Overpressure device and aircraft equipped with at least one such device

Abstract

Overpressure device and aircraft equipped with at least one such device. The invention relates to an overpressure device comprising at least one wall (38) movable between closed and open positions and isolating, in the closed position, inner and outer zones (ZI, ZE). The overpressure device includes at least one system for holding the wall (38) in the closed position, comprising at least one fusible element (56) housed astride a first housing (58) integral with a first movable part (42) of the wall (38) and a second housing (60) integral with a second movable part of the wall (38) or a fixed element, the fusible element (56) being configured so as to remain intact when the pressure in the inner zone (ZI) is less than a given value and to rupture when this pressure is greater than or equal to the given value.This design reduces the mass, size, and cost of each restraint system (54). The invention also relates to an aircraft comprising at least one such overpressure device. Figure 14.

Description

Title of the invention: Overpressure device and aircraft equipped with at least one such device

[0001] The present application relates to an overpressure device comprising at least one fusible element to maintain it in a closed position and to an aircraft equipped with at least one such device.

[0002] According to an embodiment shown in Figures 1 and 2, an aircraft 10 comprises a fuselage 12, wings 14 positioned on either side of the fuselage 12 and connected to it, propulsion units 16 positioned under the wings 14, and pylons 18 connecting the propulsion units 16 to the wings 14. Each pylon 18 comprises a primary structure ensuring the transmission of forces between the propulsion unit 16 and the wing 14 it connects, and a secondary structure 20 (shown in [Fig. 2]) which encloses the primary structure and forms an aerodynamic surface. This secondary structure 20 comprises a hot air exhaust 22, provided with a static grille, and a pressure relief door 24.

[0003] When the pressure in an internal zone located below the secondary structure 20 is less than a given value, the pressure relief gate 24 is in a closed position. As soon as the pressure in the internal zone accidentally exceeds this given value, the pressure relief gate 24 opens to the open position.

[0004] According to an embodiment visible in figures 3 to 5, the overpressure gate 24 has front and rear edges 24.1, 24.2 substantially perpendicular to a vertical median plane PMV and lateral edges 24.3, 24.4 substantially symmetrical with respect to the vertical median plane PMV.

[0005] The pressure relief gate 24 is connected to the rest of the secondary structure 20 by a joint 26, such as a hinge or goosenecks for example, positioned at the front edge 24.1 and allowing the pressure relief gate 24 to pivot between the closed and open positions.

[0006] To maintain it in the closed position, the pressure relief door 24 includes two locking systems 28 positioned symmetrically with respect to the vertical median plane PMV. Each locking system 28 includes a movable latch between a locked state in which it maintains the pressure relief door 24 in the closed position and an unlocked state in which it allows the pressure relief door 24 to swing into the open position, as well as a spring for maintaining the latch in the locked state against forces, in particular those generated by the pressure difference between the inner and outer zones.

[0007] Each locking system 28 includes an adjustment system allowing the pressure at which the lock switches from the locked state to the unlocked state to be adjusted, and permitting the overpressure door 24 to pivot into the open position.

[0008] In addition, the overpressure door 24 includes a holding mechanism 30 in a half-open position such as a link for example.

[0009] In practice, the tilting of the overpressure gate 24 into the open position occurs only very rarely.

[0010] This embodiment is not entirely satisfactory because the joint 26, the locking systems 28 and the retaining mechanism 30 are relatively bulky, expensive and have a significant mass in view of the frequency of the tilting of the pressure relief door 24 into the open position.

[0011] The present invention aims to remedy all or part of the drawbacks of the prior art.

[0012] To this end, the invention relates to an overpressure device comprising at least one wall configured to occupy a closed position in which the wall closes an opening and isolates interior and exterior zones positioned on either side of the wall, as well as an open position in which the wall at least partially clears the opening, the wall comprising at least one movable part relative to a fixed element, the overpressure device comprising at least one articulation configured to connect the movable part and the fixed element, as well as at least one holding system configured to maintain the wall in the closed position as long as a pressure in the interior zone is less than a given value, each movable part being animated by an opening movement around a pivot axis when the wall passes from the closed position to the open position.

[0013] According to the invention, the holding system comprises at least one fusible element housed astride a first housing integral with a first movable part and in a second housing integral with a second movable part or a fixed element, the fusible element being configured so as to remain intact when the pressure in the inner zone is less than the given value and to break when the pressure in the inner zone is greater than or equal to the given value.

[0014] This solution makes it possible to reduce the size, mass and costs of each support system.

[0015] According to another feature, the fusible element is a pin having an axis oriented substantially perpendicular to the opening movement.

[0016] According to another characteristic, the first and second housings open at the level of first and second faces parallel to each other, in contact with each other or very slightly spaced apart, substantially parallel to the opening movement.

[0017] According to another feature, the wall comprises at least one fixed part and each joint has at least one fold line connecting at least one fixed part and at least one movable part of the wall, the passage into the open position being obtained by plastic deformation of the wall approximately along the fold line.

[0018] According to another feature, at least one fixed part of the wall is connected by connecting elements to a fixed element, the connecting elements being aligned and positioned approximately along the fold line separating the fixed part and the moving part connected to the fixed part.

[0019] According to another feature, the wall comprises at least first and second lateral parts separated by a median cutout. In addition, the overpressure device comprises at least a first retaining system having at least a first fusible element positioned on either side of the median cutout.

[0020] According to another feature, the wall comprises a central portion, a first cutout separating the central portion and the first lateral portion, and a second cutout separating the central portion and the second lateral portion. In addition, the overpressure device comprises at least one second retaining system having at least one second fusible element positioned on either side of the first cutout, and at least one third retaining system having at least one third fusible element positioned on either side of the second cutout.

[0021] According to another feature, the wall comprises first and second edges substantially perpendicular to a vertical median plane, as well as lateral edges connecting the first and second edges, symmetrical with respect to the vertical median plane. In addition, each of the first and second cutouts comprises: a. a first section, substantially perpendicular to the vertical median plane and spaced from the second edge of the wall, extending from the median cut towards the third or fourth edge of the wall, b. a second section, substantially parallel to the vertical median plane and spaced from the third or fourth edge of the wall, extending from the first section towards the first edge of the wall, c. a third section, substantially perpendicular to the vertical median plane, which extends from the second section towards the vertical median plane, d. a fourth section, substantially parallel to the vertical median plane and closer to it than the second section, which connects the third section and the first edge of the wall.

[0022] According to another feature, the first and second lateral parts are symmetrical with respect to a vertical median plane, the median cutout being positioned in the vertical median plane, the first and second lateral parts comprising first and second oblique folding lines symmetrical with respect to the vertical median plane and each forming with the latter an angle between 45 and 80°.

[0023] The invention also relates to an aircraft comprising at least one overpressure device according to one of the preceding characteristics.

[0024] 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:

[0025] [Fig-1] is a side view of an aircraft,

[0026] [Fig.2] is a perspective view of a secondary structure of an aircraft mast illustrating one method of implementation,

[0027] [Fig.3] is a perspective view of a pressure relief gate in the closed position illustrating a method of realizing earlier art,

[0028] [Fig.4] is a longitudinal section of the pressure relief gate visible in [Fig.3] in open position

[0029] [Fig.5] is a view from below of the overpressure gate visible in [Fig.3] in closed position

[0030] [Fig.6] is a perspective view, from an exterior area of ​​a structure secondary component of an aircraft mast, of a pressure relief device in the closed position illustrating one embodiment of the invention,

[0031] [Fig.7] is a bottom view of a pressure relief device in the closed position illustrating one embodiment of the invention,

[0032] [Fig.8] is a perspective view, from an interior area of ​​a secondary structure of an aircraft mast, of a pressure relief device illustrating one embodiment of the invention,

[0033] [Fig.9] is a perspective view illustrating a positioning holding system closed illustration of one embodiment of the invention,

[0034] [Fig. 10] is a section along line XX of [Fig. 9] of a system for holding in the closed position,

[0035] [Fig. 11] is a perspective view, from a first viewing angle, of a pressure relief device in the open position illustrating one embodiment of the invention,

[0036] [Fig. 12] is a perspective view, from a second viewing angle, of a pressure relief device in the open position illustrating one embodiment of the invention,

[0037] [Fig. 13] is a longitudinal section of a pressure relief device in the closed position illustrating another embodiment of the invention,

[0038] [Fig. 14] is a longitudinal section of a pressure relief device in the closed position illustrating another embodiment of the invention, and

[0039] [Fig. 15] is a longitudinal section of the overpressure device visible on [Fig. 14] in the open position.

[0040] According to an embodiment visible in figures 13 to 15, a fairing 32 separates an inner zone ZI positioned below the fairing 32 and an outer zone ZE positioned above the fairing 32. According to one application, the fairing 32 corresponds to a secondary structure of an aircraft mast.

[0041] The fairing 32 includes an opening 34 for communication between the inner and outer zones ZI and ZE, and a pressure relief device 36 comprising at least one wall 38 configured to occupy a closed position in which the wall 38 blocks the opening 34 and isolates the inner and outer zones ZI and ZE, and an open position in which the wall 38 at least partially exposes the opening 34, with the inner and outer zones ZI and ZE communicating with each other. The wall has an inner face F38 oriented towards the inner zone ZI and an outer face F38' oriented towards the outer zone ZE.

[0042] The wall 38 includes at least one movable part 42 relative to a fixed part 40. The overpressure device includes at least one joint 44 configured to connect at least one fixed part 40 and at least one movable part 42.

[0043] According to embodiments visible in figures 6 to 12, 14 and 15, the wall 38 comprises at least one fixed part 40 and each joint 44 comprises at least one folding line 46 connecting at least one fixed part 40 and at least one movable part 42.

[0044] According to a first embodiment visible in figures 6 to 12, at least one fixed part 40 of the wall 38 is connected by connecting elements 48.1 to 48.5, such as rivets for example, to a fixed element of the fairing 32. According to one configuration, for each fixed part 40 of the wall 38 considered, the connecting elements 48.1 to 48.5 are aligned and positioned approximately along the fold line 46 separating the fixed part 40 considered and the movable part 42 connected to the fixed part 40 considered.

[0045] According to a second embodiment visible in figures 14 and 15, the fixed part 40 of the wall 38 is connected by at least one connecting element 48 to a plate 50 integral with the fairing 32, positioned straddling the fixed part 40 and the fairing 32.

[0046] According to these first and second embodiments, the passage into the open position is obtained by plastic deformation of the wall 38 approximately along the folding line 46.

[0047] Of course, the invention is not limited to these embodiments for the joint 44. Thus, as illustrated in [Fig. 13], the joint 44 can be a hinge or at least a gooseneck substantially identical to those of the prior art. However, providing a joint in the form of at least one bend line 46 makes it possible to reduce the cost, size, and weight of the joint 46.

[0048] Regardless of the embodiment, during the transition from the closed position to the open position, each moving part 42 undergoes an opening movement Mo around a pivot axis. Depending on one configuration, the opening movement Mo corresponds approximately to a pivoting movement around the folding line 46.

[0049] The overpressure device 36 also includes at least one retaining system 54 configured to hold the wall 38 in the closed position. This retaining system 54 includes at least one fusible element 56 housed astride a first housing 58 integral with a first movable part 42 and a second housing 60 integral with a second movable part 42' or a fixed element.

[0050] In one configuration, the fusible element 56 is a cylindrical pin having an axis A56 substantially perpendicular to the opening movement Mo, parallel to the wall 38 (more particularly to its inner face F38). This pin has a substantially constant diameter along its entire length (dimension taken parallel to its axis A56). In addition, the first and second housings 58, 60 are also cylindrical and have a diameter substantially identical to that of the fusible pin 56.

[0051] According to one arrangement, the first and second housings 58, 60 open at the level of the first and second faces F58, F60, which are parallel to each other, in contact with each other or very slightly spaced apart, substantially parallel to the opening movement Mo. This arrangement makes it possible to obtain a rupture of the fusible element 56 by shear when the wall 38 tends to open due, for example, to a pressure exceeding a given value in the inner zone ZI.

[0052] The fusible element 56 has at least one characteristic chosen in particular from its cross-section or its material for example, configured so as to remain intact and not break when the pressure in the inner zone ZI is less than a given value and to break when the pressure in the inner zone ZI is greater than or equal to the given value.

[0053] According to embodiments shown in Figures 13 to 15, the wall 38 has a first edge 38.1 and a second edge 38.2 opposite the first edge 38.1, the first and second edges 38.1 and 38.2 being substantially parallel to each other. According to these embodiments, the hinge 44 is positioned at the first edge 38.1 and at least one fusible element 56 is positioned at the second edge 38.2. In the case of a pin, its axis A56 is oriented perpendicular to the second edge 38.2.

[0054] As illustrated in Figures 9 and 10, the retaining system 54 comprises a first L-shaped support 62 attached to the wall 38, having a first wing 62.1 pressed against the inner face F38 of the wall 38 and connected to it thus that a second wing 62.2 which has an opening through it (which forms the first housing 58 intended to partially house the fusible element 56), said opening leading to a first face F58 oriented towards the fairing 32, positioned approximately in line with the second edge 38.2. The retaining system 54 also includes a second L-shaped support 64, integral with the fairing 32, having a first wing 64.1 pressed against an inner face of the fairing 32 and connected to the latter, and a second wing 64.2 which has an opening through it (which forms the second housing 60 intended to partially house the fusible element 56) and leading to a second face F60 oriented towards the wall 38, positioned approximately in line with the second edge 38.2.

[0055] According to an embodiment visible in figures 6 to 12, the wall 38 has first and second edges 38.1, 38.2 substantially perpendicular to a vertical median plane PMV, the first edge 38.1 being oriented towards the front of the aircraft, as well as lateral edges 38.3, 38.4 connecting the first and second edges 38.1, 38.2, symmetrical with respect to the vertical median plane PMV.

[0056] According to one application, an aircraft includes at least one overpressure device 36 positioned on the top part of the secondary structure of a mast, the vertical median plane PMV of the wall 38 being coincident with the vertical median plane of the aircraft mast.

[0057] According to one configuration, the wall 38 comprises at least first and second lateral parts 66, 68 separated by a median cutout 70 positioned at the level of the vertical median plane PMV. According to this configuration, each of the first and second lateral parts 66, 68 comprises a hinge 44 positioned at the level of the third or fourth edge 38.3, 38.4 of the wall 38. The overpressure device comprises at least one retaining system 54 having at least one long, fusible element 56, positioned on either side of the median cutout 70 and oriented perpendicular to the median cutout 70. The retaining system 54 comprises: a.a first support 62, integral with the first lateral part 66 of the wall 38, having a first face F58 oriented towards the second lateral part 68 of the wall 38, positioned approximately in line with the median cutout 70 and at the level of which opens a first housing 58 provided for partially housing the fusible element 56 b. a second support 64, integral with the second lateral part 68 of the wall 38, having a second face F60 oriented towards the first lateral part 66 of the wall 38, positioned approximately in line with the median cutout 70 and at the level of which opens a second housing 60 provided for partially housing the fusible element 56. .

[0058] According to a configuration visible in figures 6 to 12, the wall 38 comprises first and second lateral parts 66, 68 positioned on either side of the vertical median plane PMV separated by a median cutout 70 and a central part 72 separated from the first lateral part 66 by a first cutout 74 and from the second lateral part 68 by a second cutout 76.

[0059] Cutting the wall 38 into several movable parts makes it possible to reduce the dimensions of the movable parts cantilevered relative to the fairing 32 and to eliminate the system for holding the movable parts in a half-open position.

[0060] The first cut 74 comprises a first section 74.1, substantially perpendicular to the vertical median plane PMV and spaced from the second edge 38.2 of the wall 38, which extends from the median cut 70 towards the third edge 38.3 of the wall 38; a second section 74.2, substantially parallel to the vertical median plane PMV and spaced from the third edge 38.3 of the wall 38, which extends from the first section 74.1 towards the first edge 38.1 of the wall 38; a third section 74.3 substantially perpendicular to the vertical median plane PMV, which extends from the second section 74.2 towards the vertical median plane PMV and a fourth section 74.4, substantially parallel to the vertical median plane PMV and closer to it than the second section 74.2, connecting the third section 74.3 and the first edge 38.1 of the wall 38.

[0061] The second cutout 76 comprises a first section 76.1, substantially perpendicular to the vertical median plane PMV and spaced from the second edge 38.2 of the wall 38, which extends from the median cutout 70 towards the fourth edge 38.4 of the wall 38; a second section 74.2, substantially parallel to the vertical median plane PMV and spaced from the fourth edge 38.4 of the wall 38, which extends from the first section 76.1 towards the first edge 38.1 of the wall 38; a third section 76.3, substantially perpendicular to the vertical median plane PMV, which extends from the second section 76.2 towards the vertical median plane PMV and a fourth section 76.4, substantially parallel to the vertical median plane PMV and closer to it than the second section 76.2, connecting the third section 76.3 and the first edge 38.1 of the wall 38.

[0062] According to one arrangement, the first and second lateral parts 66, 68 and the first and second cutouts 74, 76 are symmetrical with respect to the vertical median plane PMV. The second sections 74.2, 76.2 of the first and second cutouts 74, 76 have substantially equal lengths. The fourth sections 74.4, 76.4 have substantially equal lengths, less than one-third the length of the second sections 74.2, 76.2.

[0063] According to one embodiment, the central part 72 comprises at least one orifice 78 passing through it. According to one configuration, the central part 72 comprises several oblong orifices 78 (each of them being symmetrical with respect to the vertical median plane PMV) positioned between the second sections 74.2, 76.2 of the first and second cuts 74, 76.

[0064] The first lateral part 66 includes a hinge 44 in the form of a first oblique fold line 46 separating the first fixed and movable lateral parts 40, 42, the first fixed lateral part 40 being connected to a fairing element 32 by at least first and second connecting elements 48.1, 48.2 positioned on the first oblique fold line 46. According to one arrangement, the first connecting element 48.1 is positioned near an angle formed by the second and third edges 38.2, 38.3 of the wall 38. In addition, the second connecting element 48.2 is positioned near the first edge 38.1 of the wall 38, approximately in line with the second section 74.2 of the first cutout 74.

[0065] The second lateral part 68 includes a hinge 44' in the form of a second oblique fold line 46' separating the second fixed and movable lateral parts 40', 42', the second fixed lateral part 40' being connected to a fairing element 32 by at least three and four connecting elements 48.3, 48.4 positioned on the second oblique fold line 46'. According to one arrangement, the third connecting element 48.3 is positioned near an angle formed by the second and fourth edges 38.2, 38.4 of the wall 38. In addition, the fourth connecting element 48.2 is positioned near the first edge 38.1 of the wall 38, approximately in line with the second section 76.2 of the second cutout 76.

[0066] According to one arrangement, the first and second oblique folding lines 46, 46' are symmetrical with respect to the vertical median plane PMV and each form an angle between 45 and 80° with the latter.

[0067] The central part 72 includes an articulation 44”, in the form of a central folding line 46”, separating central fixed and movable parts 40”, 42”, the central fixed part 40' ' being connected to an element of the fairing 32 by at least a fifth connecting element 48.5 positioned on the central folding line 46”. The latter is oriented perpendicular to the vertical median plane PMV and located between the third sections 74.3, 76.3 and the first side 38.1.

[0068] According to the embodiment shown in Figures 6 to 12, the overpressure device 36 comprises at least a first retaining system 54 having at least a first long, fusible element 56, positioned on either side of the median cutout 70 and oriented perpendicular to the median cutout 70. The retaining system 54 also comprises a first support 62, integral with the first lateral part 66 of the wall 38, having a first face F58 oriented towards the second lateral part 68 of the wall 38, positioned approximately in line with of the median cutout 70 and at the level of which opens a first housing 58 intended to partially house the first fusible element 56 as well as a second support 64, integral with the second lateral part 68 of the wall 38, comprising a second face F60 oriented towards the first lateral part 66 of the wall 38, positioned approximately in the extension of the median cutout 70 and at the level of which opens a second housing 60 intended to partially house the first fusible element 56.

[0069] The overpressure device 36 includes at least a second retaining system 54' comprising at least a second long-line fusible element 56', positioned on either side of the second section 74.2 of the first cutout 74 and oriented perpendicularly to the second section 74.2 of the first cutout 74. This second retaining system 54' also includes a first support 62, integral with the first lateral part 66 of the wall 38, comprising a first face F58, oriented towards the central part 72 of the wall 38, positioned approximately in line with the second section 74.2 of the first cut 74 and at which a first housing 58 opens, intended to partially house the second fusible element 56' as well as a second support 64, integral with the central part 72 of the wall 38, comprising a second face F60 oriented towards the first lateral part 66 of the wall 38, positioned approximately in the extension of the second section 74.2 of the first cut 74 and at which a second housing 60 opens, intended to partially house the second fusible element 56'. .

[0070] The overpressure device 36 includes at least a third retaining system 54” comprising at least a third long-line fusible element 56”, positioned on either side of the second section 76.2 of the second cutout 76 and oriented perpendicularly to the second section 76.2 of the second cutout 76. This third retaining system 54” also includes a first support 62, integral with the second lateral part 68 of the wall 38 comprising a first face F58, oriented towards the central part 72 of the wall 38, positioned approximately in line with the second section 76.2 of the second cut 76 and at which a first housing 58 opens, intended to partially house the third fusible element 56” as well as a second support 64, integral with the central part 72 of the wall 38, comprising a second face F60 oriented towards the second lateral part 68 of the wall 38, positioned approximately in the extension of the second section 76.2 of the second cut 76 and at which a second housing 60 opens, intended to partially house the third pin 56”.

[0071] According to the embodiment visible in Figures 6 to 12, in the absence of pressure in the lower zone Zi or as long as the latter remains below a given value, the first and second lateral parts 66, 68 as well as the central part 72 are connected by the first, second and third fusible elements 56, 56', 56" and form a substantially continuous wall 38, as illustrated in Figures 6 to 8.

[0072] When the pressure in the inner zone ZI is equal to or greater than the given value, the latter causes shear forces at the first, second, and third fusible elements 56, 56', 56”, which rupture. The pressure in the inner zone ZI causes plastic deformation of the first and second lateral parts 66, 68 as well as the central part 72, causing the lateral and central moving parts 42, 42', 42” to pivot around the oblique and central bend lines 46, 46', 46”, as illustrated in Figures 11 and 12.

Claims

Demands

1. Overpressure device comprising at least one wall (38) configured to occupy a closed position in which the wall (38) closes an opening (34) and isolates inner and outer zones (ZI, ZE) positioned on either side of the wall (38), as well as an open position in which the wall (38) at least partially exposes the opening (34), the wall (38) comprising at least first and second movable parts (42, 42') relative to a fixed element, the overpressure device comprising at least one hinge (44) configured to connect each movable part (42, 42') to the fixed element and at least one holding system (54) configured to hold the wall (38) in the closed position as long as a pressure in the inner zone is less than a given value, each movable part (42,42') being animated by an opening movement (Mo) around a pivot axis during the transition from the closed position to the open position of the wall (38); characterized in that the retaining system (54) comprises at least one fusible element (56) housed astride a first housing (58) integral with a first movable part (42) and a second housing (60) integral with a second movable part (42'), the fusible element (56) being configured so as to remain intact when the pressure in the inner zone (ZI) is less than the given value and to rupture when the pressure in the inner zone (ZI) is greater than or equal to the given value.

2. Overpressure device according to claim 1, characterized in that the fusible element (56) is a pin having an axis (A56) oriented substantially perpendicular to the opening movement (Mo).

3. Overpressure device according to claim 1 or 2, characterized in that the first and second housings (58, 60) open at the level of first and second faces (F58, F60) parallel to each other, in contact with each other or very slightly spaced apart and substantially parallel to the opening movement (Mo).

4. Overpressure device according to any one of the preceding claims, characterized in that the wall (38) comprises at least one fixed part (40) and each joint (44) comprises at least one fold line (46) connecting at least one fixed part (40) and at least one movable part (42) of the wall (38), the passage in the position open being obtained by plastic deformation of the wall (38) approximately along the folding line (46).

5. Overpressure device according to the preceding claim, characterized in that at least one fixed part (40) of the wall (38) is connected by connecting elements (48.1 to 48.5) to a fixed element, the connecting elements (48.1 to 48.5) being aligned and positioned approximately along the fold line (46) separating the fixed part (40) and the moving part (42) connected to the fixed part (40).

6. Overpressure device according to any one of the preceding claims, characterized in that the wall (38) comprises at least first and second lateral parts (66, 68) separated by a median cutout (70) and in that the overpressure device comprises at least a first retaining system (54) comprising at least a first fusible element (56) positioned on either side of the median cutout (70).

7. Overpressure device according to the preceding claim, characterized in that the wall (38) comprises a central part (72), a first cutout (74) separating the central part (72) and the first lateral part (66) and a second cutout (76) separating the central part (72) and the second lateral part (68) and in that the overpressure device comprises at least one second retaining system (54') comprising at least one second fusible element (56') positioned on either side of the first cutout (74) and at least one third retaining system (54”) comprising at least one third fusible element (56”) positioned on either side of the second cutout (76).

8. Overpressure device according to the preceding claim, characterized in that the wall (38) comprises first and second edges (38.1, 38.2) substantially perpendicular to a vertical median plane (VMP) and lateral edges (38.3, 38.4), connecting the first and second edges (38.1, 38.2), symmetrical with respect to the vertical median plane (PMV) and in that each of the first and second cutouts (74, 76) comprises: a. a first section (74.1), substantially perpendicular to the vertical median plane (PMV) and spaced from the second edge (38.2) of the wall (38), which extends from the median cut (70) towards the third or fourth edge (38.3, 38.4) of the wall (38), b. a second section (74.2), substantially parallel to the vertical median plane (PMV) and spaced from the third or fourth edge (38.3, 38.4) of the wall (38), which extends from the first section (74.1) towards the first edge (38.1) of the wall (38), c. a third section (74.3), substantially perpendicular to the vertical median plane (VMP), which extends from the second section (74.2) in the direction of the vertical median plane (VMP), d. a fourth section (74.4), substantially parallel to the vertical median plane (PMV) and closer to it than the second section (74.2), which connects the third section (74.3) and the first edge (38.1) of the wall (38).

9. Overpressure device according to any one of claims 6 to 8, characterized in that the first and second lateral parts (66, 68) are symmetrical with respect to a vertical median plane (PMV), the median cutout (70) being positioned in the vertical median plane (PMV), and in that the first and second lateral parts (66, 68) comprise first and second oblique folding lines (46, 46') symmetrical with respect to the vertical median plane (PMV) and each forming with the latter an angle between 45 and 80°.

10. Aircraft comprising at least one overpressure device according to one of the preceding claims.