AUTOMATED PRUNING DEVICE

Abstract

Automated pruning device The present invention relates to an automated pruning device (1), remarkable in that it comprises at least: - a frame (2) arranged to surround at least partly the trunk of a tree to be pruned, - energy means making it possible to meet the energy needs of the automated pruning device (1) while limiting its weight and optimizing its autonomy, - transfer means making it possible to move the automated pruning device (1) in a stable and secure manner along the trunk of the tree to be pruned, and - cutting means guaranteeing precise cutting of the branches of said tree. Fig 1

Description

Title of the invention: AUTOMATED PRUNING DEVICE Technical field of the invention

[0001] The present invention relates to the general field of forestry. It relates more specifically to an automated pruning device, also called a pruning robot, that is to say a device for automatically cutting the living or dead branches of a tree arranged along the trunk under the crown of the tree. State of the art

[0002] In the field of forestry, it is known to resort to pruning coniferous trees such as Douglas fir or hardwood trees such as poplars, in order to produce quality wood. Indeed, during growth, the branches are included in the wood and give knots reducing the aesthetic and mechanical qualities of the wood produced. In addition, pruning not only improves the conformation of the stems by reducing the decline, but also has a positive impact on the soil and biodiversity because the supply of light following pruning facilitates the progressive decomposition of humus and pruned branches and returns nutrients to the soil.

[0003] After harvesting, the mechanical characteristics of the wood obtained depend directly on the number, height and quality of pruning. Indeed, except in rare cases for native forest species, the dead branches of a tree do not fall off on their own and cause, during the growth of the tree, the presence of knots which degrade the mechanical characteristics of the wood.

[0004] Thus, to obtain high-quality wood, it is known to carry out an initial pruning of trees up to 3 m in height when the trees are between 10 and 15 years old. Three to five years after this first pruning, a second pruning is carried out up to 6 m in height. Finally, three to five years after the second pruning, a third pruning is carried out up to 9 m in height. However, in certain situations, the second and third prunings may be carried out at the same time.

[0005] Furthermore, the quality of pruning depends on the precision of the cut made. Indeed, if the branch is cut too close to the trunk, part of the trunk may be damaged, causing healing problems for the tree. On the contrary, if the branch is cut too far from the trunk, the residue from the branch may form a stub which will cause the formation of a black knot in the wood. To obtain wood with optimum quality, it is then advisable to cut each branch after the flange supporting the start of the branch from the trunk.

[0006] To do this, pruning professionals traditionally use a cutting tool mounted on a pruning pole. The cutting tool may correspond to a loppers, a saw, electric pruning shears or a chainsaw. To carry out pruning, the professional positions the cutting tool from the ground, flush with the base of the branch to be pruned. However, this manual technique is particularly long for pruning the different branches of a tree and it does not allow for precise reach of high branches, i.e. branches extending more than 5 m from the ground. However, this manual technique is long and painful, and has an impact on the professional's physique (musculoskeletal disorders). To make this technique less traumatic, it is possible to combine these pruning tools with a cradle or a squirrel, but this entails a much higher treatment cost and risks for professionals.

[0007] To achieve faster and safer pruning, several companies have attempted to develop automated pruning devices. For the purposes of the invention, an "automated" pruning device corresponds to a pruning device in which the cutting of branches is not carried out manually by an operator who selects each branch to be cut and positions a cutting tool against the selected branch. An operator is nevertheless necessary to position and then control, remotely and safely, the movement of the automated pruning device.

[0008] These automated pruning devices conventionally comprise a chassis on which is fixed at least one motor which drives in rotation four wheels mounted pivotally on the chassis, these wheels allowing the movement of the pruning device along the trunk of a tree. These automated pruning devices also comprise clamping means on the tree associated with a removable part intended to encircle the trunk and to be fixed on either side of the chassis. This removable part further comprises two free wheels intended to form a counter-support for the four motorized wheels of the chassis. Thus, when an operator wants to prune a tree, he must position the four motorized wheels of the chassis against a tree trunk and fix the removable part to grip the trunk of the tree.When the automated pruning device is clamped around the tree trunk, the operator can control the movement of said automated pruning device and the actuation of the motorized cutting members (tiller, cutter, etc.) to carry out pruning.

[0009] However, this type of automated pruning device has a number of disadvantages. First of all, this type of automated pruning device is heavy, bulky, difficult to handle, and presents a significant risk of jamming when climbing along the trunk of the tree. Furthermore, this type of automated pruning device is particularly unstable when climbing. This instability causes cutting difficulties for the motorized cutting members and does not guarantee optimal and constant cutting quality over the entire height of the tree.

[0010] Finally, the type of engine(s) used by this type of automated pruning device is either thermal or electric. In the first case, the thermal engine is heavy, bulky and difficult to handle and, in the second case, the engine uses batteries whose capacity significantly limits the rate and duration of work and whose weight significantly increases that of the automated pruning devices. Summary of the invention

[0011] The aim of the present invention is therefore to propose an efficient automated pruning device, easy to handle and to implement by a single operator, while guaranteeing sufficient working autonomy and constant cutting quality over the entire height of the tree, said automated pruning device making it possible to prune trees at a sustained rate and for at least half a working day even in places that are difficult to access, while significantly limiting the impact on the environment.

[0012] In accordance with the invention, an automated pruning device is therefore proposed, remarkable in that it comprises at least: - a frame arranged to surround at least partly the trunk of a tree to be pruned, - energy means integral with said frame equipped with a hybrid electric motor comprising a thermal engine associated with a reducer, powered by the gasoline contained in a tank, and driving a generator producing an electric current suitable and necessary for the proper functioning of the automated pruning device, - transfer means enabling the automated pruning device to be moved in a stable and secure manner along the trunk of the tree to be pruned, and - cutting means guaranteeing precise cutting of the branches of said tree.

[0013] According to a particular embodiment, the frame is generally C- or U-shaped, and comprises a longitudinal slot opening into a longitudinal internal space arranged to accommodate the trunk of the tree to be pruned and having a substantially vertical longitudinal axis A, said frame determining at least one upper face extending substantially perpendicular to said longitudinal axis A.

[0014] The energy means preferably comprise a battery charged by the electric current produced by the generator.

[0015] The rotation speed of the thermal engine is controlled so that the generator delivers an electric current whose voltage and intensity are directly adapted to the needs of the automated pruning device.

[0016] The transfer means are advantageously provided with several trolleys receiving two superimposed wheels, each trolley being mounted movably on the chassis, according to a direction D perpendicular to the longitudinal axis A of the chassis, each wheel being inflated with low-pressure gas and independently driven in rotation, around an axis perpendicular to the direction D of movement of the corresponding carriage and to the longitudinal axis A of the chassis, by an electric motor.

[0017] For this, said automated pruning device comprises linear movement means associated with each of the carriages and configured to move the latter in said direction D, said linear movement means advantageously comprising at least: - a guide carriage fixed to the carriage in said direction D and cooperating with a complementary guide rail fixed to the chassis, and - a nut block fixed to the carriage and cooperating with a worm screw secured to the chassis, extending in said direction D and driven in rotation by an electric motor.

[0018] Advantageously, the cutting means comprise at least: - a crown pivotally mounted on the chassis around the longitudinal axis A of the latter and being at least partly removable to allow said automated pruning device to be placed around said tree, and comprising a toothed wheel cooperating with a pinion pivotally mounted on the chassis around an axis parallel to the longitudinal axis A of the latter, and driven in rotation by a first electric motor, and - a cutting member for cutting the branches of the tree to be pruned, said cutting member being integral with said crown and capable of moving relative to the latter in a direction D' perpendicular to said axis A.

[0019] Said cutting member advantageously comprises a chain guide extending substantially perpendicular to the crown and receiving a chain driven by a second electric motor, and is associated with linear movement means comprising at least: - a guide rail fixed to the cutting member in said direction D' and cooperating with a complementary guide element fixed to the crown, - a rack fixed on said cutting member extending in said direction D' and cooperating with a pinion pivotally mounted on the crown and driven in rotation by a third electric motor, and - a deflector allowing the branch to be moved aside so that it can be cut at its junction with the trunk, without the risk of blocking the chain of the cutting device.

[0020] According to a particular embodiment, the automated pruning device is associated with measuring devices and geolocation devices in order to collect and record a plurality of information items making it possible to monitor the pruning, this information being chosen from the following group comprising at least: - the diameter of the tree at the time of pruning, - the volume of the pruned tree, - geolocation of the pruned tree, - the pruned height, - the number of whorls and / or branches cut, or - the number of trees pruned during the pruning session.

[0021] Said automated pruning device comprises control means comprising at least one electronic card associated with a remote control and being configured to operate, autonomously, remotely and in complete safety, the automated pruning device 1 according to the needs and measurements of different sensors.

[0022] Said sensors are advantageously of the type: - proximity sensors to detect the presence of the trunk of the tree to be pruned in order in particular to adapt the position of the carriages in relation to said trunk so as to adapt the position and movement of the cutting member, - movement sensors to measure the distance traveled by the automated pruning device along the trunk of the tree to be pruned, or - force and / or stress sensors to measure the stresses experienced by the various electric motors. Brief description of the figures

[0023] Other advantages and characteristics will emerge more clearly from the following description of an embodiment of the invention with reference to the appended figures in which:

[0024] [Fig-1] is a perspective view of an automated pruning device according to the invention,

[0025] [Fig.2] is a top view of the automated pruning device of [Fig.l],

[0026] [Fig.3] is a perspective view of the chassis of the automated pruning device of the [Fig.l],

[0027] [Fig.4] is a perspective view of the moving means of the automated pruning device of [Fig.l],

[0028] [Fig.5] is a front view of the moving means of [Fig.4],

[0029] [Fig.6] is a perspective view of the cutting means of the pruning device automated from [Fig.l].

[0030] [Fig.7] is a top view of the cutting means of [Fig.6],

[0031] [Fig.8] is a bottom view of the cutting means of [Fig.6]. Description of the embodiments

[0032] In Figures 1 and 2, there is shown, in accordance with the invention, an automated pruning device 1, also called a pruning robot, comprising at least: - a chassis 2 arranged to surround at least partly the trunk of the tree to be pruned, - energy means making it possible to meet the energy needs of the automated pruning device 1 while limiting its weight and optimizing its autonomy, - transfer means making it possible to move the automated pruning device 1 in a stable and secure manner along the trunk of the tree to be pruned, and - cutting means guaranteeing a precise cut of the branches of said tree, that is to say a cut after the bead supporting the departure of the branch from the trunk.

[0033] The energy, transfer and cutting means of the automated pruning device 1 are integral with the chassis 2 of the latter and are described, in detail, further on.

[0034] With reference to [Fig. 3], said frame 2 is arranged to at least partially surround the trunk of the tree to be pruned, when the automated pruning device 1 is placed on said tree. For this, the frame 2 is generally C-shaped or U-shaped, and comprises a longitudinal slot 3 opening into a longitudinal internal space 4 arranged to accommodate the trunk of the tree to be pruned and having a substantially vertical longitudinal axis A, also called hereinafter longitudinal axis A of the frame 2. Furthermore, said frame 2 determines at least one upper face 5 extending substantially perpendicular to said longitudinal axis A.

[0035] Here, the term "substantially perpendicular" refers to the fact that two elements make an angle between them of between 60 and 120°. Similarly, here, the term "substantially vertical" or "substantially horizontal" refers to an element forming an angle with the vertical of between -30 and +30° or 60 and 120°.

[0036] Concerning energy means, it is known that electricity is a rather clean source of energy, because electric motors do not emit greenhouse gases. However, even if electricity is an energy that is easy to transport, to use an electric motor, it is preferable to be close to a power source, failing which, it is necessary to implement at least one rechargeable battery. However, for an automated pruning device 1 according to the invention that has to work at a sustained rate for at least half a day, the volume of battery to be transported would become very large and would significantly increase the weight of the automated pruning device 1.

[0037] For this, with reference to figures 1 and 2, the energy means of the automated pruning device 1 use a hybrid type of energy and are equipped with a hybrid electric motor 6, that is to say an association of an electric motor and a thermal engine, generally gasoline. In the present invention, said hybrid electric motorization 6 comprises a thermal engine 7 advantageously associated with a reducer 8 and powered by the gasoline contained in a tank, driving a generator 9 producing an electric current suitable and necessary for the proper functioning of the automated pruning device 1, that is to say for the movement of the latter along a trunk and for cutting branches, said thermal engine 7, reducer 8 and generator 9 being integral with the chassis 2.

[0038] Furthermore, the electric current delivered by the generator 9 will also make it possible to charge a battery 10 used to overcome a possible technical problem of the thermal engine 7 (empty fuel tank, mechanical problem, etc.) or even a peak in electrical consumption, and to allow the automated pruning device 1 to descend from the tree in the event of the thermal engine 7 stopping. Given its occasional and short-term use, said battery 10 has a low capacity and, consequently, is of reduced size and weight.

[0039] To start the thermal engine 7, two reliable and resistant technologies are known, namely an electric starter and a hand starter. The thermal engine 7 is advantageously equipped with a hand starter, not shown in the figures, because it is a widely proven and widespread technology in the forestry environment. However, the thermal engine 7 may be equipped with an electric starter powered by the battery 10, without departing from the scope of the present invention.

[0040] The major problem to be solved with the hybrid electric motor 6 of the automated pruning device 1 according to the invention is to obtain an electric current delivered by the generator 9 allowing proper operation of said automated pruning device 1 and, where appropriate, optimal charging of said battery 10. A first solution consists of operating the thermal engine 7 at a constant rotation speed, then converting the electric current delivered by the generator 9 in order to adapt it to the optimal voltage and intensity for the battery 10. This first solution is certainly simple, but it has the disadvantage of being inefficient. This is why, in particular to control the charging of the battery 10 with the hybrid electric motor 6 of the automated pruning device 1 according to the invention, a second, more efficient solution is implemented.The latter consists of controlling the rotation speed of the thermal engine 7 so that the generator 9 delivers an electric current whose voltage and intensity are directly adapted to the needs of said automated pruning device 1 and, where appropriate, the charge of the battery 10. According to this second solution, the electric current produced by the generator 9 is no longer converted.

[0041] A person skilled in the art will have no difficulty in determining the values of the voltage and intensity of the electric current produced by the generator 9, so that they are adapted to the needs of the automated pruning device 1, in particular depending on the different electric motors implemented in said automated pruning device 1 and described later.

[0042] It is understood that with this hybrid electric motorization 6, the autonomy of the automated pruning device 1 is increased without having to resort to batteries of large dimensions and weight. Furthermore, the thermal engine 7 only serving to drive the generator 9, its power is limited, which reduces its weight and its fuel consumption, the impact on the environment of the automated pruning device 1 is therefore significantly limited.

[0043] To obtain a stable movement along the trunk of the tree to be pruned (i.e. in a rectilinear and substantially vertical direction), with reference to Figures 3 to 5, the automated pruning device 1 comprises transfer means provided with several carriages 11 receiving two superimposed wheels 12, each carriage 11 being mounted movably on the chassis 2 of said automated pruning device 1, in a direction D perpendicular to the longitudinal axis A of the longitudinal internal space 4 of the chassis 2. This characteristic makes it possible to grip the tree to be pruned by adapting to the diameter of the trunk of the latter, or on the contrary to release the automated pruning device 1 from said tree. For this, the automated pruning device 1 comprises linear movement means 13 associated with each of the carriages 11 and configured to move the latter in said direction D.

[0044] Said linear displacement means 13 advantageously comprise at least: - a guide carriage 14 fixed on the carriage 11 in said direction D and cooperating with a complementary guide rail 15 fixed on the chassis 2, and - a nut block 16 fixed on the carriage 11 and cooperating with a worm screw 17 secured to the chassis 2, extending in said direction D and driven in rotation by an electric motor 18.

[0045] Thus, the rotation of the worm screw 17 in one direction causes the carriage 11 to move along the latter in one direction of movement and the rotation of the worm screw 17 in the other direction causes the carriage 11 to move along the latter in an opposite direction of movement.

[0046] According to an advantageous embodiment, the linear displacement means 13 comprise four guide carriages 14 fixed in pairs respectively to the upper and lower ends of the carriage 11, each of the pairs of guide carriages 14 cooperating with a complementary guide rail 15 fixed to the chassis 2.

[0047] Even if this configuration of the linear displacement means 13 is particularly simple and effective, it is understood that the latter may either comprise at least one guide rail fixed on the carriage 11 and cooperating with a guide carriage fixed on the chassis 2, or be of a completely different type and comprise, for example, a ball bushing - guide shaft assembly, without departing from the scope of the present invention. Similarly, the nut block 16 - worm screw 17 assembly of the linear displacement means 13 may be of a completely different type such as, for example, a pinion - rack assembly, without departing from the scope of the present invention.

[0048] Furthermore, each of the wheels 12 is advantageously inflated with gas, conventionally air, at low pressure, to be able to more easily overcome the deformations of the trunk of the tree to be pruned so as to avoid any jamming of the automated pruning device 1 and to guarantee its adhesion and stability during its movement along said tree, but also to avoid damaging the external layer of said tree.

[0049] To enable the automated pruning device 1 to move along the tree to be pruned, each wheel 12 is independently driven in rotation, around an axis perpendicular to the direction D of movement of the corresponding carriage 11 and to the longitudinal axis A of the longitudinal internal space 4 of the chassis 2, by an electric motor 19. The use of an electric motor 19 to drive each wheel 12 in rotation allows for simplicity of control and rapid and precise feedback of information relating to the rotation of each wheel 12. This makes it possible in particular to know whether one of the wheels 12 is forcing or, on the contrary, spinning in a vacuum, and to alert the operator if necessary.

[0050] According to an advantageous embodiment, the carriages 11 are angularly offset in a substantially uniform manner. However, the angular offset between the carriages 11 arranged on either side of the longitudinal slot 3 of the chassis 2 of the automated pruning device 1 is preferably between 105 and 165° to facilitate the positioning of said automated pruning device 1, through its longitudinal slot 3, around the trunk of the tree to be pruned.

[0051] To obtain a precise cut of the branches of the tree to be pruned, with reference to Figures 6 to 8, the automated pruning device 1 comprises cutting means comprising a crown 20 pivotally mounted on the upper face 5 of the chassis 2 around the longitudinal axis A of its longitudinal internal space 4 and being at least partly removable, at the level of the longitudinal slot 3 of said chassis 2, to allow said automated pruning device 1 to be placed around said tree, then to reconstitute said crown 20. For this, the crown 20 comprises a toothed wheel 21 cooperating with a pinion 22 pivotally mounted on the upper face 5 of the chassis 2 around an axis parallel to the longitudinal axis A of the latter, and driven in rotation by a first electric motor 23.

[0052] Said cutting means also comprise at least one cutting member 24 for cutting the branches of the tree to be pruned, said cutting member 24 being integral with said crown 20 and capable of moving relative to the latter in a direction D' perpendicular to said longitudinal axis A of the chassis 2, so as to be able adapt to the diameter of the tree and position itself at an optimal distance from the trunk, and to carry out a precise cut of the branches.

[0053] For reasons of ease of use and maintenance, the cutting member 24 is advantageously of the chain type, but, it goes without saying that it could be of a completely different type such as, for example, a milling cutter or a circular saw, without departing from the scope of the present invention. Thus, said cutting member 24 comprises a chain guide 25 extending substantially perpendicular to the crown 20 and receiving a chain, not shown, driven by a second electric motor 26.

[0054] As described previously, the cutting member 24 is able to move relative to the crown 20 in a direction D' perpendicular to said longitudinal axis A of the chassis 2. For this, the cutting member 24 is associated with linear movement means 27 advantageously comprising at least: - a guide rail 28 fixed on the cutting member 24 in said direction D' and cooperating with a complementary guide element 29 fixed on the crown 20, and - a rack 30 fixed on said cutting member 24 extending in said direction D' and cooperating with a pinion 31 pivotally mounted on the crown 20 and driven in rotation by a third electric motor 32.

[0055] Thus, the rotation of the pinion 31 in one direction causes the cutting member 24 to move along the guide rail 28 in a translation direction and the rotation of the pinion 31 in the other direction causes the cutting member 24 to move in an opposite direction.

[0056] Even if this configuration of the linear displacement means 27 of the cutting means is particularly simple and effective, it is understood that the latter may either comprise at least one guide element fixed on the cutting member 24 and cooperating with a guide rail 28 fixed on the crown 20, or be of a completely different type and comprise, for example, a ball bushing - guide shaft assembly, without departing from the scope of the present invention. Similarly, the rack 30 - pinion 31 assembly of the linear displacement means 27 of the cutting means may be of another type such as, for example, a complementary ball screw - nut assembly, without departing from the scope of the present invention.

[0057] For the same reasons as those described previously, the use of electric motors to drive the crown 20, the cutting member 24 and the chain allows for simplicity of control and rapid and precise feedback of information relating to the rotation of the crown 20 and the translation of said cutting members 24 and the chain (and therefore the cutting of the branches).

[0058] Finally, the cutting member 24 advantageously comprises a deflector 33 making it possible to move the branch aside so that the latter can be cut at its junction with the trunk, without risk of blocking the chain of the cutting member 24.

[0059] Furthermore, according to an advantageous embodiment, the automated pruning device 1 according to the invention is associated with measuring devices and geolocation devices in order to collect and record a plurality of information making it possible to monitor the pruning.

[0060] This information is chosen from the following group comprising at least: - the diameter of the tree at the time of pruning, - the volume of the pruned tree, - geolocation of the pruned tree, - the pruned height, - the number of whorls and / or branches cut, or - the number of trees pruned during the pruning session (per hour or working day).

[0061] Finally, it goes without saying that the automated pruning device 1 according to the invention also comprises a plurality of sensors such as, for example: - proximity sensors for detecting the presence of the trunk of the tree to be pruned in order in particular to adapt the position of the carriages 11 relative to said trunk so as to adapt the position and movement of the cutting member 24, - movement sensors for measuring the distance traveled by the automated pruning device 1 along the trunk of the tree to be pruned, or, - force and / or stress sensors for measuring the stresses experienced by the various electric motors.

[0062] Furthermore, the automated pruning device 1 according to the invention comprises control means, not shown, comprising at least one electronic card associated with a remote control and being configured to operate, autonomously, remotely and in complete safety (without risk of injury to the operator), the automated pruning device 1 according to the needs and measurements of the different sensors.

[0063] Thus configured, the automated pruning device 1 according to the invention is used in the manner described below.

[0064] First of all, an operator checks the condition of the automated pruning device 1 according to the invention and prepares it for a pruning session (filling the fuel tank, checking the condition of the chain of the cutting member 24, etc.).

[0065] Then it starts the hybrid electric motor 6 in order to be able to operate the different electric motors of the automated pruning device 1.

[0066] Then, the operator partially dismantles the crown 20 of the cutting means and places the automated pruning device 1 around the tree to be pruned.

[0067] The operator starts the linear movement means 13 associated with each of the carriages 11 to come and grip the trunk of said tree, then raises said crown 20.

[0068] Then, the operator measures and programs the distance that the automated pruning device 1 must travel along said trunk.

[0069] Once the pruning is finished, either the operator lowers the automated pruning device 1, or the latter lowers autonomously. The operator then records the information allowing the pruning to be monitored. It goes without saying that the automated pruning device 1 may also descend autonomously before the end of the pruning, for example, if the automated pruning device 1 can no longer climb the tree or cut branches.

[0070] However, if the pruning cannot be completed satisfactorily, the operator must, if necessary, intervene physically to complete the pruning in good conditions. Thus, for example, if the automated pruning device 1, if the hybrid electric motor 6 is broken or if cutting a branch is impossible, the operator may have to climb the tree to unjam said automated pruning device 1, repair the hybrid electric motor 6 or cut the branch.

[0071] The automated pruning device 1 according to the invention finds a particular application for pruning Douglas fir trees, but it goes without saying that it could be adapted for pruning trees of other species such as, for example, spruce, fir, pine or even larch, or even poplar.

[0072] Finally, it goes without saying that the examples of automated pruning devices 1 in accordance with the invention which have just been described are only particular illustrations, in no way limiting the invention.

Claims

1. Claims Automated pruning device (1) comprising at least: - a frame (2) arranged to surround at least part of the trunk of a tree to be pruned, - energy means integral with said chassis (2) equipped with a hybrid electric motor (6) comprising a thermal engine (7) associated with a reducer (8), powered by the gasoline contained in a tank, and driving a generator (9) producing an electric current suitable and necessary for the proper functioning of the automated pruning device (1), - transfer means for moving the automated pruning device (1) in a stable and secure manner along the trunk of the tree to be pruned, and - cutting means guaranteeing precise cutting of the branches of said tree, said automated pruning device (1) being characterized in that said frame (2) is generally C- or U-shaped, and comprises a longitudinal slot (3) opening into a longitudinal internal space (4) arranged to accommodate the trunk of the tree to be pruned and having a substantially vertical longitudinal axis A, in that said frame (2) determines at least one upper face (5) extending substantially perpendicular to said longitudinal axis A, and in that the cutting means comprise at least: - a crown (20) pivotally mounted on the upper face (5) of the chassis (2) around the longitudinal axis A of the latter and being at least partly removable to allow said automated pruning device (1) to be placed around said tree, and comprising a toothed wheel (21) cooperating with a pinion (22) pivotally mounted on the chassis (2) around an axis parallel to the longitudinal axis A of the latter, and driven in rotation by a first electric motor (23), and - a cutting member (24) for cutting the branches of the tree to be pruned, said cutting member (24) being integral with said crown (20) and capable of moving relative to the latter in translation in a direction D' perpendicular to said axis A.

2. Automated pruning device (1) according to any one of claims 1 or 2 characterized in that the energy means comprise a battery (10) charged by the electric current produced by the generator (9).

3. Automated pruning device (1) according to any one of claims 1 to 3, characterized in that the rotation speed of the thermal engine (7) is controlled so that the generator (9) delivers an electric current whose voltage and intensity are directly adapted to the needs of the automated pruning device (1).

4. Automated pruning device (1) according to any one of claims 1 to 4 characterized in that the transfer means are provided with several carriages (11) receiving two superimposed wheels (12), each carriage (11) being mounted movably on the chassis (2), in a direction D perpendicular to the longitudinal axis A of the chassis (2), each wheel (12) being inflated with low pressure gas and independently driven in rotation, around an axis perpendicular to the direction D of movement of the corresponding carriage (11) and to the longitudinal axis A of the chassis (2), by an electric motor (19).

5. Automated pruning device (1) according to claim 5 characterized in that it comprises linear displacement means (13) associated with each of the carriages (11) and configured to move the latter in said direction D, said linear displacement means (13) advantageously comprising at least: - a guide carriage (14) fixed on the carriage (11) in said direction D and cooperating with a complementary guide rail (15) fixed on the chassis (2), and - a nut block (16) fixed on the carriage (11) and cooperating with a worm screw (17) secured to the chassis (2), extending in said direction D and driven in rotation by an electric motor (18).

6. Automated pruning device (1) according to claim 7 characterized in that said cutting member (24) comprises a chain guide (25) extending substantially perpendicular to the crown (20) and receiving a chain driven by a second electric motor (26), and is associated with linear displacement means (27) comprising at least: - a guide rail (28) fixed on the cutting member (24) in said direction D' and cooperating with a complementary guide element (29) fixed on the crown (20), - a rack (30) fixed on said cutting member (24) extending in said direction D' and cooperating with a pinion (31) pivotally mounted on the crown (20) and driven in rotation by a third electric motor (32), and - a deflector (33) making it possible to move the branch aside in order to be able to cut the latter at the level of its junction with the trunk, without risk of blocking the chain of the cutting member (24).

7. Automated pruning device (1) according to any one of claims 1 to 8, characterized in that it is associated with measuring members and geolocation members in order to collect and record a plurality of information making it possible to monitor the pruning, this information being chosen from the following group comprising at least: - the diameter of the tree at the time of pruning, - the volume of the pruned tree, - the geolocation of the pruned tree, - the pruned height, - the number of whorls and / or branches cut, or - the number of trees pruned during the pruning session.

8. Automated pruning device (1) according to any one of claims 1 to 9, characterized in that it comprises control means comprising at least one electronic card associated with a remote control and being configured to operate, autonomously, remotely and in complete safety, the automated pruning device 1 according to the needs and measurements of different sensors.

9. Automated pruning device (1) according to claim 10 characterized in that the sensors are such as: - proximity sensors for detecting the presence of the trunk of the tree to be pruned in order in particular to adapt the position of the carriages (11) relative to said trunk so as to adapt the position and movement of the cutting member (24), - movement sensors making it possible to measure the distance traveled by the automated pruning device (1) along the trunk of the tree to be pruned, or else, - force and / or stress sensors to measure the stresses experienced by the various electric motors.

Images