Propulsion system including a compact, high-mounted engine mount; aircraft including at least one such propulsion system

Abstract

Propulsion assembly including a compact high-mounted engine attachment, aircraft including at least one such propulsion assembly. The invention relates to a propulsion assembly including an engine and at least one engine attachment which connects the engine and a primary structure of a mast and includes a removable link (62) connecting a cross beam (60) and the primary structure.This detachable connection (62) comprises a first contact surface (F62) integral with the crossbeam (60), a second contact surface (F62') integral with the primary structure, at least one connecting element (78) holding the first and second contact surfaces (F62, F62') pressed against each other, at least one transverse force transmission system (74) between the motor and the primary structure, and at least one standby safety connection (80) separate from each connecting element (78) and configured to generate an additional force path only in the event of a malfunction of an element of the first detachable connection (62). This solution results in a motor mount that is compact in height. Figure 9.

Description

Title of the invention: Propulsion system comprising a compact, high-mounted engine mount; aircraft comprising at least one such propulsion system

[0001] The present application relates to a propulsion system comprising a compact, high-mounted engine attachment and to an aircraft comprising at least one such propulsion system.

[0002] According to an embodiment shown in Figures 1 and 2, an aircraft 10 comprises several propulsion units 12 positioned under each of the aircraft's wings 14. Each propulsion unit 12 comprises an engine 16, a nacelle (not shown in [Fig. 2]) positioned around the engine 16, and a mast 18 connecting the engine 16 and the wing 14.

[0003] As illustrated in [Fig.2], the engine 16 has a rotation axis A16 and includes a reactor core 20, a blower and a blower housing 22 which is approximately cylindrical in shape and in which the blower is positioned.

[0004] For the present application, a longitudinal direction X is parallel to the axis of rotation A16 of the engine 16, a transverse and horizontal direction Y is horizontal and perpendicular to the axis of rotation A16 of the engine 16, a vertical direction Z is vertical and perpendicular to the axis of rotation A16 of the engine 16. A transverse plane is perpendicular to the axis of rotation A16 of the engine 16. A vertical median plane PVM (visible in Figures 3 and 4) corresponds to a vertical plane passing through the axis of rotation A16 of the engine 16. The terms front and rear refer to the direction of gas flow in the engine 16, which flows from front to rear.

[0005] The mast 18 comprises a primary structure 24 connected to the engine 16 by an engine attachment system 26 and to the wing 14 by a wing attachment system 28 as well as a secondary structure 24' forming an aerodynamic envelope positioned above the primary structure 24.

[0006] According to an embodiment of the prior art visible in [Fig.2], the engine attachment system 26 includes, among other things, a front engine attachment 30 connecting the front end 24.1 of the primary structure 24 and the fan casing 22 and / or the reactor core 20.

[0007] According to an embodiment of the prior art described in document FR3098794 and visible in figures 3 and 4, the front engine attachment 30 comprises a transverse beam 32 fixed to the front end 24.1 of the primary structure 24, at least one first two-point shackle 34 positioned on a first side of the median plane vertical PMV and connected by a first articulation 34.1 to the cross beam 32 and by a second articulation 34.2 to the engine 16 (to the reactor core 20 or to the fan casing 22) as well as a second three-point shackle 36 positioned on a second side of the vertical PMV median plane and connected by first and second articulations 36.1, 36.2 to the cross beam 32 and by a third articulation 36.3 to the engine 16 (to the reactor core 20 or to the fan casing 22).

[0008] The cross beam 32 is connected to the front end 24.1 of the primary structure 24 by a removable link 38.

[0009] The cross beam 32 and the front end 24.1 of the primary structure 24 respectively have first and second contact surfaces F32, F24 held pressed against each other by means of the detachable joint 38. The latter comprises two cylindrical spigot-type tenons 40, 40', positioned on either side of the vertical median plane PMV and integral with the primary structure 24, as well as cylindrical recesses 42, 42', one for each cylindrical tenon 40, 40', configured to fit the cylindrical tenons 40, 40' and provided in the cross beam 32. These cylindrical tenons 40, 40' have axes substantially parallel to the longitudinal direction X. In addition, the detachable joint 38 comprises connecting elements 44.1, 44.2, 44.1', 44.2', such as bolts or screws, positioned on either side of the vertical median plane PMV, each with an axis parallel to the longitudinal direction. For each spigot-type cylindrical tenon 40, 40', the detachable connection 38 comprises a first connecting element 44.1, 44.1' offset downwards relative to the spigot-type cylindrical tenon 40, 40' and a second connecting element 44.2, 44.2' offset upwards relative to the cylindrical tenon 40, 40'. The connecting elements are configured to keep the first and second contact surfaces F24, F32 pressed against each other, but also to ensure the transmission of forces between the motor 16 and the primary structure 24, particularly in the event of breakage of one of the spigot-type cylindrical tenons 40, 40'.

[0010] This embodiment leads to a relatively large height footprint, which tends to move the secondary structure 24' away from the mast and the engine 16 and, ultimately, to impact the aerodynamic performance of the aircraft.

[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 a propulsion assembly comprising a. an engine, b. a mast that includes a primary structure having a front end, c. at least one engine attachment that connects the engine and the front end of the primary structure and includes a crossbeam, a first connection a detachable link connecting the crossbeam and the primary structure, as well as a second link connecting the crossbeam and the motor, d. the first detachable link comprising a first contact surface attached to the cross beam, a second contact surface attached to the primary structure, at least one linking element maintaining the first and second contact surfaces pressed against each other and at least one transverse force transmission system configured to ensure a transmission of forces, oriented essentially in a vertical direction, between the motor and the primary structure.

[0013] According to the invention, the first detachable link comprises at least one standby safety link separate from each linking element and configured to generate an additional force path only in the event of a malfunction of an element of the first detachable link.

[0014] By separating the connecting element(s) from the pending safety connection(s), it is possible to optimize them independently and limit their size in the vertical direction. This allows the secondary structure to be brought closer to the engine in order to optimize the aircraft's aerodynamic performance.

[0015] According to another feature, each pending safety connection comprises at least one first form integral with the transverse beam and raised relative to the first contact surface and at least one second form integral with the primary structure and raised relative to the second contact surface, the first and second forms cooperating with each other and having at least one spacing between them in the vertical direction.

[0016] According to another feature, the first shape is protruding with respect to the first contact surface, the second shape being recessed with respect to the second contact surface and configured to house the first shape.

[0017] According to another feature, the first shape includes a first trapezoidal contour which has upper and lower edges substantially parallel to each other and perpendicular to the vertical direction as well as oblique edges connecting the upper and lower edges.

[0018] According to another feature, the upper edge has a greater length than the lower edge.

[0019] According to another feature, the first shape is a rib following the first trapezoidal contour.

[0020] According to another feature, the second shape comprises a second approximately trapezoidal contour which includes upper and lower faces substantially parallel to each other and perpendicular to the vertical direction as well as oblique panels connecting the upper and lower panels, the upper and lower panels being spaced at a greater distance than that separating the upper and lower edges of the first form.

[0021] According to another feature, the first detachable link comprises two transverse force transmission systems positioned symmetrically with respect to a vertical median plane and a safety link in standby position positioned between the two transverse force transmission systems and located at the level of the vertical median plane.

[0022] According to another feature, the first detachable link comprises first and second extensions attached to the primary structure which extend on either side of the primary structure and each present a part of the second contact surface, a transverse force transmission system being positioned at the level of each of the first and second extensions.

[0023] According to another feature, the first detachable link comprises an end piece which has a tubular body fitted into the front end of the primary structure and connected to the primary structure, the tubular body delimiting the second hollow shape and having a terminal face which forms the second contact surface.

[0024] According to another feature, the tip comprises the first and second extensions, the tubular body and the first and second extensions forming a single piece.

[0025] The invention also relates to an aircraft comprising at least one propulsion assembly according to one of the preceding characteristics.

[0026] 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:

[0027] [Fig-1] is a side view of an aircraft,

[0028] [Fig.2] is a side view of an aircraft propulsion assembly without a nacelle illustrating a method of realizing earlier art,

[0029] [Fig.3] is a perspective view of a front engine mount illustrating a mode of realization of prior art,

[0030] [Fig.4] is a front view of a front engine mount illustrating a mode of realization of prior art,

[0031] [Fig.5] is a front view of a front engine mount illustrating a mode of realization of the invention,

[0032] [Fig.6] is a perspective view of a front engine mount, in the disassembled state, illustrating one embodiment of the invention,

[0033] [Fig.7] is a perspective view of a transverse beam of the motor mount before visible on [Fig.6],

[0034] [Fig-8] is a longitudinal section of part of a front engine mount illustrating one embodiment of the invention,

[0035] [Fig.9] is a schematic representation of the front motor attachment visible on [Fig.6] illustrating force paths.

[0036] According to one embodiment, an aircraft comprises at least one propulsion unit 50 positioned under a wing and connected to the wing. Each propulsion unit 50 comprises an engine 52 (shown schematically), a nacelle (not shown) positioned around the engine 52, and a mast 54 connecting the engine 52 to the wing.

[0037] The mast 54 comprises a primary structure 56 connected to the engine 52 by at least one engine attachment system and to the wing by at least one wing attachment system and a secondary structure 56' forming an aerodynamic envelope above the primary structure 56. The primary structure 56 has a front end 56.1 of the primary structure 56, an upper wall 56.2, a lower wall 56.3 and side walls 56.4, 56.5.

[0038] The motor attachment system includes at least one motor attachment 58 connecting in particular the front end 56.1 and the motor 52. Of course, the motor attachment system may include other motor attachments connecting the primary structure 56 and the motor 52.

[0039] According to one configuration, this motor attachment 58 is designed to ensure a transfer of forces, between the motor 52 and the primary structure 56, oriented in a transverse plane YZ (perpendicular to the longitudinal direction X).

[0040] This motor attachment 58 includes a cross beam 60, a first detachable link 62 connecting the cross beam 60 and the primary structure 56 and a second detachable link 64 connecting the cross beam 60 and the motor 52.

[0041] According to one embodiment, the second detachable link 64 comprises at least a first two-point shackle 66, positioned on a first side of the vertical median plane PMV and connected by a first hinge 66.1 to the cross beam 60 and by a second hinge 66.2 to the motor 52, as well as a second three-point shackle 68 positioned on a second side of the vertical median plane PMV and connected by first and second hinges 68.1, 68.2 to the cross beam 60 and by a third hinge 68.3 to the motor 52. According to one configuration, each of the first, second and third hinges 66.1, 66.2, 68.1, 68.2, 68.3 comprises a pivot axis substantially parallel to the longitudinal direction X.

[0042] The second detachable link 64 generally includes at least one waiting fail-safe link 70 of the "waiting fail-safe" type, connecting the crossbeam 60 and the motor 52, configured so as not to generate a force path when the crossbeam 60, the first and second shackles 66, 68 and the joints 66.1, 66.2, 68.1, 68.2, and 68.3 are functional and generate an additional load path only in the event of a failure of at least one element among the crossbeam 60, the first and second shackles 66 and 68, and the joints 66.1, 66.2, 68.1, 68.2, and 68.3. According to a first design shown in [Fig. 5], the second detachable connection 64 comprises a single waiting fail-safe connection 70 located at the vertical mid-plane PMV. According to a second design shown in Figures 6, 7, and 9, the second detachable connection 64 comprises two waiting fail-safe connections 70 and 70', symmetrical with respect to the vertical mid-plane PMV.

[0043] The second detachable link 64 is not described further because it may be identical to those of the prior art.

[0044] The cross beam 60 comprises a central part 60.1 positioned at least partially in line with the primary structure 56, and first and second branches 60.2, 60.3 positioned on either side of the central part 60.1 and connected respectively to the first and second shackles 66, 68. According to one configuration, each of the first and second branches 60.2, 60.3 comprises a clevis cooperating with the first or second shackle 66, 68. These first and second branches are not further described as they may be identical to those of the prior art.

[0045] The first detachable link 62 comprises a first contact surface F62 attached to the cross beam 60 and a second contact surface F62' attached to the primary structure 56, the first and second contact surfaces F62, F62' being pressed against each other and positioned approximately in transverse planes.

[0046] The first contact surface F62 corresponds to a rear face of the central part 60.1 of the transverse beam 60.

[0047] The first detachable joint 62 comprises at least one spigot-type tenon 72, integral with a first element from the primary structure 56 and the cross beam 60, and at least one housing 74 configured to accommodate the tenon 72 with a tight fit (without play in a transverse plane) and integral with a second element different from the first element from the primary structure 56 and the cross beam 60. Each of the tenons and housings 72, 74 has a lateral face substantially parallel to the longitudinal direction X. In one configuration, the tenons and housings 72, 74 are cylindrical and each has an axis of revolution substantially parallel to the longitudinal direction X. In one arrangement, each tenon 72 is integral with the cross beam 60 and each housing 74 is integral with the primary structure 56.Each tenon 72 protrudes from the first contact surface F62 and each housing 74 is recessed from the second contact surface F62'.

[0048] According to one arrangement, the first detachable link 62 comprises two pairs, each comprising a tenon 72 and a housing 74, positioned on either side of the vertical median plane PMV, preferably symmetrical with respect to the vertical median plane PMV.

[0049] In one configuration, the central portion 60.1 extends on either side of the lateral walls 56.4, 56.5 of the primary structure 56. Thus, the first contact surface F62 extends on either side of the lateral walls 56.4, 56.5 of the primary structure 56. In this configuration, the first detachable connection 62 comprises first and second extensions 76, integral with the primary structure 56, which extend on either side of the primary structure 56 and each present a portion of the second contact surface F62'. Thus, in operation, each of the first and second extensions 76 presents a face (corresponding to a portion of the second contact surface F62') in contact with a face (corresponding to a portion of the first contact surface F62) of the central portion 60.1 of the transverse beam 60.According to this configuration, each of the first and second extensions 76 includes a housing 74 configured to receive a tenon 72 attached to the crossbeam 60.

[0050] Of course, the invention is not limited to this configuration with regard to the number and arrangement of the tenon(s) 72 and the housing(s) 74. Regardless of the embodiment, the first detachable joint 62 comprises at least one transverse force transmission system configured to ensure the transmission of forces oriented essentially vertically (parallel to the vertical direction Z). By way of example, each transverse force transmission system comprises a pair consisting of a tenon 72 and a housing 74. According to a preferred arrangement, the first detachable joint 62 comprises two transverse force transmission systems positioned symmetrically with respect to the vertical median plane PMV.

[0051] The first detachable joint 62 comprises at least one connecting element 78 holding the first and second contact surfaces F62, F62' pressed against each other. In one embodiment, each connecting element 78 is a screw, a bolt, or a rivet and comprises a shank having an axis substantially parallel to the longitudinal direction X.

[0052] According to one configuration, the first detachable link 62 comprises several linking elements 78 positioned symmetrically with respect to the vertical median plane PMV and distributed around the periphery of the central part 60.1 of the transverse beam 60.

[0053] According to a particular feature of the invention, the connecting element(s) 78 is / are configured to ensure the transfer of forces along the longitudinal direction X in order to keep the first and second contact surfaces F62, F62' pressed together against each other and not shear forces in a transverse plane. Consequently, each connecting element 78 has a reduced cross-section (in a transverse plane) corresponding to a small footprint in the vertical or vertical direction.

[0054] The first detachable link 62 includes at least one waiting fail-safe link 80 configured not to generate load paths when no transverse load transmission system is damaged and to generate an additional load path taking up loads in a transverse plane, in particular vertical (oriented along the vertical direction Z) only in the event of a malfunction of an element of the first detachable link 62, in particular when at least one transverse load transmission system is defective and / or damaged, this waiting fail-safe link 80 being separate from each link element 78.

[0055] This standby safety link 80 is not configured to ensure that the first and second contact surfaces F62, F62' are held against each other.

[0056] According to an arrangement, each spare safety link 80 is positioned approximately at the same height as the transverse force transmission system(s) 72 / 74. In the presence of two transverse force transmission system(s) 72 / 74, the first removable link 62 includes a spare safety link 80 positioned between the two transverse force transmission system(s) 72 / 74 and located at the level of the vertical median plane PMV.

[0057] The fact that the safety link pending 80 is positioned between the two transverse force transmission system(s) and substantially at the same height as them allows for a small footprint in the vertical direction Z (in height).

[0058] According to one embodiment, each pending safety connection 80 comprises at least a first shape 82 integral with the transverse beam 60 and projecting from the first contact surface F62, and at least a second shape 84 integral with the primary structure 56 and projecting from the second contact surface F62', the first and second shapes 82, 84 cooperating with each other and having at least a spacing E between them in the vertical direction Z. According to a first variant, the first shape 82 projects from the first contact surface F62 and the second shape 84 is recessed from the second contact surface F62' and configured to house the first shape 82.According to a second variant, the first shape 82 is recessed relative to the first contact surface F62 and the second shape 84 is projecting relative to the second contact surface F62' and configured to fit into the first shape 82.

[0059] The spacing E is greater than 1 mm and on the order of a few millimeters.

[0060] According to one configuration, the first form 82 is an outgrowth and comprises a first trapezoidal contour having opposing upper and lower edges 86.1, 86.2, substantially parallel to each other and perpendicular to the vertical direction Z, as well as oblique edges 86.3, 86.4, connecting the upper and lower edges 86.1, 86.2, substantially symmetrical with respect to the vertical median plane PMV. According to one arrangement, the upper edge 86.1 has a length (distance measured along the transverse and horizontal direction Y) greater than that of the lower edge 86.2. According to one embodiment, the first form 82 is a rib 88, integral with the transverse beam 60 and projecting from the first contact surface F62, which follows the first trapezoidal contour.

[0061] In addition, the second form 84 includes a second approximately trapezoidal contour which includes upper and lower faces 90.1, 90.2 substantially parallel to each other and perpendicular to the vertical direction Z as well as oblique faces 90.3, 90.4 connecting the upper and lower faces 90.1, 90.2 and substantially symmetrical with respect to the vertical median plane PMV, the upper and lower faces 90.1, 90.2 being spaced at a distance greater than that separating the upper and lower edges 86.1, 86.2 of the first form 82. As illustrated in [Fig.8], the upper and lower faces 90.1, 90.2 are respectively substantially parallel to the upper and lower edges 86.1, 86.2 and spaced from the latter. Thus, the first detachable joint 62 includes a first spacing E between the upper edge and panel 86.1, 90.1 and a second spacing E' between the lower edge and panel 86.2, 90.2.

[0062] According to one embodiment, the first detachable link 62 comprises an end piece 92 which has a tubular body 92.1 fitted into the front end 56.1 of the primary structure 56, positioned between the upper, lower and lateral walls 56.2, 56.3, 56.4, 56.5 and connected to the primary structure 56, more particularly to at least one of the upper, lower and lateral walls 56.2, 56.3, 56.4, 56.5; this tubular body 92.1 delimiting the second hollow form 84 and having a terminal face which forms the second contact surface F62'. According to one configuration, the tip 92 includes first and second extensions 76 connected to the tubular body 92.1 at the level of each of which is positioned a transverse force transmission system 72 / 74, the tubular body 92.1 and the first and second extensions 76 forming only one and the same piece.

[0063] As illustrated in [Fig.8], when neither the cross beam 60 nor the transverse force transmission systems are damaged, the first and second forms 82, 84 are spaced apart along the vertical direction Z so that the standby safety link 80 does not form force paths between the motor 52 and the primary structure 56.

[0064] When the cross beam 60 has damage 94 between the standby safety link 80 and one of the transverse force transmission systems and / or one of the transverse force transmission systems has damage 96, the first and second forms 82, 84 are in contact with each other and the standby safety link 80 forms a force path between the motor 52 and the primary structure 56.

[0065] Unlike the prior art, the connecting element(s) 78 only ensure(s) that the first and second contact surfaces F62, F62' are held against each other and do not provide(s) the function of a temporary safety connection. Consequently, it has a reduced cross-section in a transverse plane.

[0066] Separating the connecting element(s) 78 and the pending safety connection(s) 80 allows each of them to be optimized and their height to be limited in the vertical direction Z. Thus, as illustrated in [Fig.5], it is possible to bring the secondary structure 56' closer to the engine 52 (unlike a secondary structure 98 of a mast of the prior art) in order to optimize the aerodynamic performance of the aircraft.

[0067] Providing a transverse force transmission system 72 / 74 at each of the extensions 76 allows the transverse force transmission systems 72 / 74 to be spaced as far apart as possible, favoring the positioning of a safety link 80 between said transverse force transmission systems 72 / 74.

Claims

Demands

1. Propulsion assembly comprising an engine (52), a mast (54) which includes a primary structure (56), having a front end (56.1), and at least one engine attachment (58) which connects the engine (52) and the front end (56.1) of the primary structure (56) and includes a crossbeam (60), a first detachable linkage (62) connecting the crossbeam (60) and the primary structure (56) and a second linkage (64) connecting the crossbeam (60) and the engine (52), the first detachable linkage (62) having a first contact surface (F62) integral with the crossbeam (60), a second contact surface (F62') integral with the primary structure (56), at least one connecting element (78) maintaining the first and second contact surfaces (F62, F62') pressed against each other and at least one force transmission system transverse (72 / 74) configured to ensure force transmission,oriented essentially along a vertical direction (Z), between the motor (52) and the primary structure (56); characterized in that the first detachable link (62) comprises at least one standby safety link (80) separate from each linking element (78) and configured to generate an additional load path only in the event of a malfunction of an element of the first detachable link (62).

2. Propulsion assembly according to the preceding claim, characterized in that each standby safety link (80) comprises at least one first form (82) integral with the cross beam (60) and in relief with respect to the first contact surface (F62) and at least one second form (84) integral with the primary structure (56) and in relief with respect to the second contact surface (F62'), the first and second forms (82, 84) cooperating with each other and having at least one spacing (E) between them in the vertical direction (Z).

3. Propulsion assembly according to the preceding claim, characterized in that the first form (82) is projecting relative to the first contact surface (F62) and in that the second form (84) is recessed relative to the second contact surface (F62') and configured to house the first form (82).

4. Propulsion assembly according to the preceding claim, characterized in that the first form (82) comprises a first trapezoidal contour which has upper and lower edges (86.1, 86.2) substantially parallel to each other and perpendicular to the vertical direction (Z) as well as oblique edges (86.3, 86.4) connecting the upper and lower edges (86.1, 86.2).

5. Propulsion assembly according to the preceding claim, characterized in that the upper edge (86.1) has a length greater than that of the lower edge (86.2).

6. Propulsion assembly according to any one of claims 4 to 5, characterized in that the first form (82) is a rib (88) following the first trapezoidal contour.

7. Propulsion assembly according to any one of claims 4 to 6, characterized in that the second form (84) comprises a second approximately trapezoidal contour which includes upper and lower faces (90.1, 90.2) substantially parallel to each other and perpendicular to the vertical direction (Z) and oblique faces (90.3, 90.4) connecting the upper and lower faces (90.1, 90.2), the upper and lower faces (90.1, 90.2) being spaced apart by a distance greater than that separating the upper and lower edges (86.1, 86.2) of the first form (82).

8. Propulsion assembly according to any one of the preceding claims, characterized in that the first detachable linkage (62) comprises two transverse force transmission systems (72 / 74) positioned symmetrically with respect to a vertical median plane (VMP) and a standby safety linkage (80) positioned between the two transverse force transmission systems (72 / 74) and located at the level of the vertical median plane (VMP).

9. Propulsion assembly according to any one of the preceding claims, characterized in that the first detachable link (62) comprises first and second extensions (76), integral with the primary structure (56), which extend on either side of the primary structure (56) and each present a part of the second contact surface (F62'), a transverse force transmission system (72 / 74) being positioned at the level of each of the first and second extensions (76).

10. Propulsion assembly according to any one of the preceding claims, characterized in that the first detachable linkage (62) comprises an end piece (92) which has a tubular body (92.1) fitted into the front end (56.1) of the primary structure (56) and connected to the primary structure (56), the tubular body (92.1) delimiting the second hollow form (84) and having a terminal face which forms the second contact surface (F62').

11. Propulsion assembly according to claims 9 and 10, characterized in that the tip (92) comprises the first and second extensions (76), the tubular body (92.1) and the first and second extensions (76) forming a single piece.

12. Aircraft comprising at least one propulsion assembly according to one of the preceding claims.