the reduction in the fan rotation speed is determined from a step lookup table.

3. A method according to claim 1, wherein in step d-, the reduction in fan speed is determined from an interpolated calibration table

4. A method according to any one of claims 1 to 3, wherein the spraying system further comprises one or more solenoid valves (6) controlling the delivery of the product to be sprayed under pressure, wherein the method further provides for piloting the solenoid valves as a function of the advance speed (VA).

5. A method according to any one of claims 1 to 4, wherein the spraying system further comprises a user terminal (25) and the method provides for selecting a parameter table from several and / or for a feed rate display function, of the target speed of the fan motor and the actual speed of the fan motor.

6. A straddle agricultural machine (9) capable of straddling a row of vines, comprising: - a powertrain (MOT) having a power limit, - a spraying system (10) for a product to be sprayed (8) carried by an airflow to target vegetation (TV) comprising at least one fan (7) driven by a fan motor (4), the fan motor being a hydraulic motor powered by a hydraulic pump driven directly or indirectly by the powertrain of the straddle agricultural machine, - a control unit (5) configured to control at least one rotational speed of the fan motor, - a means for evaluating the forward speed of the straddle agricultural machine (9), the control unit (5) being configured to control a rotational speed of the fan motor at least as a function of an evaluation of the forward speed (VA) of the straddle agricultural machine relative to the ground,and configured to control a reduction in the fan motor speed when the power limit is reached, so that when the straddle tractor is moving uphill, if the powertrain reaches its power limit, causing a simultaneous decrease in engine speed and forward speed, this decrease in engine speed is accompanied by a control of a reduction in the fan speed, allowing the powertrain to recover some of the power consumed by the fan.

7. A straddle agricultural machine according to claim 6, wherein the means for evaluating the forward speed of the straddle agricultural machine is one and / or the other of the following means: - a geo-positioning system, preferably a differential geo-positioning system (DGPS), with a time-derivative position function, - a system based on frequency signals delivered by a sensor (13) opposite a toothed wheel (12), mechanical or magnetic, in kinematic relationship with a wheel of the straddle agricultural machine, - a system based on a radar sensor (14) interacting with the ground, - an inertial platform (16), comprising at least one longitudinal acceleration sensor and an integration function, with periodic recalibration.

8. Straddle agricultural machine according to any one of claims 6 to 7, wherein the spraying system further comprises a user terminal (25) usable for selecting a parameter table from several and / or for a display function of the forward speed, target fan speed and actual fan speed.

9. Straddle agricultural machine according to any one of claims 6 to 8, wherein the spraying system further comprises one or more solenoid valves (6) controlling the delivery of the product to be sprayed under pressure, wherein it is further provided that the solenoid valves are controlled according to the forward speed (VA).

10. A straddle agricultural machine according to any one of claims 6 to 9, wherein the spraying system comprises a boom (24) and a plurality of spraying columns (C1,C2,C3) in number N, configured to be placed opposite a plant / shrub, the number N being between 2 and 11.

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