PROTECTION DEVICE FOR ROW-CROPS AGAINST CLIMATIC HAZARDS

Abstract

A device (100) for protecting a row crop extending along a Y-axis against climatic hazards, said device comprising at least one retractable protective screen (1a, 1b) having an inflatable structure made of several chambers arranged in fluidic communication with each other, at least one of the chambers being connected to fluidic actuation means for the screen between a deployed position when the screen extends in a direction X, substantially perpendicular to the direction of the Y-axis, and a retracted position when the screen is flattened, in which said screen is supported by a first tensioned cable (2) extending along the Y-axis above the row crop and in which the device comprises means for guiding the translation along the X-direction of said at least one screen (1a, 1b). Figure for the abbreviation: Fig. 2

Description

Title of the invention: DEVICE FOR PROTECTING ROW-IN CROPS AGAINST CLIMATIC HAZARDS

[0001] The present invention relates to the field of agriculture and more particularly concerns a device for protecting against climatic hazards of row crops, such as fruit tree crops, vines or any row crop grown in a field.

[0002] The growth of plants in row crops depends on external weather conditions. Tree crops are subject to numerous climatic hazards: rain, hail, drought, insects, frost, mold, etc. These climatic hazards, which are becoming increasingly frequent and intense, generally lead to a sharp drop in yield, or even the loss of some crops. The need for effective protection against climatic hazards is therefore increasingly felt by farmers in order to significantly limit the impact of these hazards and reduce the use of pesticides currently employed in large quantities.

[0003] Solutions for protecting row crops from hail or rain are known, such as those described in documents FR 2739526 and EP 2944188, which involve covering the crops laterally with films or nets. Installing such films or nets around the crops is done manually, which means that their installation or removal is time-consuming, and therefore these solutions are not suitable for frequent changes in weather conditions.

[0004] Another solution for protecting vines against hail was proposed in document WO 2018 / 049540, which describes a device for deploying a hail-proof roof over a row of vines. The hail-proof roof is supported by cables arranged on either side of the central posts and comprises two parts that deploy and retract on either side of the central posts. Each roof part includes deformable chambers; the roof is deployed by inflating the chambers, and retraction is achieved using a spring system. Thanks to its automatic operation, the device described in this document is indeed better able to adapt to changing weather conditions than the solutions previously described, but at the cost of a complex construction integrating pneumatic inflation means combined with mechanical spring-loaded retraction means, which is difficult to integrate into an agricultural environment and expensive.Furthermore, the width of this device when unfolded is quite small, limited to half the width of the vine row, which severely restricts the area of ​​protection it provides to the crop. However, a wider, yet lightweight, protection area is often needed. to be able to protect crops that occupy a large area, such as tree crops, against various climatic hazards.

[0005] A simplified operating solution for an insulating blind for the roof of a greenhouse is also known from document EP 97051. The insulating blind described in this document is in the form of a retractable screen comprising interconnected inflatable tubular chambers and is operated by pneumatic means that ensure the deployment and retraction of the insulating blind. However, the blind described in this document is arranged between the panes of double glazing, which it covers for the purpose of insulating the greenhouse, and therefore its use is restricted to greenhouse crops.

[0006] An objective of the invention is to remedy the drawbacks of the aforementioned documents and to provide an original solution for a crop protection device in rows allowing the protection of crop rows growing in open ground against several climatic hazards over large areas, while being of simplified construction and whose operation can be easily automated.

[0007] This objective is achieved by the invention which proposes a device for protection against climatic hazards of a row crop extending along an axis Y, said device comprising at least one retractable protective screen having an inflatable structure made on the basis of several chambers arranged in fluidic communication with each other, at least one of the chambers being connected to fluidic actuation means of the screen between a deployed position when the screen extends in a direction X, substantially perpendicular to the direction of the axis Y, and a folded position when the screen is flattened, in which said screen is supported by a first tensioned cable extending along the axis Y above the row crop and in which the device comprises means for guiding in translation along the direction X said at least one screen.

[0008] In other words, the invention proposes a device for protecting row crops, particularly tree crops, against adverse weather conditions. This device comprises a retractable screen made from an inflatable structure actuated by fluidic means, such as pneumatic means. The screen is positioned above the crop and supported by a tensioned cable to form a roof over the row crop. An inflatable structure is lightweight and retractable. In fact, most of the time, the structure must be retracted to be as compact as possible so as not to disrupt tree growth. The structure is only deployed when protection is necessary, particularly in cases of frost, hail, heat waves, rain, etc.However, the device of the invention uses an inflatable structure whose ratio between the retracted surface area and the deployed surface area is as low as possible, and it is arranged so as not to hinder the growth of trees.

[0009] Furthermore, the deployment of the inflatable structure is ensured by inflation and the folding is ensured by vacuum, by connecting the inflatable structure to a pneumatic network, and this without using a mechanical actuation device, which gives more construction simplicity to the solution and allows to reduce its manufacturing costs.

[0010] Furthermore, the inflatable structure of the invention is supported by a tensioned cable, which means that such a retractable inflatable structure arrangement makes it possible to protect crops by adapting to the external agricultural environment. Indeed, an inflatable structure offers flexibility and adaptability to plots with uneven terrain and structures with cable support posts installed with tight tolerances. Retractable inflatable structures require only elastic fasteners and fluidic means, such as an air network which itself includes flexible hoses, making it adaptable to the terrain's configuration. This type of solution is therefore very simple and easy to implement in an orchard with row crops.

[0011] The translational guidance means may include at least one tensioned flexible cable. This solution allows the inflatable structure to be guided between its deployed and flattened positions using flexible cables capable of adapting to the terrain in which the row crop is located. Furthermore, such a second tensioned flexible cable, perpendicular to the first tensioned cable which supports the device, and more flexible than the first tensioned cable, allows it to tilt under the weight of hail, forming a hailstone evacuation slope.

[0012] Said second tensioned flexible cable can be arranged inside a rigid tube of length at least equal to that of the inflatable structure in its deployed position.

[0013] Said inflatable structure may comprise several elongated chambers, each chamber extending along the direction of the Y axis and being retractable along the X direction. Such a structure thus forms a roof with two sides extending in a substantially horizontal plane on either side of the first tensioned cable.

[0014] At least one chamber may include a sheath attached to its upper part, and said sheath is suitable for receiving a rod. This makes it possible to reinforce the upper wall of a chamber made of a flexible material.

[0015] Said sheath may include at least one opening intended to be passed through said second tensioned flexible cable. This ensures good translational guidance of the inflatable structure during its deployment and folding.

[0016] The inflatable structure of said screen may comprise several sheaths through which rods are passed uniformly distributed over its width in the direction of the X axis. This ensures good translational guidance over the entire length of the inflatable structure.

[0017] One end chamber of the inflatable structure can be supported by said first tensioned cable, and at least one other chamber of the inflatable structure is suspended from said second tensioned flexible cable. One end of the structure is thus fixed to the first tensioned cable, and the other chambers slide in translation along the second tensioned flexible cable.

[0018] The device of the invention may comprise two retractable screens arranged adjacently on either side of the Y-axis and suspended from said first tensioned cable. Such a device thus forms a gable roof, each gable being formed by a retractable screen.

[0019] The translational guidance means may be common to both screens. This simplifies the construction, as the second tensioned flexible cable passes above and is supported by the first tensioned cable.

[0020] Said guiding means may include at least two second tensioned flexible cables that are perpendicular to the first tensioned cable and may be supported by the latter. The two flexible cables are parallel to each other and ensure better translational guidance of the inflatable structure.

[0021] The device of the invention may include fluidic actuation means that can perform the simultaneous deployment and retraction of said screens such that the free end of the first screen is able to move in the opposite direction to that of the free end of the second screen. This makes it possible to deploy the two symmetrical screens from a common base, resulting in a very compact construction in the flattened position of the screens and a very wide coverage in the deployed position.

[0022] The device of the invention may comprise several pairs formed of a first and a second screen arranged side-by-side in the direction of the Y-axis on the first tensioned cable. This makes it possible to cover a crop row along its entire length.

[0023] The device of the invention may include at least one sensor and a central control unit for the fluidic actuation means based on data received from said sensor. This ensures automatic operation of the device of the invention.

[0024] The invention will be better understood from the following description, which is based on the following figures: Fig. 1 is a schematic top view illustrating the protective device of the invention in its folded position installed above a row of fruit trees; [Fig.2] is a perspective view illustrating the protection device of the invention in its deployed position; [Fig.3] is a schematic front view of a chamber forming part of the inflatable structure of the device of the invention; [Fig.4] is a schematic view illustrating the insertion of a rod into the sheath of a chamber of the inflatable structure of the device of the invention; [Fig.5a] is a front view and [Fig.5b] is a side view of the entire [Fig.4] during deployment; [Fig.5c] illustrates the device of [Fig.5b] in its fully deployed position; [Fig.6a] illustrates the device of the invention in a problem situation and [Fig.6b] illustrates the solution to this problem.

[0025] In the various figures, identical or similar elements bear the same reference. Their description is therefore not systematically repeated.

[0026] Figure 1 schematically illustrates a row crop of the orchard type, in which a weather protection device 100 of the invention is installed above a row of fruit trees. The device 100 of the invention will be better explained with the help of the reference frame constituted by the Cartesian coordinate system XYZ in Figures 1 and 2.

[0027] Figure 1 shows four rows of fruit trees above which the devices 100 of the invention are installed, illustrated in various positions of their operation. Thus, starting from the left side of Figure 1, the first device 100 is shown in its partially deployed position, the next two devices 100 are shown in a fully deployed position, and the last is shown in its fully folded position. The rows of trees can be spaced, for example, between 3 and 5 meters apart. Above a row of trees, first tensioned cables 2 extend in the direction of the Y-axis; they are supported by posts 14 along the row. The first cables 2 are tensioned by tensioning means and fixed to the ground at their ends 2a, each tensioned cable 2 supporting a device 100 of the invention. Thus, the first 2 tensioned cables are rigid objects.The device 100 of the invention comprises, in the example illustrated in [Fig. 1], two retractable screens la, 1b, each comprising an inflatable structure, arranged in pairs on either side of the Y-axis. Several pairs of screens la, 1b can be arranged one after the other to cover a row of crops along its entire length. Each screen la, 1b of the device 100 of the invention is capable of deploying in a direction X, perpendicular to the direction of the Y-axis, so that the device 100 can take the form of a substantially horizontal roof over the row of crops, on either side of each of the first two tensioned cables 2. It can be seen from [Fig. 1] that, in the folded position, the device of the invention is very compact and discreet and is designed to allow plant growth.

[0028] The device 100 illustrated in [Fig.2] comprises a set of retractable screens, more particularly several pairs of retractable screens la, 1b connected together along a first tensioned cable 2 or ridge cable.

[0029] According to the invention, retractable screens la, 1b are supported by a first cable 2 stretched along the Y-axis above a row of trees in an orchard. The retractable screens la, 1b are fixed on either side of the first cable 2 and each comprises an inflatable structure having a set of chambers of variable volume, fixed together back-to-back along their longest dimension L parallel to the Y-axis and connected to fluidic actuation means. The fluidic actuation means comprise a pneumatic network having flexible tubes 3 connected to a pump via valves. On command, these fluidic actuation means blow or draw air into the tubes 3. When inflated, the screens la, 1b deploy horizontally along the X-axis above the crops and form a roof of width "1" on each side of the first cable 2.Air is introduced and removed by a valve 5 welded to the rear wall 29a, 29b ([Fig.5c]) of a retractable screen la, 1b, wall which is located near the first cable 2. The same network can supply several pairs of retractable screens la, 1b, in which case valves 4 are installed at the inlet of each pair of screens.

[0030] According to the invention also, the device includes means for guiding in translation along the X direction of said screen la, 1b. In the example illustrated in the figures, the means for guiding in translation of the retractable screens la, 1b include second flexible cables 7 stretched along the direction of the X axis which cooperate with the inflatable chambers of each of the screens so as to guide them in translation in their movement of deployment and retraction.

[0031] In what follows, we will explain in more detail the geometry of the different chambers that make up the inflatable structure of a retractable screen la, 1b. as best seen in Figures 5b and 5c where the retractable screen is shown in the deployed position. Each retractable screen comprises several elongated chambers with a general hexagonal cross-section. The chambers are made from flexible strips cut from a thermoplastic film, for example a polyurethane (PU) film. Thus, to make a chamber, rectangular strips 20 are cut from a polyurethane film and welded together in pairs at the center by a rectangular central weld 22. Then, two pairs thus obtained are welded together in pairs around their periphery, obtaining a rectangular peripheral weld 21. Such a strip 20 is best seen in [Fig.[3], figure in which the peripheral weld 21 and the central weld 22 are represented by dashed lines. Such "peel" type welds facilitate the movement of the chambers into a folded position during suction. Next, passage orifices 23. Openings are drilled in the vertical intermediate walls of the chambers 20 to allow air from an inflation valve to pass from one chamber to the other. In other words, the passage openings 23 are made in all the vertical walls of the chambers of a retractable screen 1a, 1b, except for the end vertical walls 28a, 28b, and 29a, 29b, respectively. Indeed, the end vertical walls serve to close a module, and some, for example the rear walls 29a, 29b, have inflation / deflation valves. The various peripheral welds 21 or central welds 22 can be high-frequency welds or impulse welds. In one variant, the welds can be replaced by bonding.

[0032] By way of example, the thickness of the PU film used is 300 µm and the 20 strips have a width along the Z-axis of between 50 and 150 mm. The length L of a chamber measured along the Y-axis is at least equal to its width and can reach several meters.

[0033] This results in an inflatable structure for each retractable screen. Two retractable screens la, 1b thus obtained are welded back-to-back at their upper part, preferably by securing them to a flap 15, which is positioned astride the first tensioned cable 2. The screens la, 1b are symmetrical with respect to the first cable 2. The flap 15 is a flexible polyurethane sheet or a sheet of textile material. In an alternative embodiment, the screens la, 1b are welded together at their rear chambers 29a, 29b without the interposition of a flap and are positioned astride the first cable 2.

[0034] The inflatable structures of the retractable screens 1a, 1b are identical. Each inflatable structure is preferably inflated with pressurized air, the inflation pressure being between 0.1 and 0.3 bar and preferably equal to 0.13 bar. The chambers of the inflatable structure are deflated by suction. It is preferable to limit the suction pressure to -0.03 bar so that the chambers can open easily during inflation in the deployment phase.

[0035] It is observed that the inflatable structure thus obtained is a flexible, accordion-type structure. When air is evacuated to retract the modules, the welded, accordion-type strip structure promotes retraction along the X-axis, and the strips flatten out in the YZ plane, one on top of the other. However, when such an accordion-type structure is suspended, forces oppose this movement, and when these forces are too great (for example, those due to friction, gravity, etc.), the chambers of the inflatable structure will collapse along the Z-axis, and the module will remain deployed in this state. To promote proper retraction of the different chambers during deflation of the structure, the inflatable structure is suspended from the second set of tensioned flexible cables 7 located at the top, above the weld. superior, of certain chambers. In this way, the natural movement of the latter is to close in a vertical plane.

[0036] Furthermore, it is observed that, without internal inflation pressure, the chambers flex in the YZ plane in their deflated state. It is therefore necessary to prevent them from inflating unevenly with creases, which could hinder deployment. As more clearly seen in [Fig. 4], to overcome this problem, a sheath 8 extending along the Y-axis is added along the upper peripheral weld 21 of certain chambers. The sheath is open at its ends and has several transverse openings 9 along its entire length. A rigid rod 10 is then inserted into the sheath 8, this rod covering the entire length L of the chamber. As more clearly seen in [Fig. 5a], the rod 10 passes over the second set of tensioned flexible cables 7, which guide the inflatable structure in translation.Thus, the rigid rods 10 have the dual role of stiffening the flexible inflatable structure and guiding this structure during its inflation and deflation.

[0037] Retraction occurs from the chamber located furthest forward, at end 28a, respectively 28b, to the chamber closest to the first taut cable 2, end chambers 29a, respectively 29b. Consequently, after a while, an accumulation of the folded chambers exerts pressure at a point B on the second taut flexible cable 7, causing it to tilt at a specific angle in the XZ plane ([Fig. 6a]). When operating above the orchard, the second taut flexible cable is less rigid than the first taut cable 2. The force required to retract this mass is then too great, and the last deployed chambers tend to collapse along the Z axis, resulting in an incomplete retraction of the retractable screen. To prevent this, the second flexible cable 7 is inserted into a rigid tube 11.The rigid tube 11 is preferably an aluminum tube coated externally with a low-friction coating, such as PTFE, allowing the rods to slide on the tube with virtually no friction. The tube 11 is fixed at one end to the first tensioned cable 2. Thus, the inflatable structure of each retractable screen slides freely on it with minimal friction and a nearly zero, consistent slope, enabling each retractable screen to fold completely flat and occupy very little space on either side of the first tensioned cable 2.

[0038] Several guiding means are used for a retractable screen, for example, two flexible cables 7 tensioned for each pair of retractable screens. In order to ensure proper operation of the entire device, the guiding means, such as the second tensioned cables 7 and the rigid tubes 11, must be parallel to each other and perpendicular to the first tensioned cable 2. By way of example, the tolerance of The perpendicularity of the second cables 7 is approximately + / - 25mm at a distance of 800mm from the first cable 2.

[0039] The first tensioned cable 2 is preferably a steel cable or a DELTEX® cable with a diameter between 6 and 8 mm. These cables are tensioned using known type tensioning means, for example using a tensioning block and tackle and a cable clamp and are fixed to the ground.

[0040] The second tensioned flexible cables 7 are bungee cords with a diameter between 6 and 10 mm, preferably 8 mm. Their tension is determined according to the dimensions of the screens la, 1b so that, under the weight of the hail, the assembly can tilt to make it fall, while still allowing the device to withstand the wind. In one embodiment, each second tensioned flexible cable 7 is tensioned using known tensioning means, for example, a tensioning block and tackle and a cable clamp, and is attached at both ends to two lateral posts.

[0041] In the example illustrated in [Fig. 1], the second set of flexible cables 7 are connected together to form a network which is fixed by means of rigid end cables 16, such as steel cables, to end posts 14 located on a side of the orchard free of crops. As an example, the distance D between two end posts 14 is between 5 and 10 m. The second set of flexible cables 7 of the network is supported by the first set of tension cables 2. The tension of the first set of tension cables 2 is determined based on the cumulative weight of the network of second set of flexible cables 7 and that of the devices 100, all of which are supported by the first set of cables 2.Thus, the first 2 tensioned cables must be sufficiently rigid to support the weight of the device 100, in particular that of the retractable screens la, 1b and their guiding means, in particular the second tensioned flexible cables 7, and also that of objects which may land on the device (hailstones, rainwater, birds, etc).

[0042] In operation, when the fluidic actuation means are actuated to send an inflation fluid in the direction of arrow G of [Fig.2] into the two retractable screens la and 1b, deployment is obtained and, when the fluid is withdrawn from the structure in the direction D of [Fig.2], the retractable screens la, 1b are simultaneously folded back by moving the free end 28a of the first retractable screen in the opposite direction to that of the free end 28b of the second retractable screen 1b.

[0043] Such a protective device, comprising retractable screens each with a flexible inflatable structure, allows for ease of use and maintenance, excellent adaptability to the agricultural environment, and good weather resistance. The simple construction of this system offers modular protection for tree crops at a lower cost. Thanks to this system, one can, by making minimal changes to the infrastructure of existing crops, covering them in an automated manner with means resistant to the environment of use.

[0044] In an advantageous embodiment, the device of the invention comprises at least one sensor and a central unit for automatically controlling the fluidic actuation means based on data received from said sensor. Thus, such a sensor may be a meteorological parameter sensor that measures humidity, temperature, wind speed, etc. The central unit can thereby automatically control the operation of the fluidic actuation means for the retractable screens of the device. In a variant, the device can be controlled remotely by an operator.

[0045] Other variants and embodiments of the invention may be envisaged within the scope of the invention as claimed.

Claims

Demands

1. Device (100) for protection against climatic hazards of a row crop extending along an axis Y, said device comprising at least one retractable protective screen (la, 1b) having an inflatable structure made on the basis of several chambers arranged in fluidic communication with each other, at least one of the chambers being connected to fluidic actuation means of the screen between a deployed position when the screen extends in a direction X, substantially perpendicular to the direction of the axis Y, and a folded position when the screen is flattened, in which said screen is supported by a first tensioned cable (2) extending along the axis Y above the row crop and in which the device comprises means for guiding in translation along the direction X said at least one screen (la, 1b).

2. Device according to claim 1, characterized in that said translational guidance means comprise at least one second tensioned flexible cable (7).

3. Device according to the preceding claim, characterized in that said second tensioned flexible cable (7) is arranged inside a rigid tube (11) of length at least equal to that of the inflatable structure in its deployed position.

4. Device according to any one of the preceding claims, characterized in that said inflatable structure comprises several elongated chambers, each chamber extending along the direction of the Y axis and being retractable along the X direction.

5. Device according to the preceding claim, characterized in that at least one chamber comprises a sheath (8) integral with its upper part and in that said sheath (8) is suitable for receiving a rod (10).

6. Device according to the preceding claim, characterized in that said sheath (8) includes at least one opening (9) intended to be passed through by said second tensioned flexible cable (7).

7. Device according to the preceding claim, characterized in that the inflatable structure of said screen (la, 1b) comprises several sheaths (8) through which rods are passed uniformly distributed over its width in the direction of the X axis.

8. Device according to any one of claims 4 to 7, characterized in that an end chamber (29a, 29b) of the inflatable structure is supported by said first tensioned cable (2) and that at least one other chamber (28a, 28b) of the inflatable structure is suspended from said second tensioned flexible cable (7).

9. Device according to any one of the preceding claims, characterized in that it comprises two retractable screens (la, 1b) arranged adjacently on either side of the Y axis and suspended from said first tensioned flexible cable.

10. Device according to the preceding claim, characterized in that said translational guidance means are common to said two screens (la, 1b).

11. Device according to the preceding claim, characterized in that said translational guidance means comprise at least two second tensioned flexible cables (7) which are perpendicular to the first tensioned cable and are supported by the latter.

12. Device according to any one of claims 9 to 11, characterized in that it comprises fluidic actuation means capable of achieving the simultaneous deployment and folding of said screens (la, 1b) so that the free end (28a) of the first screen (la) is capable of moving in the opposite direction to that of the free end (28b) of the second screen (1b).

13. A device according to any one of claims 9 to 12, characterized in that it comprises several pairs formed of a first (1a) and a second (1b) screen arranged side-by-side in the direction of the v axis

14. 1. Device according to any one of the preceding claims, characterized in that it comprises at least one sensor and a central control unit for the fluidic actuation means based on data received from said sensor.

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