Tool for pressing down a ply of material such as a prepreg, and associated pressing method

Abstract

The invention relates to a pressing-down tool (100) comprising a holder (10) and at least one pressure-bagging membrane (20) secured to the holder (10), the pressure-bagging membrane (20) being inflatable by a fluid and configured such that for a predetermined pressure applied by the fluid-inflated pressure-bagging membrane (20) to a surface (S) that is to be pressed down, the pressure-bagging membrane (20) deforms to ensure surface contact forming a bearing surface (S'), of a surface-area comprised within a predetermined surface-area range, in which the pressure-bagging membrane (20) bears against the surface (S) that is to be pressed down.

Description

DESCRIPTION TOOL FOR MAROUFLING A PLIE OF MATERIAL SUCH AS A PREPREG AND ASSOCIATED MAROUFLING METHOD TECHNICAL FIELD OF THE INVENTION

[0001] The invention relates, in general, to the technical field of composite ply draping.

[0002] The invention relates more specifically to a marouflage tool, in particular for marouflage of at least one ply of material such as a prepreg intended to form at least part of a composite part, and an associated marouflage method. STATE OF PRIOR ART

[0003] As is well known from the prior art, a composite material part can be made from a fibrous reinforcement pre-impregnated with resin. Such fibrous reinforcements can be, for example, made of carbon, aramid, or composed of any other material suitable depending on the desired use of the part. The resin can be of different types such as an epoxy or polyester resin or the like.

[0004] In a first phase called draping, plies pre-impregnated with fiber reinforcement are placed on a counterform to form a preliminary part called a preform or blank. During this lamination, it is usual to use a "de-bubbling roller", also called a "marouflage tool", to expel the air from the laminate to make the layers of fiber reinforcement homogeneous with each other. The preliminary part can then be pre-consolidated under vacuum in an optional step called compaction. In such a compaction step, the ply is pressed against the mold or counterform using negative pressure.

[0005] In a next phase, called dressing, the preliminary part is placed on a tool. During this step, the preliminary part is covered with a stack of films (called dressing) whose functions differ depending on the desired part. The dressing can include several films such as a fabric to be delaminated, generally placed only on the preliminary part, a waterproof film, a trailing fabric to cover the waterproof film and / or a tarpaulin forming a bladder in order to ensure the waterproofing of the covering.

[0006] During a third phase, called polymerization, the dressed preliminary part is placed in a vacuum chamber and subjected to a temperature and pressure cycle in order to be consolidated and obtain a part called a raw part in composite material. After polymerization, the raw part is demolded and checked (defects, surface condition and dimensions).

[0007] Today, the smearing tools used in the field of composite lay-up are vectorial, meaning they move along an axis. This is the case, for example, when a tool has the shape of a roller. Such shapes are advantageous in that they have large contact surfaces allowing a relatively large surface area of ​​prepreg plies to be smeared.

[0008] Depending on their configuration, however, these tools cannot rotate or change trajectory without the risk of shearing the material and potentially damaging it.

[0009] Furthermore, to apply positive or negative angles and / or point supports, point support type tools with the appropriate shape are also necessary. This generally requires the use of several different tools, specifically adapted to predetermined areas.

[0010] As a result, the marouflage stage often has low efficiency, particularly due to the return paths avoiding shearing of the material and tool changes.

[0011] Following the use of these tools, a global vacuum is carried out via a tarpaulin and a drainage environment. In addition to expelling the air from the laminate to make the layers of fiber reinforcement homogeneous with each other, the marouflage step helps to limit the appearance of folds in the fiber reinforcement plies, which will generate precision deviations during draping and local excess thicknesses in the material that would be frozen during this vacuum. STATEMENT OF THE INVENTION

[0012] The invention aims to remedy all or part of the drawbacks of the state of the art by proposing in particular a solution making it possible to avoid a purely vectorial movement of the tool and which can be adapted to complex draping surface profiles.

[0013] To do this, according to a first aspect of the invention, a marouflage tool is proposed comprising a support and at least one marouflage cushion secured to the support, the marouflage cushion being inflatable by a fluid and configured so that for a predetermined pressure of the marouflage cushion inflated with fluid on a surface to be marouflaged, the marouflage cushion deforms to guarantee surface contact forming a support surface with an area included in a predetermined area range of the marouflage cushion against the surface to be marouflaged.

[0014] Thanks to such a combination of characteristics, a marouflage tool is obtained that can deform according to the shape of the surface against which it moves and move along this surface.

[0015] According to one embodiment, the marouflage tool comprises: a fluid inlet opening into an interior space of the marouflage cushion and connected to a first connection interface configured to be connected to an external fluid network; and a fluid outlet opening open into the interior space of the marouflage cushion and connected to a second connection interface configured to be connected to the external fluid network; such that the inflatable marouflage cushion is capable of being crossed by the fluid circulating from the inlet to the outlet, preferably continuously.

[0016] According to one embodiment, the marouflage tool comprises gripping means configured to engage an element to be marouflaged, the gripping means preferably comprising suction cups.

[0017] According to one embodiment, the marouflage cushion is arranged at least partly between the support and the gripping means, and in that the marouflage cushion marouflage is inflatable between two states, a deflated state and a fluid-inflated state, the marouflage tool being configured so that in a gripping position of an element to be marouflaged and in the deflated state, the marouflage cushion does not apply a force to the element to be marouflaged, while in a fluid-inflated state, the marouflage cushion applies a force to the element to be marouflaged greater than a retaining force applied by the gripping means to said element to be marouflaged.

[0018] According to one embodiment, the marouflage tool comprises at least a portion of heating means for heating the fluid inside the cushion, the means for heating the fluid comprising, for example, sources of infrared radiation, for example located in the marouflage cushion. Such heating means integrated into the marouflage tool make it possible to improve the performance of the bonding of the fabrics of the pre-impregnated ply during marouflage and to increase the tackiness of the fabrics.

[0019] According to one embodiment, walls of the marouflage cushion have a variable thickness, preferably these walls are thicker at the level of the side walls and thinner at the level of a wall distal to the support and intended to form all or part of the support surface of the marouflage cushion to come against the surface to be marouflaged, the side walls of the marouflage cushion at least partly surrounding the distal wall.

[0020] According to one embodiment, the marouflage tool comprises a secondary marouflage tool, at least partly housed in the marouflage cushion, the secondary marouflage tool comprising for example at least one roller or a spatula.

[0021] According to one embodiment, the inflatable marouflage cushion is composed of a polymer material, for example plastic or silicone.

[0022] According to one embodiment, the predetermined area range is bounded below by a minimum area of ​​900 mm 2 .

[0023] According to one embodiment, the predetermined area range is bounded above by a maximum area of ​​2.25 m 2 .

[0024] According to another aspect of the invention, it relates to a robot arm, for example for a cobot, remarkable in that it comprises a marouflage tool as described above.

[0025] According to another aspect, the invention also relates to a marouflage robot comprising a robot arm provided with a marouflage tool as described above and control means for controlling the movement of the robot arm.

[0026] According to one embodiment, the marouflage robot comprises a fluid network for ensuring the circulation of fluid in the marouflage cushion from the inlet to the fluid outlet of said marouflage cushion, the fluid network being controlled at least in part by the control means of the robot arm.

[0027] According to one embodiment, the marouflage robot comprises at least a portion of heating means for heating the fluid inside the cushion, the heating means being remote from the marouflage tool, more preferably remote from the robot arm.

[0028] In one embodiment, the fluid is air. In another embodiment, the fluid may be oil. Generally, any fluid having a boiling point that does not exceed a predetermined maximum operating temperature that is linked to a maximum acceptable temperature before polymerization may be preferred. Preferably, this temperature should not exceed 50 degrees. In one embodiment, the fluid has a boiling point less than or equal to 50° Celsius.

[0029] According to another aspect, the invention relates to a method of marouflage a surface to be marouflaged by a marouflage tool as described above, the marouflage method being remarkable in that the marouflage cushion is inflated by the fluid and in that the marouflage cushion is moved over the surface to be marouflaged while maintaining a contact interface between the marouflage cushion and the surface to be marouflaged.

[0030] According to one embodiment, the marouflage method is implemented by a marouflage robot as described above.

[0031] According to one embodiment, the marouflage method comprises: an initial step of inflating the marouflage cushion to a predetermined average internal pressure strictly lower than a maximum internal pressure of the marouflage cushion; a step of positioning the marouflage cushion against the surface to be marouflaged to apply a predetermined force against the surface to be marouflaged; a step of moving the marouflage cushion along the surface to be marouflaged.

[0032] According to one embodiment, the marouflage method comprises, concomitantly with the step of moving the marouflage cushion along the surface to be marouflaged, a step of varying the internal pressure of the marouflage cushion.

[0033] According to one embodiment, the marouflage tool is moved over the surface to be marouflaged along a trajectory having at least one curved portion.

[0034] According to one embodiment, the marouflage tool is moved over the surface to be marouflaged by sliding the inflatable marouflage cushion over the surface to be marouflaged.

[0035] According to one embodiment, the step of positioning the marouflage pad against the surface to be marouflaged to apply a predetermined force against the surface to be marouflaged may be a step of moving the tool by the robot so as to move the marouflage pad towards and against the surface to be marouflaged.

[0036] According to one embodiment, the marouflage tool comprises gripping means configured to engage with an element to be marouflaged, the marouflage method comprising, preferably prior to the initial inflation step of the marouflage cushion, a step of gripping an element to be marouflaged by the gripping means.

[0037] According to one embodiment, the marouflage method comprises, preferably prior to the step of moving the marouflage cushion along the surface to be marouflaged, a step of inflating the marouflage cushion at least until the marouflage cushion applies a force to the element to be marouflaged greater than a retaining force applied by the gripping means to said element to be marouflaged so as to separate the element to be marouflaged from the gripping means.

[0038] According to one embodiment, the marouflage tool comprises a secondary marouflage tool at least partly housed in the marouflage cushion, preferably housed entirely in the marouflage cushion, the marouflage method comprising a step of marouflage of the surface to be marouflaged by the secondary marouflage tool.

[0039] According to one embodiment, the step of marouflage of the surface to be marouflaged by the secondary marouflage tool comprises a step of moving the secondary marouflage tool along the surface to be marouflaged, the secondary tool housed in the cushion applying a force on the element to be marouflaged through the wall of the cushion preferably greater than or equal to the force applied by the marouflage cushion on the element to be marouflaged.

[0040] According to one embodiment, the step of marouflage of the surface to be marouflaged by the secondary marouflage tool can be implemented independently of the movement of the pad during marouflage by said pad. In other words, the step of marouflage of the surface to be marouflaged by the secondary marouflage tool can be implemented whether the marouflage pad moves along the surface to be marouflaged or whether the pad is static against the surface to be marouflaged.

[0041] According to one embodiment, the step of marouflage of the surface to be marouflaged by the secondary marouflage tool is implemented when the force applied by the marouflage cushion on the element to be marouflaged has a value greater than or equal to a predetermined threshold value. BRIEF DESCRIPTION OF THE FIGURES

[0042] Other characteristics and advantages of the invention will emerge from reading the description which follows, with reference to the appended figures, which illustrate: figure 1: a view of a cobot equipped with a marouflage tool according to one embodiment; figure 2: an isometric perspective view from above of a marouflage tool according to one embodiment; figure 3: an isometric perspective view from below of the marouflage tool according to the embodiment of figure 2; figure 4: a side view of the marouflage tool according to the embodiment of figure 2; figure 5: a side view of the marouflage tool according to the embodiment of figure 2, in a slightly inflated state of a marouflage cushion; figure 6: a side view of the marouflage tool according to the embodiment of figure 2, in an inflated state of the marouflage cushion;Figure 7: a side view of the marouflage tool according to the embodiment of Figure 2, approaching a surface to be marouflaged; Figure 8: a side view of the marouflage tool according to the embodiment of Figure 2, in contact with a surface to be marouflaged; Figure 9: a perspective view of the marouflage tool according to the embodiment of Figure 2, in contact with the surface to be marouflaged; Figure 10: a partial side sectional view of the marouflage tool according to the embodiment of Figure 2, in an inflated state of the cushion; of marouflage and including a secondary marouflage tool housed in the marouflage cushion.

[0043] For clarity, identical or similar elements are identified by identical reference signs throughout the figures. DETAILED DESCRIPTION OF AN EMBODIMENT

[0044] Figure 1 illustrates a view of a robot 1, in particular here a cobot equipped with an arm 2 of robot 1. In other words, this embodiment is a so-called “collaborative” robot 1, that is to say working in a shared space and configured to interact with a person. The cobot is generally dependent on the movements of the operator. In the context of an application to an automated production line for example, several cobots are likely to intervene jointly with human operators, or in the immediate vicinity of said operators.

[0045] The robot 1 has, at a distal end of its articulated arm 2, an interface configured to ensure the attachment of a marouflage tool 100. Its characteristics, in particular dimensional characteristics, may vary depending on the shape and dimensions of the tools 100 to be gripped.

[0046] The marouflage tool 100 also has an interface to ensure its attachment to the arm 2 of the robot 1.

[0047] The marouflage tool 100 is composed in particular of a support 10 oriented axially along a reference axis A, a proximal face or rear face of which is oriented towards the distal end of the articulated arm 2 and a distal face or front face oriented forward or towards a surface to be marouflaged S (see FIG. 5), on the side axially opposite the rear side. The interface of the marouflage tool 100 is located on the rear side 10A of the support 10. The assembly interface of the marouflage tool 100 to the arm 2 of the robot 1 is configured so that in the assembled position of the marouflage tool 100 on the arm 2 of the robot 1 as illustrated in FIG. 1, the reference axis A is coaxial with a reference axis of a reference end portion 2' of the articulated arm 2 of the robot 1.

[0048] The function of the marouflage tool 100 is to marouflage surfaces, for example pre-impregnated plies. The use of relatively wide tools 100 such as rollers are used so as to be able to extend in particular along a dimension in the plane of the surface to be marouflaged sufficiently wide to be able, during its movement against the surface to be marouflaged, to cover the entire extent of an average air bubble caught in the pre-impregnated ply. Another advantage of covering with the tool 100, a dimension in the plane of the surface to be marouflaged sufficiently wide is to be able to cover a relatively large surface to be marouflaged S and thus gain in efficiency and yield. However, such rollers do not allow a complex movement due to their shape which limits the gestures, but also due to the fact that such movements risk shearing the material and potentially damaging it.

[0049] In the context of the present invention and against popular belief, the marouflage tool 100 is provided with a marouflage cushion 20 secured to the support 10, the marouflage cushion 20 being inflatable by a fluid. In this case, the fluid used is air. The pneumatic cushion 20 is placed on the front face side of the support 10 so that it can be placed against the surface S to be marouflaged. The marouflage cushion 20 is configured to deform and ensure surface contact forming a bearing surface S' of the marouflage cushion 20 against the surface S to be marouflaged.

[0050] The marouflage cushion 20 comprises walls 22 delimiting an envelope defining an interior space 21 of the marouflage cushion 20 and configured to accommodate the fluid. The walls 22 of the cushion 20 are fluid-tight. In particular, the marouflage cushion 20 comprises at least one distal wall 22B which is the wall intended to come against the surface to be marouflaged S to form all or part of the bearing surface S' of the cushion 20. On the axially opposite side of the cushion 20 to this distal wall 22B, the marouflage cushion 20 comprises a proximal wall directly facing the support 10 and intended to be fixed to said support 10. These proximal and distal walls 22B are connected to each other by at least one lateral wall 22A of the cushion 20. The lateral walls 22A of the marouflage cushion therefore surround the distal wall 22B by bordering it. The proximal, distal 22B and lateral 22A walls together delimit the interior space 21 of the cushions 20.

[0051] In an inflated state of the marouflage cushion 20 and distant from the surface to be marouflaged S, free of constraints, that is to say without contact with the surface to be marouflaged and without pressure exerted by an external element on the marouflage cushion 20, the proximal and distal walls 22B of the cushion 20 extend in a generally parallel manner relative to each other and each in a plane oriented in a generally perpendicular manner relative to the reference axis A.

[0052] In a particular configuration, the walls 22 of the marouflage cushion 20 have different thicknesses so that the thickness of the walls 22 of the cushion 20 varies depending on its location. In particular, the walls 22 are thicker at the side walls 22A and thinner at the distal wall 22B. In the illustrated embodiment, the side walls 22A have a thickness of between 5 and 8 mm while the distal wall 22B which is front has a thickness of between 0.5 and 8 mm.

[0053] Generally, each side wall 22A has a thickness greater than or equal to 3 mm, more preferably greater than or equal to 5 mm, and / or greater than or equal to 10 mm, more preferably greater than or equal to 8 mm. Preferably in addition, or alternatively, the distal wall 22B has a thickness greater than or equal to 0.5 mm, more preferably greater than or equal to 1 mm, and / or greater than or equal to 3 mm, more preferably greater than or equal to 2 mm.

[0054] Such a configuration where the proximal and distal walls 22B of the cushion 20 are thinner than the side wall 22A where the thickness is reinforced in particular by a greater thickness, makes it possible to facilitate the passage of the inflatable cushion 20 along the variable geometry of the surface to be marouflaged S while maintaining maximum contact with it, and therefore guaranteeing the largest possible support surface S' of the cushion 20 during its movement despite a non-zero gradient of the topography of the surface to be marouflaged S.

[0055] The marouflage cushion 20 thus has a flexibility allowing it to locally match the shape of the surface to be marouflaged S. This flexibility makes it possible to guarantee that for a predetermined pressure of the marouflage cushion 20 inflated by fluid on the surface S to be marouflaged, the marouflage cushion 20 deforms to guarantee a surface contact forming the support surface S' with an area included in a predetermined area range of the marouflage cushion 20 against the surface S to be marouflaged.

[0056] During the marouflage, the marouflage cushion 20 comes into contact and bears against the surface to be marouflaged S, the pressure exerted by the marouflage cushion 20 against the surface to be marouflaged S allowing it to slide over it when said marouflage cushion 20 is moved against it, while ensuring its marouflage function.

[0057] When carrying out a marouflage operation on a surface to be marouflaged S predetermined by such a tool 100, the marouflage cushion 20 is thus pressed against said surface to be marouflaged S: in a sufficiently strong manner to obtain a contact interface between the marouflage cushion 20 and the surface to be marouflaged S having a sufficiently large area for the marouflage to be effective and for the area of ​​the bearing surface S' to be as homogeneous and continuous as possible, but in a sufficiently weak manner so that this pressure, on the one hand, does not damage the marouflaged material, and on the other hand, does not hinder the movement of the marouflage cushion 20 against its surface.

[0058] To address these issues, an optimum predetermined area range of the support surface S' is preferably limited: below, by a minimum area of ​​900 mm 2 ; and / or higher, by a maximum area of ​​2.25 m 2 .

[0059] Indeed, too large a support surface S' would make it difficult to smooth a surface with too complex a topography and would penalize the agility of the tool 100 during its use. On the contrary, too small a support surface S' would harm the effectiveness of the smoothing and the performance of the tool 100. In practice, this surface can be predetermined in a certain way by the transverse dimension of the 20 marouflage cushion. For example, the area of ​​the surface of the distal wall 22B can be limited below, by a minimum area of ​​900 mm 2 and / or higher, by a maximum area of ​​2.25 m 2 .

[0060] In this embodiment, the inflatable masking cushion 20 is composed of a polymer material, for example plastic or silicone. The material(s) constituting the inflatable masking cushion 20 is (are) chosen so as to allow good flattening and good masking despite the presence of a relief or obstacles on the surface to be masked. These reliefs or obstacles may be, for example, stiffeners giving a complex geometry to the surface to be masked. A material sufficiently elastic to be deformed, such as silicone, for example, will make it possible to obtain an inflatable masking cushion 20 whose stretching of the walls will allow better masking efficiency despite a complex geometry of the surface to be masked.

[0061] According to one embodiment, the inflatable masking cushion 20 is made of elastomer material. The material forming the inflatable cushion 20 preferably has a hardness greater than or equal to 5 shore A, more preferably greater than or equal to 10 shore A, and / or less than or equal to 40 shore A, more preferably less than or equal to 30 shore A. Such hardness provides improved resistance for use in this field of masking while giving it flexibility for masking complex geometries by allowing the membrane of the cushion to reach the most awkward corners of the surface.

[0062] According to the invention, the masking tool 100 is configured to circulate the fluid, preferably in the form of gas, through the inflatable masking bag 20. Thus, the masking tool 100 comprises a fluid inlet 101 opening into the interior space 21 of the masking bag 20 and connected to a first connection interface 11 configured to be connected to an external fluid network 40 and a fluid outlet 102 opening into the interior space of the masking bag 20 and connected to a second connection interface 12 configured to be connected to the external fluid network 40. In this way, the inflatable bag 20 can be crossed by the fluid circulating from the inlet 101 to the outlet 102, preferably continuously. Furthermore, it is also possible to vary the internal fluid pressure in the inflatable marouflage cushion 20.

[0063] The external fluid network 40 comprises a source of fluid preferably remote from the marouflage tool 100, more preferably remote from the arm 2 of the robot 1. It can also be carried for example at the base of the cobot 1, or even remote from said cobot 1, for example in the vicinity of a control cabinet. The fluid network 40 comprises flexible fluid circulation pipes so as to be able to run along the various joints of the robot without impairing its range of action.

[0064] Thanks to such a configuration of the marouflage tool 100, the support surface S' of the inflatable cushion 20 can be modulated according to the size of the inflatable cushion and the internal pressure of filling the fluid in the interior space 21 of the marouflage cushion 20. This internal pressure of the marouflage cushion 20 depends on the fluid that it contains and which circulates within it thanks to the fluid network 40 but it can vary according to the robotic arm 2 which can apply pressure by moving the tool 100 to bring it closer, in particular its support 10, to the marouflaged surface S. In practice, the robotic arm 2 is controlled to allow support with a given force and in a second step the internal pressure of the inflatable cushion 20 is modulated by the control of the fluid network 40 in the desired direction. With the support force, if too much pressure is applied, the cushion 20 will tend to deflate to maintain the pressure.Furthermore, if too much pressure is applied to the masking cushion 20, the cushion 20 will be too rigid and therefore less able to penetrate into the defects in the part. Moderate inflation is therefore required to allow the cushion 20 to penetrate into the concavities of the mold. According to one embodiment, the masking cushion is inflated to an internal pressure greater than or equal to 2 bars, preferably greater than or equal to 4 bars and / or less than or equal to 9 bars, preferably less than or equal to 7 bars. With the materials used and the wall thicknesses defined in this embodiment, an internal pressure close to 4 bars is particularly advantageous.

[0065] The support 10 which carries the marouflage cushion 20 generally has the shape of a plate extending in a plane orthogonal to the reference axis A. In particular, and to facilitate the agility of the marouflage tool 100, the plate forming support 10 has a peripheral edge of the support delimiting a shape whose size corresponds substantially to that of the cross section of the marouflage cushion 20. This support plate 10 also makes it possible to carry the first and second connection interfaces 11, 12 which are secured to it.

[0066] During a compaction step, it is known to pre-consolidate the preliminary part under vacuum by pressing the fold against the mold from a negative pressure. Such a fabric compaction step is generally implemented by means of vacuum tarpaulins.

[0067] According to the invention, the tool 100 is provided with gripping means 30 configured to engage with the element to be marouflaged 200. These gripping means here comprise suction cups 31. These suction cups are distributed around the marouflage cushion 20 and carried by the support 10 of the tool 100.

[0068] The marouflage cushion 20 is arranged at least partly in a space located between the support 10 and the gripping means 30. In this way, the suction cups 31 do not interfere with the use of the inflatable cushion 20. The marouflage cushion 20 is inflatable between two states, namely between a deflated state and a state inflated by the fluid.

[0069] The marouflage tool 100 is configured so that in a gripping position of the element to be marouflaged 200 and in the deflated state, the marouflage cushion 20 does not apply any force to the element to be marouflaged 200 (see FIG. 5). In such a configuration, the marouflage cushion 20 is arranged entirely in the space located between the support 10 and the gripping means 30, the marouflage cushion 20 being axially set back from a hooking plane P in which the suction cups 31 are located and which is perpendicular to the reference axis A.

[0070] The marouflage tool 100 is further configured so that in a gripping position of the element to be marouflaged 200 and in a fluid-inflated state, the marouflage cushion 20 applies a force to the element to be marouflaged 200 greater than a retaining force applied by the gripping means 30 to said element to be marouflaged 200. In this configuration, the cushion 20 is inflated and its volume has increased. The gripping means 30 being fixed relative to the support 10 and the cushion 20 being integral with the support at its proximal wall 22, the inflation of the cushion 20 induces a distance of its distal wall 22B relative to its proximal wall until this distance is greater than the distance separating the attachment plane P from the support. In the gripping position of the element to be marouflaged 200 then located in the attachment plane P and in an inflated state of the cushion 20, there is therefore an interaction produced by said cushion 20 which comes into contact and bears against the element to be marouflaged 200. This position is maintained until the force exerted by the cushion 20 on the element to be marouflaged 200 becomes greater than the retaining force of the suction cups 31 fixed to the element to be marouflaged 200 (see figure 6).During the step of marouflage by the cushion 20, the gripping means 30 are inactive and the cushion 20 is in an inflated state so as to protrude axially relative to the gripping means 30. In other words, during the marouflage step in which the marouflage cushion 20 moves along the surface to be marouflaged S, the cushion 20 is inflated such that the distance between the distal wall 22B and the proximal wall is strictly greater than its proximal wall until this distance is greater than the distance separating the attachment plane P from the support 10. In such a configuration, the gripping means 30 do not hinder the progression of the cushion 20 along the surface to be marouflaged S even if it has a relief.

[0071] Such a tool 100 thus makes it possible, on the one hand, to allow the fabric forming the element to be glued 200 to be gripped by the suction cups 31 and, on the other hand, to implement a step of compacting the fabrics on the mold. These steps are distinct but carried out by the same tool 100 for gluing. Once the element to be glued 200 has been gripped in a gripping step, then at a time it comes to give the support force of the cushion 20 which makes it possible to remove the force from the suction cups 31 and to detach them in a successive pushing step.

[0072] In a particular use, it is possible to consider implementing two stages of gripping and pushing at the same time: satisfactory results are observed in practice and the maintenance of the fabric is controlled. Thanks to such a configuration, the fold can be taken by the suction cups 31 and pressed against the mold or counterform thanks to the action of the inflatable cushion 20 which allows it to be pressed onto any shape.

[0073] In an alternative or complementary embodiment, it is possible to provide gripping means housed inside the cushion 20 and / or secured to the cushion 20. For example, suction cups can be placed on the cushion 20 itself, in the manner of the suction cups placed on the arm of an octopus.

[0074] The gripping means 30 may be configured to be movable, preferably controlled by the control means. They may thus be movable between a deployed gripping position and a position retracted towards the support 10 so as not to risk hindering the marouflage by the marouflage cushion 20. The rods supporting the suction cups 31 may for example slide to move the associated suction cup 31 between a retracted position, in which it is positioned in a reference plane of the support 10 and a deployed position where it is axially distant from the support 10, on the side of the marouflage cushion 20.

[0075] Experience has shown that the efficiency of the compacting step, i.e. the bonding of the fabric to the mold, is improved depending on the duration of this operation and the temperature. For improved efficiency and for the material to adapt to the shape of the mold and remain bonded to it, the fluid inside 21 of the cushion 20 is brought to a temperature of at least 15 degrees Celsius, preferably at least 20 degrees Celsius. The circulation of a hot fluid (generally liquid or gaseous) inside the inflatable cushion 20 thus simulates a temperature close to that of the human body, usually reproduced by operators in the marouflage process at the time of shaping the fabric carried out manually.

[0076] To implement such a temperature, the tool 100 comprises at least a portion of heating means for heating the fluid inside the marouflage cushion 20, which thus improves its efficiency. The fluid heating means are located along the fluid network 40 and may be located at one or more different locations. For example, a main fluid heating means may be offset relative to the marouflage tool 100, or even offset from the arm 2 of the robot 1, and / or a secondary heating means, separate from the heating means main, can also be contained in the inflatable cushion 20, that is to say housed in the interior space 21 of the inflatable cushion 20. The continuous circulation of the fluid through the inflatable cushion 20 makes it possible to maintain a constant or almost constant temperature inside the inflatable cushion 20 and therefore to avoid any loss of heat at the level of the cushion which could take place by transfer of heat energy between the cushion 20 and the element to be marouflaged 200 when they are in contact.

[0077] An example of heating means, main or secondary, contained in the inflatable cushion 20 or outside, for example carried by the support 10, may comprise for example one or more sources of infrared radiation.

[0078] The heating means are configured so that the heat produced and supplied to the cushion is limited so as to avoid triggering a polymerization reaction of the pre-impregnated ply. Preferably, the heating means are configured to heat the fluid circulating in the cushion 20 to a temperature greater than or equal to 15 degrees Celsius, preferably greater than or equal to 25 degrees Celsius and / or less than or equal to 50 degrees Celsius, more preferably greater than or equal to 40 degrees Celsius. In this embodiment, the air in the cushion is heated to a temperature of 40 degrees Celsius. Such a temperature improves the tackiness of the pre-impregnated ply.

[0079] In an alternative or complementary embodiment, the heating means may be configured so that the heat produced and supplied to the cushion is sufficient to initiate the complete polymerization reaction. In this case, the materials constituting the marouflage tool, and in particular the cushion, must be compatible to withstand such heat. This heat may be, for example, 180 degrees Celsius.

[0080] The masking robot 1 comprises the robot arm 2 provided with the masking tool 100 and control means for controlling the movement of the robot arm 2 and the masking tool 100 itself. These same control means thus make it possible to control the circulation of fluid through the fluid network 40, and in particular in the masking cushion 20 from the inlet 101 to the outlet 102 of fluid of said marouflage cushion 20, as well as control means allowing the control of the gripping means 30 and heating.

[0081] The method of using the marouflage tool 100 will be better understood upon reading the following description.

[0082] The method of marouflage of the surface S to be marouflaged by such a marouflage tool 100 according to the invention consists in substance of inflating the marouflage cushion 20 with fluid and moving the marouflage cushion 20 over the surface S to be marouflaged while maintaining a contact interface between the marouflage cushion 20 and the surface S to be marouflaged.

[0083] During an initial step of inflating the marouflage cushion 20, the latter is inflated to a predetermined average internal pressure strictly lower than a maximum internal pressure of the marouflage cushion 20.

[0084] The marouflage pad 20 is then moved during a movement step towards and against the surface to be marouflaged S to apply a predetermined force against the surface to be marouflaged S. The marouflage pad 20 is then moved along the surface to be marouflaged S.

[0085] Concomitantly with the step of moving the marouflage cushion 20 along the surface to be marouflaged S, a step of varying the internal pressure of the marouflage cushion 20 is ensured in order to adapt the pressure according to the evolution of the relief of the surface to be marouflaged S.

[0086] During the implementation of the process, this pressure can be varied, or kept generally constant depending on the area of ​​the surface to be coated, or depending on the geometry of the surface.

[0087] The internal pressure of the marouflage cushion 20 can vary according to different parameters controlled by the robot, and more precisely by the control means. These parameters can be for example the distance separating the marouflage tool 100 from the surface to be marouflaged S, this allowing, at a constant volume of fluid in the marouflage cushion 20, to vary the internal pressure of said cushion 20. The variation in the distance between said surface to be marouflaged S and in particular the support 10 thus makes it possible to vary the support force provided by said cushion 20. Similarly, the control means can vary the speed of circulation of the fluid in the inflatable cushion 20 so as to vary its internal pressure.

[0088] During the marouflage process, the arm 2 of the robot 1 is moved after the initial step of inflating the marouflage cushion 20 towards and against the surface to be marouflaged S to apply a predetermined force against the surface to be marouflaged S.

[0089] In practice, the marouflage tool 100 presses with a given force on the surface to be marouflaged S, by means of the marouflage cushion 20 alone, and the control means make it possible to ensure management of the pressure of the inflatable cushion 20. If, with this force, the pressure of the marouflage cushion 20 on the surface to be marouflaged S is too great, the marouflage cushion 20 will tend to deflate to maintain the pressure since the flow of air circulating inside is constant. If too great a pressure were then then ensured, the marouflage cushion 20 would then inflate more before pressing and the marouflage cushion 20 would penetrate less or not at all into the defects of the part.

[0090] For this reason, and preferably, the control means ensure inflation with a relatively limited internal pressure of the masking cushion 20 so that it fits into the concavities of the mold and during masking, it is sought to maintain an internal pressure as constant as possible. According to one embodiment, the masking cushion is inflated to an internal pressure greater than or equal to 2 bars, preferably greater than or equal to 4 bars and / or less than or equal to 9 bars, preferably less than or equal to 7 bars. With the materials used and the wall thicknesses defined in this embodiment, an internal pressure close to 4 bars is particularly advantageous.

[0091] Figure 10 illustrates an embodiment which differs from those described above essentially in that the marouflage tool 100 comprises at least one secondary marouflage tool 120 at least partly housed in the marouflage cushion 20. Such a tool is indeed an active tool which provides a marouflage function, independently of the marouflage cushion 20. It is therefore not a passive structure without a marouflage function, such as a spacer mechanism which could be provided to protect the cushion from premature wear by rubbing against the secondary tool 120 or against the support 10.

[0092] According to one embodiment, such a secondary tool 120 separate from the cushion may comprise a tool chosen from at least one roller, at least one spatula (not shown) and at least one marouflage ball or ball (not shown).

[0093] In the case of a marouflage ball, the secondary tool 120 may comprise, for example, a support and a marouflage ball retained by the support of the secondary tool 120 so as to be able to rotate, the marouflage ball preferably being configured so that for a predetermined pressure of the marouflage ball on a surface to be marouflaged, the marouflage ball deforms elastically to ensure surface contact forming a bearing surface of the marouflage ball against the surface to be marouflaged. Such a tool makes it possible to obtain a reduced contact surface and multidirectional movements.

[0094] With reference to Figure 10, the secondary marouflage tool 120 comprises a roller 121 mounted on a support 123 movable on rails 124. The rails 124 are arranged on either side of the roller and each guide one end of an axis carrying the roller 121 and around which the roller 121 can rotate. Each rail 124 is integral with the support 10, the movement of the roller 121 being actuated by a jack 122 connected at a proximal end to the support 10 and at a distal end, opposite the proximal end, to the support 123. The rail 124 is configured to guide the movement of the roller actuated by the jack 122.

[0095] Generally speaking, such a secondary 120 marouflage tool equipped with a roller allows for a larger contact surface and one-way movements.

[0096] Preferably, the secondary marouflage tool 120 intervenes in a second step after the cushion 20 has pressed the fabric of the element to be marouflaged 200 onto a contact surface, for example a mold or a layer of fabric. previously laid and marouflaged. In particular, the step of marouflage of the surface to be marouflaged by the secondary marouflage tool 120 is implemented when the force applied by the marouflage pad 20 on the element to be marouflaged 200 has a value greater than or equal to a predetermined threshold value. The secondary marouflage tool 120 is particularly interesting for marouflaged the element to be marouflaged 200 on an area requiring a force greater than that of the pad as such.

[0097] During its use, a step of marouflage of the surface to be marouflaged by the marouflage cushion is implemented. Then, for a predetermined reason, in particular when the topography of the part requires applying a force on the element to be marouflaged 200 greater than or equal to a predetermined threshold value, the control means control the movement of the secondary marouflage tool 120. The secondary marouflage tool 120 is movable between a retracted position (see FIG. 10), in which it is located axially set back from the attachment plane P, to a deployed position in which it is located beyond the attachment plane to come to bear against the element to be marouflaged 200 through the wall of the cushion 20.

[0098] Actuated directly by the marouflage robot, in particular by the control means, the gripping means 30, here the suction cups 31, block or limit at least partly transversely the cushion 20 and the secondary marouflage tool 120 moves in the interior space 21 of the cushion 20 and can marouflage the places more complicated to reach with the cushion 20, in particular when the secondary marouflage tool 120 comprises a marouflage ball or ball.

[0099] The secondary marouflage tool 120 comprises actuating means such as an integrated motor and allowing the movement of the secondary marouflage tool 120 in the cushion 20. In the case of a roller 121 and for medium or small parts, this movement is generally monodirectional. In the case of a marouflage ball or ball, the movement can be multidirectional. In such a configuration, the means for moving the marouflage ball or ball are different from a simple rail and adapted to a multidirectional movement, for example a ball joint controlled by the control means, the ball joint being arranged between, preferably interposed between, the support 10 on the inner side of the cushion 20 and the support of the secondary tool 120.

[0100] The secondary marouflage tool 120 therefore intervenes in a second stage after the cushion has pressed the fabric onto the contact surface.

[0101] Generally speaking, such a marouflage tool 100 can be used in the vast majority of part cases because it is generic. It makes it possible to carry out at least two separate operations regarding picking-up using the gripping means 30 and marouflage using the marouflage cushion 20 with a single tool, improving the performance of the marouflage process in terms of time. Such a marouflage tool 100 also guarantees more uniform pressure applied to the entire contact surface, as with a vacuum tarpaulin but with the flexibility of being able to put it in place at any time. Such a marouflage tool 100 also makes it possible to improve the cycle time thanks to the possibility of varying the temperature of the fluid circulating in the marouflage cushion 20. The invention is particularly suitable for carrying out the depositing of the first ply on a mold and its marouflage.Indeed, the first ply encounters additional constraints compared to subsequent plies. Since the tackiness of the surface of a mold is much lower than that of a ply, there are greater sliding constraints. In practice, the marouflage tool according to the invention offers particularly satisfactory results, especially for marouflage of a first ply in a mold.

[0102] The tool 100 proposed in this technical solution is of the non-vector type. It can therefore perform linear, curved / circular trajectories, and serve as a point support. It also increases productivity in the sense that the tool 100 does not need to “unstick” the marouflage cushion 20 from the draping surface to be marouflaged S and to go through a phase of returning to a start of trajectory (pure movement).

[0103] Naturally, the invention is described in the foregoing by way of example. It is understood that those skilled in the art are able to carry out different variant embodiments of the invention without departing from the scope of the invention.

[0104] It is emphasized that all the characteristics, as they emerge for a person skilled in the art from the present description, the drawings and the attached claims, even if concretely they have only been described in relation to other determined characteristics, both individually and in any combinations, may be combined with other features or groups of features disclosed herein, provided that this has not been expressly excluded or that technical circumstances make such combinations impossible or meaningless.

Claims

CLAIMS 1. Marouflage tool (100) comprising a support (10) and at least one marouflage cushion (20) secured to the support (10), the marouflage cushion (20) being inflatable by a fluid and configured so that for a predetermined pressure of the marouflage cushion (20) inflated with fluid on a surface (S) to be marouflaged, the marouflage cushion (20) deforms to guarantee a surface contact forming a bearing surface (S') of area included in a predetermined area range of the marouflage cushion (20) against the surface to be marouflaged (S).

2. Marouflage tool (100) according to claim 1, characterized in that it comprises: a fluid inlet (101) opening into an interior space (21) of the marouflage cushion (20) and connected to a first connection interface (11) configured to be connected to an external fluid network (40); and a fluid outlet (102) opening into the interior space of the marouflage cushion (20) and connected to a second connection interface (12) configured to be connected to the external fluid network (40); so that the inflatable cushion (20) is capable of being crossed by the fluid circulating from the inlet (101) to the outlet (102), preferably continuously.

3. Marouflage tool (100) according to claim 1 or 2, characterized in that it comprises gripping means (30) configured to engage with an element to be marouflaged (200), the gripping means (30) preferably comprising suction cups (31).

4. Marouflage tool (100) according to claim 3, characterized in that the marouflage cushion (20) is arranged at least partly between the support (10) and the gripping means (30), and in that the marouflage cushion (20) is inflatable between two states, a deflated state and a fluid-inflated state, the marouflage tool (100) being configured so that in a gripping position of an element to be marouflaged (200) and in the deflated state, the marouflage cushion (20) does not apply force to the element to be marouflaged (200), while in a deflated state inflated with fluid, the marouflage cushion (20) applies a force to the element to be marouflaged (200) greater than a retaining force applied by the gripping means (30) to said element to be marouflaged (200).

5. Marouflage tool (100) according to any one of the preceding claims, characterized in that it comprises at least a portion of heating means for heating the fluid inside the marouflage cushion (20), the means for heating the fluid comprising, for example, sources of infrared radiation, for example located in the marouflage cushion (20).

6. Marouflage tool (100) according to any one of the preceding claims, characterized in that walls (22) of the marouflage cushion (20) have a variable thickness, preferably these walls (22) are thicker at the level of side walls (22A) and thinner at the level of a distal wall (22B) relative to the support (10) and intended to form all or part of the bearing surface (S') of the marouflage cushion (20) to come against the surface to be marouflaged (S), the side walls (22A) of the marouflage cushion at least partly surrounding the distal wall (22B).

7. Marouflage tool (100) according to any one of the preceding claims, characterized in that it comprises a secondary marouflage tool (120), at least partly housed in the marouflage cushion (20), the secondary marouflage tool (120) comprising for example at least one roller, a ball or ball, or a marouflage spatula.

8. Marouflage tool (100) according to any one of the preceding claims, characterized in that the inflatable marouflage cushion (20) is composed of a polymer material, for example plastic or silicone.

9. Marouflage tool (100) according to any one of the preceding claims, characterized in that the predetermined area range is bounded below by a minimum area of ​​900 mm 2 .

10. Marouflage tool (100) according to any one of the preceding claims, characterized in that the predetermined area range is bounded above by a maximum area of ​​2.25 m 2 .

11. Arm (2) of a robot (1), for example for a cobot, characterized in that it comprises a marouflage tool (100) according to any one of the preceding claims.

12. A masking robot (1) comprising a robot arm (2) provided with a masking tool (100) according to any one of claims 1 to 10 and control means for controlling the movement of the robot arm (2) (1).

13. Masking robot (1) according to claim 12 provided with a masking tool (100) according to at least claim 2, characterized in that it comprises a fluid network (40) to ensure the circulation of fluid in the masking cushion (20) from the inlet (101) to the fluid outlet (102) of said masking cushion (20), the fluid network (40) being controlled at least in part by the control means of the arm (2) of the robot (1).

14. A marouflage robot according to claim 12 or 13, characterized in that it comprises at least a portion of heating means for heating the fluid inside the marouflage cushion (20), the heating means being remote from the marouflage tool (100), more preferably remote from the robot arm (2) Cl)- 15. Masking robot according to any one of claims 12 to 14, characterized in that the fluid consists of air.

16. Method for marouflage a surface to be marouflaged by a marouflage tool according to any one of claims 1 to 10, the marouflage method being characterized in that the marouflage cushion (20) is inflated by the fluid and in that the marouflage cushion (20) is moved over the surface to be marouflaged (S) while maintaining a contact interface between the marouflage cushion (20) and the surface to be marouflaged (S). A method of marouflage according to claim 16, characterized in that it is implemented by a marouflage robot (1) according to any one of claims 12 to 15. A method of marouflage according to claim 16 or 17, characterized in that it comprises: an initial step of inflating the marouflage cushion (20) to a predetermined average internal pressure strictly lower than a maximum internal pressure of the marouflage cushion (20); a step of positioning the marouflage cushion (20) against the surface to be marouflaged (S) to apply a predetermined force against the surface to be marouflaged (S); a step of moving the marouflage cushion (20) along the surface to be marouflaged (S). Marouflage method according to claim 18, characterized in that it comprises, concomitantly with the step of moving the marouflage cushion (20) along the surface to be marouflaged (S), a step of varying the internal pressure of the marouflage cushion (20).A method of marouflage according to one of claims 16 to 19, characterized in that the marouflage tool (100) comprises gripping means (30) configured to engage with an element to be marouflaged (200), the marouflage method comprising a step of gripping an element to be marouflaged (200) by the gripping means (30). A method of marouflage according to claim 20, characterized in that it comprises a step of inflating the marouflage cushion (20) at least until the marouflage cushion (20) applies a force to the element to be marouflaged (200) greater than a retaining force applied by the gripping means (30) to said element to be marouflaged (200) so as to separate the element to be marouflaged (200) from the gripping means (30). A method of marouflage according to any one of claims 16 to 21, characterized in that the marouflage tool (100) comprises a secondary marouflage tool (120) at least partly housed in the marouflage cushion (20), preferably housed entirely in the marouflage cushion (20), the marouflage method comprising a step of marouflage of the surface to be marouflaged by the secondary marouflage tool (120). Marouflage method according to claim 22, characterized in that the step of marouflage of the surface to be marouflaged by the secondary marouflage tool (120) comprises a step of moving the secondary marouflage tool (120) along the surface to be marouflaged (S), the secondary tool (120) housed in the cushion (20) applying a force on the element to be marouflaged (200) through the wall of the cushion (20), preferably greater than or equal to the force applied by the marouflage cushion (20) on the element to be marouflaged (200).Marouflage method according to claim 23, characterized in that the step of marouflage of the surface to be marouflaged by the secondary marouflage tool (120) is implemented when the force applied by the marouflage cushion (20) on the element to be marouflaged (200) has a value greater than or equal to a predetermined threshold value.

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