DEVICE AND METHOD FOR MACHINING AN EXTREMITY OF A BASE PANEL IN PREPARATION FOR MACHINING IT BY FRICTION WELDING PROCESS

Description

DOMAINE TECHNIQUE GENERAL ET ART ANTERIEUR

[0001] The present invention relates to the field of manufacturing an aeronautical structure from elementary metal panels which are assembled by welding, in particular, by friction stir welding known to those skilled in the art under its English name "Friction Stir Welding" or "FSW".

[0002] To perform friction stir welding, two ends of elementary metal panels are positioned adjacently, then a pin is driven in high-speed rotation at the interface between the two elementary metal panels in order to locally melt the material of the ends of the elementary metal panels and thus weld them.

[0003] In practice, basic metal panels cannot be welded directly after fabrication and must be prepared before welding. (Referring to the...) figure 1A A left-hand elementary metal panel 1G and a right-hand elementary metal panel 1D are shown, each comprising a central metal body 10, for example, made of aluminum. In this example, each central metal body 10 has a lower face F1 with a coating 11 and an upper face F2 without such a coating. As an example, each coating 11 is in the form of a layer of pure aluminum resulting from the rolling of the elementary panel 1G, 1D.

[0004] In the case of friction stir welding, one objective is to remove the coating 11 (also called "cladding") so that the coating material does not mix with the material of the central metal body 10 during welding. More generally, the aim is to control the thickness of the end of the metal panel to be welded.

[0005] A preparation step involves locally removing the coating 11 from the ends of the elementary metal panels 1G, 1D to be welded. This step is known to those skilled in the art as "removal of the coating." The removal step is complex because it requires removing the coating 11 with high precision. If the removed thickness is too small, the coating 11 is not completely removed, and the coating material may mix with the material of the central metal body 10, which would degrade the weld bead. Conversely, if the removed thickness is too large, the thickness of the central metal body 10 may be too small and less than the length of the friction pin. In this case, the weld bead will not have optimal qualities.

[0006] To accurately remove the coating 11 using a machining tool, a precise measurement step is required to determine the position of each individual metal panel 1G, 1D. This measurement step is performed by contact. In practice, a measuring tool makes an initial measurement pass along a predetermined theoretical path along the end of each individual metal panel 1G, 1D to determine the vertical deviation between the theoretical path and the actual profile of that end. Using the theoretical path and the vertical deviation, a corrected path is calculated. A further contact measurement step can be performed based on the corrected path to detect any further vertical deviations. The measurement step is stopped when the final corrected path matches the actual profile, i.e., when the vertical deviation is zero.Once the measurement step is completed, the coating 11 is removed U1 at the end of each elementary panel 1G, 1D by a machining tool using the last corrected trajectory (. Figure 1B ). Then the elementary panels 1G, 1D are butted together and welded by friction stir welding. After welding, the elementary panels 1G, 1D are joined by a weld bead 12 as illustrated in the figure 1C .

[0007] The measurement steps are cumbersome because they are very long and expensive, as they are performed manually by operators. Furthermore, such a measurement step lacks the optimal reliability required to meet increasingly stringent standards. Even if the measurement step were automated, it would still not meet the reliability requirements.

[0008] The invention therefore aims to remedy these drawbacks by proposing a device and a method for machining one end of an aeronautical metal panel for the purpose of its friction stir welding.

[0009] Although the invention originated for an elementary panel having a coating, the invention applies to any elementary panel for which it is desired to remove thickness from at least one face of one end of said elementary panel.

[0010] The GB1413106 A document relates to a device for working on different longitudinal sections of an elongated part (metal bar, sheet, etc.), in particular, at several different longitudinal positions. The purpose of the device is to perform different operations at several longitudinal positions automatically. Such a device is incapable of removing a thickness precisely. The device is in no way suitable for machining one end of a panel to remove a thickness from one of its faces.

[0011] Document JP H10 52773 A concerns a friction stir welding (FSW) assembly device. The device is in no way suitable for machining one end of a panel to remove thickness from one of its faces. PRESENTATION GENERALE DE L'INVENTION

[0012] For this purpose, the invention relates to a machining device as defined in claim 1.

[0013] Thanks to the machining device according to the invention, the panel element is precisely guided within the machining device's frame of reference. This eliminates the need for prior measurement of the panel's position, increasing reliability and saving time. The use of guiding and pressure elements allows for local constraint of the panel element so that it extends in a predetermined plane during machining. Thus, even if the panel element has one or more curves overall, it is locally deformed to extend perfectly along the horizontal reference direction. This allows for the precise removal of a thickness from the first face, since it extends along the horizontal reference direction.

[0014] Preferably, the horizontal reference direction is defined between the two vertices of the guiding elements.

[0015] Preferably, the machining device comprises two pressure elements, each pressure element being mounted symmetrically to a guide element with respect to the horizontal reference direction so as to sandwich the panel element. The panel element is thus perfectly held between two reference points. At each reference point, a guide element cooperates with a pressure element to prevent any movement of the panel element.

[0016] The machining device is configured to move from upstream to downstream. It includes two upstream and two downstream guide elements. Preferably, the machining device also includes two upstream and two downstream pressure elements. This advantageously increases the positioning accuracy of the machining tool by preventing any deformation of the workpiece panel. Indeed, the panel is held between four reference points, preventing any local deviation.

[0017] Preferably, each pressure member is movable relative to the horizontal reference direction. Thus, each pressure member allows the stress to be adjusted when the thickness of the panel varies along its length. According to the invention, each guide member is fixed relative to the horizontal reference direction. In other words, even if the guide member is capable of rotating about an axis to guide the panel, its position remains fixed relative to the horizontal reference direction to define a stable reference frame within the machining device.

[0018] In one aspect, the lateral dimension of the guide elements, defined orthogonally to the horizontal reference direction, is larger than the machining lateral dimension of the machining tool to ensure optimal guidance of the machined portion by the guide elements. In other words, the guide elements downstream of the machining tool remain in contact with an unmachined portion of the end of the workpiece to prevent any misalignment. The machining tool is aligned with the guide elements along the horizontal reference direction.

[0019] According to another aspect, the machining tool is offset laterally from the horizontal reference direction defined by the guide members so that the guide members do not come into contact with a machined portion of the end of the elementary panel during the movement of the machining device.

[0020] Preferably, the guide elements are spaced horizontally between 50 mm and 150 mm apart, preferably between 60 mm and 150 mm. Such a spacing allows for high-precision guidance close to the machining tool.

[0021] Only the frame is configured to move during machining; the relative position of the machining tool with respect to the guide elements is defined precisely. In other words, the machining tool's position remains fixed within the guide elements' reference frame, thus eliminating the need to consider the overall reference frame of the machining tool. The frame can therefore follow the profile of the panel end. When the guide elements are positioned, the machining tool is guaranteed to be in the correct machining position. This precision is crucial, which is highly advantageous for a deburring operation to remove a calibrated thickness.

[0022] Preferably, the machining device includes at least one blower configured to evacuate machining chips away from the guide and / or pressure elements. Such a blower prevents machining chips from accumulating between the workpiece and a pressure or guide element, which would affect the positioning of the workpiece within the machining device and thus the machining accuracy.

[0023] Preferably, the machining device includes at least one sweeping element configured to sweep at least one face of the workpiece panel. Such a sweeping element captures any machining chips resting on the workpiece panel, thus maintaining high machining accuracy. Preferably, the sweeping element is positioned between the machining tool and a guide element. This prevents the guide element from being pressed against a machining chip that would affect its positioning.

[0024] The use of blowing / suction / sweeping devices allows machining chips to be treated while maintaining a high feed rate.

[0025] The frame comprises a lower and an upper section with adjustable vertical spacing. The guide elements are mounted on the lower section, while the machining tool is mounted on the upper section of the frame. This allows for very precise definition of the machining height.

[0026] In a preferred design, the frame features a movable base configured to allow the machining device to rotate around a vertical axis. This enables the machining tool to rotate 180°, allowing for the machining of a left-hand panel followed by a right-hand panel. While ensuring high precision, the machining device remains user-friendly, facilitating the welding of panels together.

[0027] The invention also relates to a machining and welding system for one end of an elementary panel, the machining and welding system comprising at least one support device for at least one elementary panel, a device for moving a functional unit relative to the support device and a machining device as previously described, the machining device being connected to the functional unit so as to allow the removal of a thickness of at least one face of an elementary panel mounted on a support device.

[0028] Advantageously, the machining and welding system allows the elementary panel to be positioned precisely and then the machining device to be moved along its end in order to remove a thickness of material.

[0029] According to a preferred design, the machining and welding system comprises two support devices and a friction stir welding device connected to the functional unit to enable friction stir welding of the ends of the panel elements mounted on the support devices. The support devices thus provide support for the panel elements during machining and subsequent friction stir welding. The machining and welding steps can be performed consecutively, improving the bond quality of the panel elements.

[0030] The invention further relates to a method of machining one end of an elementary panel for the purpose of its friction stir welding as defined in claim 9.

[0031] Thanks to the invention, the elementary panel is constrained in the machining reference frame of the machining device, thus avoiding the need for a time-consuming and imprecise position measurement step.

[0032] Preferably, the elementary panel is positioned close to the end of the elementary panel to be machined. The end of the elementary panel extends in a cantilevered fashion during machining.

[0033] Preferably, at least one face of the elementary panel is coated, and the machining device is moved relative to the elementary panel along the horizontal reference direction to machine the coating. Preferably, the first face of the elementary panel is machined because its position is determined with high precision by the guide elements.

[0034] Preferably, the process includes a friction stir welding step of two elementary panels after machining. The elementary panels are machined individually and then butted together for friction stir welding.

[0035] Because the machining stage is carried out precisely, the quality of the friction stir welding is optimal. PRESENTATION DES FIGURES

[0036] The invention will be better understood upon reading the following description, given solely by way of example, and referring to the attached drawings in which: There figure 1A is a cross-sectional view of the ends of elementary aeronautical panels prior to a decladding stage, The figure 1B is a cross-sectional view of the ends of elementary aeronautical panels after a decladding step, The figure 1C is a cross-sectional view of the ends of elementary panels after friction stir welding, The figure 2 is viewed from the perspective of a machining and welding system according to one embodiment of the invention, The figure 3 is a front view of a machining device according to one embodiment of the invention, The figure 4 is a rear view of the machining device of the figure 3 , There figure 5 is viewed in perspective of the machining device of the figure 3 , There figure 6 is a zoomed-in view of a pressure element of the machining device of the figure 5 , There figure 7 is a horizontal cross-sectional view of the machining device of the figure 3 , There figure 8 is a schematic view of the positioning of the machining tool relative to the horizontal reference direction. figure 9 is a side view of a step in the removal of a coating from an elementary panel by the machining device according to one embodiment of the invention. figure 10 is a perspective view of the withdrawal stage of the figure 9 , There figure 11 is a top view of the machining of a left-hand elementary panel and then a right-hand elementary panel. figure 12 is a top view of the welding of the elementary panels of the figure 11 , and La figure 13 is a top view of the welded elementary panels of the figure 12 .

[0037] It should be noted that the figures explain the invention in detail for implementing the invention, and these figures can of course be used to better define the invention where appropriate. DESCRIPTION D'UN OU PLUSIEURS MODES DE REALISATION ET DE MISE EN OEUVRE

[0038] With reference to the figure 2 , it represents a machining and welding system 100 of two elementary panels 1G, 1D.

[0039] The machining and welding system 100 includes a left support device 130G on which a left elementary panel 1G is positioned and a right support device 130D on which a right elementary panel 1D is positioned.

[0040] As illustrated in the figure 1A A basic 1G, 1D panel comprises a metal body 10 defining two opposing faces F1, F2, at least one face of which is covered with a coating 11 to be removed. In this example, the metal body 10 is made of aluminum alloy and has a thickness between 1 mm and 3 mm. The coating 11 is made of pure aluminum and has a thickness between 0.1 mm and 0.3 mm. Preferably, the coating 11 has a constant thickness. The metal body 10, on the other hand, has a thickness that can vary along the end of the 1G, 1D panel. As mentioned previously, the coating 11 must be removed precisely at the end of the 1G, 1D panel to ensure optimal weld quality. Due to its thinness, such a basic 1G, 1D panel remains flexible and can be flattened by plastic deformation even if it has one or more curves.

[0041] The invention will be presented for an elementary panel 1G, 1D comprising a coating to be removed on the first face F1, but the invention also aims at an elementary panel 1G, 1D not comprising a coating and for which it is desired to remove a thickness from one face of the metal body 10.

[0042] The machining and welding system 100 includes a movement device 110 which in this example takes the form of a movement gantry as illustrated in the figure 2 The displacement device 110 includes a functional unit 120 on which various devices can be mounted, in particular, a machining device 2 and a friction stir welding device 140. The functional unit 120 advantageously provides electrical, mechanical, hydraulic, pneumatic energy to the connected devices.

[0043] As will be shown later, the movement device 110 allows, on the one hand, the machining device 2 to be moved to remove the coating at the end of each elementary panel 1G, 1D and, on the other hand, the friction stir welding device to join the elementary panels 1G, 1D together. In other words, thanks to the machining and welding system 100, two elementary panels 1G, 1D are welded quickly and conveniently.

[0044] In this example, with reference to the figure 2 , the support devices 130G, 130D are configured to fixedly support the elementary panels 1G, 1D while keeping their end to be machined cantilevered so as to facilitate the passage of the machining device 2.

[0045] Thanks to the machining and welding system 100 according to the invention, the machining device 2 is positioned precisely relative to an elementary panel 1G, 1D which is held fixedly and then the machining device 2 is moved along one end of the elementary panel 1G, 1D in order to machine it precisely.

[0046] With reference to figures 3 à 10 , a machining device 2 is presented according to an embodiment of the invention for machining one end of a left elementary panel 1G in view of its friction stir welding.

[0047] As illustrated in figures 3 et 4 The machining device 2 comprises a frame 20 and two guide members 3, mounted on the frame 20 and aligned along a horizontal reference direction Xr. The guide members 3 are configured to guide a first face F1 of an elementary panel 1G in order to precisely define its position. The machining device 2 further comprises a machining tool 4 mounted on the frame 20. The machining tool 4 is positioned between the two guide members 3 at a vertical position determined relative to the horizontal reference direction Xr in order to remove at least the coating 11 from the elementary panel 1G. Again, with reference to the figure 3 , the machining device 2 includes two pressure members 5 configured to exert pressure on the second face F2 of elementary panel 1G so as to press the elementary panel 1G against the guide members 3.

[0048] Thanks to such a machining device 2, an elementary panel 1G is positioned precisely and reliably in the reference frame of the machining device 2, which ensures very high precision machining guaranteeing optimal friction stir welding.

[0049] The different components of the machining device 2 will now be presented individually.

[0050] As illustrated in the figure 4 The chassis 20 of the machining device 2 allows the various components to be supported as will be shown later.

[0051] In this example, the frame 20 comprises a lower part 20A on which the guide elements 3 are mounted and an upper part 20B on which the machining tool 4 is mounted. The vertical distance between the lower part 20A and the upper part 20B is adjustable, in particular by means of a vernier 72 or a micrometer stop, which allows indirect adjustment of the vertical position of the machining tool 4 relative to the horizontal reference direction Xr. Such adjustment offers high precision. For example, a positioning error of less than 0.05 mm can be achieved.

[0052] In this example, with reference to the figure 7 The frame 20 includes a movable base 21 configured to allow the machining device 2 to rotate around a vertical axis Z. The movable base 21 can pivot relative to the upper part 20B of the frame 20 around a vertical axis Z in order to change the orientation of the machining device 2 to machine either a left-hand elementary panel 1G or a right-hand elementary panel 1D as illustrated in the figure 11 In this example, the machining device 2 can rotate 180°. With reference to the figure 7 , the chassis 20 has clamping jaws 22 to hold the mobile base 21 fixedly relative to the upper part 20B in both usage configurations, the clamping jaws 22 being loosened to change configuration.

[0053] As illustrated in figures 3 et 4 The machining device 2 comprises two guide elements 3 configured to guide a first face F1 of the elementary panel 1G, in this example, the lower face F1. Each guide element 3 is in the form of rollers to allow rolling guidance without risk of marking / scratching the lower face F1 of the elementary panel 1G.

[0054] The guide elements 3 are mounted on the frame 20 and aligned along a horizontal reference direction Xr. The guide elements 3 are rotationally movable to allow rolling guidance along the horizontal reference direction Xr. Thus, the guide elements 3 form a frame of reference specific to the frame 20. Preferably, as illustrated in the figure 8 The horizontal reference direction is defined at the apex of the guide members 3. The accuracy ΔZ3 between the center of a guide member 3 and the horizontal reference direction Xr is less than 0.05 mm as illustrated in the figure 8 Preferably, each guide element 3 is rigid to provide the lowest possible positioning tolerance. Each guide element 3 preferably has an external polymer coating to limit the risk of marking the elementary panel 1G.

[0055] Preferably, in reference to the figure 8 The guide elements 3 are spaced horizontally by a distance d3, which must be minimal to ensure effective support while being large enough to provide working space for the machining tool 4 between the guide elements 3 and prevent chip insertion. Preferably, for a machining tool 4 with a diameter of 50 mm, a distance d3 between 50 mm and 150 mm is suitable, preferably between 60 mm and 150 mm. Such a spacing is small compared to the radius of curvature of an elementary panel 1G, which allows the elementary panel 1 to be considered locally planar between the guide elements 3 when it is pressed against them.

[0056] Subsequently, it is assumed that the machining device 2 moves along the arrow AV, that is, from left to right on the figure 3 The leftmost guide element 3 is designated the "upstream guide element," while the rightmost guide element 3 is designated the "downstream guide element." The terms upstream and downstream are defined with respect to the horizontal reference direction.

[0057] In order to remove the coating 11 at the end of the elementary panel 1G, the machining device 2 includes a machining tool 4 mounted on the frame 20, in particular, on its upper part 20B. As illustrated in the figure 3 The machining tool 4 is positioned between the two guide elements 3 at a vertical position determined relative to the horizontal reference direction Xr. The vertical position of the machining tool 4 is easy to guarantee since it is defined by adjusting the vertical distance between the lower part 20A and the upper part 20B of the frame 20. Unlike prior art, which required very precise prior detection of the position of the elementary panel 1G, the elementary panel 1 is guided in the frame 20's reference frame, for which the position of the machining tool 4 is perfectly defined. Machining reliability is thus greatly improved.

[0058] In this example, the machining tool 4 includes a machining surface for machining a bottom face but can also include other machining surfaces for machining a top face and / or a side face (flank) of the end of the elementary panel 1G. Thus, the machining tool 4 allows for complete machining of the end of the elementary panel 1G. As an example, the machining tool 4 is driven in rotation in the vertical direction at a rotational speed of 2000 to 4000 rpm.

[0059] Preferably, the lateral dimension of the guide elements 3, defined orthogonally to the horizontal reference direction Xr, is larger than the lateral machining dimension of the machining tool 4 to allow optimal guidance of the machined portion by the guide elements 3. For example, the width of the guide elements 3 is 10 mm, while the lateral machining dimension is approximately 3 mm. Thus, the guide elements 3 downstream of the machining tool 4 remain in contact with an unmachined portion of approximately 7 mm from the end of the elementary panel 1G to prevent any positioning errors. The machining tool 4 is aligned with the guide elements 3 along the horizontal reference direction Xr.

[0060] Alternatively, the machining tool 4 is offset laterally with respect to the horizontal reference direction Xr defined by the guide members 3 so that the guide members 3 are offset with respect to the machined portion of the end of the elementary panel 1G when the machining device 2 is moved.

[0061] As mentioned previously, still with reference to the figure 3 The machining device 2 includes two pressure members 5 configured to exert pressure on the second face F2 of the elementary panel 1G so as to press the elementary panel 1G against the guide members 3. In order to achieve optimal guidance, the pressure members 5 are aligned vertically with the guide members 3. The leftmost pressure member 5 is designated "upstream pressure member" while the rightmost pressure member 5 is designated "downstream pressure member".

[0062] Thus, the end of the elementary panel 1G is sandwiched in two different horizontal positions, upstream and downstream of the machining tool 4, in order to ensure alignment of the end of the elementary panel 1G with the horizontal reference direction Xr relative to which the machining tool 4 is positioned with high precision.

[0063] In this embodiment, the pressure members 5 are identical. For the sake of clarity and conciseness, only the upstream pressure member 5 will be presented with reference to the figures 5 et 6 .

[0064] With reference to the figure 6 The upstream pressure member 5 includes a roller 51 to allow for rotational guidance without risk of marking / scratching the upper face F2 of the panel 1. Similar to a guide member 3, the roller 51 is rigid to provide the lowest possible positioning tolerance and preferably has an outer polymer coating to limit the risk of marking the elementary panel 1G. The upstream pressure member 5 also includes a cylinder 52 to exert a downward vertical force towards the upstream guide member 3. In this example, the cylinder 52 is connected to the roller 51 by a mechanism 53, enabling a curved stroke. However, it is understood that the cylinder 52 could be connected directly to the roller 51.

[0065] As illustrated in the figure 6 The cylinder 52 of the upstream pressure member 5 extends horizontally and has, at its head, a pin 521 which is connected to the mechanism 53. The mechanism 53 is a longitudinal piece with a lower end 531 connected to the roller 51 by a pivot joint 534 and an upper end 532 with a longitudinal slot 533 in which the pin 521 of the cylinder 52 can move by means of a sliding pivot joint. The longitudinal piece forming the mechanism 53 is articulated to the upper part 20B of the frame 20 about an axis 54. Thus, the upstream pressure member 5 tightens / loosens the elementary panel 1G by performing kinematics along an arc of a circle, which allows a gradual and controlled vertical pressure to be exerted on the upper face F2 of the elementary panel 1G.

[0066] To tighten a basic 1G panel, with reference to the figure 6 The cylinder 52 extends to the right and the pin 521 enters the longitudinal slot 533 to rotate the mechanism 53 clockwise around the axis 54, which moves the roller 51 downwards against the elementary panel 1G along an arc-shaped path. Conversely, to loosen an elementary panel 1G, the cylinder 52 contracts to the left and the pin 521 moves back up into the longitudinal slot 533 to rotate it counterclockwise around the axis 54, which moves the roller 51 vertically upwards away from the elementary panel 1G along an arc-shaped path.

[0067] Advantageously, each pressure member 5 includes a pressure regulating element, preferably integrated into the cylinder 52, to calibrate the pressure applied to the panel element 1G during clamping. Such a pressure regulating element makes it possible to apply a substantially constant pressure even when the thickness of the panel element 1G is not constant. Thus, in the case of excess thickness, the roller 51 of the pressure member 5 is raised, and the pressure is adjusted to achieve optimal clamping of the panel element 1G. Preferably, the pressure regulating element is in the form of an electronic calculation unit that is functionally connected to the cylinder 52. Preferably, the pressure force exerted by a pressure member 5 is between 10 N and 300 N, in particular, less than 150 N. It is understood that a pressure member could apply a higher pressure force, in particular, up to 5000 N.

[0068] Two guide elements 3 associated with two pressure elements 5 (one set upstream and one set downstream) have been presented, but it is understood that a greater number of guide elements 3 and pressure elements 5 could be suitable. In particular, four guide elements 3 associated with four pressure elements 5 (two sets upstream and two sets downstream) optimize the dimensional control of the elementary panel 1G to improve the positioning accuracy of the machining tool 4, notably preventing the elementary panel 1G from being warped.

[0069] With reference to the figure 3 The machining device 2 includes two global alignment elements 71, specifically of the hopper type. Similarly, the machining device 2 includes an upstream global alignment element 71 located upstream of the upstream guide element 3 and a downstream global alignment element 71 located downstream of the downstream guide element 3. These global alignment elements 71 allow for centering the end of an elementary panel 1G prior to machining. Thus, the elementary panel 1G is progressively constrained to precisely control its position within the reference frame of the machining device 2.

[0070] The overall alignment members 71 are aligned along the horizontal reference direction Xr. Each overall alignment member 71 has a shape that converges along the horizontal reference direction Xr towards the machining tool 4. Such overall alignment members 71 allow the end of the elementary panel 1G to be guided globally before constrained guidance is achieved in the immediate vicinity of the machining tool 4 with the guide members 3 and the pressure members 5. In this example, each overall alignment member 71 has two angled plates, but it is understood that one or more rollers could also be suitable.

[0071] Still referring to the figure 3 The machining device 2 also includes two upper blowing elements 61, specifically, one upper blowing element 61 located upstream of the machining tool 4 and one upper blowing element 61 located downstream of the machining tool 4. The upper blowing elements 61 allow air to be blown onto the upper face F2 of the elementary panel 1G. Thus, the metal chips generated during machining are blown away from the pressure elements 5 so as to avoid any local excess thickness that could affect the positioning of the elementary panel 1G or degrade the reference frame. Preferably, each upper blowing element 61 is located between the machining tool 4 and the pressure element 5 to prevent machining chips from coming into contact with the pressure element 5.

[0072] Similarly, still with reference to the figure 3 The machining device 2 also includes two lower blowing elements 62, specifically, one lower blowing element 62 located upstream of the machining tool 4 and one lower blowing element 62 located downstream of the machining tool 4. The lower blowing elements 62 allow air to be blown onto the lower face F1 of the elementary panel 1G. Thus, the metal chips generated during machining are blown away from the guide elements 3 so as to avoid any local excess thickness that could affect the positioning of the elementary panel 1G or degrade the reference frame. Preferably, each lower blowing element 62 is located between the machining tool 4 and the guide element 3 to prevent machining chips from coming into contact with the guide element 3.

[0073] Such blowing devices 61, 62 also prevent marking of the elementary panel 1G by machining chips.

[0074] Preferably, machining chips are collected by suction. For this purpose, with reference to the figure 4 The machining device 2 includes a dust extraction unit 64, located near the machining tool 4, to extract the chips. The upper blower elements 61 are inclined towards the machining tool 4 to facilitate central extraction by the dust extraction unit 64. This protects the horizontal reference direction Xr during machining to prevent deviation and ensure precise machining.

[0075] Preferably, as illustrated in the figure 3 The machining device 2 also includes two sweeping elements 63, specifically, an upstream sweeping element 63 located upstream of the machining tool 4 and a downstream sweeping element 63 located downstream of the machining tool 4. The sweeping elements 63 are aligned along the horizontal reference direction Xr. In this example, each sweeping element 63 is configured to sweep the lower face F1 and the upper face F2 of the elementary panel 1G. However, it is understood that a sweeping element 63 could sweep only one face of the elementary panel 1G. Thus, the metal chips generated during machining are swept away so as not to come into contact with the pressure elements 5 and the guide elements 3, thereby preventing any local excess material that could affect the orientation of the horizontal reference direction Xr.Thus, the horizontal reference direction Xr is protected during machining to prevent any deviation and ensure precision machining.

[0076] Optionally, the machining device 2 includes one or more probes for measuring the thickness of the elementary panel 1G, 1D after machining of its end, in order to perform quality control. A laser-type measuring probe is preferred.

[0077] Preferably, the machining device 2 is mounted on a functional unit 120 of the machining and welding system 100 presented in the figure 2 . The displacement device 110 is connected to the mobile base 21 of the chassis 20 of the machining device 2 and allows it to be moved, in particular along a substantially straight line so as to follow the end to be machined of the elementary panel 1G.

[0078] With reference to the figure 11 A top view is shown of a left elementary panel 1G and a right elementary panel 1D whose coating 11 is to be machined (decladding operation). In this implementation, the machining device 2 is moved along the left elementary panel 1G, then the machining device 2 is rotated 180° before being moved along the right elementary panel 1D.

[0079] The machining process for the left-hand elementary panel 1G will henceforth be presented with reference to figures 9 et 10 .

[0080] Like a sewing machine, the left-hand panel 1G moves relative to the machining device 2 when the functional unit 120 is moved by the displacement device 110. The end of the left-hand panel 1G is centered by the global alignment elements 71, and then the guiding elements 3 and the pressure elements 5 locally constrain the left-hand panel 1G so that its end is locally flat between the two constraint zones. Due to its small thickness, this plastic deformation does not affect the left-hand panel 1G even if it has one or more curves.

[0081] The end of the left elementary panel 1G is kept close to the area to be machined which extends in cantilever in order to allow space for the machining tool 4.

[0082] Unlike prior art, it is not necessary to know the absolute position of the left-hand panel 1G; the machining device 2 advantageously follows the end of the left-hand panel 1G to ensure precise positioning. Indeed, the guide elements 3 and the pressure elements 5 define, in pairs, two reference positions along the horizontal reference direction Xr, thus perfectly controlling the position of the left-hand panel 1. As the machining tool 4 is positioned between these two reference positions, its position is defined with great precision, guaranteeing high-precision machining.

[0083] The machining tool 4 is driven in rotation, and the machining device 2 is moved at a feed rate of between 150 and 800 mm / min. As the machining device 2 moves, the coating 11 of the left-hand panel 1 is precisely removed. Machining chips are blown, swept, and / or vacuumed away to avoid disrupting the machining process or the positioning of the left-hand panel 1G between the two reference positions, thus ensuring high accuracy. Depending on the shape of the machining tool 4, the lower face F1, the upper face F2, and / or the lateral face of the end of the left-hand panel 1G are machined to prepare it for friction stir welding.

[0084] As illustrated in the figure 11 , once the left elementary panel 1G is decluttered, the clamping jaws 22 of the mobile base 21 are loosened in order to change the orientation of the machining device 2 which can then machine the right elementary panel 1D in a manner analogous to the left elementary panel 1G.

[0085] After machining the two panels 1G, 1D, the machining device 2 is disconnected from the functional unit 120 and replaced by a friction stir welding device 140 as illustrated in the figure 12 The 130G and 130D support devices are adjusted to butt the ends of the 1G and 1D elementary panels together as illustrated in the figure 12 Then, the friction stir welding device 140 is activated and moved by the displacement device 110 to the interface between the elementary panels 1G, 1D so as to weld them together optimally. The elementary panels 1G, 1D are connected by a weld bead 12 as illustrated in the figure 13 .

[0086] It goes without saying that the machining and welding system 100 could also include several functional units 120 so as to have simultaneously the machining device 2 and the friction stir welding device 140.

[0087] Thanks to the machining and welding system 100 according to the invention, the elementary panels 1G, 1D are machined conveniently with high precision. Furthermore, the integration of a machining device 2 and a welding device 140 into the same system allows for high productivity while minimizing the number of handling operations required for the elementary panels.

[0088] Eliminating repetitive contact measurement steps saves significant time while increasing reliability and reducing costs.

Claims

1. Device (2) for the machining of an end of an elementary panel (1G, 1D) for the purpose of its subsequent friction stir welding, the elementary panel (1G, 1D) comprising a metal body (10) defining two opposite faces (F1, F2), the machining device (2) comprising: - a chassis (20), - at least two guiding members (3), mounted on the chassis (20) and aligned along a horizontal reference direction (Xr), each guide member (3) being fixed with respect to the horizontal reference direction (XR), the guiding members (3) being configured to guide a first face (F1) of the elementary panel (1G, 1D), - at least one machining tool (4) mounted on the chassis (20), the machining tool (4) being positioned between the two guiding members (3) with respect to the horizontal reference direction (Xr) and to a vertical position determined with respect to the horizontal reference direction (Xr) in order to remove a thickness of at least one face (F1, F2) of the elementary panel (1G, 1D), and - at least one pressure member (5) mounted on the chassis (20) and configured to exert a pressure on a second face (F2) of the elementary panel (1G, 1D) so as to press the elementary panel (1G, 1D) against the guiding members (3) along the horizontal reference direction (Xr), only the chassis (20) being configured to be moved during machining, the relative position of the tool of machining (4) with respect to the guide members (3) being defined in such a way determined and precise, the chassis (20) comprising a lower part (20A) on which are mounted the guide members (3) and an upper part (20B) on which the machining tool (4) is mounted, the vertical distance between the part lower (20A) and the upper part (20B) being adjustable.

2. Machining device (2) according to claim 1, comprising two pressure members (5), each pressure member (5) being mounted symmetrically to a guiding member (3) with respect to the horizontal reference direction (Xr), so as to sandwich the elementary panel (1G, 1D).

3. Machining device (2) according to one of the claims 1 to 2, comprising at least one blowing member (61, 62) configured to evacuate the machining chips away from the guiding (3) and / or pressure (5) members.

4. Machining device (2) according to one of the claims 1 to 3, comprising at least one sweeping member (63) configured to sweep at least one face (F1, F2) of the elementary panel (1G, 1D).

5. Machining device (2) according to one of the claims 1 to 4 wherein the chassis (20) comprises a mobile base (21) configured to enable the rotation of the machining device (2) about a vertical axis (Z).

6. Machining device (2) according to one of the claims 1 to 5, wherein the guiding members (3) are spaced along the horizontal direction by a distance d3 ranging from 60mm to 150mm.

7. System (100) for machining and welding an end of an elementary panel (1G, 1D), the machining and welding system (100) comprising at least one device (130G, 130D) for supporting at least one elementary panel (1G, 1D), a device (110) for displacing a functional unit (120) with respect to the support device (130G, 130D) and a machining device (2) according to claims 1 to 6, the machining device (2) being connected to the functional unit (120) to enable the removal of a thickness from at least one face of an elementary panel (1G, 1D) mounted on a support device (130G, 130D).

8. Machining and welding system (100) according to the preceding claim, comprising two support devices (130G, 130D) and a friction stir welding device (140) connected to the functional unit (120) so as to enable the friction stir welding of the ends of the elementary panels (1G, 1D) mounted on the support devices (130G, 130D).

9. Process for machining an end of an elementary panel (1G, 1D) for its subsequent friction stir welding by means of a machining device (2) according to one of the claims 1 to 6, the elementary panel (1G, 1D) comprising a metal body (10) defining two opposite faces (F1, F2), the first face (F1) of the elementary panel (1G, 1D) bearing against the guiding members (3), the process comprising: - A step whereby pressure is exerted by the pressure member (5) on the second face (F2) of the elementary panel (1G, 1D) so as to press the elementary panel (1G, 1D) against the guiding members (3) along the horizontal reference direction (Xr), - A step whereby the machining tool (4) is rotationally driven about a vertical axis (Z), - A step whereby the chassis (20) of the machining device (2) is moved with respect to the elementary panel (1G, 1D) in the horizontal reference direction (Xr) so as to remove a thickness from at least one face (F1, F2) of the elementary panel (1G, 1D).

10. Machining process according to claim 9, wherein at least one face of the elementary panel (1G, 1D) is covered with a cladding (11) and the machining device (2) is moved with respect to the elementary panel (1G, 1D) in the horizontal reference direction (Xr) so as to machine the cladding (11).

11. Machining process according to one of the claims 9 and 10, the process comprising a friction stir welding step of two elementary panes (1G, 1D) after machining operations.