Tooling and process for manufacturing perforated elements such as thrust reverser grids for aircraft nacelles

Abstract

The invention relates to a tool (10) for manufacturing an air deflection grid for an aircraft nacelle thrust reversal system, the grid comprising a plurality of spars, each spar being connected to at least one adjacent spar by a plurality of redirection vanes, the tool comprising: at least one molding bar (12); at least one molding column (14) of a row of vanes, comprising two opposite lateral faces extending along the longitudinal direction of the tool (10), and comprising molding cavities (140);the tooling (10) comprising a fixed structure (16) on which the molding bar (12) and the molding column (14) are mounted, the fixed structure (16) allowing a translational movement, along a transverse direction (T) of the tooling (10), of the molding bar (12), the tooling (10) comprising a compression device (18) to ensure the compression of elements (100, 110) of composite material arranged in the tooling (10) and intended to form at least a part of the grid to be manufactured. Figure 5.;

Description

Title of the invention: Tooling and method for manufacturing openwork elements such as thrust reverser grids for aircraft nacelle Technical field

[0001] The present invention relates to a tool for manufacturing openwork elements such as air deflection grilles for a thrust reversal system for an aircraft nacelle, and also relates to a method for manufacturing a grille using such a tool. Prior art

[0002] Aircraft are known which are powered by at least one propulsion unit comprising a double-flow turbojet engine housed in a nacelle. Each propulsion unit is attached to the aircraft by a mast generally located under or on a wing, or at the level of the fuselage of the aircraft.

[0003] A nacelle generally has a tubular structure comprising an air inlet upstream of the turbojet engine, a middle section intended to surround a fan of the turbojet engine, a downstream section intended to surround the combustion chamber of the turbojet engine, and is generally terminated by an ejection nozzle whose outlet is located downstream of the turbojet engine.

[0004] The downstream section incorporates in certain cases a thrust reverser system, or thrust reverser. The role of a thrust reverser is to improve the braking capacity of the aircraft by redirecting forward at least part of the thrust generated by the turbojet engine. To this end, the thrust reverser diverts at least part of the cold flow and / or the hot flow generated by the turbojet engine, thereby generating a counter-thrust which is added to the braking of the aircraft wheels. Among the various thrust reverser systems, systems comprising deflection grilles, also called cascades, are known. Such grille systems comprise one or more movable cowls which can be moved between, on the one hand, a deployed position in which they open a passage in the nacelle intended for the diverted flow, and on the other hand, a retracted position in which they close this passage.When the movable cowl(s) are in the deployed position, they uncover the deflection grilles. In addition, a system of connecting rods connects each movable cowl to blocking doors which deploy inside the secondary vein and block the direct flow outlet. The airflow is then forced to escape from the nacelle by passing through the deflection grilles, which redirect this flow towards the front of the aircraft.

[0005] An air deflection grille comprises rows of deflection vanes, each row of blades being arranged between two adjacent spars extending in a longitudinal direction of the grid. Within each row, the blades extend in a direction substantially perpendicular to those of the spars.

[0006] The grilles are advantageously made of composite materials, in order to make them lighter than metal grilles. Such grilles are generally manufactured by a process of manually draping many pieces of composite fabric, which is very expensive and does not allow truly scalable aerodynamic profiles to be obtained.

[0007] Application WO 2021 / 123628 discloses a method for manufacturing composite material grids using a tool using a plurality of fusible mobile cores, making it possible to produce the grids by compressing the composite material between the cores, using mobile compression devices. However, this method has the disadvantage of requiring a large number of cores (generally several dozen). This results in manufacturing, handling and positioning operations for these cores which are numerous and costly. Furthermore, the accumulation of positioning tolerances of the different cores generates significant dimensional variability in the grids obtained. This dimensional variability penalizes the aerodynamic performance of the grids.Furthermore, the operations of draping the blades individually also generate a significant number of preform production operations, and operations of precise positioning of these preforms on complex-shaped tools.

[0008] The objective of the present invention is to propose a tool and a method for manufacturing openwork elements made of composite material, such as thrust reverser grids for aircraft nacelle, which is less expensive than known tools and methods, and which makes it possible to produce reverser grids having geometries adapted to the aerodynamic performance of the nacelle, all in a rapid manner. Presentation of the invention

[0009] To this end, the invention relates to a tool for manufacturing an air deflection grid for an aircraft nacelle thrust reversal system, the grid comprising a plurality of spars extending in a longitudinal direction, each spar being connected to at least one adjacent spar by a plurality of redirection vanes, the tool comprising: - at least one molding bar, extending in a longitudinal direction of the tooling; - at least one column for molding a row of blades, comprising two opposite lateral faces extending in the longitudinal direction of the tooling, and comprising molding cavities, each cavity opening out on each of two side faces of the molding column, and forming an imprint for molding a blade; - the tool comprising a fixed structure on which the molding bar and the molding column are mounted, the fixed structure allowing a translational movement, in a transverse direction of the tool, of the molding bar, the tool comprising at least one compression device to ensure the movement of the molding bar towards the molding column and the compression of elements of a composite material arranged in the tool and intended to form at least part of the grid to be manufactured.

[0010] Thus, the tooling according to the invention makes it possible to produce all of the blades connecting two adjacent spars in a single molding operation, by finishing the material in the molding cavities. Furthermore, by providing a molding column comprising all of the molding cavities of blades of a row of blades, the dimensional tolerances are significantly reduced compared to a tooling requiring the installation of numerous independent mobile cores.

[0011] The tooling is simple and inexpensive. The arrangement of material is facilitated in particular thanks to the organization of the tooling with independent molding columns. It makes it possible to produce deflection grids having geometries adapted to the desired aerodynamic performances, since each row of blades is produced by means of a single molding column.

[0012] Furthermore, such a tool makes it possible to apply strong pressures to the material intended to form at least part of the grid to ensure its spreading and distribution within the parts of the tool forming the molding impression, and in particular in the molding cavities.

[0013] According to other characteristics of the invention, the tooling of the invention comprises one or more of the following optional characteristics considered alone or in all possible combinations.

[0014] According to one characteristic, the tooling comprises at least two adjacent molding columns, each molding column being mounted to move in translation, in a transverse direction of the tooling, on the fixed structure of the tooling, the tooling further comprising a second molding bar, the two molding bars being arranged on either side of the assembly formed by the molding columns.

[0015] According to one characteristic, the second molding bar is mounted to move in translation, in a transverse direction of the tool, the tool comprising a second compression device making it possible to ensure the movement of the second molding bar.

[0016] According to one characteristic, the second molding bar is fixed relative to the fixed structure.

[0017] According to one characteristic, each molding column can be placed alternately in a fixed configuration, in which it is fixed relative to the fixed structure of the tool, and in a mobile configuration, in which it is mobile in translation, in a transverse direction of the tool, relative to the fixed structure.

[0018] According to one characteristic, the or each molding column comprises between 8 and 16 cavities.

[0019] According to one characteristic, the or each molding column is produced by assembling at least two sub-assemblies, each sub-assembly comprising for example between 4 and 8 cavities.

[0020] According to one characteristic, the tooling comprises between 4 and 8 molding columns.

[0021] According to one characteristic, the or each molding column is produced in a fusible material.

[0022] According to one characteristic, the tooling comprises a guidance system, comprising for example rails, ensuring the guidance of the mobile elements of the tooling in their movement.

[0023] According to one characteristic, the or each molding column of the tooling comprises a flange molding cavity, making it possible to produce a part of one end of the grid such as a flange for fixing the grid.

[0024] The invention also relates to a method for manufacturing a thrust reverser grid for an aircraft nacelle, by compression molding in a tool as described above, the tool comprising as many molding columns as the grid to be manufactured has rows of blades and comprising two molding bars, the method comprising the following steps: - a step of arranging elements made of composite material, during which at least one first element intended to form at least in part a spar of the grid, and second elements are arranged on either side of each molding column, each second element being intended to form at least in part a blade of the grid and being arranged opposite a respective cavity of a molding column; - a compression step, during which a force is applied to at least one of the molding bars, so as to allow the assembly of the molding columns and the molding bars to come together, and so as to allow the composite material elements to be compressed sufficiently so that each second element fits into the respective cavity; - a consolidation stage, during which the composite material elements partially or completely harden; and

[0025]

[0026]

[0027]

[0028]

[0029] - a step of demolding the grid thus formed. The invention also relates to a method for manufacturing a thrust reverser grid for an aircraft nacelle, by compression molding in a tool as described above, the tool comprising as many molding columns as the grid to be manufactured has rows of blades and comprising two molding bars, the method comprising the following steps: - a step of arranging elements made of composite material, during which at least one first element intended to form at least in part a spar of the grid and second elements are arranged on one side of a molding column, each second element being intended to form at least in part a blade of the grid and being arranged opposite a respective cavity of the molding column; - a compression step, during which a force is applied to at least one of the molding bars, so as to allow the molding bar and the adjacent molding column, or two adjacent columns, to come together, and so as to allow sufficient compression of the composite material elements so that each second element forms in the respective cavity: - a consolidation stage, during which the composite material elements partially or completely harden; - the steps of material arrangement, compression and consolidation being repeated successively for each adjacent column, so as to add each time at least one spar and at least one row of blades to the part being manufactured, until the latter comprises all the spars and rows of blades of the grid to be manufactured; - A step of unmolding the grid thus formed. The methods described above make it possible to manufacture thrust reverser grids for aircraft nacelle having geometries adapted to the desired aerodynamic performances, thanks to a simpler and less expensive method than the methods of the prior art. According to other characteristics of the invention, each of the methods in accordance with the invention may comprise one or more of the following optional characteristics, considered alone or in all possible combinations. According to one characteristic, for each of the above processes, the demolding step may include the elimination of the molding columns, in particular by total or partial melting of each molding column. According to one characteristic, the composite material elements comprise a pre-impregnated composite material, comprising fibers and resin.

[0030] According to another characteristic, the elements made of composite material comprise a fibrous structure free of resin.

[0031] According to this characteristic, during the compression step, a resin in liquid form is introduced in order to impregnate the fibrous structure.

[0032] According to another characteristic, the composite material elements comprise a pre-impregnated composite material, and during the compression step, additional resin is introduced in liquid form in order to impregnate the composite material elements.

[0033] According to one characteristic, the compression step is carried out until a compression of the material intended to form at least in part the openwork element is obtained between 5 and 70%.

[0034] According to one characteristic, the method(s) comprise(s) a heating step during which the tool is heated to soften the material intended to form at least part of the openwork element, prior to the compression step. Brief description of the drawings

[0035] [Fig-1] [Fig. 1] is a perspective view of an aircraft propulsion unit, comprising a turbojet engine and a nacelle carrying a grid thrust reverser system, the thrust reverser system being shown in a deployed configuration.

[0036] [Fig.2] [Fig.2] is a partial perspective view of the thrust reverser system of the propulsion unit of [Fig.l], showing several deflection grids.

[0037] [Fig.3] [Fig.3] is a schematic view of a tool according to the invention, shown before the implementation of a compression step.

[0038] [Fig.4] [Fig.4] represents the tooling of [Fig.3], after the implementation of a compression step.

[0039] [Fig.5] [Fig.5] is a schematic view of a tool according to the invention comprising several molding columns, before the implementation of a compression step.

[0040] [Fig.6] [Fig.6] represents the tooling of [Fig.5], after the implementation of a compression step.

[0041] [Fig.7] [Fig.7] is a partial schematic view of a tool according to the invention comprising several molding columns, and allowing sequential use of the molding columns.

[0042] [Fig.8] [Fig.8] represents the tooling of [Fig.7], with an alternative arrangement of the material intended to form the openwork element.

[0043] [Fig.9] [Fig.9] is a partial schematic view of a molding column illustrating examples of placement of the material intended to form the element openwork.

[0044] [Fig. 10] [Fig. 10] is a partial schematic view of a molding column illustrating examples of placement of the material intended to form the openwork element.

[0045] [Fig. 11] [Fig. 11] is a schematic view showing a molding column comprising several subassemblies.

[0046] [Fig. 12] [Fig. 12] is a schematic view of two adjacent casting columns.

[0047] [Fig. 13] [Fig. 13] is a perspective view illustrating the two casting columns of [Fig. 12].

[0048] [Fig. 14] [Fig. 14] is a diagram illustrating the steps of a first method according to the invention.

[0049] [Fig. 15] [Fig. 15] is a diagram illustrating the steps of a second method according to the invention.

[0050] [Fig. 1] represents an aircraft propulsion unit 1 comprising a dual-flow turbojet 2, and a nacelle 3 carrying a thrust reverser system 4 with deflection grilles. The thrust reverser system 4 comprises in particular a movable external structure 4a, comprising in the example two movable cowls. The external structure 4a is movable between a closed position, in which the thrust reverser system 4 is inactive, and an open position, in which the thrust reverser system 4 is active. In the deployed position, the external structure 4a uncovers a set of deflection grilles 5, through which the redirected air escapes from the nacelle 3. Grilles 5 are better visible in the detail view of [Fig. 2].Each grid 5 comprises longitudinal members 50, elongated in a longitudinal direction of the grid 5, and deflection vanes 52 (or redirection vanes), each deflection vane 52 joining two adjacent longitudinal members 50. The vanes 52 extend between two adjacent longitudinal members in a direction substantially perpendicular to the longitudinal direction of the grid 5. Such grids 5 are advantageously made of a composite material, for example a material comprising a reinforcement comprising carbon fibers and a matrix comprising a resin. The tooling and methods described below are particularly suitable for the manufacture of openwork elements such as the grids 5 of FIGS. 1 and 2.

[0051] [Fig. 3] illustrates an exemplary embodiment of a tool 10 in accordance with the invention, making it possible to manufacture openwork elements such as the grids 5. As visible in [Fig. 3], the tool 10 comprises at least one molding bar 12 for a spar and at least one molding column 14 for blades, these elements being seen in section.

[0052] The molding bar 12 is intended for molding one of the side members 50 forming the grid 5 and extends in a longitudinal direction L of the tool 10.

[0053] The molding column 14 is intended for the simultaneous molding of several blades 52 joining two adjacent side members 50 of the grid 5. For this purpose, it comprises a plurality of molding cavities 140, each cavity 140 forming an imprint intended to form a blade 52 of the grid 5. The cavities 140 are arranged along the longitudinal direction of the tool 10 and pass through the molding column 14 in a transverse direction of the tool 10. Thus, each cavity 140 opens on either side of the molding column 14, at the level of opposite lateral faces 141, 142 thereof.

[0054] The tool 10 is configured to allow relative movement of the molding bar 12 and the molding column 14 in a transverse direction T of the tool 10. For this purpose, at least one of these two elements is movable in translation along the transverse direction T of the tool 10, relative to a fixed structure 16 of the tool 10. In the example, the fixed structure 16 comprises rails 160. The molding bar 12 and / or the molding column 14 are mounted movable in translation on the rails 160. The tool 10 further comprises a compression device 18 making it possible to ensure the relative movement of the molding bar 12 and the molding column 14, so as to bring these two elements together. In the example of figures 3 and 4, the molding column 14 is fixed relative to the fixed structure 16, while the molding bar 12 is movable relative to this structure, and in particular movable in translation along the rails 160.

[0055] The tool 10 shown in Figures 3 and 4 makes it possible to mold a part of the grid 5, this part comprising at least one spar 50 and at least one part of the blades 52 connected to this spar 50.

[0056] As can be seen in [Fig. 3], a first element 100 comprising a material intended to form at least in part the spar 50 has been arranged between the molding bar 12 and the molding column 14. On this first element 100, a second element 110 has been arranged, opposite each cavity 140 of the molding column 14, comprising a material intended to form at least in part a blade 52, by finishing in the corresponding cavity 140.

[0057] As visible in [Fig. 4], after compression of the first and second elements 100, 110 by means of the compression device 18, the assembly of the second elements 110 has flowed into the cavities 140. Thus, each second element 110 has taken the complementary shape of the corresponding cavity 140, that is to say the shape of one of the blades 52 of the grid 5. After consolidation, the molded assembly visible in [Fig. 4] can be secured to another spar manufactured or in the process of being manufactured according to the same process.

[0058] Figures 5 and 6 show an example of tooling 10 comprising two bars of molding 12 and two molding columns 14. Each of the two molding bars 12 and the two molding columns 14 is movable in translation, in the transverse direction T of the tool 10, relative to the fixed structure 16. The molding bars 12 are arranged on either side of the two molding columns 12. The tool 10 comprises two compression devices 18 arranged in an antagonistic manner, each compression device 18 making it possible to cause the movement of a respective molding bar 12. Alternatively, a single compression device 18 may be provided configured to move one of the molding bars 12, the other molding bar 12 being fixed relative to the fixed structure of the tool.

[0059] The tooling 10 of Figures 5 and 6 allows the simultaneous production, in a molding operation, of two adjacent rows of blades 52, by implementing the finishing of the material of the second elements 110 within the cavities 140 as described previously. This operation makes it possible to produce the spar 50 separating the two rows of blades, and also to produce all or part of the two spars framing these two rows. As visible in [Fig. 5], the material initially arranged in the tooling 10 comprises three first elements 100, each of which comprises a material intended to form at least in part a spar, and comprises, on either side of each molding column 14, second elements 110, intended to form at least in part the blades. After compression, a subassembly is obtained, as visible in [Fig. 6], comprising three spars and two rows of blades.This subassembly can then be secured to another subassembly, obtained in a similar manner. In the example of Figures 5 and 6, second elements 110 are arranged on either side of each molding column 14. Thus, during compression, the second elements 110 located opposite the same molding cavity 140 will flow into this cavity until they join together to form the corresponding blade together, as visible in [Fig. 6]. Alternatively, it may be provided that second elements 110 are arranged on only one side of each molding column, the second elements 110 being similar to those shown in Figures 3 and 4, and therefore configured to flow into each respective cavity 140 so as to entirely form the corresponding blade.

[0060] As a variant, the tool 10 shown in Figures 5 and 6 may comprise more than two molding columns 14 arranged between the two molding bars 12, for example between 3 and 8 molding columns 14. Thus, the tool 10 may comprise a number of molding columns 14 making it possible to produce an entire grid 5 in a single molding operation, the grid obtained comprising for example between 3 and 8 rows of blades.

[0061] [Fig.7] shows a tool 10 for producing a grid 5 sequentially. The tool 10 comprises an identical number of molding columns 14 to the number of rows of blades of the grid to be manufactured, for example between 3 and 8 molding columns 14 (three columns being shown in [Fig.7]). The tool 10 here comprises two molding bars 12 arranged on either side of the assembly formed by the molding columns 14. One of the molding bars 12 is mobile and capable of being moved by the compression device 18, while the second molding bar 12 is fixed relative to the fixed structure 16 of the tool 10. Each molding column 14 has two configurations: - a first configuration, or mobile configuration, in which the molding column 14 is mobile relative to the fixed structure 16 of the tooling; and - a second configuration, or fixed configuration, in which the molding column 14 is fixed relative to the fixed structure 16 of the tooling 10.

[0062] Each column 14 can be placed alternately in one or the other of these two configurations, independently of the other molding columns 14.

[0063] The tooling 10 can be implemented sequentially, that is to say that the molding columns 14 are used successively, one by one, to form a row of blades at each new molding operation. Thus, a first molding operation will be implemented to produce or consolidate a first spar 50 (that is to say the outer spar located at the level of the movable molding bar 12), and the first row of blades 52 adjacent to this first spar 50, by means of the first molding column 14 (the one adjacent to the movable molding bar). During this first molding operation, the first molding column 14 is in the fixed configuration, in which it is fixed relative to the fixed structure 16, so as to allow the compression of the material during the movement of the movable molding bar 12.

[0064] During a second molding operation, the subassembly formed by the first spar 50 and the first row of blades 52 is secured to the adjacent spar, at the same time as the second row of blades is formed using the second molding column 14, adjacent to the first molding column 14. During this second molding operation, the second molding column 14 is in a fixed configuration, while the first molding column 14 is in a mobile configuration, so as to be moved with the mobile molding bar 12 during the compression of the material.

[0065] At each new molding operation, the next adjacent molding column 14 is used, up to the last molding column 14, the one adjacent to the second molding bar 12 which makes it possible to produce the last spar 50.

[0066] During each molding operation, the formation of the blades is carried out in such a way that the material flowing into the cavities 140 can flow to the outside of each corresponding cavity 140 and form a projecting element 112 (as visible in [Fig.4]), all of the projecting elements 112 then being secured to the adjacent spar during the following molding operation.

[0067] Like the tooling of [Fig.6], the tooling 10 of [Fig.7] can also be implemented simultaneously (non-sequentially), that is to say so as to produce an entire grid 5 in a single molding operation. Thus, all of the spars 50 and the blades 52 of the grid 5 are formed in a single molding operation. In this case, all of the material intended to form the grid 5, including the first elements 100 and the second elements 110, is arranged in the tooling 10, (between two adjacent molding columns 14, or between one of the molding bars 12 and the adjacent molding column). All of the molding columns 14 are in the mobile configuration. Then, all of the material intended to form the grid 5 is compressed, by moving the mobile molding bar 12.Alternatively, the two molding bars 12 may be movable, and compression is achieved by moving the two molding bars 12 toward each other.

[0068] The sequential implementation described above in relation to [Fig. 7] can be carried out in a different manner. Indeed, as visible in [Fig. 8], it can be provided that during the first molding step, the fine material in the cavities 140 of the first molding column 14 so as to form only a part of each blade, for example approximately half of the blade. In this case, during the second molding step, a part of the material arranged between the first and second molding columns 14 will flow into the cavities of the first molding column 14 so as to finish all of the blades, while a second part of this material will flow into the cavities of the second column, so as to partially fill them, in a manner similar to the first molding step.This way of producing a complete blade by means of two second elements 110 flowing in opposite directions and joining within the corresponding cavity 140 can also be used in the context of the simultaneous implementation described above. In this case, the arrangement of the second elements 110 is analogous to that described in relation to [Fig.5].

[0069] Figures 9 and 10 show different ways of arranging the material intended to flow into the cavities 140, so as to facilitate finishing to obtain optimal filling of each cavity 140. In these two figures, a first element 100 is provided intended to form at least in part a spar, and three examples of arrangement of a second element 110, intended to form at least in part a blade.

[0070] In [Fig.9], a first example of arrangement of the second element 110 consists of providing folds 110a, making it possible to obtain a shape of the second element facilitating its penetration into a cavity 140 of a molding column 14. A second example of arrangement of the second element 110 consists of producing a stack 110b of folds of different sizes, so that the surface area of ​​the folds decreases as one moves away from the first element 100. Such an arrangement also promotes the penetration of the second element into the corresponding cavity 140. A third example of arrangement of the second element 110 consists of creating a stack of folds and performing a laceration 110c of this assembly opposite the corresponding cavity 140. Such an arrangement significantly promotes the penetration of the second element 110 into the corresponding cavity 140.

[0071] In [Fig. 10], a fourth example of arrangement of the second element 110 consists of providing a second element 110 which is configured to be previously fully inserted into the corresponding cavity 140, with portions protruding on either side of the cavity 140. A fifth example of arrangement of the second element 110 consists of implementing a second element 110 which is configured to be partially inserted into the corresponding cavity 140. A sixth example of arrangement of the second element 110 consists of providing an element whose shape favors its penetration into the corresponding cavity, for example a conical, pyramidal, hemispherical shape, etc.

[0072] Whatever the embodiment of the tool 10 considered, the molding columns 14 are rigid and are configured to be removable in order to allow the demolding of the openwork element to be manufactured.

[0073] Alternatively, the molding columns 14 are rigid and made at least partially from a fusible material, so as to be eliminated by melting, as will be described later. For this purpose, they can be made from a low-melting point metal alloy, with a melting point higher than the temperature sufficient to consolidate by thermocompression the perforated elements to be manufactured. In another alternative or additional variant, all or part of the molding columns 14 is soluble. For this purpose, the molding columns 14 are made from a material that is not soluble with the material of the perforated elements to be manufactured but soluble by a solvent compatible with the material of the perforated elements to be manufactured once the latter has been sufficiently consolidated.

[0074] Advantageously, as visible in [Fig.l 1], a molding column 14 can advantageously be produced by assembling several sub-assemblies 144, each sub-assembly 144 comprising several cavities 140. In the example, a molding column 14 comprising twelve molding cavities 140 is produced by assembling three sub-assemblies 144 each comprising four cavities 140. In order to produce a precise assembly, the sub-assemblies 144 can comprise at one and / or the other of their ends a shape 144a, 144b complementary to that of the corresponding end of the adjacent sub-assembly.

[0075] Advantageously, as seen in Figures 12 and 13, the molding columns 14 may comprise positioning elements 146, 148 making it possible to ensure precise positioning between two adjacent molding columns 14 during a compacting step bringing these two molding columns 14 together. In the example of FIGS. 12 and 13, the positioning elements 146, 148 comprise a first sole 146, or lower sole, and a second sole 148, or upper sole, the soles 146, 148 extending along the longitudinal direction of the tooling 10, and being offset in the transverse direction of the tooling, in an identical manner for each molding column 14. This configuration makes it possible to achieve precise positioning by nesting the adjacent molding columns together.

[0076] Advantageously, the or each molding column 14 of the tool 10 comprises a flange molding cavity (not shown), making it possible to produce, by finishing in said cavity, a part of a fixing flange of the grid 5.

[0077] Figures 14 and 15 represent the steps of implementing methods in accordance with the invention, these methods using tooling 10 in accordance with the invention.

[0078] [Fig. 14] represents the steps of implementing a method 200 for manufacturing a grid 5, using tooling 10 similar to that of FIGS. 5 and 6, and comprising as many molding columns 14 as the grid 5 to be manufactured has rows of blades 52.

[0079] This method 200 comprises a step 202 of arranging material 100, 110 intended to form at least in part the grid 5, during which there are arranged, on either side of each molding column 14, at least one first element 100 intended to form at least in part a spar 50 of the grid 5, and second elements 110, each second element 110 being intended to form at least in part a blade of the grid 5 and being arranged opposite a respective cavity 140 of a molding column 14.

[0080] The method 200 comprises a compression step 204, during which a force F is applied to at least one of the molding bars 12, so as to allow the assembly of the molding columns 14 and the molding bars 12 to come together, and thus the compression of the material intended to form at least part of the grid 5. The compression step 204 is carried out by means of the compression device(s) 18.

[0081] The method 200 comprises a consolidation step 206, during which the material intended to form at least part of the grid 5 hardens partially or completely.

[0082] The method 200 comprises a step 208 of demolding the grid thus formed.

[0083] [Fig. 15] represents the steps of implementing a manufacturing method 201 of a grid 5, using a tool 10 similar to that of figures 7 and 8, and comprising as many molding columns 14 as the grid 5 to be manufactured comprises 52 rows of blades.

[0084] The method 201 comprises a step 203 of arranging material 100, 110 intended to form at least in part the grid 5, during which there are arranged, on one side of a molding column 14, at least one first element 100 intended to form at least in part a spar 50 of the grid 5, and second elements 110, each second element 110 being intended to form at least in part a blade 52 of the grid and being arranged opposite a respective cavity 140 of the molding column 14.

[0085] The method 201 comprises a compression step 205, during which a force F is applied to at least one of the molding bars 12, so as to allow the molding bar 12 and the molding column 14 to come together, and thus the compression of the material intended to form at least part of the grid 5.

[0086] The method 201 comprises a consolidation step 207, during which the material intended to form at least part of the grid 5 hardens partially or completely.

[0087] The steps 201, 203, 205 of material arrangement, compression and consolidation are repeated successively for each following adjacent column, so as to add each time at least one spar and at least one row of blades to the part being manufactured, until the latter comprises all the spars and rows of blades of the grid to be manufactured.

[0088] The method 201, like the method 200, then comprises a step 208 of demolding the grid thus formed.

[0089] The demolding step 208 may comprise, for one and / or the other of the methods 200, 201, the elimination of the molding columns 14, in particular by total or partial melting of each molding column 14.

[0090] Preferably, the composite material constituting the various elements to be molded, including the first elements 100 and the second elements 110, is a pre-impregnated composite material. It comprises, for example, a thermosetting or thermoplastic resin and fibers, such as carbon fibers.

[0091] The resin of the pre-impregnated composite material may be raw, or partially or totally crosslinked. In particular, the resin contained in the first element 100 may be partially crosslinked, so that this element is partially consolidated before being secured to the second elements 110, during the step of forming the corresponding row of blades.

[0092] The pre-impregnated composite material advantageously comprises continuous fibers and / or discontinuous fibers, such as carbon, glass, aramid, nylon or polyester fibers.

[0093] During each compression and / or consolidation step, an optional heating step can be implemented, in particular in order to soften the resin of the material. prepreg composites.

[0094] The consolidation or hardening of the final part is obtained by maintaining the temperature and then cooling it according to the values ​​and durations adapted to the resin used. A thrust reverser grid 5 for the nacelle is then obtained by demolding the consolidated composite material and extracting the tooling elements. Finishing and machining operations can also be carried out.

[0095] In the case where the casting columns are partially or entirely made of low-melting point metal alloy, a heating step at a temperature higher than the melting temperature of the alloy is carried out after consolidation of the resin.

[0096] In one embodiment, the heating step is carried out where appropriate after the cooling mentioned above.

Claims

Claims

1. Tooling (10) for manufacturing an air deflection grid (5) for an aircraft nacelle thrust reversal system, the grid (5) comprising a plurality of spars (50) extending in a longitudinal direction, each spar (50) being connected to at least one adjacent spar by a plurality of redirection vanes (52), the tooling comprising: - at least one molding bar (12), extending in a longitudinal direction (L) of the tooling (10); - at least one molding column (14) for a row of blades, comprising two opposite lateral faces (141, 142) extending in the longitudinal direction of the tool (10), and comprising molding cavities (140), each cavity (140) opening onto each of two lateral faces (141, 142) of the molding column (14), and forming an imprint for molding a blade (52);the tool (10) comprising a fixed structure (16) on which the molding bar (12) and the molding column (14) are mounted, the fixed structure (16) allowing a translational movement, in a transverse direction (T) of the tool (10), of the molding bar (12), the tool (10) comprising at least one compression device (18) to ensure the movement of the molding bar (12) towards the molding column (14) and the compression of elements (100, 110) made of composite material arranged in the tool (10) and intended to form at least part of the grid to be manufactured.;

2. Tooling (10) according to the preceding claim, comprising at least two adjacent molding columns (14), each molding column (14) being mounted to move in translation, in a transverse direction (T) of the tooling (10), on the fixed structure (16) of the tooling, the tooling (10) further comprising a second molding bar (12), the two molding bars (12) being arranged on either side of the assembly formed by the molding columns (14).

3. Tooling (10) according to the preceding claim, in which the second molding bar (12) is mounted to move in translation, in a transverse direction of the tooling, the tooling (10) comprising a second compression device (18) allowing the movement of the second molding bar (12).

4. Tooling (10) according to claim 2, wherein the second molding bar (12) is fixed relative to the fixed structure (16).

5. Tooling (10) according to one of claims 2 to 4, in which each molding column (14) can be placed alternately in a fixed configuration, in which it is fixed relative to the fixed structure (16) of the tooling (10), and in a mobile configuration, in which it is mobile in translation, in a transverse direction (T) of the tooling, relative to the fixed structure (16).

6. Tooling (10) according to one of the preceding claims, in which the or each molding column (14) comprises between 8 and 16 cavities.

7. Tooling (10) according to the preceding claim, in which the or each molding column (14) is produced by assembling at least two sub-assemblies (144), each sub-assembly comprising for example between 4 and 8 cavities.

8. Tooling (10) according to one of the preceding claims, comprising between 4 and 8 molding columns (14).

9. Tooling (10) according to one of the preceding claims, in which the or each molding column (14) is made of a fusible material.

10. Tool (10) according to any one of the preceding claims, comprising a guidance system, comprising for example rails (160), ensuring the guidance of the mobile elements of the tool (10) in their movement.

11. Method (200) for manufacturing a thrust reverser grid (5) for an aircraft nacelle, by compression molding in a tool (10) according to any one of the preceding claims, the tool (10) comprising as many molding columns (14) as the grid (5) to be manufactured comprises rows of blades (52) and comprising two molding bars (12), the method comprising the following steps: - a step (202) of arranging elements (100, 110) made of composite material, during which at least one first element (100) intended to form at least in part a spar of the grid and second elements (110) are arranged on either side of each molding column, each second element (110) being intended to form at least in part a blade of the grid and being arranged opposite a respective cavity (140) of a molding column (14); - a compression step (204), during which a force (F) is applied to at least one of the molding bars (12), so as to allow the assembly of the molding columns (14) and the molding bars (12) to come together, and so as to allow the compression of the elements (100, 110) made of composite material sufficient for each second element (110) to fit into the respective cavity (140); - a consolidation step (206), during which the composite material elements partially or completely harden; and - a step (208) of demolding the grid thus formed.

12. Method (201) for manufacturing a thrust reverser grid (5) for an aircraft nacelle, by compression molding in a tool (10) according to any one of claims 1 to 10, the tool (10) comprising as many molding columns (14) as the grid (5) to be manufactured has rows of blades (52) and comprising two molding bars (12), the method (201) comprising the following steps: - a step (203) of arranging elements (100, 110) made of composite material, during which at least one first element (100) intended to form at least in part a spar (50) of the grid (5) and second elements (110) are arranged on one side of a molding column (14), each second element (110) being intended to form at least in part a blade (52) of the grid (5) and being arranged opposite a respective cavity (140) of the molding column (14); - a compression step (205), during which a force (F) is applied to at least one of the molding bars (12), so as to allow the molding bar (12) and the adjacent molding column (14) to come together, or two adjacent molding columns (14), and so as to allow sufficient compression of the elements (100, 110) made of composite material so that each second element (110) thin in the respective cavity (140); - a consolidation step (207), during which the elements (100, 110) made of composite material harden partially or completely; - the steps (203, 205, 207) of material arrangement, compression and consolidation being repeated successively for each adjacent column (14), so as to add each time at least one spar (50) and at least one row of blades (52) to the part being manufactured, until the latter comprises all the spars (50) and rows of blades (52) of the grid (5) to be manufactured; - A step (208) of demolding the grid thus formed.

13. Method (200, 201) according to claim 11 or 12, in which the demolding step (208) comprises the elimination of the molding columns (14), in particular by total or partial melting of each molding column.

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