Aircraft propulsion system comprising an engine mounting system equipped with a longitudinal beam attached to an engine casing; aircraft comprising at least one such propulsion system

Abstract

Aircraft propulsion assembly comprising an engine mounting system equipped with a longitudinal beam integral with an engine casing, aircraft comprising at least one such propulsion assembly. The invention relates to a propulsion assembly comprising a forward engine mounting system (52) which connects an engine casing (50) of the engine to a primary structure (46) of the mast (44) and comprises at least one longitudinal beam (56) oriented along the longitudinal direction (X), first and second links (58, 60) spaced along the longitudinal direction (X), each connecting the longitudinal beam (56) and the engine casing (50), as well as a third link (62) connecting the longitudinal beam (56) and the primary structure (46). The invention also relates to an aircraft comprising at least one such propulsion assembly and a method for assembling such a propulsion assembly. Figure 3

Description

Title of the invention: Aircraft propulsion assembly comprising an engine mounting system equipped with a longitudinal beam integral with an engine casing; aircraft comprising at least one such propulsion assembly

[0001] The present application relates to an aircraft propulsion system comprising an engine mounting system equipped with a longitudinal beam attached to an engine casing 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 the wings 14 of the aircraft. Each propulsion unit 12 comprises a motor 16, a nacelle (not shown in [Fig. 2]) positioned around the motor 16, and a mast 18 connecting the motor 16 and the wing 14. The mast 18 comprises a primary structure 20 which is connected to the motor 16 by a motor attachment system 22 and to the wing 14 by a wing attachment system.

[0003] For the present invention, a longitudinal direction X is substantially parallel to the axis of rotation A16 of the motor 16. A horizontal transverse direction Y is a horizontal direction perpendicular to the axis of rotation A16. A vertical direction is denoted Z. The terms front / rear refer to the direction of flow of the fluids in the motor 16, which flow from front to rear.

[0004] According to an embodiment visible in [Fig. 2], the engine 16 comprises at least one engine casing 24 which extends along the longitudinal direction X and has an axis parallel to the longitudinal direction X. According to a configuration visible in [Fig. 2], the engine 16 comprises a single engine casing 24. According to another configuration, the engine 16 comprises a fan positioned in a fan casing as well as a reactor core which has an engine casing.

[0005] The motor mounting system 22 comprises a front motor mounting system 26 and a rear motor mounting system 28. According to a configuration shown in [Fig. 2], the front motor mounting system 26 connects a front end 20.1 of the primary structure 20 and a front section 24.1 of the motor housing 24. The rear motor mounting system 28 connects a mid-section 20.2 of the primary structure 20 and a mid-section 24.2 of the motor housing 24. In one embodiment, the front motor mounting system 26 is configured to transmit forces in a vertical direction Z and a horizontal transverse direction Y between the motor 16 and the primary structure 20.

[0006] According to another configuration, the front engine attachment system 26 connects a front end 20.1 of the primary structure 20 and the fan housing of the engine 16. In addition, the rear engine attachment system 28 connects a mid-zone of the primary structure 20 and the reactor core of the engine 16.

[0007] Regardless of the configuration, the mast 18 includes a fairing which covers the primary structure 20 and has an aerodynamic profile configured to limit the drag of the aircraft.

[0008] According to one assembly method, the motor 16 is connected to the primary structure 20 last, after the mast fairing 18 has been put in place.

[0009] Insofar as the mast fairing 18 has an aerodynamic profile, the forward engine attachment system 26 is positioned in a cramped or cluttered area making it difficult to mount the engine 16.

[0010] The present invention aims to remedy all or part of the drawbacks of the prior art.

[0011] To this end, the invention relates to a propulsion assembly comprising a motor which has at least one axis of rotation parallel to a longitudinal direction and at least one motor housing, a nacelle positioned around the motor, a mast which has a primary structure and at least one aerodynamic fairing, as well as a motor attachment system which connects the primary structure and the motor housing and comprises a front motor attachment system and a rear motor attachment system offset towards the rear in the longitudinal direction relative to the front motor attachment system.

[0012] According to the invention, the front engine attachment system comprises at least one longitudinal beam oriented along the longitudinal direction, first and second links spaced along the longitudinal direction, each connecting the longitudinal beam and the engine casing, and a third link connecting the longitudinal beam and the primary structure.

[0013] Even though the first linkage is positioned in substantially the same area as a prior art forward engine mounting system, it is installed before the engine is attached to the primary mast structure. Consequently, its installation is not problematic. Since the third linkage is offset rearward relative to the location of the prior art forward engine mounting system, it is positioned in a less confined or less cluttered area, which helps to facilitate its installation.

[0014] According to another feature, the third link comprises a pivoting link which has a pivot axis parallel to the longitudinal direction, located at the front of the primary structure, in the extension of the latter.

[0015] According to another feature, the third link comprises a cylinder attached to a first element from the primary structure and the longitudinal beam and a housing attached to a second element different from the first element from the primary structure and the longitudinal beam, the cylinder having an axis coinciding with the pivot axis, the cylinder and the housing being configured to allow the cylinder to pivot in the housing about the pivot axis.

[0016] According to another feature, the third connection comprises a bracket which has a base plated against the longitudinal beam and rigidly connected to the latter, a transverse wing attached to the base plate and positioned in a transverse plane perpendicular to the longitudinal direction, and a sleeve supported by the transverse wing, forming the housing.

[0017] According to another feature, the third bond comprises: a. at least one transverse connecting plate, approximately triangular, which has three vertices as well as first, second and third openings at the three vertices, the first opening forming the housing for the cylinder, b. the first and second connecting axes housed respectively in the second and third orifices, c. at least one screed attached to the longitudinal beam, supporting the connecting axes.

[0018] According to another feature, the longitudinal beam extends between front and rear ends. In addition, the first connection includes at least one lug attached to the engine casing and positioned in a transverse plane, as well as, for each lug, a connecting axis linking each lug and the front end of the longitudinal beam, the second connection including at least one lug attached to the engine casing and positioned in a transverse plane, as well as, for each lug, a connecting axis linking each lug and the rear end of the longitudinal beam.

[0019] According to another feature, each of the first and second links comprises two legs positioned in the same transverse plane and two connecting axes linking the two legs to the longitudinal beam.

[0020] According to another feature, the longitudinal beam comprises a longitudinal web positioned in a longitudinal and vertical plane, upper and lower flanges positioned on either side of the longitudinal web, front and rear end walls positioned in transverse planes at the front and rear ends of the longitudinal beam, and transverse ribs positioned in transverse planes connecting the longitudinal web and the upper and lower flanges.

[0021] The invention also relates to an aircraft comprising at least one propulsion system according to one of the preceding characteristics.

[0022] The invention also relates to a method of assembling a propulsion unit according to one of the preceding characteristics, which includes a first step of assembling the longitudinal beam consisting of connecting it to the engine casing by means of the first and second links and then a second step of assembling the motorization consisting of connecting it to the primary structure of the mast by means of the third link.

[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 schematic representation of a propulsion assembly illustrating an embodiment of the prior art,

[0026] [Fig.3] is a schematic representation of a propulsion assembly illustrating one embodiment of the invention,

[0027] [Fig.4] is a perspective view of a propulsion assembly (without fairing) illustrating a first embodiment of the invention,

[0028] [Fig.5] is a perspective view of a propulsion assembly (without fairing) illustrating a second embodiment of the invention.

[0029] According to an embodiment shown in [Fig. 3], an aircraft propulsion system 40 comprises an engine 42, a nacelle (not shown in [Fig. 3]) positioned around the engine 42, and a mast 44 connecting the engine 42 to an aircraft structure such as a wing. The mast 44 comprises a primary structure 46 connected to the engine 42 by an engine mounting system 48.

[0030] In one configuration, the engine 42 is a turbofan engine. In another configuration, the engine is a turboprop engine. Regardless of the configuration, the engine 42 has at least one axis of rotation parallel to a longitudinal direction X and includes a generally tubular engine casing 50, which extends along the longitudinal direction X.

[0031] The engine mounting system 48 comprises a front engine mounting system 52 and a rear engine mounting system 54 offset rearward relative to the front engine mounting system 52. According to a configuration visible in [Fig. 3], the front engine mounting system 52 connects the engine housing 50 of the engine 42 and a first zone 46.1 of the primary structure 46, located at the front end of the primary structure 46. In addition, the rear engine mounting system 54 connects a central section 50M of the engine housing 50 of the engine 42 and a second zone 46.2 of the primary structure 46, offset towards the rear with respect to the first zone 46.1.

[0032] The mast 44 also includes at least one fairing (not shown) which covers the primary structure 20 and has an aerodynamic profile configured to limit the drag of the aircraft.

[0033] The motor 42, the nacelle, the primary structure 20, the rear motor attachment system 54 are not described further as they may be substantially identical to those of the prior art.

[0034] The front engine attachment system 52 includes at least one longitudinal beam 56 oriented along the longitudinal direction X, first and second links 58, 60 spaced along the longitudinal direction X, each connecting the longitudinal beam 56 and the engine casing 50, and a third link 62 connecting the longitudinal beam 56 and the first zone 46.1 of the primary structure 46.

[0035] This longitudinal beam 56 extends between front and rear ends 56.1, 56.2.

[0036] According to an embodiment visible on 1 [Fig.3], this longitudinal beam 56 comprises a longitudinal web 64.1 positioned in a longitudinal and vertical plane XZ, upper and lower flanges 64.2, 64.3 positioned in horizontal and longitudinal planes XY on either side of the longitudinal web 64.1, front and rear end walls 64.4, 64.5 positioned in transverse planes YZ at the front and rear ends 56.1, 56.2 as well as transverse ribs 64.6 positioned in transverse planes YZ connecting the longitudinal web 64.1 and the upper and lower flanges 64.2, 64.3.

[0037] Of course, the invention is not limited to this embodiment for the longitudinal beam 56. Whatever the embodiment, the longitudinal beam 56 is a separate element from the engine casing 50, which is rigid between its front and rear ends 56.1, 56.2, and hardly deforms in bending.

[0038] According to a first configuration, the first and second links 58, 60 are configured to ensure a hyperstatic link between the longitudinal beam 56 and the engine casing 50.

[0039] According to embodiments visible in figures 4 and 5, the first linkage 58 comprises first and second lugs 58.1, 58.1' attached to the engine casing 50 and positioned in the same transverse plane YZ, as well as first and second linkage axes 58.2, 58.2' connecting respectively the first and second lugs 58.1, 58.1' and the front end 56.1 of the longitudinal beam 56 (more particularly the front end wall 64.4).

[0040] In addition, the second linkage 60 comprises first and second lugs 60.1 integral with the engine casing 50 and positioned in the same transverse plane YZ, as well as first and second connecting shafts 60.2 respectively linking the first and second legs 60.1 and the rear end 56.2 of the longitudinal beam 56 (more specifically the rear end wall 64.5).

[0041] According to a second configuration, the first and second links 58, 60 are configured to provide an isostatic connection between the longitudinal beam 56 and the engine casing 50. The first link 58 comprises a single tab attached to the engine casing 50, positioned in a transverse plane YZ, and a connecting pin linking the tab and the front end 56.1 of the longitudinal beam 56 (more specifically, the front end wall 64.4). The connecting pin forms a pivoting joint that can optionally be ball-jointed. In addition, the second link 60 comprises a single tab attached to the engine casing 50 and positioned in a transverse plane, and a connecting pin linking the tab and the rear end 56.2 of the longitudinal beam 56 (more specifically, the rear end wall 64.5). The connecting pin forms a pivoting joint that can optionally be ball-jointed.

[0042] Of course, the invention is not limited to these configurations for the first and second links 58, 60. Whatever the configuration, the first and second links 58, 60 make it possible to obtain a rigid link between the longitudinal beam 56 and the motorization 42 (more particularly the motor housing 50).

[0043] The third link 62 is configured to ensure a transmission of forces between the longitudinal beam 56 and the primary structure 46, oriented at least along the transverse and horizontal direction Y and the vertical direction Z.

[0044] According to a configuration visible in [Fig. 3], the third link 62 comprises a pivot joint having a pivot axis A62 parallel to the longitudinal direction X, located at the front of the primary structure 46, in line with the latter. Thus, the third link 62 comprises a cylinder 66 fixed to a first element of the primary structure 46 and the longitudinal beam 56, and a housing 68 fixed to a second element, different from the first element, of the primary structure 46 and the longitudinal beam 56. The cylinder 66 has an axis coinciding with the pivot axis A62, and the cylinder 66 and the housing 68 are configured to allow the cylinder 66 to pivot within the housing 68 about the pivot axis A62.

[0045] According to a first embodiment shown in [Fig. 4], the cylinder 66 is integral with the primary structure 46, the housing 68 being a sleeve 68.1 integral with the longitudinal beam 56. In addition, the third connection 62 comprises a bracket 70 which has a flange 70.1 pressed against the longitudinal beam 56 and rigidly connected to it by bolting, for example, as well as a transverse wing 70.2 positioned in a transverse plane YZ, integral with the flange 70.1 and supporting the sleeve 68.1. The bracket 70 may include at least one reinforcement 70.3 positioned in a vertical longitudinal plane XZ, connecting the flange 70.1 and the wing transversal 70.2. According to this first embodiment, the sleeve 68.1, the base 70.1, the transverse wing 70.2 and the reinforcement(s) 70.3 form a single piece.

[0046] According to a second embodiment shown in [Fig. 5], the cylinder 66 is integral with the primary structure 46. In addition, the third connection 62 comprises: a. at least one approximately triangular transverse junction plate 72, which has three rounded vertices and first, second and third openings 72.1, 72.2, 72.3 at the three vertices, the first opening 72.1 forming the housing 68 for the cylinder 66, b. of the first and second connecting axes 74.1, 74.2 housed respectively in the second and third orifices 72.2, 72.3, c. at least one slab 76 attached to the longitudinal beam 56, supporting the first and second connecting axes 74.1, 74.2.

[0047] Of course, the invention is not limited to these embodiments for the third link 62.

[0048] According to one assembly method, a method for assembling the motor 42 includes a first step of assembling the longitudinal beam 56 consisting of connecting it to the motor housing 50 by means of the first and second links 58, 60 and then a second step of assembling the motor 42 consisting of connecting it to the primary structure 46 of the mast 44 by means of the third link 62.

[0049] According to the invention, the first linkage 58 is positioned substantially in the same area as a prior art front motor mounting system. However, since the first linkage 58 is installed before the motor 42 is attached to the primary structure 46, this is not problematic. As the third linkage 62 is offset rearward relative to the location of the prior art front motor mounting system, the third linkage 62 is positioned in a less cramped or less congested area, which helps to facilitate its installation.

Claims

Demands

1. Propulsion assembly comprising an engine (42) which has at least one axis of rotation parallel to a longitudinal direction (X) and at least one engine casing (50), a nacelle positioned around the engine (42), a mast (44) which has a primary structure (46) and at least one aerodynamic fairing, and an engine attachment system (48) which connects the primary structure (46) and the engine casing (50) and comprises a front engine attachment system (52) and a rear engine attachment system (54) offset rearward along the longitudinal direction (X) relative to the front engine attachment system (52);characterized in that the front engine attachment system (52) comprises at least one longitudinal beam (56) oriented along the longitudinal direction (X), first and second links (58, 60) spaced along the longitudinal direction (X), each connecting the longitudinal beam (56) and the engine casing (50), and a third link (62) connecting the longitudinal beam (56) and the primary structure (46).

2. Propulsion assembly according to the preceding claim, characterized in that the third link (62) comprises a pivoting link which has a pivot axis (A62) parallel to the longitudinal direction (X), located at the front of the primary structure (46), in the extension of the latter.

3. Propulsion assembly according to the preceding claim, characterized in that the third link (62) comprises a cylinder (66) integral with a first element from the primary structure (46) and the longitudinal beam (56) and a housing (68) integral with a second element different from the first element from the primary structure (46) and the longitudinal beam (56), the cylinder (66) having an axis coinciding with the pivot axis (A62), the cylinder (66) and the housing (68) being configured to allow the cylinder (66) to pivot in the housing (68) about the pivot axis (A62).

4. Propulsion assembly according to the preceding claim, characterized in that the cylinder (66) is integral with the primary structure (46) and in that the third connection (62) comprises a bracket (70) having a base (70.1) pressed against the longitudinal beam (56) and rigidly connected thereto, a wing transverse (70.2) integral with the sole (70.1) and positioned in a transverse plane (YZ) perpendicular to the longitudinal direction (X), as well as a sleeve (68.1) supported by the transverse wing (70.2), forming the housing (68).

5. Propulsion assembly according to claim 3, characterized in that the cylinder (66) is integral with the primary structure (46) and in that the third connection (62) comprises: a. at least one transverse connecting plate (72), approximately triangular, which has three vertices as well as first, second and third orifices (72.1, 72.2, 72.3) at the level of the three vertices, the first orifice (72.1) forming the housing (68) for the cylinder (66), b. first and second connecting axes (74.1, 74.2) housed respectively in the second and third orifices (72.2, 72.3), c. at least one clevis (76) integral with the longitudinal beam (56), supporting the connecting axes (74.1, 74.2).

6. A propulsion assembly according to any one of the preceding claims, characterized in that the longitudinal beam (56) extends between front and rear extremities (56.1, 56.2), in that the first linkage (58) comprises at least one lug (58.1, 58.1') integral with the engine casing (50) and positioned in a transverse plane (YZ), and, for each lug (58.1, 58.1'), a connecting shaft (58.2, 58.2') linking each lug (58.1, 58.1') and the front end (56.1) of the longitudinal beam (56), and in that the second linkage (60) comprises at least one lug (60.1) integral with the engine casing (50) and positioned in a transverse plane (YZ), and, for each lug (60.1), a connecting shaft (60.2) linking each lug (60.1) and the rear end (56.2) of the longitudinal beam (56).

7. Propulsion assembly according to the preceding claim, characterized in that each of the first and second links (58) comprises two lugs (58.1, 58.1', 60.1) positioned in the same transverse plane (YZ) and two connecting axes (58.2, 58.2', 60.2) connecting the two lugs (58.1, 58.1', 60.1) to the longitudinal beam (56).

8. Propulsion assembly according to any one of the preceding claims, characterized in that the longitudinal beam (56) comprises a

9.

10. longitudinal web (64.1) positioned in a longitudinal and vertical plane (XZ), upper and lower flanges (64.2, 64.3) positioned on either side of the longitudinal web (64.1), front and rear end walls (64.4, 64.5) positioned in transverse planes (YZ) at the front and rear ends (56.1, 56.2) of the longitudinal beam (56) and transverse ribs (64.6) positioned in transverse planes (YZ) connecting the longitudinal web (64.1) and the upper and lower flanges (64.2, 64.3). Aircraft comprising at least one propulsion system according to one of the preceding claims. Method of assembling a propulsion unit according to any one of claims 1 to 8, characterized in that the assembly method comprises a first step of assembling the longitudinal beam (56) consisting of connecting it to the engine casing (50) by means of the first and second links (58, 60) and then a second step of assembling the motorization (42) consisting of connecting it to the primary structure (46) of the mast (44) by means of the third link (62).

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