Wing-to-wing box joint rib for an aircraft and method for manufacturing an aircraft using such rib

Abstract

The present disclosure provides a joining rib (37) designed for wing-center wing box joining in order to reduce the time and cost required for the final assembly of the aircraft, the joining rib (37) includes a main web (39) and an upper flange (16A) and a lower flange (16B), the upper flange (16A) and the lower flange (16B) extending from the main web on a first side (C1), the main web having a joining surface (24) arranged on a second side (C2) opposite to the first side, the main web including rows of openings (34) open on the first side and on the second side in the joining surface, the rows of openings (34) including a first row of openings (R1) and a third row of openings (R3) formed in an upper portion of the main web on either side of the upper flange and a second row of openings (R2) formed in a lower portion of the main web, each of the rows of openings (34) including an opening in a vacant state.

Description

Technical Field

[0001] The present invention relates to the field of aircraft structures and more specifically to a joining rib designed for a wing-to-center wing box joining of an aircraft, a method for manufacturing such a joining rib, the use of the joining rib or the method as part of a method for manufacturing a center wing module of an aircraft, the use of the method for manufacturing a center wing module of an aircraft as part of a method for manufacturing a fuselage section of an aircraft and finally the use of the method for manufacturing a fuselage section of an aircraft as part of a method for manufacturing an aircraft. Background Art

[0002] In an aircraft comprising a fuselage and wings, the wings comprising two opposite symmetrical wings fastened to the fuselage, the fuselage generally comprises a box-shaped structure called a "central wing box", to which are fastened corresponding structures of the wings, also formed as boxes and generally called "lateral wing boxes".

[0003] The center wing box generally includes an upper panel, a lower panel, and front and rear members, the upper panel is also called a dome panel, the lower panel is also called a soffit panel, and each of the front and rear members connects the lower panel to the upper panel. The center wing box generally includes an inner reinforcing rib connecting the lower and upper panels and the front and rear members together.

[0004] The junction of each wing with the fuselage is provided by junction ribs which act as structural interfaces between the respective lateral wing box and the central wing box.

[0005] The joining ribs usually comprise a core and a set of cross-shaped or T-shaped profile elements which are located at the periphery of the core and fastened to the core by means of shear bolts, as shown, for example, on page 283 of the publication Airframe Structural Design (1988) by Michael Chun-Yung Niu.

[0006] Each of the profile elements comprises a flange fastened to a corresponding panel or member of the central wing box together with one or more corner fittings, and another flange fastened to a corresponding panel or member of a lateral wing box together with one or more other corner fittings. The flanges and fittings are usually fastened to the panels and members by means of shear bolts.

[0007] The configuration of these elements (ribs and profile elements) is such that most of the mounting and fastening operations of these elements take place during preliminary stages of the aircraft assembly process, and in particular during the final assembly phase during the fastening of the wing to the fuselage.

[0008] Currently, the final assembly phase is a particularly expensive phase in the overall process of assembling an aircraft. Summary of the invention

[0009] A specific object of the present invention is to provide a simple, economical and effective solution to this problem.

[0010] To this end, the invention proposes a joining rib intended for a wing-central wing box joint of an aircraft, comprising a central web and upper and lower flanges extending from the main web on a first side relative to the main web.

[0011] The main web has a joining surface arranged on a second side opposite to the first side, and the main web includes rows of apertures open on the first side and on the second side in the joining surface, the rows of apertures including at least a first row of apertures formed in an upper portion of the main web and extending from a front side to a rear side of the joining rib, and a second row of apertures formed in a lower portion of the main web and extending from a front side to a rear side of the joining rib, each row of apertures including apertures in an empty state.

[0012] "Upper portion" and "lower portion" mean that the upper portion extends generally above the lower portion.

[0013] An “opening in a free state” means that the opening is not occupied, that is to say can subsequently accommodate a fastening component.

[0014] A joining rib made in this way enables the wing to be joined to a portion of the aircraft fuselage in a particularly simple and effective manner, thereby making it possible in particular to minimize the number and complexity of the remaining operations to be carried out at the final assembly stage of the aircraft, as will be more clearly presented below.

[0015] Furthermore, the rows of apertures include a third row of apertures formed in the upper portion of the main web and extending from the front side to the rear side of the engagement rib, so that the first and third rows of apertures are arranged on either side of the upper flange, respectively. The third row of apertures also includes apertures in an empty state.

[0016] The main web is therefore able to directly absorb the tensioning forces of the upper fitting, as will appear more clearly below.

[0017] The engaging rib preferably comprises an extension portion which is inclined with respect to the engaging surface and which extends from an upper end portion of the upper part of the main web on the second side to form an obtuse angle with the upper flange in cross section.

[0018] The joining rib preferably also includes a front flange and a rear flange, which extend from the main web on a first side relative to the main web, and the rows of holes also include a fourth row of holes formed in the front portion of the main web and extending from the lower side to the upper side of the joining rib and a fifth row of holes formed in the rear portion of the main web and extending from the lower side to the upper side of the joining rib.

[0019] The present invention also relates to a method for producing a joining rib of the above type, the method comprising at least the following steps:

[0020] a) providing a core and a profile element, each of which comprises a respective base and a respective flange extending so as to protrude from the base; then

[0021] b) fastening the respective base of the profile element to the core such that the respective flange of the profile element extends on a first side relative to the core in correspondence with said first side, the core and the respective base of the profile element together forming said main web;

[0022] And wherein, at the end of the process, the main web comprises rows of apertures, said rows of apertures comprising at least said first row of apertures formed in the base of a first profile element of the profile element, called the upper profile element, and said second row of apertures formed in the base of a second profile element of the profile element, called the lower profile element, the upper and lower profile elements being arranged at two opposite ends of the core, called the upper end and the lower end, so that the base of the upper profile element forms said upper part of the main web and the flange of the upper profile element forms said upper flange, and so that the base of the lower profile element forms said lower part of the main web and the flange of the lower profile element forms said lower flange, the base of the upper profile element extending on either side of the flange of the upper profile element and comprising a third row of apertures, and each row of apertures comprising apertures in a vacant state.

[0023] Each of the profile elements except the upper profile piece preferably also has an angled configuration.

[0024] The process preferably also includes the following steps:

[0025] c) providing first corner fittings referred to as inner frame supports, the inner frame supports each comprising a respective base and a shoulder;

[0026] d) After step b), fastening the respective bases of the inner frame supports to the main webs.

[0027] Where applicable, the row of openings also advantageously comprises a fourth row of openings formed in a third profile element, referred to as the front profile element, and a fifth row of openings formed in a fourth profile element, referred to as the rear profile element, the front profile element and the rear profile element being arranged at two opposite ends of the core, referred to as the front end and the rear end, each of the front end and the rear end connecting the upper end of the core to the lower end, such that the base of the front profile element forms the front portion of the main web and the flange of the front profile element forms the front flange, and such that the base of the rear profile element forms the rear portion of the main web and the flange of the rear profile element forms the rear flange.

[0028] The invention also relates to a method for manufacturing a central wing module for an aircraft, the method comprising the following steps:

[0029] A) producing at least one engaging rib of the above-described type, potentially by means of a method of the above-described type;

[0030] B) providing at least one second corner fitting, referred to as an upper outer fitting, comprising a base and a shoulder;

[0031] C) providing at least one strip;

[0032] D) providing a central wing box, the central wing box comprising at least an upper panel, a lower panel, a front member and a rear member, the front member connecting the front end of the upper panel to the front end of the lower panel, and the rear member connecting the rear end of the upper panel to the rear end of the lower panel, so that the upper and lower panels and the front and rear members define an interior space of the central wing box, the interior space being open at at least one lateral end of the central wing box; and then

[0033] E) arranging the engagement ribs at said lateral ends of the central wing box by inserting the flanges into the inner space of the central wing box so that the upper flanges face the upper panel and the lower flanges face the lower panel; and then

[0034] F) fastening the upper flange and the base of the at least one upper exterior fitting together to the upper panel using a first through-mount fastening component, and fastening the lower flange and the proximal portion of the at least one strap together to the lower panel using a second through-mount fastening component, such that the distal portion of the at least one strap extends beyond the engagement surface in a direction away from the center wing box.

[0035] Where applicable, step F) advantageously also comprises fastening the front flange and the rear flange to the front member and the rear member respectively.

[0036] The distal portion of the at least one strap is preferably angled in cross-section relative to the proximal portion of the at least one strap.

[0037] Where applicable, the shoulder of the at least one upper outer fitting advantageously comprises orifices respectively aligned with orifices of the third row of orifices.

[0038] The invention also relates to a method for producing a fuselage section for an aircraft, the method comprising at least the following steps:

[0039] i) Manufacturing a central wing module for an aircraft according to a method of the above type;

[0040] ii) Provide fuselage structural parts;

[0041] iii) fastening the at least one upper exterior fitting to the fuselage structure.

[0042] In a preferred embodiment:

[0043] The fuselage structure comprises circumferential frames provided with respective third corner fittings called outer frame supports, the outer frame supports each comprising a respective base and a respective shoulder; and

[0044] Step iii) comprises fastening respective shoulders of the outer frame support to respective shoulders of the inner frame support using a third through-mount fastening member.

[0045] In a preferred embodiment, the fuselage structure comprises a skin and step iii) comprises fastening the skin to the extension using a fourth through-mount fastening member.

[0046] The invention also relates to a method for manufacturing an aircraft, the method comprising at least the following steps:

[0047] I) manufacturing a fuselage section according to a method of the above type;

[0048] II) providing at least one wing, the at least one wing comprising a lateral wing box defining an interior space; then

[0049] III) positioning one end of the lateral wing box to face the engagement surface so that a distal end portion of the at least one strip is positioned outside the inner space of the lateral wing box; and then

[0050] IV) fastening the lateral wing box to the engagement rib using fastening means operating under tension / compression respectively engaging in the apertures of said row of apertures and fastening the lateral wing box to the distal portion of said at least one strap using fifth through-mounted fastening means.

[0051] Preferably:

[0052] - the lateral wing box comprises an upper panel and a lower panel and at least one fourth corner fitting and at least one fifth corner fitting;

[0053] - said at least one fourth corner fitting and said at least one fifth corner fitting each comprise a respective base and a shoulder;

[0054] - the base of the at least one fourth corner fitting is fastened to the upper panel of the lateral wing box within the internal space of the lateral wing box;

[0055] - the base of the at least one fifth corner fitting is fastened to the lower panel of the lateral wing box within the internal space of the lateral wing box;

[0056] - said fastening means operating under tension / compression comprises a sixth through-mounted fastening means mounted through an aperture formed in a shoulder of said at least one fourth corner fitting and an aperture in the first row of apertures; and

[0057] - said fastening means operating under tension / compression comprise a seventh through-mounted fastening means mounted through an aperture formed in the shoulder of said at least one fifth corner fitting and through an aperture in the second row of apertures.

[0058] In a preferred embodiment:

[0059] - the lateral wing box comprises at least one sixth corner fitting comprising a base and a shoulder;

[0060] - the base of the at least one sixth corner fitting is fastened to the upper panel outside the internal space of the lateral wing box; and

[0061] - said fastening means operating under tension / compression comprise an eighth through-mounted fastening means mounted through an aperture formed in the shoulder of said at least one sixth corner fitting, an aperture in the third row of apertures and an aperture in the shoulder of said at least one upper outer corner fitting. BRIEF DESCRIPTION OF THE DRAWINGS

[0062] The invention will be better understood and further details, advantages and features of the invention will emerge on reading the following description given by way of non-limiting example and with reference to the accompanying drawings, in which:

[0063] Figures 1 to 3 is a schematic perspective view of a profile element designed for producing a joining rib during successive steps of producing the profile element;

[0064] Figure 4 is a perspective schematic diagram of an element designed to be used for manufacturing a joining rib;

[0065] Figure 5 yes Figure 4 A schematic perspective view of the components of the invention being assembled to form a joint rib;

[0066] Figure 6 yes Figure 5 an enlarged view of a portion of;

[0067] Figure 7 is with Figure 5 Similar views, Figure 7 The engagement rib is shown at a subsequent stage in its manufacture;

[0068] Figure 8 yes Figure 7 an enlarged view of a portion of;

[0069] Fig. 9 is with Figure 7 A similar view but from a different angle;

[0070] Fig.10 and Fig.11 are schematic cross-sectional views and perspective views of joining ribs and other elements designed for manufacturing a central wing module;

[0071] Fig.12 It is through Fig.10 and Fig.11 A partial three-dimensional schematic diagram of a central wing module formed by assembling components;

[0072] Fig.13 and Fig.14 yes Fig.12 an enlarged view of a portion of;

[0073] Fig.15 and Fig.16 is used to include Fig.12 A partial schematic diagram of a cross section of a fuselage portion of an aircraft having a central wing module;

[0074] Fig.17 It is a partial schematic diagram of the cross section of the fuselage section and the wing;

[0075] Fig.18 is with Fig.17 Similar views, Fig.18 The wings are shown assembled on the fuselage section;

[0076] Fig.19 Yes Fig.18 A three-dimensional schematic diagram of an aircraft with wings and fuselage parts;

[0077] Fig. 20 is a flow chart of a method for manufacturing an aircraft according to a preferred embodiment of the present invention. DETAILED DESCRIPTION

[0078] Now refer to Figures 1 to 19 And always refer to Fig. 20A joining rib according to a preferred embodiment of the invention designed for a wing-to-center wing box joining of an aircraft and a method for manufacturing an aircraft according to a preferred embodiment of the invention which fully exploits the advantages obtained by said joining rib are described, wherein: Figures 1 to 19 The different steps of the process are illustrated successively, Fig. 20 An overall flow chart of the process is shown.

[0079] In the following description, directions X, Y, and Z are defined by reference to the orientation of elements within an aircraft during the manufacture of the aircraft. The longitudinal direction X is generally defined as parallel to the roll axis of the aircraft, the lateral direction Y is defined as parallel to the pitch axis of the aircraft, and the vertical direction Z is defined as parallel to the yaw axis of the aircraft.

[0080] The method for producing an aircraft first comprises a step I) which comprises producing a fuselage section.

[0081] Step I) in turn comprises step i) which comprises manufacturing a central wing module.

[0082] Step i) comprises step A), which comprises producing at least one engaging rib, and step A) will now be described in detail.

[0083] As an example, the engagement rib under consideration is designed to fit on the right hand side of an aircraft.

[0084] Reference Figure 4 , step A) comprises a first step a), which comprises providing a core 10 and a profile element 12, each of which comprises: a corresponding base 14 having a main front face 14A; and corresponding flanges 16A to 16D, which extend on the side opposite to the main front face 14A to protrude from the base 14.

[0085] Reference Figures 1 to 3 Each of the profile elements 12 can advantageously be manufactured by a method comprising forming a base 14 and a flange 16 by means of a mould 20 ( Figure 1 ) is a step of extruding the material for forming the element 12, and then forming the element 12 ( Figure 2 ) makes it possible to give the element 12 a possible step of curvature.

[0086] The configuration of the profile element 12 is very suitable for manufacture by extrusion, which allows the extrusion to be manufactured as a component at a much lower cost than the forging techniques sometimes used to manufacture cross-shaped or T-shaped profile elements of the prior art.

[0087] Furthermore, the method for prefabricating the profile element 12 may comprise the following steps: using a processing tool 22 ( Figure 3 ) machining the element 12, which potentially makes it possible to improve the surface condition of the element 12 and, where applicable, to form holes through the base 14 and possible countersinks around each hole (holes and countersinks are in Figures 1 to 4 However, in a preferred embodiment of the invention, the step of making the aforementioned orifice is performed later, as will be more clearly presented in the following.

[0088] As in Figure 4 As shown in FIG. 1 , the profile elements include a first profile element referred to as an upper profile piece 12A, a second profile element referred to as a lower profile piece 12B, a third profile element referred to as a front profile piece 12C, and a fourth profile element referred to as a rear profile piece 12D.

[0089] The upper profile member 12A and the lower profile member 12B are arranged at the opposite ends, i.e., the upper end 10A and the lower end 10B, of the core 10. Similarly, the front profile member 12C and the rear profile member 12D are arranged at the opposite ends, i.e., the front end 10C and the rear end 10D, of the core 10, each of which connects the upper end 10A with the lower end 10B.

[0090] Each of the lower profile element 12B, the front profile element 12C and the rear profile element 12D integrally comprises a respective base 14 and its respective flanges 16B to 16D. Furthermore, the base 14 of each of these profile elements extends from one end of the corresponding flange 16B to 16D. Thus, each of these three profile elements has a configuration known as "angled". In the terminology of the present invention, the expression "angled" is intended to cover configurations in which the flanges 16B to 16D are orthogonal to the main front face 14A of the base 14 or are inclined at an angle greater than 45 degrees relative to the main front face 14A of the base 14.

[0091] By contrast, the base 14 of the upper profile 12A, in particular the main front face 14A of the base 14, extends on either side of the flange 16A of this upper profile at one end of said flange.

[0092] In addition, the base 14 of the upper profile member 12A includes an extension portion 14B inclined relative to the joint surface 24, and the extension portion 14B extends from the upper end portion of the corresponding main front face 14A while being inclined relative to the upper end portion of the corresponding main front face 14A, so that the extension portion 14B forms an obtuse angle Ω with the upper flange 16A and extends from opposite sides relative to the corresponding main front face 14A.

[0093] Step A) then comprises a step b) consisting in fastening the respective base 14 of the profile element 12 to the core 10 so that the respective flanges 16A to 16D of the profile element extend from a first side C1 relative to the core 10, as in Figure 5 , and such that the core 10 and the corresponding base 14 of the profile element 12 together form a main web 39 having a joining surface 24 which is preferably continuous and arranged on a second side C2 opposite to the first side C1, as described below ( Fig. 9 ) will be more clearly presented. Thus, the engagement surface 24 includes the main front face 14A of the base 14. As shown in Figure 5 As shown in , the extension 14B of the base of the upper profile 12A thus extends on the second side C2 .

[0094] In a preferred embodiment of the present invention, the base 14 is fastened to the core 10 in an edge-to-edge manner by friction stir welding (FSW). Figure 6 The weld bead 26 is allowed to be seen at the interface between the base 14 and the core 10 .

[0095] Furthermore, step A) comprises a step c) comprising providing first corner fittings 28, referred to as inner frame supports, each of which comprises a respective base 30 and shoulder 32 (one of these inner frame supports being provided at Figure 4 Furthermore, each of the inner frame supports 28 comprises a reinforcing web 33 in the form of an inclined plate.

[0096] After steps b) and c), step A) comprises a step d) consisting in fastening the respective base 30 of the inner frame support 28 to the main web 39, typically to at least one of the core 10 and the base 14 of the upper profile 12A, so that the respective shoulder 32 of the inner frame support 28 is arranged facing the flange 16A of the upper profile 12A and preferably in contact with the flange 16A of the upper profile 12A. In the example shown, the base 30 is fastened to the core 10. Figure 5 and Figure 6 The assembly thus constructed upon completion of step d) is shown.

[0097] In the case where the above-mentioned orifices are not preformed, step A) then comprises a step e) consisting in drilling these orifices 34 ( Figure 7 ), and preferably, step e) comprises forming countersunk holes around all or some of the openings in the profile element 12 ( Figure 7 and Figure 8 ).

[0098] The joining rib 37 obtained at the completion of step A) is Fig. 9 Visible in.

[0099] It should be noted that step A) for manufacturing the engagement ribs 37 may differ from the above description. The profile element 12 may be fastened to the core 10 by other means, for example by through-mounted fastening components. In other embodiments, the profile element 12 and the core 10 may be made in one part, for example by molding.

[0100] Independently of the method of manufacturing the joining rib 37, the joining rib 37 thus comprises a main web 39 from which the flanges 16A to 16D extend on a first side C1 and which defines a second side C2 of the joining surface 24. This main web 39 corresponds in the preferred embodiment of the invention described above to the assembly formed by the core 10 and by the base 14 of the profile element 12.

[0101] In any case, the main web 39 comprises, when step A) is completed, rows of orifices 34 opening on the second side C2 in the joining surface and on the first side C1 (opposite to said surface), these orifices 34 being therefore through holes.

[0102] The rows of apertures 34 comprise at least a first row of apertures R1 formed in the upper portion of the main web 39 and, where applicable, in the base 14 of the upper profile 12A, and a second row of apertures R2 formed in the lower portion of the main web 39 and, where applicable, in the base 14 of the lower profile 12B, as in Fig. 9 The rows R1 and R2 extend generally from the front side to the rear side of the joining ribs near the upper and lower ends of the main web 39, respectively.

[0103] Where applicable, some of the apertures in the first row of apertures R1 are aligned with apertures formed in corresponding bases 30 of inner frame supports 28, as described below ( Fig.10 ) will be presented more clearly in the following.

[0104] Furthermore, in a preferred embodiment of the invention, the rows of apertures 34 include a third row of apertures R3 which generally extend from the front side to the rear side of the engagement rib and are formed in the upper portion of the main web 39 and, where applicable, in the base 14 of the upper profile 12A ( Fig. 9), so that the first row R1 and the third row R3 of apertures are respectively arranged (and appear) on either side of the upper flange 16A. Thus, the first row R1 is located between the core 10 and the third row R3, or more generally between the second row R2 and the third row R3.

[0105] The rows of apertures 34 also include a fourth row of apertures R4 and a fifth row of apertures R5, the fourth row of apertures R4 being formed in the front portion of the main web 39 and, where applicable, in the base 14 of the front profile 12C, and a fifth row of apertures R5 being formed in the rear portion of the main web 39 and, where applicable, in the base 14 of the rear profile 12D. The rows R4 and R5 extend generally from the lower side to the upper side of the engagement ribs close to the front and rear ends of the main web 39, respectively.

[0106] The rows R1, R2, R4 and R5 are each arranged in a corresponding portion of the base 14 by means of which the corresponding profile element 12 is fastened to the core 10. In the case of the lower profile piece 12B, the front profile piece 12C and the rear profile piece 12D, the above-mentioned portion corresponds to the entire base 14. In the case of the upper profile piece 12A, the above-mentioned portion is the portion 38 of the base 14 located towards the core 10 relative to the upper flange 16A.

[0107] Where applicable, the extension 14B extends from an upper end of the upper part of the main web 39 on the second side C2 .

[0108] In a preferred embodiment of the present invention, the flanges 16A to 16D are formed by corresponding fillets 40 ( Figure 8 ) is connected to the base 14, and the countersunk hole 36 is formed through the fillet 40. Each of the fillets 40 has a discontinuous bend 42 at its connection with the corresponding base 14. Such a discontinuous bend makes it possible to increase the radius of curvature of the fillet 40 without increasing the extent of the base 14 in a direction orthogonal to the corresponding flanges 16A to 16D. The fillet 40 therefore has a relatively large thickness, which allows the fillet 40 to have a reinforcing effect within the profile element 12.

[0109] In a preferred embodiment of the invention, rows R1 , R2 , R4 and R5 are provided with countersunk holes 36 , whereas row R3 is free of countersunk holes 36 .

[0110] In any case, it should be noted that, at the completion of step A) of the method, the majority of the orifices 34, or preferably all of the orifices 34, are in a vacant state. This means that, in the case where some of the orifices 34 are aligned with the orifices formed in the corresponding base 30 of the inner frame support 28, said orifices 34 can be passed through by means of components for temporary fastening, thus ensuring the fastening of the base 30 to the main web 39. However, the other orifices 34 are in a vacant state, that is to say, they are not occupied and can therefore subsequently accommodate fastening components. In the case where none of the orifices 34 are used to fasten the base 30 to the main web 39, all of the orifices 34 are in a vacant state. In any case, it is clear that the orifices 34 in a vacant state do not contribute to the fastening of the profile element 12 to the core 10, or more generally to the mutual assembly of the elements constituting the engaging rib 37.

[0111] Reference Fig.10 , Fig.11 and Fig. 20 , step i) then comprises:

[0112] - a step B) consisting in providing a second corner fitting 44 , called upper outer fitting, comprising a respective base 46 and a shoulder 48 ;

[0113] - a step C) comprising providing a strip 50; and

[0114] - Step D) includes providing a central wing box 52, which includes at least an upper panel 54A, a lower panel 54B, a front member 54C connecting the front end of the upper panel to the front end of the lower panel, and a rear member 54D connecting the rear end of the upper panel to the rear end of the lower panel.

[0115] The upper panel 54A, the lower panel 54B, the front member 54C and the rear member 54D thus define an interior space 55 of the central wing box, which is located at the lateral ends 56 of the central wing box 52 (only one of the lateral ends 56 is located at Figures 9 to 18 (see Figure 1) is open.

[0116] The upper panel 54A and the lower panel 54B are provided with reinforcements 53 at their respective inner front faces in a known manner.

[0117] The shoulder 48 of the upper outer fitting 44 includes an aperture 58 ( Figure 10 to Figure 11 ), the orifices 58 are arranged so as to be able to align with all or some of the orifices in the third row R3 of orifices 34, respectively.

[0118] The strip 50 preferably includes a proximal portion 50A and a distal portion 50B, which are inclined relative to each other so that, in cross section, the upper front face of the distal portion 50B forms an angle θ relative to the upper front face of the proximal portion 50A, which extends generally parallel to the directions X and Y. Of course, the angle θ is exclusively between 90 and 180 degrees, and the angle θ is preferably greater than 135 degrees.

[0119] In a preferred embodiment of the invention, the upper outer fitting 44 and the strip 50 are elements which, like the profile element 12 , are each produced in one piece, preferably by extrusion.

[0120] Reference Figure 12 to Figure 14 as well as Fig. 20 , step i) then comprises:

[0121] - Step E) consisting in placing the engagement ribs 37 at the lateral ends 56 of the central wing box (at the Fig.11 54A), so that the upper flange 16A faces the upper panel 54A and substantially contacts the upper panel 54A, and so that the lower flange 16B faces the lower panel 54B and substantially contacts the lower panel 54B; then,

[0122] - a step F), which comprises in particular: using a first through-mounted fastening member 60 (at Fig.10 The upper flange 16A is fastened to the upper panel 54A together with the base 46 of the upper outer fitting 44, and a second through-mount fastening member 62 ( Fig.10 ) The lower flange 16B and the proximal portion 50A of the belt 50 are fastened together to the lower panel 54B so that the distal portion 50B of the belt 50 extends beyond the engagement surface 24 in a direction away from the center wing box 52, the direction away corresponding to the direction from the first side C1 to the second side C2.

[0123] The upper outer fitting 44 is positioned so that the aperture 58 of its shoulder 48 is aligned with the apertures of the third row of apertures R3 of the upper profile 12A (as in Fig.15 ).

[0124] Step F) also comprises fastening the respective flanges 16C, 16D of the front profile 12C and the rear profile 12D to the front member 54C and the rear member 54D, respectively.

[0125] Figure 12 to Figure 14The central wing module 64 is illustrated, which is obtained when step i) is completed and which is made of the central wing box 52 and the engaging ribs 37 assembled together in the manner described above. For the sake of clarity, the fastening members 60 and 62 are not visible in these figures.

[0126] Reference Fig.15 , Fig.16 and Fig. 20 Step I) then includes: step ii), which generally includes providing a fuselage structural member 66 (which is Fig.15 , Fig.16 and Fig.19 and step iii), which generally comprises fastening the upper external fitting 44 to the fuselage structure 66.

[0127] More precisely, the fuselage structure 66 generally comprises a circumferential frame 68 and a skin 70 fastened to the circumferential frame 68. The circumferential frame 68 comprises (in the form of a single part or by assembly) respective third corner fittings 72, called outer frame supports, each comprising a respective base 74 and a shoulder 76, as well as a respective reinforcing web 77.

[0128] In this case, step iii) comprises: using a third through-mount fastening member 78 ( Fig.16 ) The respective shoulders 76 of the outer frame support 72 are respectively fastened to the respective shoulders 32 of the inner frame support 28. These parts 78 pass through the shoulders 32 and 76, through the base 46 of the upper outer fitting 44, and through the upper panel 54A of the center wing box 52.

[0129] In addition, step iii) includes: using a fourth through-mounted fastening member 80 ( Fig.15 and Fig.16 ) The skin 70 is fastened to the extension 14B of the engagement rib 37.

[0130] Fig.15 and Fig.16 A portion of the fuselage portion 81 obtained upon completion of step I) is thus shown.

[0131] Reference Fig.17 and Fig. 20 , the method for manufacturing an aircraft then comprises: a step II) comprising providing at least one wing 82 comprising a lateral wing box 84, which defines an internal space 85; and a step III) comprising positioning the end 86 of the lateral wing box 84 to face the engagement surface 24 of the engagement rib 37, so that the distal portion 50B of the strip 50 is positioned outside the internal space 85 of the lateral wing box 84.

[0132] The lateral wing box 84 includes upper and lower panels 84A, 84B and front members (not visible) and rear members 84D, each connecting the upper panel 84A to the lower panel 84B in a known manner.

[0133] Furthermore, the lateral wing box 84 comprises a fourth corner fitting 88 comprising a corresponding base 90 and a shoulder 92 , a fifth corner fitting 94 comprising a corresponding base 96 and a shoulder 98 , and a sixth corner fitting 100 comprising a corresponding base 102 and a shoulder 104 .

[0134] The base 90 of the fourth corner fitting 88 is fastened to the upper panel 84A within the inner space 85 of the lateral wing box, while the base 102 of the sixth corner fitting 100 is fastened to the upper panel 84A outside the inner space 85 of the lateral wing box. In the illustrated example, the base 90 and the base 102 are fastened to the upper panel 84A in a combined manner, i.e., using a joint for fastening components.

[0135] Furthermore, the base 96 of the fifth corner fitting 94 is fastened to the lower panel 84B within the inner space 85 of the lateral wing box.

[0136] The respective shoulders 92 , 98 and 104 of the fittings 88 , 94 and 100 comprise respective orifices 106 , 107 , 108 arranged to be alignable with the orifices 34 of the rows R1 , R2 and R3 , respectively, as will appear more clearly below.

[0137] At the completion of step III), the end 86 of the lateral wing box is substantially in contact with the engagement surface 24 .

[0138] Reference Fig.18 and Fig. 20 The method for manufacturing an aircraft then comprises a step IV) comprising fastening the lateral wing box 84 to the engagement rib 37 using fastening members 110, 112, 114 operating under tension / compression respectively engaged in the apertures 34 formed in the main web 39, and also comprising fastening the lateral wing box 84 to the distal end portion 50B of the belt 50 using a fifth through-mounted fastening member 116. The fastening members 110, 112, 114 operating under tension / compression and the fifth through-mounted fastening member 116 are fastened to the distal end portion 50B of the belt 50. Fig.17 It is also visible in the unassembled state.

[0139] In a preferred embodiment of the present invention, the fastening member operating under tension / compression includes a sixth through-mount fastening member 110 that passes through an aperture 106 ( Fig.17 ) and is installed through the aperture 34 in the first row of apertures R1.

[0140] In addition, the fastening components operating under tension / compression include a seventh through-mount fastening component 112 that passes through an aperture 107 ( Fig.17 ) and is mounted through an aperture 34 in the second row of apertures R2.

[0141] Finally, the fastening components operating under tension / compression include an eighth through-mount fastening component 114 that passes through an aperture 108 ( Fig.17 ), through the aperture 34 in the third row of apertures R3, and through the aperture 58 of the shoulder 48 of the upper outer fitting 44.

[0142] The fastening members 110, 112, 114 operating under tension / compression are preferably bolts. The fastening members 60, 62, 78, 80, and 116 are preferably also bolts. It will be appreciated by those skilled in the art that because of the arrangement of the fastening members 60, 62, 80, and 116, the fastening members 60, 62, 80, and 116 primarily operate under shear.

[0143] Bringing the wing 82 into contact with the engagement surface 24 is made possible by the fact that, in any cross-sectional plane of the central wing module 81, the extension 14B of the engagement rib 37 has a lower front face (that is, arranged towards the lower front face of the wing 82) that forms an angle α with a horizontal plane XY parallel to the directions X and Y that is greater than the angle α formed by the upper front face of the distal portion 50B of the strip 50 relative to the plane XY ( Fig.15 In other words, the plane P1 of the lower front face of the extension portion 14B and the plane P2 of the upper front face of the distal end portion 50B have an intersection point located at the first side C1 with respect to the engagement surface 24 .

[0144] Fig.19 An example aircraft 120 obtained upon completion of the method according to the invention is illustrated very schematically.

[0145] Although the method in its general definition relates to only one side of the aircraft (that is to say, the wing 82, the engaging rib 37, and the corresponding lateral end 56 of the central wing box 52), the method is of course intended to be implemented in a similar manner with respect to the opposite side of the aircraft in order to fasten the second wing 82' to the fuselage portion 81 by means of a second engaging rib 37' arranged at the other lateral end of the central wing box.

[0146] The present invention has several advantages.

[0147] First, the engagement ribs 37 may be manufactured in parallel with the manufacturing operations of the center wing box 52 at an upstream stage of aircraft assembly.

[0148] The configuration of the engagement rib 37 effectively allows the engagement rib 37 to be assembled to the center wing box 52 after the center wing box 52 has been assembled.

[0149] Assembling the different profile elements 12 to the core 10 by FSW, where applicable, enables saving time and weight and proves to be easier to carry out than assembly by bolting or riveting.

[0150] Furthermore, the method enables the maximum number of elements to be incorporated into the central wing module, and therefore, at an upstream stage of aircraft assembly, wherein said elements include the upper external fitting 44 , the inner frame support 28 and the belt 50 .

[0151] Pre-drilling the orifices 34 also makes it possible to avoid having to carry out these operations during the final assembly phase of the aircraft.

[0152] The use of fastening elements 110 , 112 , 114 operating under tension / compression combined with the integral configuration of the engagement rib 37 makes it possible to minimize the number and complexity of the operations during the final assembly phase of the aircraft.

[0153] It should be noted that, as a variant, the upper outer fitting 44 may be replaced by a plurality of fittings configured to be juxtaposed along the base 14 of the upper profile 12A with or without spacing between them. The same applies to the corner fittings 88 , 94 , 100 of the lateral wing box 84 .

[0154] In any case, the third row of orifices R3 allows the main web 39 to directly absorb the tension / compression forces applied by the lateral wing box 84 to the engagement ribs 37 .

Claims

1. A joining rib (37) designed for a wing-to-center wing box joining of an aircraft, the joining rib (37) comprising a main web (39) and an upper flange (16A) and a lower flange (16B), the upper flange (16A) and the lower flange (16B) extending from the main web (39) on a first side (C1) relative to the main web (39), wherein: The main web (39) has a joining surface (24) arranged on a second side (C2) opposite to the first side, and the main web (39) includes a row of openings (34) open on the first side (C1) and on the second side (C2) in the joining surface, the row of openings at least including a first row of openings (R1) formed in the upper part of the main web (39) and extending from the front side of the joining rib toward the rear side, a second row of openings (R2) formed in the lower part of the main web (39) and extending from the front side of the joining rib toward the rear side, and a third row of openings (R3) formed in the upper part of the main web (39) and extending from the front side of the joining rib toward the rear side, so that the first row of openings (R1) and the third row of openings (R3) are respectively arranged on either side of the upper flange (16A), and each of the rows of openings (34) includes an opening in an empty state.

2. The joining rib according to claim 1 comprises an extension portion (14B) inclined relative to the joining surface (24), and the extension portion (14B) extends from the upper end portion of the upper part of the main web (39) on the second side (C2) to form an obtuse angle with the upper flange (16A) in cross section.

3. The joining rib according to any one of claims 1 and 2, further comprising a front flange (16C) and a rear flange (16D), the front flange (16C) and the rear flange (16D) extending from the main web (39) on the first side (C1) relative to the main web (39), and wherein, The rows of holes (34) also include a fourth row of holes (R4) formed in the front portion of the main web (39) and arranged from the lower side of the joining rib toward the upper side, and a fifth row of holes (R5) formed in the rear portion of the main web (39) and arranged from the lower side of the joining rib toward the upper side.

4. A method for manufacturing a joining rib (37) according to any one of claims 1 to 3, the method comprising at least the following steps: a) providing a core (10) and profile elements (12), each of which comprises a respective base (14) and a respective flange (16A to 16D) extending so as to protrude from the base; then b) fastening the respective base (14) of the profile element (12) to the core (10) such that the respective flange (16A to 16D) of the profile element (12) extends on a first side relative to the core corresponding to the first side (C1), the core (10) and the respective base (14) of the profile element together forming the main web (39); And among them, At the end of the method, the main web (39) comprises at least the row of openings (34), comprising at least the first row of openings (R1) formed in the base (14) of a first profile element, referred to as the upper profile piece (12A), of the profile element (12) and the second row of openings (R2) formed in the base (14) of a second profile element, referred to as the lower profile piece (12B), of the profile element (12), the upper profile piece and the lower profile piece being arranged at two opposite ends of the core, referred to as the upper end (10A) and the lower end (10B), so that the upper profile piece The base (14) of the upper profile member (12A) forms the upper part of the main web (39) and the flange of the upper profile member (12A) forms the upper flange (16A), and the base (14) of the lower profile member (12B) forms the lower part of the main web (39) and the flange of the lower profile member (12B) forms the lower flange (16B), wherein the base (14) of the upper profile member (12A) extends on either side of the flange (16A) of the upper profile member and includes the third row of openings (R3), and each row of openings (34) includes openings in an empty state.

5. The method according to claim 4, wherein: Each of the profile elements (12B, 12C, 12D) except the upper profile piece (12A) also has an angled configuration.

6. The method according to any one of claims 4 and 5, further comprising the steps of: c) providing first corner fittings, referred to as inner frame supports (28), each comprising a respective base (30) and shoulder (32); then d) After said step b), fastening said respective base (30) of said inner frame support (28) to said main web (39).

7. A method for producing a joining rib (37) according to claim 3 according to any one of claims 4 to 6, wherein: The rows of apertures (34) further comprise a fourth row of apertures (R4) formed in a third profile element, referred to as the front profile element (12C), and a fifth row of apertures (R5) formed in a fourth profile element, referred to as the rear profile element (12D), of the profile elements, the front profile element and the rear profile element being arranged at two opposite ends of the core (10), referred to as the front end portion (10C) and the rear end portion (10D), respectively. 0D) connects the upper end (10A) of the core to the lower end (10B) so that the base (14) of the front profile (12C) forms the front part of the main web (39) and the flange (16C) of the front profile forms the front flange (16C), and so that the base (14) of the rear profile (12D) forms the rear part of the main web (39) and the flange of the rear profile (12D) forms the rear flange (16D).

8. A method for manufacturing a center wing module (64) for an aircraft, the method comprising at least the following steps: A) producing at least one engaging rib (37) according to any one of claims 1 to 3 by means of a method according to any one of claims 4 to 7; B) providing at least one second corner fitting, referred to as an upper outer fitting (44), said upper outer fitting (44) comprising a base (46) and a shoulder (48); C) providing at least one strip (50); D) providing a central wing box (52), the central wing box (52) comprising at least an upper panel (54A), a lower panel (54B), a front member (54C) and a rear member (54D), the front member (54C) connecting the front end of the upper panel to the front end of the lower panel, and the rear member (54D) connecting the rear end of the upper panel to the rear end of the lower panel, so that the upper panel and the lower panel and the front member and the rear member define an internal space (55) of the central wing box (52), and the internal space (55) is open at at least one lateral end (56) of the central wing box; and then E) arranging the engagement rib (37) at the lateral end (56) of the center wing box by inserting the flanges (16A to 16D) into the inner space (55) of the center wing box so that the upper flange (16A) faces the upper panel (54A) and the lower flange (16B) faces the lower panel (54B); and then F) fastening the upper flange (16A) and the base (46) of the at least one upper external fitting (44) together to the upper panel (54A) using a first through-mount fastening member (60), and fastening the lower flange (16B) and the proximal portion (50A) of the at least one strip (50) together to the lower panel (54B) using a second through-mount fastening member (62), such that the distal portion (50B) of the at least one strip (50) extends beyond the engagement surface (24) in a direction away from the center wing box (52).

9. The method according to claim 8, wherein: The joining rib (37) complies with claim 3, or wherein the step A) includes manufacturing the joining rib (37) according to the method of claim 7, and wherein the step F) also includes fastening the front flange (16C) and the rear flange (16D) to the front member (54C) and the rear member (54D), respectively.

10. The method according to claim 8 or 9, wherein: The distal portion (50B) of the at least one ribbon-like member (50) forms an angle (θ) in cross-section relative to the proximal portion (50A) of the at least one ribbon-like member.

11. The method according to any one of claims 8 to 10, wherein: The engaging rib (37) is in accordance with claim 2, or wherein: Said step A) comprises manufacturing said engagement rib (37) according to the method of claim 6, and wherein said shoulder (48) of said at least one upper external fitting (44) comprises apertures (58) respectively aligned with the apertures (34) in said third row (R3) of apertures.

12. A method for manufacturing a fuselage section (81) for an aircraft, the method comprising at least the following steps: i) Manufacturing a central wing module (64) for an aircraft according to the method of any one of claims 8 to 11; ii) providing a fuselage structural member (66); iii) fastening said at least one upper external fitting (44) to said fuselage structure (66).

13. The method according to claim 12, wherein: - said step A) of said step i) comprises manufacturing said engaging rib (37) according to the method of claim 6; - the fuselage structure (66) comprises a circumferential frame provided with respective third corner fittings called outer frame supports (72), the outer frame supports (72) each comprising a respective base (74) and a shoulder (76); and - said step iii) comprises fastening respective shoulders (76) of said outer frame support (72) to respective shoulders (32) of said inner frame support (28) using third through-mount fastening members (78).

14. The method according to claim 12 or 13, wherein: - the engaging rib (37) is in accordance with claim 2; - the fuselage structure (66) comprises a skin (70); and - said step iii) comprises fastening said skin (70) to said extension (14B) using a fourth through-mount fastening member (80).

15. A method for manufacturing an aircraft (120), the method comprising at least the following steps: 1) Manufacturing a fuselage section (81) according to the method according to any one of claims 12 to 14; II) providing at least one wing (82), said at least one wing (82) comprising a lateral wing box (84) defining an interior space (85); then III) positioning the end (86) of the lateral wing box (84) facing the engagement surface (24) so ​​that the distal end portion (50B) of the at least one strip (50) is positioned outside the internal space (85) of the lateral wing box; and then IV) fastening the lateral wing box (84) to the engagement rib (37) using fastening members (110, 112, 114) operating under tension / compression and respectively engaging in the apertures (34) in the row of apertures, and fastening the lateral wing box (84) to the distal portion (50B) of the at least one strap (50) using a fifth through-mounted fastening member (116).

16. The method according to claim 15, wherein: - the lateral wing box (84) comprises an upper panel (84A) and a lower panel (84B) and at least one fourth corner fitting (88) and at least one fifth corner fitting (94); - said at least one fourth corner fitting and said at least one fifth corner fitting each comprise a respective base and a respective shoulder; - a base (90) of said at least one fourth corner fitting (88) is fastened to said upper panel (84A) of said lateral wing box within said internal space (85) of said lateral wing box; - the base (96) of the at least one fifth corner fitting (94) is fastened to the lower panel (84B) of the lateral wing box within the internal space (85) of the lateral wing box; - said fastening means operating under tension / compression comprises a sixth through-mounted fastening means (110) mounted through an aperture (106) formed in a shoulder (92) of said at least one fourth corner fitting (88) and an aperture (34) in said first row of apertures (R1); and - The fastening components operating under tension / compression include a seventh through-mounted fastening component (112) which is mounted through an aperture (107) formed in a shoulder (98) of the at least one fifth corner fitting (94) and an aperture (34) in the second row of apertures (R2).

17. The method according to claim 16, wherein: - said step i) of said step I) comprises manufacturing said central wing module (64) according to the method of claim 11; - the lateral wing box (84) comprises at least one sixth corner fitting (100), the at least one sixth corner fitting (100) comprising a base and a shoulder; - the base (102) of the at least one sixth corner fitting (100) is fastened to the upper panel (84A) outside the internal space of the lateral wing box; and - The fastening components operating under tension / compression include an eighth through-mounted fastening component (114), which is installed through an aperture (108) formed in the shoulder (104) of the at least one sixth corner fitting (100), an aperture (34) in the third row of apertures (R3), and an aperture (58) in the shoulder (48) of the at least one upper outer fitting (44).

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