Compression energy absorption device comprising star-shaped absorption tubes; aircraft comprising at least one such device

The star-shaped absorption tubes in the compression energy absorption device address the limitations of existing modules by increasing the cross-sectional area of cells, enhancing energy absorption and impact resistance in aircraft structures.

FR3159588B1Active Publication Date: 2026-04-17AIRBUS OPERATIONS (SAS)
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Patent Information

Authority / Receiving Office
FR · FR
Patent Type
Patents
Current Assignee / Owner
AIRBUS OPERATIONS (SAS)
Filing Date
2024-02-23
Publication Date
2026-04-17

AI Technical Summary

Technical Problem

Existing compression energy absorption modules in aircraft, such as those described in US patent 9,637,212, are ineffective in absorbing a large amount of energy due to their honeycomb structure with conduits oriented parallel to the deformation direction, limiting their capacity to absorb impact forces effectively.

Method used

A compression energy absorption device featuring star-shaped absorption tubes oriented along the compression direction, connected by junction walls to form cells with alternating protrusions and hollows, allowing for a higher cross-sectional area and improved energy absorption capability.

Benefits of technology

The star-shaped design significantly enhances the module's ability to absorb energy, enabling it to handle larger impact forces by increasing the cross-sectional area of the cells, thus providing better protection against vertical impacts.

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Abstract

The invention relates to a compression energy absorption device comprising star-shaped absorption tubes and to an aircraft comprising at least one such device. The invention relates to a compression energy absorption device comprising several spaced absorption tubes (36), each having a star-shaped cross-section and oriented along a compression direction, and connecting walls (38) parallel to the compression direction and linking the absorption tubes (36) so as to define, with them, at least one cell (40). This solution allows for the absorption of a greater quantity of energy. The invention also relates to an aircraft comprising at least one such energy absorption device. Figure 6
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Description

Title of the invention: Compression energy absorption device comprising star-shaped absorption tubes, aircraft comprising at least one such device

[0001] The present application relates to a compression energy absorption device comprising star-shaped absorption tubes and to an aircraft comprising at least one such device.

[0002] According to one embodiment, a panel comprises first and second skins as well as a honeycomb structure, interposed between the first and second skins, which includes a plurality of conduits oriented perpendicular to the first and second skins. This honeycomb structure has a honeycomb geometry and comprises a plurality of identical, juxtaposed conduits with hexagonal cross-sections. Generally, the conduits have a reduced cross-section, which gives the panel high compressive strength (forces perpendicular to the skins). Such panels are not used as compression energy absorption modules.

[0003] According to an embodiment described in US patent 9,637,212, an aircraft includes a compression energy absorption module positioned between the fuselage skin and a fairing. This module includes a honeycomb structure comprising a plurality of conduits oriented parallel to the fuselage skin and the fairing. This honeycomb structure has a honeycomb geometry and comprises a plurality of identical, juxtaposed conduits with hexagonal cross-sections oriented in a direction perpendicular to a direction of deformation. This embodiment does not allow for the absorption of a large amount of energy.

[0004] The present invention aims to remedy all or part of the drawbacks of the prior art.

[0005] For this purpose, the invention relates to a compression energy absorption device configured to be positioned between first and second elements and to be subjected to compression forces oriented along a compression direction, said device comprising at least one compression energy absorption module which includes several absorption tubes oriented along the compression direction, spaced apart from each other and each having a first cross-section as well as first and second ends.

[0006] According to the invention, the first cross-section of the absorption tubes has a star shape. In addition, the compression energy absorption module includes connecting walls, parallel to the direction of compression, linking the absorption tubes so as to delimit with them at least one cell.

[0007] Such a compression energy absorption module makes it possible to absorb a large amount of energy.

[0008] According to another feature, each alveolus has a second cross-section greater than the first cross-section of each absorption tube bordering the alveolus.

[0009] According to another feature, the star shape comprises an alternation of arc-shaped protrusions and arc-shaped hollows.

[0010] According to another feature, the protrusions of the same absorption tube are identical and have apexes positioned on a first circle. In addition, the hollows of the same absorption tube are identical and have low points positioned on a second circle concentric to the first circle, the protrusions and hollows being regularly distributed around the absorption tube.

[0011] According to another feature, each absorption tube comprises first and second half-tubes assembled and positioned on either side of a plane of symmetry. Each half-tube comprises a central part having protrusions and hollows and first and second wings positioned on either side of the central part, the first wings of the first and second half-tubes being positioned on either side of the plane of symmetry, pressed against each other and connected to each other, the second wings of the first and second half-tubes being positioned on either side of the plane of symmetry, pressed against each other and connected to each other.

[0012] According to another feature, the compression energy absorption module comprises several rows of absorption tubes, the rows being substantially parallel to each other and oriented along a first direction, each row comprising at least two absorption tubes spaced apart and connected by at least one first junction wall positioned in a plane parallel to the first direction.

[0013] According to another feature, for each row, the plane of symmetry of each absorption tube coincides with the plane of the first junction walls.

[0014] According to another feature, each row extends between first and second ends. In addition, the compression energy absorption module comprises a first end junction wall connecting the first ends of the different rows and a second end junction wall connecting the second ends of the different rows, the first and second end junction walls being substantially perpendicular to the first direction of the rows.

[0015] According to another feature, at least one absorption tube of at least one row is connected to the first or second end junction wall, each half-tube of the absorption tube connected to the first or second end junction wall having an extension pressed against the first or second end junction wall and connected to the latter.

[0016] According to another feature, the compression energy absorption module comprises at least one intermediate junction wall, substantially parallel to the first and second end junction walls, connecting two first junction walls of two rows.

[0017] According to another feature, the compression energy absorption module comprises first, second, and third rows, the second row being positioned between the first and third rows. In addition, the absorption tubes of the first, second, and third rows have first, second, and third heights, respectively, the second height being less than the first or third height.

[0018] According to another feature, the compression energy absorption module comprises at least one end plate, at least one junction wall being connected to said end plate.

[0019] According to another feature, the end plate is spaced from the first or second end of all the absorption tubes of the compression energy absorption module.

[0020] According to another feature, the compression energy absorption module comprises a first end plate connected to the first edges of the junction walls and a second end plate connected to the second edges of the junction walls.

[0021] According to another feature, each end plate includes at least one orifice for each absorption tube as well as at least one opening for each alveolus.

[0022] The invention also relates to an aircraft comprising at least one compression energy absorption device according to one of the preceding characteristics.

[0023] Other features and advantages will become apparent from the following description of the invention, given by way of example only, with reference to the accompanying drawings, among which:

[0024] [Fig. 1] is a side view of an aircraft,

[0025] [Fig.2] is a perspective view of a lower part of an aircraft illustrating a method of embodiment of the invention,

[0026] [Fig.3] is a longitudinal section of a lower part of an aircraft fuselage comprising compression energy absorption modules in the undeformed state illustrating one embodiment of the invention,

[0027] [Fig.4] is a longitudinal section of a lower part of an aircraft fuselage comprising compression energy absorption modules in the deformed state illustrating one embodiment of the invention,

[0028] [Fig.5] is a perspective view of energy absorption modules by compression illustrating an embodiment of the invention, in the undeformed state on part (A) and in the deformed state on part (B),

[0029] [Fig.6] is a perspective view of an energy absorption module by compression illustrating one embodiment of the invention,

[0030] [Fig.7] is a section along plane P of the energy absorption modulus by compression visible on [Fig.6],

[0031] [Fig.8] is a perspective view of an absorption tube illustrating a mode of realization of the invention,

[0032] [Fig.9] is a perspective view of part of an energy absorption module by compression after a first assembly step illustrating one embodiment of the invention,

[0033] [Fig. 10] is a perspective view of part of a compression energy absorption module after a second assembly step illustrating one embodiment of the invention,

[0034] [Fig. 11] is a perspective view of part of a compression energy absorption module after a third assembly step illustrating one embodiment of the invention,

[0035] [Fig. 12] is a perspective view of a first junction wall illustrating one embodiment of the invention,

[0036] [Fig. 13] is a top view of a junction zone connecting an absorption tube and an end junction wall illustrating one embodiment of the invention, and

[0037] [Fig. 14] is a perspective view of end plates illustrating one embodiment of the invention.

[0038] According to an embodiment visible in [Fig.1], an aircraft 10 comprises a fuselage 12 extending from a front tip 12.1 to a rear tip 12.2, wings 14 positioned on either side of the fuselage 12 and an empennage 16 positioned at the rear tip 12.2 of the fuselage 12.

[0039] For the remainder of the description, a longitudinal direction is a direction parallel to a substantially horizontal longitudinal axis when the aircraft is on the ground, extending from the forward tip 12.1 to the rear tip 12.2. The aircraft 10 has a vertical longitudinal plane of symmetry containing the longitudinal axis.

[0040] The fuselage 12 also includes a primary structure 18 composed of frames and stringers and a skin 20 attached to the primary structure 18. It also includes a central wing box 22 and a landing gear bay 24 offset rearward relative to the central wing box 22. In one configuration, the fuselage 12 includes at least one fuel tank 26 offset rearward relative to the landing gear bay 24.

[0041] The aircraft 10 comprises a ventral fairing 28 extending below the center wing box 22, the landing gear bay 24, and the fuel tank 26, and has a width substantially equal to that of the fuselage 12. At least at the level of the fuel tank 26, the ventral fairing 28 and the fuselage 12 (more specifically, the skin 20 of the fuselage 12) are spaced apart. In one configuration, the fuel tank 26 is a structural tank partially integrated into the structure of the fuselage 12.

[0042] The aircraft 10 comprises at least one compression energy absorption device, interposed between the ventral fairing 28 and the fuselage 12 (more particularly the skin 20 of the fuselage 12), which includes at least one compression energy absorption module 30 interposed between the ventral fairing 28 and the fuselage 12 (more particularly the skin 20 of the fuselage 12). In one configuration, the aircraft 10 comprises at least one compression energy absorption module 30 interposed between the ventral fairing 28 and the tank 26, positioned below the latter. This configuration allows the addition of an additional tank 26 at the rear of the landing gear bay 24, said tank 26 being protected by at least one compression energy absorption module 30 in the event of a vertical impact at the ventral fairing 28. Consequently, the latter is not necessarily designed to absorb such an impact and protect the tank 26.

[0043] Of course, the invention is not limited to this arrangement. Thus, the compression energy absorption device could be positioned in another location on the aircraft. More generally, the compression energy absorption device is configured to be positioned between first and second elements 32, 34, more precisely between first and second contact surfaces F32, F34, and to be subjected to compression forces oriented along a compression direction DC (visible in [Fig. 4]) intersecting with the first and second elements 32, 34. According to a first arrangement, the first and second contact surfaces F32, F34 are substantially parallel to each other and substantially perpendicular to the compression direction DC. According to another arrangement, the first and second contact surfaces F32, F34 are not parallel to each other, and one of them is perpendicular to the compression direction DC.

[0044] Each compression energy absorption module 30 comprises several absorption tubes 36 spaced apart, oriented along the compression direction DC and each presenting a first cross-section (perpendicular to the compression direction DC) as well as junction walls 38, 38', 38" parallel to the compression direction DC and connecting the absorption tubes 36 so as to delimit, with the latter, at least one alveolus 40 which presents a second cross-section (perpendicular to the compression direction DC).

[0045] According to one configuration, the DC compression direction forms a small angle of the order of 6° with a vertical direction.

[0046] According to an embodiment visible in [Fig.8], each absorption tube 36 has a side wall 42 and extends between first and second ends 42.1, 42.2 oriented respectively in the direction of the first and second elements 32, 34.

[0047] According to an embodiment shown in [Fig. 7], the absorption tubes 36 of the same compression energy absorption module 30 all have the same cross-section. Each absorption tube 36 has a constant cross-section between its first and second ends 42.1, 42.2.

[0048] Alternatively, the absorption tubes 36 of the same compression energy absorption module 30 could have different cross-sections and / or which vary from one end to the other.

[0049] According to an embodiment visible in [Fig.8], the first cross-section of the absorption tubes 36 has a star shape 44 with an alternation of protrusions 44.1 to 44.6 and hollows 46.1 to 46.6.

[0050] According to one configuration, the star-shaped form 44 comprises six protrusions 44.1 to 44.6. Each protrusion 44.1, 44.6 describes, in top view, an arc of a circle. In addition, each recess 46.1 to 46.6 describes, in top view, an arc of a circle. Thus, the protrusions 44.1 to 44.6 and the recesses form a wavy profile.

[0051] According to one configuration, the protrusions 44.1 to 44.6 of an absorption tube 36 are all identical. Similarly, the recesses are identical. The protrusions 44.1 to 44.6 and the recesses 46.1 to 46.6 are regularly distributed around the absorption tube 36. The protrusions 44.1 to 44.6 have vertices positioned on a first circle CL. In addition, the recesses 46.1 to 46.6 have low points positioned on a second circle C2 concentric with the first circle CL.

[0052] According to one embodiment, each absorption tube 36 has a height, corresponding to the distance between the first and second ends 42.1, 42.2, of between 160 and 300 mm. Each protrusion 44.1, 44.6 has a radius of curvature of between 10 and 15 mm. To give an order of magnitude, each absorption tube 36 has a first cross-section of between 100 and 400 cm².

[0053] Each absorption tube 36 has at least one plane of symmetry PS passing through two opposite protrusions.

[0054] According to a configuration visible in figures 9, 10 and 13, each absorption tube 36 is obtained by assembling first and second half-tubes 48, 50 positioned on either side of the plane of symmetry PS. According to an arrangement visible in [Fig. 13], each half-tube 48, 50 comprises a corrugated central part 48.1, 50.1 having protrusions 44.1 to 44.6 and hollows 46.1 to 46.6, as well as first and second wings 48.2, 48.3, 50.2, 50.3 positioned on either side of the central part 48.1, 50.1. The first wings 48.2, 50.2 of the first and second half-tubes 48, 50 are positioned on either side of the plane of symmetry PS, pressed against each other and connected to each other. The second wings 48.3, 50.3 of the first and second half-tubes 48, 50 are positioned on either side of the plane of symmetry PS, pressed against each other. and connected to each other. According to an assembly method, the first and second wings 48.2, 50.2, 48.3, 50.Three are joined together by welding, riveting or any other means.

[0055] According to one embodiment, each of the first and second half-tubes 48, 50 is obtained by bending, stamping or any other suitable technique to obtain the protrusions 44.1 to 44.6 and the hollows 46.1 to 46.6.

[0056] According to embodiments visible in particular in Figures 9 and 12, each connecting wall 38, 38', 38" extends between first and second edges 38.1, 38.2, 38.1', 38.2', 38.1", 38.2" and third and fourth edges 38.3, 38.4, which are connected, for some connecting walls 38, to absorption tubes 36 or to another connecting wall 38. Thus, two connecting tubes 38 are connected by at least one connecting plate 38, 38', 38".

[0057] Generally, the joining walls 38 are planar. Alternatively, the joining walls 38 could be non-planar. In one embodiment, at least one joining wall 38 comprises a planar central portion 52.1, and at least one wing 52.2 located at the first or second edge 38.1, 38.2 forming a 90° angle with the central portion. In one configuration, the joining wall 38 comprises first and second wings 52.2, 52.3 located respectively at the first and second edges 38.1, 38.2, forming a 90° angle with the central portion 52.1 and folded in opposite directions.

[0058] According to an arrangement visible in [Fig. 7], each compression energy absorption module 30 comprises several rows 54, 54', 54" of absorption tubes 36, the rows 54, 54', 54" being substantially parallel to each other and oriented along a first direction, each row 54, 54', 54" comprising at least two absorption tubes 36 spaced apart and connected by at least one junction wall 38 parallel to the first direction. In one embodiment, each module The compression energy absorption unit 30 comprises three rows 54, 54', 54", and each row 54, 54', 54" comprises four absorption tubes 36 connected in pairs by three first connecting walls 38 of the same length, positioned in the same plane parallel to the first direction. For each row 54, 54', 54", the plane of symmetry PS of each absorption tube 36 coincides with the plane of the first connecting walls 38.

[0059] According to one assembly method, the absorption tubes 36 and the first connecting walls 38 are connected by welding, riveting or any other assembly technique.

[0060] When the compression energy absorption module 30 is integrated into an aircraft 10, the first direction is parallel to the longitudinal direction. The plane of the first junction walls 38 of the same row 54, 54', 54" contains the compression direction DC.

[0061] Each row 54, 54', 54" extends between the first and second ends. In addition to the first junction walls 38, the compression energy absorption module 30 comprises a first end junction wall 38' connecting the first ends of the different rows 54, 54', 54" and a second end junction wall 38' connecting the second ends of the different rows 54, 54', 54", the first and second end junction walls 38' being substantially perpendicular to the first direction of the rows 54, 54', 54". According to one configuration, at least one absorption tube 36 of at least one row 54, 54', 54" is connected to the first or second end junction wall 38'. Each row 54, 54', 54" includes at each of its ends an absorption tube 36 connected to the first or second end junction wall 38'. According to an embodiment shown in detail in the [Fig.

[13] , each half-tube 48, 50 of each absorption tube 36 connected to the first or second end junction wall 38' comprises, in the extension of its first or second wing 48.2, 50.2 oriented towards the first or second end junction wall 38', an extension 48.4, 50.4 forming an angle of approximately 90° with the corresponding first or second wing 48.2, 50.2, pressed against the first or second end junction wall 38' and connected to the latter by welding, riveting or any other assembly technique.

[0062] The compression energy absorption module 30 comprises at least one intermediate junction wall 38”, substantially parallel to the end junction walls 38', connecting the first two junction walls 38 of two rows 54, 54', 54'”. In one configuration, the compression energy absorption module 30 comprises two intermediate junction walls 38”, connecting the three rows 54, 54', 54'' in pairs, positioned equidistant from the first and second end junction walls 38'. In one embodiment shown in [Fig. 11], each intermediate junction wall 38” includes, at each of its ends, a flange 56 folded at 90°, pressed against a corresponding first junction wall 38 and connected to the latter by welding, riveting or any other assembly technique.

[0063] According to one embodiment, for each row 54, 54', 54”, the first ends 42.1 of the absorption tubes 36 and the first edges 38.1 of the connecting walls 38 are coplanar. In addition, the second ends 42.2 of the absorption tubes 36 and the second edges 38.2 of the connecting walls 38 are coplanar.

[0064] According to an arrangement, for the same compression energy absorption module 30, the first ends 42.1 of the absorption tubes 36 and the first edges 38.1 of the first junction walls 38' of the different rows 54, 54', 54” are coplanar.

[0065] According to one arrangement, the compression energy absorption module 30 comprises first, second, and third rows 54, 54', 54", with the second row 54' positioned between the first and third rows 54, 54". The absorption tubes 36 of the first row 54 have the same first height. The absorption tubes 36 of the second row 54' have the same second height. The absorption tubes 36 of the third row 54" have the same third height. The first and third heights are generally different. They could be equal. The second height is less than the first or third height.

[0066] The first and second end junction walls 38' comprise a first edge 38.1' coplanar with the first ends 42.1 of the absorption tubes 36 and the first edges 38.1 of the first junction walls 38 of the different rows 54, 54', 54" and a second edge 38.2' which comprises a first segment 38.2a' connecting the second ends 42.2 of the absorption tubes 36 of the first and second rows 54, 54' and a second segment 38.2b' connecting the second ends 42.2 of the absorption tubes 36 of the second and third rows 54', 54".

[0067] Each intermediate junction wall 38” includes a first edge 38.1” coplanar with the first ends 42.1 of the absorption tubes 36 and the first edges 38.1 of the first junction walls 38 of the different rows 54, 54', 54” and a second edge 38.2' connecting the second edges 38.2 of the second junction walls of the second row 54' and of the first or third row 54, 54' '.

[0068] According to the embodiment shown in Figures 6 and 7, the cells 40 each have a second approximately rectangular cross-section. Of course, the invention is not limited to this cross-section for the cells 40. Thus, the absorption tubes 36 and the connecting walls 38 could be connected so as to delimit cells 40 with other cross-sections such as prismatic, square, rectangular, triangular, or circular, for example, so as to form for example an orthogrid, isogrid or other type network. Furthermore, a compression energy absorption module 30 could comprise only a single cell 40.

[0069] According to one configuration, for each compression energy absorption module 30, the second cross-section of each cell 40 is greater than the first cross-section of the absorption tubes 36. According to one configuration, the second cross-section of each cell 40 is at least twice greater than the first cross-section of each absorption tube 36 bordering the cell 40. Such a compression energy absorption module makes it possible to absorb a greater amount of energy.

[0070] To give an order of magnitude, each cell 40 has a second cross-section of between 60000 and 70000 mm2.

[0071] According to one embodiment, the compression energy absorption module 30 comprises at least a first end plate 58 in contact with the first end 42.1 of at least one absorption tube 36 and connected to the latter. According to an embodiment visible in [Fig. 7], the first end plate 58 is spaced from the first end 42.1 of all the absorption tubes 36. The first edge 38.1, 38.1', 38.1" of at least one junction wall 38, 38', 38" is connected to the first end plate 58 of the compression energy absorption module 30. Preferably, the first edge 38.1, 38.1', 38.1" of all the junction walls 38, 38', 38" is connected to the first end plate 58 of the compression energy absorption module 30. According to one embodiment, the wing 52.2 of each junction wall 38 connected to the first end plate 58 is pressed against the latter and connected to it.

[0072] This first end plate 58 includes at least one orifice 60 for each absorption tube 36 and at least one opening 62 for each alveolus 40. Each orifice 60 is circular and has a diameter that is less than, or slightly less than, that of the circle C2 of the star shape 44 of the absorption tubes 36. Each opening 62 is rectangular.

[0073] According to a configuration visible in [Fig. 14], the first end plate 58 has a rectangular perimeter with rounded corners and comprises, for each row 54, 54', 54”, a rectangular area 64, 64', 64” which has a width greater than or slightly greater than the diameter of the circle Cl of the star-shaped 44 of the absorption tubes 36, as well as, for each end or intermediate junction wall 38', 38”, a thin area 66 connecting the rectangular areas 64, 64', 64” to each other. The first end plate 58 is flat.

[0074] According to one embodiment, the compression energy absorption module 30 comprises at least a second end plate 68 in contact with the second end 42.2 of at least one absorption tube 36 and connected to the latter. According to an embodiment visible in [Fig. 6], the second end plate 68 is spaced from the second end 42.2 of all the absorption tubes 36. The second edge 38.2, 38.2', 38.2" of at least one junction wall 38, 38', 38" is connected to the second end plate 68 of the compression energy absorption module 30. Preferably, the second edge 38.2, 38.2', 38.2" of all the junction walls 38, 38', 38" is connected to the second end plate 68 of the compression energy absorption module 30. According to one embodiment, the wing 52.3 of each junction wall 38 connected to the second end plate 68 is pressed against the latter and connected to it.

[0075] This second end plate 68 includes at least one orifice 70 for each absorption tube 36 and at least one opening 72 for each alveolus 40. Each orifice 70 is circular and has a diameter that is less than, or slightly less than, that of the circle C2 of the star shape 44 of the absorption tubes 36. Each opening 72 is rectangular.

[0076] According to a configuration visible in [Fig. 14], the second end plate 68 has a rectangular perimeter with rounded corners and comprises, for each row 54, 54', 54”, a rectangular area 74, 74', 74” which has a width greater than or slightly greater than the diameter of the circle Cl of the star-shaped 44 of the absorption tubes 36, as well as, for each end or intermediate junction wall 38', 38”, a thin area 76 connecting the rectangular areas 74, 74', 74” to each other. The second end plate 68 comprises two faces inclined relative to each other to follow the profile of the end and intermediate junction walls 38', 38”.

[0077] Of course, the invention is not limited to these embodiments for the first and second end plates 68, 68. These end plates 58, 68 make it possible to increase the contact area between the compression energy absorption module 30 and the first and second elements 32, 34.

[0078] According to one embodiment, the junction walls 38, 38, 38” and the absorption tubes 36 of a compression energy absorption module 30 are made of aluminum alloy, in particular from aluminum alloy sheets.

[0079] The dimensions and the material(s) of the absorption tubes 36 and the junction walls 38, 38', 38" are determined so as to obtain a progressive crushing of the absorption tubes 36, promoting the absorption of energy and not a spillage of the latter.

[0080] According to an embodiment shown in Figures 9 to 11, an assembly method comprises a first assembly step, for each row 54, 54', 54”, of the first half-tubes 48 and the first joining walls 38, as illustrated on [Fig.9], a second step of assembling the second half-tubes 50 so as to form the absorption tubes 36, as illustrated on [Fig. 10], a third step of assembling the rows 54, 54', 54” and the end and intermediate junction walls 38', 38”, as illustrated on [Fig.11], and finally a step of assembling the first and second end plates 58, 68 so as to form the compression energy absorption module 30.

[0081] Of course, the invention is not limited to this embodiment for the assembly process.

[0082] According to one configuration, a compression energy absorption device comprises several compression energy absorption modules 30 positioned symmetrically with respect to the vertical longitudinal plane of symmetry of the aircraft.

[0083] According to one embodiment, the compression energy absorption device comprises at least one attachment system 78 connecting each compression energy absorption module 30 to at least one of the first and second elements 32, 34 between which said compression energy absorption module 30 is positioned. In one configuration, this attachment system 78 is configured to allow for quick mounting or dismounting of the compression energy absorption module 30.

[0084] In the case of an aircraft, each compression energy absorption module 30 includes several attachment systems 78 for connecting it to the fuselage 12 (more particularly to the skin 20 of the fuselage 12) and / or to the ventral fairing 28. According to one configuration, each compression energy absorption module 30 is connected to only one element among the first and second elements 32, 34. According to one arrangement, with the second element 34 offset upwards relative to the first element 32 (when the aircraft is on the ground), each compression energy absorption module is suspended below the second element 34, namely the fuselage 12 or the tank 26.

Claims

Demands

1. Compression energy absorption device configured to be positioned between first and second elements (32, 34) and to be subjected to compression forces oriented along a compression direction (DC), said compression energy absorption device comprising at least one compression energy absorption module (30) which includes several absorption tubes (36) oriented along the compression direction (DC), spaced apart from each other and each having a first cross-section as well as first and second ends (42.1, 42.2); characterized in that the first cross-section of the absorption tubes (36) has a star shape (44) and in that the compression energy absorption module (30) includes junction walls (38, 38', 38"), parallel to the compression direction (DC), connecting the absorption tubes (36) so as to delimit with the latter at least one cell (40).

2. Compression energy absorption device according to the preceding claim, characterized in that each cell (40) has a second cross-section greater than the first cross-section of each absorption tube (36) bordering the cell (40).

3. Compression energy absorption device according to any one of the preceding claims, characterized in that the star shape (44) comprises an alternation of circular arc protrusions (44.1 to 44.6) and circular arc hollows (46.1 to 46.6).

4. Compression energy absorption device according to the preceding claim, characterized in that the protrusions (44.1 to 44.6) of the same absorption tube (36) are identical and have apexes positioned on a first circle (Cl) and in that the hollows (46.1 to 46.6) of the same absorption tube (36) are identical and have low points positioned on a second circle (C2) concentric to the first circle (Cl), the protrusions (44.1 to 44.6) and the hollows (46.1 to 46.6) being regularly distributed around the absorption tube (36).

5. Compression energy absorption device according to the preceding claim, characterized in that each absorption tube (36) comprises first and second half-tubes (48, 50) assembled and positioned on either side of a plane of symmetry (PS), and in that each half-tube (48, 50) comprises a central part (48.1, 50.1) having the projections (44.1 to 44.6) and the hollows (46.1 to 46.6) as well as first and second wings (48.2, 48.3, 50.2, 50.3) positioned on either side of the central part (48.1, 50.1), the first wings (48.2, 50.2) of the first and second half-tubes (48, 50) being positioned on either side of the plane of symmetry (PS), pressed against each other and connected to each other, the second wings (48.3, 50.3) of the first and second half-tubes (48, 50) being positioned on either side of the plane of symmetry (PS), pressed against each other and connected to each other.

6. Compression energy absorption device according to any one of the preceding claims, characterized in that the compression energy absorption module (30) comprises several rows (54, 54', 54") of absorption tubes (36), the rows (54, 54', 54") being substantially parallel to each other and oriented along a first direction, each row (54, 54', 54") comprising at least two absorption tubes (36) spaced apart and connected by at least one first junction wall (38) positioned in a plane parallel to the first direction.

7. Compression energy absorption device according to claims 5 and 6, characterized in that, for each row (54, 54', 54"), the plane of symmetry (PS) of each absorption tube (36) coincides with the plane of the first junction walls (38).

8. Compression energy absorption device according to any one of claims 6 to 7, characterized in that each row (54, 54', 54") extends between first and second ends and in that the compression energy absorption module (30) comprises a first end junction wall (38') connecting the first ends of the different rows (54, 54', 54") and a second end junction wall (38') connecting the second ends of the different rows (54, 54', 54"), the first and second end junction walls (38') being substantially perpendicular to the first direction of the rows (54, 54', 54").

9. Compression energy absorption device according to the preceding claim, characterized in that at least one absorption tube (36) of at least one row (54, 54', 54") is connected to the first or second end junction wall (38'), each half-tube (48, 50) of the absorption tube (36) connected to the first or second end junction wall (38') having an extension (48.4, 50.4) pressed against the first or second end junction wall (38') and connected to the latter.

10. Compression energy absorption device according to any one of claims 8 to 9, characterized in that the compression energy absorption module (30) comprises at least one intermediate junction wall (38”), substantially parallel to the first and second end junction walls (38'), connecting two first junction walls (38) of two rows (54, 54', 54”).

11. Compression energy absorption device according to any one of claims 6 to 10, characterized in that the compression energy absorption module (30) comprises first, second and third rows (54, 54', 54"), the second row (54') being positioned between the first and third rows (54, 54") and in that the absorption tubes (36) of the first, second and third rows (54, 54', 54") have first, second and third heights respectively, the second height being less than the first or third height.

12. Compression energy absorption device according to any one of the preceding claims, characterized in that the compression energy absorption module (30) comprises at least one end plate (58, 68), at least one junction wall (38, 38', 38") being connected to said end plate (58, 68).

13. Compression energy absorption device according to the preceding claim, characterized in that the end plate (58, 68) is spaced from the first or second end (42.1) of all the absorption tubes (36) of the compression energy absorption module (30).

14. Compression energy absorption device according to the preceding claim, characterized in that the compression energy absorption module (30) comprises a first end plate (58) connected to the first edges (38.1, 38.1', 38.1”) of the junction walls (38, 38', 38”) and a second end plate (68) connected to the second edges (38.2, 38.2', 38.2”) of the junction walls (38, 38', 38”).

15. Compression energy absorption device according to any one of claims 12 to 14, characterized in that each plate

16. end (58, 68) includes at least one orifice (60) for each absorption tube (36) as well as at least one opening (62) for each alveolus (40). Aircraft comprising at least one compression energy absorption device according to one of the preceding claims.