AIRCRAFT PROPELLER ASSEMBLY COMPRISING A TURBOJET ENGINE, A MAST AND MEANS OF ATTACHING THE TURBOJET ENGINE TO THE MAST
The propulsion assembly with converging connecting rods and a hyperstatic system addresses the stress issue in turbojet engine attachments, ensuring reduced stresses and enhanced stability.
Patent Information
- Authority / Receiving Office
- FR · FR
- Patent Type
- Applications
- Current Assignee / Owner
- AIRBUS OPERATIONS (SAS)
- Filing Date
- 2024-12-23
- Publication Date
- 2026-06-26
AI Technical Summary
Existing turbojet engine attachment systems experience significant stresses between the turbojet, the attachment mast, and the wing, necessitating a solution to minimize these forces.
A propulsion assembly comprising a turbojet engine, a mast, and a hooking device with specific connecting rods and clevis joints that minimize stresses by converging inner connecting rods towards the turbojet's axis of rotation, utilizing a hyperstatic system for enhanced stability.
The proposed arrangement reduces stresses and ensures safety by distributing forces effectively, providing a stable attachment system even in the event of a connecting rod failure.
Smart Images
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Abstract
Description
Title of the invention: PROPULSION ASSEMBLY FOR AN AIRCRAFT COMPRISING A TURBOJET ENGINE, A MAST AND MEANS FOR ATTACHING THE TURBOJET ENGINE TO THE MAST technical field
[0001] The present invention relates to the general field of attaching a turbojet engine under the wing of an aircraft. It relates in particular to a propulsion system comprising a turbojet engine, for example of the unfaired fan type, a pylon, and a mounting system for attaching the turbojet engine under the pylon. It also relates to an aircraft equipped with such a propulsion system. PREVIOUS STATE OF THE ART
[0002] An aircraft conventionally comprises wings and at least one propulsion unit fixed under each of these wings. Each propulsion unit includes a pylon and an engine. The pylon has a rigid structure called the "primary structure" which is fixed between the wing and the engine by means of attachment assemblies, namely a first attachment assembly between the wing and the pylon and a second attachment assembly between the pylon and the engine.
[0003] Although such an engine assembly is efficient, the evolution of turbojets leads to the need to develop attachment masts which, among other things, minimize the stresses between the turbojet, the attachment mast and the wing. Description of the invention
[0004] An object of the present invention is to propose a propulsion assembly comprising a turbojet, a mast and a hooking device for hooking the turbojet under the mast, and which allows minimizing the forces.
[0005] To this end, a propulsion system for an aircraft is proposed, said propulsion system having a longitudinal axis and a vertical median plane passing through the longitudinal axis and comprising:
[0006] - a turbojet engine comprising a front casing with a rear face perpendicular to the longitudinal axis and a rear casing, where the longitudinal axis constitutes an axis of rotation of the turbojet,
[0007] - a rigging mast having a primary structure with a lower spar,
[0008] - two external connecting rods arranged on either side of the median plane, where each The outer connecting rod has a rear end mounted and hinged to the lower side member by a first rear connection point, and a front end mounted and hinged to the rear face by a first front connection point, and
[0009] - two internal connecting rods arranged on either side of the median plane, where each The inner connecting rod has a rear end mounted articulated to the lower side member by a second rear connection point and a front end mounted articulated to the rear face or rear casing by a second front connection point and where the axes of the inner connecting rods converge towards the longitudinal axis.
[0010] With such an arrangement, the proximity of the inner connecting rods on the rear casing and the convergence of the axes of the inner connecting rods on the longitudinal axis minimize the stresses.
[0011] Advantageously, the propulsion assembly further comprises a propeller at the front of the front casing and convergence on the longitudinal axis takes place at the center of the propeller.
[0012] Advantageously, the front connection points of the outer connecting rods are aligned along a horizontal transverse line.
[0013] Advantageously, each connection point of the external connecting rods takes the form of a pivot joint whose axis is perpendicular to the median plane.
[0014] Advantageously, the propulsion assembly includes an engine attachment between a front wall of the primary structure and the front casing.
[0015] Advantageously, the motor attachment comprises a female clevis attached to the front wall, a male clevis attached to the rear face and mounted articulated in the female clevis, a pin attached to the primary structure and whose axis is parallel to the longitudinal axis and a housing in the rear face in which the pin is housed.
[0016] Advantageously, the screeds, the pin and the housing are arranged at the level of the median plane.
[0017] Advantageously, the pin is integral with the lower spar.
[0018] Advantageously, each second rear connection point is fixed to the lower spar by means of a beam integral with the lower spar and extending laterally from the primary structure.
[0019] The invention also proposes an aircraft comprising a wing and a propulsion assembly according to one of the preceding variants, the primary structure of which is fixed under the wing. Brief description of the drawings
[0020] The features of the invention mentioned above, as well as others, will become clearer upon reading the following description of an exemplary embodiment, said description being made in relation to the accompanying drawings, among which:
[0021] [Fig-1] represents a side view of an aircraft according to the invention,
[0022] [Fig.2] is a schematic representation of a propulsion assembly according to the invention in side view, and
[0023] [Fig.3] is a perspective view of a propulsion assembly according to the invention.
[0024] DETAILED STATEMENT OF IMPROVEMENTS
[0025] With reference to [Fig.1], an aircraft 50 comprises a fuselage 51 to which is fixed, on each side, a wing 52 under which is mounted at least one propulsion assembly 100 according to the invention.
[0026] The propulsion assembly 100 includes a mounting mast 104 fixed under the wing 52 and a turbojet 102 fixed under the mounting mast 104. The turbojet 102 is of the unfaired fan turbojet type.
[0027] By convention, X is called the longitudinal axis of the turbojet 102 and therefore of the propulsion assembly 100, this longitudinal axis X being parallel to a longitudinal direction of this turbojet 102. On the other hand, Y is called the transverse axis of the turbojet 102 which is horizontal when the aircraft is on the ground, and Z is called the vertical axis or vertical height when the aircraft is on the ground, these three directions X, Y and Z being orthogonal to each other.
[0028] On the other hand, the terms "forward" and "rear" are to be considered in relation to a direction of advance of the aircraft 50 during the operation of the turbojet 102, this direction being schematically represented by the arrow 107 on the [Fig.1].
[0029] Fig. 2 and Fig. 3 show the propulsion assembly 100 according to the invention.
[0030] The turbojet 102 comprises, from front to rear, a propeller 53, a nacelle 54 in which the other elements of the turbojet 102 are housed, and which takes the form of a core having a front casing 112a and a rear casing 112b, which is fixed to the rear of the front casing 112a and in which the other elements of the turbojet 102 are housed, such as compression stages, a combustion chamber, turbine stages, and an exhaust cone. The rear casing 112b and the front casing 112a are coaxial with the longitudinal axis X, and the rear casing 112a has a smaller diameter than the front casing 112a. The rear casing 112b extends here from a rear face 113 of the front casing 112a which is perpendicular to the longitudinal axis X which constitutes an axis of rotation of the turbojet 102.
[0031] The attachment mast 104 is represented here by its primary structure 106 which is fixed to the wing structure 52 by all appropriate fastening means known to a person skilled in the art.
[0032] The primary structure 106 is in the form of a box extending along the longitudinal direction X and comprising a front wall 106e, located at the front of the primary structure 106, a lower spar 106a extending below the primary structure 106, and an upper spar 106b extending above the primary structure 106. The primary structure 106 also comprises two walls lateral 106c-d on each side of the vertical median plane P. These different stringers and walls are fixed to each other to form the primary structure 106.
[0033] The mooring mast 104 and the turbojet 102 are globally symmetrical with respect to a vertical median plane XZ of the propulsion assembly 100 which passes through the longitudinal axis X, which is hereafter called the median plane P and which separates the mooring mast 104 and the turbojet 102 into two port-starboard parts.
[0034] The propulsion assembly 100 also includes two external connecting rods 120 which are arranged on either side of the median plane P. Each external connecting rod 120 has a rear end 120a which is mounted articulated to the lower longitudinal member 106a by a first rear connection point 121a and a front end 120b which is mounted articulated to the rear face 113 of the front housing 112a by a first front connection point 121b.
[0035] Similarly, the propulsion assembly 100 also includes two inner connecting rods 122 which are arranged on either side of the median plane P. Each inner connecting rod 122 has a rear end 122a which is mounted articulated to the lower longitudinal member 106a by a second rear connection point 123a and a front end 122b which is mounted articulated to the rear face 113 or to the rear casing 112b by a second front connection point 123b.
[0036] The inner connecting rods 122 are located inside the propulsion assembly 100 relative to the outer connecting rods 120, which are on the outside of the inner connecting rods 122 and extend further back relative to the inner connecting rods 122.
[0037] The second rear connection point 123a is arranged in front of the first rear connection point 121a.
[0038] Furthermore, the axes of the inner connecting rods 122 converge towards the longitudinal axis X. The axis of a connecting rod is the axis connecting the two ends of the connecting rod and is represented here by the reference 'd' in [Fig. 3]. According to a preferred embodiment, the convergence on the longitudinal axis X occurs at the center of the propeller 53, which is at the front of the front casing 112a, that is to say, at the intersection between the longitudinal axis X and the plane of the propeller 53.
[0039] With such an arrangement, the inner connecting rods 122 converge towards the axis of rotation X of the turbojet 102 to minimize stresses.
[0040] In the embodiment of the invention presented here, the two front connection points 121b of the outer connecting rods 120 are aligned along a transverse line D which is horizontal and therefore here parallel to the transverse axis Y.
[0041] The transverse line D is also here perpendicular to the median plane P and therefore parallel to the transverse axis Y.
[0042] In the embodiment of the invention presented here, each connection point 121a-b, 123a-b takes the form of a pivot joint, and for the external connecting rods 120, the axis The pivot joint is perpendicular to the median plane P, but a different orientation is possible.
[0043] To this end, each connection point 121a-b, 123a-b takes the form of a clevis-type connection, with a male clevis mounted movable in rotation in a female clevis via an axis.
[0044] For each front connection point 121b of an outer connecting rod 120, the female yoke is integral with the rear face 113 and the male yoke is formed by the front end 120b of the relevant connecting rod 120. For each front connection point 123b of an inner connecting rod 122, the female yoke is integral with the rear face 113 or the rear housing 112b, and the male yoke is formed by the front end 122b of the relevant connecting rod 122.
[0045] For each rear connection point 121a, 123a, the female clevis is integral with the lower longitudinal member 106a and the male clevis is formed by the rear end 120a, 122a of the relevant connecting rod 120, 122. Here, the female clevises of the rear connection points 123a of the inner connecting rods 122 are fixed to a beam 125 integral with the lower longitudinal member 106a and which here extends laterally from the primary structure 106. More generally, each second rear connection point 123a is fixed to the lower longitudinal member 106a via the beam 125.
[0046] To complete the attachment of the front casing 112a to the primary structure 106, the propulsion assembly 100 includes an engine attachment 150 which ensures an attachment between the front wall 106e of the primary structure 106 and the front casing 112a, and more particularly the upper part of the rear face 113.
[0047] Fig. 3 shows a particular embodiment of the motor attachment 150.
[0048] The motor mount 150 here comprises a female clevis 152a which is integral with the front wall 106e and a male clevis 152b (shown in shadow) which is integral with the rear face 113. The male clevis 152b is hinged within the female clevis 152a by an axis not shown. The axis of the clevis connection is perpendicular to the median plane P. The female clevis 152a is mounted at the level of the median plane P, that is to say, the two walls of the female clevis 152a are symmetrical to each other with respect to the median plane P.
[0049] The motor attachment 150 also includes here a pin 154a also called a "spigot" which is cylindrical and which has a first end fixed to the primary structure 106 and a second end which projects forward.
[0050] The axis of the pin 154a is in the median plane P and parallel to the longitudinal axis X.
[0051] The motor mount 150 also includes a housing 154b formed in the rear face 113, in which the pin 154a is housed. The shape of the housing 154b is such that the pin 154a can move within it parallel to the longitudinal axis X and the vertical axis Z, but it is blocked parallel to the transverse axis Y.
[0052] Such a particular arrangement makes it possible to obtain a hyperstatic system of degree 1 which ensures safety, for example, in the event of the failure of a connecting rod 120, 122. The clevis connection of the engine mount 150 takes up the forces in X and Z and the connection between the pin 154a and the housing 154b takes up the forces in Y. Each connecting rod 120, 122 also ensures the transfer of forces along its axis.
[0053] As specified above, in the embodiment of the invention shown in [Fig.3], the cleats 152a-b, the pin 154a and the housing 154b are arranged at the level of the median plane P.
[0054] In the particular embodiment presented here, the pin 154a is fixed to the lower spar 106a by attaching an extension of said pin 154a to said lower spar 106a. According to another embodiment not shown, the pin 154a may be fixed to the front wall 106e.
Claims
Demands
1. Propulsion assembly (100) of an aircraft (50), said propulsion assembly (100) having a longitudinal axis (X) and a vertical median plane (P) passing through the longitudinal axis (X) and comprising: - a turbojet engine (102) having a front casing (112a) with a rear face (113) perpendicular to the longitudinal axis (X) and a rear casing (112b), where the longitudinal axis (X) constitutes an axis of rotation of the turbojet engine (102), - a pylon (104) having a primary structure (106) with a lower spar (106a), - two outer connecting rods (120) disposed on either side of the median plane (P), where each outer connecting rod (120) has a rear end (120a) mounted articulated to the lower spar (106a) by a first rear connection point (121a) and a front end (120b) articulated mounting on the rear face (113) by a first front connection point (121b),and - two inner connecting rods (122) arranged on either side of the median plane (P) where each inner connecting rod (122) has a rear end (122a) mounted articulated to the lower side member (106a) by a second rear connection point (123a) and a front end (122b) mounted articulated to the rear face (113) or to the rear casing (112b) by a second front connection point (123b) and where the axes of the inner connecting rods (122) converge towards the longitudinal axis (X).
2. Propulsion assembly (200) according to claim 1, characterized in that it further comprises a propeller (53) at the front of the front casing (112a) and in that the convergence on the longitudinal axis (X) takes place at the center of the propeller (53).
3. Propulsive assembly (100) according to any one of claims 1 or 2, characterized in that the forward connection points (121b) of the outer connecting rods (120) are aligned along a horizontal transverse line (D).
4. Propulsive assembly (100) according to any one of claims 1 to 3, characterized in that each connection point (121a-b) of the outer connecting rods (120) takes the form of a pivot connection whose axis is perpendicular to the median plane (P).
5. Propulsion assembly (100) according to any one of claims 1 to 4, characterized in that it comprises a motor attachment (150) between a front wall (106e) of the primary structure (106) and the front casing (112a).
6. Propulsion assembly (100) according to claim 4, characterized in that the motor attachment (150) comprises a female clevis (152a) integral with the front wall (106e), a male clevis (152b) integral with the rear face (113) and mounted articulated in the female clevis (152a), a pin (154a) integral with the primary structure (106) and whose axis is parallel to the longitudinal axis (X) and a housing (154b) of the rear face (113) in which the pin (154a) is housed.
7. Propulsive assembly (100) according to claim 6, characterized in that the clevises (152a-b), the pin (154a) and the housing (154b) are arranged at the level of the median plane (P).
8. Propulsive assembly (100) according to any one of claims 6 or 7, characterized in that the pin (154a) is integral with the lower spar (106a).
9. Propulsion assembly (100) according to any one of claims 1 to 8, characterized in that each second rear connection point (123a) is fixed to the lower spar (106a) by means of a beam (125) integral with the lower spar (106a) and extending laterally from the primary structure (106).
10. Aircraft (50) comprising a wing (52) and a propulsion unit (100) according to any one of the preceding claims, the primary structure (106) of which is fixed under the wing (52).