Assembly for an aircraft comprising a turbomachine, a cradle and an attachment system
Patent Information
- Authority / Receiving Office
- WO · WO
- Patent Type
- Applications
- Current Assignee / Owner
- SAFRAN AIRCRAFT ENGINES SAS
- Filing Date
- 2026-01-21
- Publication Date
- 2026-07-30
Smart Images
Figure FR2026050057_30072026_PF_FP_ABST
Abstract
Description
DESCRIPTION TITLE: Aircraft assembly comprising a turbomachine, a cradle and a mounting system TECHNICAL FIELD OF THE INVENTION
[0001] The invention relates to the field of turbomachine attachments to an aircraft. In particular, the invention relates to an aircraft assembly comprising a turbomachine, a cradle, and a system for attaching the turbomachine to the cradle. STATE OF PRIOR ART
[0002] Existing systems for attaching a turbomachine to a pylon or aircraft cradle are described, for example, in documents CA2958686, WO2022 / 245363, WO2022 / 248791 or WO2023 / 198962.
[0003] A turbomachine typically comprises, in one flow direction, an inlet section, a compressor section, a combustion section, a turbine section, and an exhaust section. During operation, air enters through the inlet section and flows to the compressor section, where one or more axial compressors progressively compress the air until it reaches the combustion section, where combustion gases are generated. These combustion gases then flow from the combustion section along a defined hot gas path in the turbine section and exit the combustion section through the exhaust section. Such a turbomachine produces thrust capable of propelling a motor vehicle, such as an aircraft.On an aircraft, the thrust generated by the turbomachine produces thrust forces transmitted to a support, such as a pylon or cradle, and similarly, the aircraft applies equal and opposite reaction forces to the support. This load induces a pitching moment or a yaw moment in the turbomachine. It is therefore necessary to reduce these pitching and yaw moments applied to the turbomachine so that it does not deform to the point of degrading its operating performance.
[0004] Indeed, when a turbomachine generates thrust and is subjected to maneuvering loads (aerodynamic forces on a nacelle or propeller associated with the turbomachine), the turbomachine itself is subjected to stresses. The backbone bending of the turbomachine casing, induced by these stresses, creates gaps and even wear, degrading the turbomachine's performance, thus increasing fuel consumption and accelerating its aging.
[0005] In the case of unfaired turbomachinery typically used on short- or medium-range aircraft, the turbomachine's mounting is critical because the turbomachine's large-diameter propeller induces significant loads. Furthermore, to achieve high performance, the turbomachine has a small, high-pressure body, making it susceptible to various stresses such as gravitational loads, aircraft maneuvers, and aerodynamic loads.
[0006] A conventional turbomachine suspension with an upstream attachment on an upstream casing and a downstream attachment on a turbine casing or exhaust casing does not allow for optimization of the performance of the turbomachine assembly and aircraft cradle or pylon.
[0007] Another known solution, from document WO2022 / 245363, is to position a downstream suspension on the casing upstream of a high-pressure body (cantilevered high-pressure body solution). The bending moments induced by aerodynamic forces upstream of the turbomachine and the thrust will no longer be transmitted through the high-pressure body. Furthermore, this solution can create significant displacements between the tower and the turbomachine at the high-pressure body not supported by suspensions, particularly when the turbomachine is subjected to acceleration factors under gravitational acceleration and aircraft maneuvers, resulting in significant clearance loss and displacement between the turbomachine and the tower. Moreover, since the two suspension planes are close together, it is difficult to achieve a good compromise in stiffness between the tower and the upstream casing, which also leads to significant clearance loss between the turbomachine and the tower under load. DESCRIPTION OF THE INVENTION
[0008] One aim of the invention is to provide an aircraft assembly comprising a turbomachine, a cradle and a system for attaching the turbomachine to the cradle which allows for a compromise in attachment that limits the consumption of play in the high-pressure body.
[0009] To this end, the invention provides an assembly for an aircraft comprising a turbomachine, a cradle including an upstream frame and a system for attaching the turbomachine to the cradle, the turbomachine extending along a longitudinal axis oriented in a direction of a flow generated by the turbomachine, the turbomachine comprising, along the longitudinal axis, a propeller extending in a plane P orthogonal to the longitudinal axis, an upstream casing, an intermediate casing, a turbine casing and an exhaust casing, the attachment system comprising upstream attachment means for attaching the turbomachine to the upstream frame of the cradle fixed at the level of the upstream casing of the turbomachine, intermediate attachment means for attaching the turbomachine to the cradle fixed at the level of the intermediate casing of the turbomachine and rear attachment means for attaching the turbomachine to the cradle fixed at the level of one of the turbine and exhaust casings of the turbomachine,wherein the upstream fastening means comprise a series of three coupling means for the upstream housing to the upstream cradle frame extending towards the propeller from the upstream frame and arranged such that each resultant force of the coupling means has a direction intersecting the longitudinal axis at the level of the plane P of the propeller, wherein the intermediate fastening means comprise flexible attachment means and wherein the rear fastening means comprise rigid fastening means.
[0010] Advantageously, but optionally, the assembly according to the invention has at least one of the following technical characteristics: - each coupling means comprises a ball-joint connecting rod extending along the direction of the resultant of the associated recovery force; - the coupling means are equally distributed over a circumference of the upstream casing; - the intermediate fixing means are fixed to the upstream frame of the cradle; - the flexible attachment means comprise supports including flexible pads or springs or ball-joint connecting rods mounted in series with flexible pads; and, - the rear fixing means include a "yoke" type fixing comprising a ball joint and a boomerang link. BRIEF DESCRIPTION OF THE FIGURES
[0011] Other features and advantages of the invention will become apparent from the following description of an embodiment of the invention. See the attached drawings:
[0012] [Fig. 1] is a schematic three-dimensional view of an embodiment of an aircraft assembly comprising a turbomachine, a cradle, and a system for connecting the turbomachine to the cradle according to the invention; and,
[0013] [Fig.2] are schematic views according to plans of the upstream, intermediate and turbine / exhaust casings of the whole of figure 1.
[0014] For clarity, identical or similar elements are identified by identical reference symbols across all figures. DETAILED DESCRIPTION OF A METHOD OF IMPLEMENTATION
[0015] With reference to Figure 1 and Figure 2, we will describe an embodiment of an assembly according to the invention.
[0016] This embodiment of an assembly according to the invention comprises a turbomachine 1, a cradle 2, and a fastening system 240, 25, 270, 271 for attaching the turbomachine 1 to the cradle 2. As is known per se, the cradle 2 is generally itself attached to an aircraft wing. The turbomachine 1 comprises, in the direction of a flow, a propeller 3, rotating in a plane P, an upstream casing 4, an intermediate casing 5, a turbine casing 6, and an exhaust casing 7. The turbomachine 1 extends along a longitudinal axis XX, the plane P being perpendicular to the longitudinal axis XX. It should be noted that generally the turbine casing 6 (also called "Turbine Vane Frame" according to Anglo-Saxon terminology) is equipped with arms forming stator blades, and the exhaust casing 7 (also called "Turbine Rear Frame" according to Anglo-Saxon terminology) is the last casing of the turbomachine 1.
[0017] The cradle 2 extends parallel to the longitudinal axis XX and is generally located above the turbomachine 1. Here, it includes an upstream frame 21 in the shape of an arch, partially surrounding the turbomachine 1, generally at the level of the intermediate casing 5.
[0018] The fixing system 240, 25, 270, 271 here includes upstream fixing means 240 of the turbomachine 1 to the upstream frame 21 of the cradle 2 fixed at the upstream casing 4 of the turbomachine 1, intermediate fixing means 25 of the turbomachine 1 to the cradle 2 fixed at the intermediate casing 5 of the turbomachine 1 and rear fixing means 270, 271 of the turbomachine 1 to the cradle 2 fixed at one of the turbine casings 6 and exhaust casings 7 of the turbomachine 1.
[0019] The upstream fastening means here comprise a series of three coupling means 240 connecting the upstream housing 4 to the upstream frame 21 of the cradle 2, extending towards the propeller 3 from the upstream frame 21 and arranged such that each resultant force exerted by the coupling means 240 has a direction D intersecting the longitudinal axis XX at the plane P of the propeller 3. Each coupling means 240 is a ball-and-socket joint extending, along the convergent direction D of the associated resultant force exerted by the coupling means, between the upstream housing 4 and the upstream frame 21 of the cradle 2. The series of three coupling means 240 is equally distributed around a circumference or periphery of the upstream housing 4. This allows for optimal absorption of the aerodynamic forces without their transmission to the high-pressure body of the turbomachine 1.
[0020] The intermediate fastening means include flexible attachment means 25, here three in number. The flexible attachment means 25 comprise supports with flexible pads. Alternatively, the flexible attachment means 25 include springs or ball-and-socket connecting rods with flexible pads mounted in series. The flexible attachment means 25 limit the banana-like deflection of the middle of the turbomachine 1 under inertial loads. Here, the intermediate fastening means 25 are attached to the upstream frame 21 of the cradle 2. Alternatively, the flexible attachment means 25 are attached to the cradle 2 at the same attachment points to said cradle 2 as the ball-and-socket connecting rods 240 of the coupling means of the upstream fastening means. Alternatively still, the intermediate fastening means 25 are evenly distributed around a circumference or periphery of the intermediate housing 5.
[0021] In the preceding and subsequent descriptions, "flexible" means an element that allows at least one degree of freedom within a predetermined range, with or without reduced force transmission compared to a rigid connecting element between the two parts it joins. Similarly, a flexible fastener or attachment means a fastener or attachment that allows at least one degree of freedom within a predetermined range with reduced force transmission compared to a rigid fastener or attachment, thus providing localized relief.
[0022] The rear mounting means here include rigid mounting means 270, 271. The rigid mounting means comprise a "yoke" type mounting 270, 271 including a ball-joint connecting rod 270 and a boomerang link 271. The boomerang link 271 includes a boomerang-shaped part fixed by three kinematic links: a ball joint with the turbine housing 6 or exhaust housing 7 of the turbomachine 1 and two ball joints with the cradle 2. The "yoke" type mounting allows for the absorption of vertical and lateral forces as well as engine torque and for securely holding the high-pressure body under operating loads.
[0023] In the context of the invention, a rigid element or fixing is defined as an element or fixing which allows forces to be transmitted in at least one direction, in particular vertical and / or lateral and / or torque forces in order to ensure their absorption.
[0024] The implementation of one of the previously described embodiments of an assembly according to the invention has the advantage of being the least hyperstatic compared to traditional assemblies and of allowing effective protection of the high-pressure body from axial moment forces while avoiding cantilevering it and minimizing the mass of the attachment of the turbomachine 1 while avoiding cantilevering.
[0025] This allows control of the high-pressure body clearances to ensure its performance / operability in a new engine and a removal time compatible with short and medium-haul operation of the aircraft thus equipped.
[0026] Naturally, the invention described above is by way of example. It is understood that a person skilled in the art is capable of carrying out different embodiments of the invention without departing from its scope.
[0027] It is emphasized that all features, as they are apparent to a person skilled in the art from the present description, drawings and attached claims, even if in practice they have only been described in relation to other specific features, both individually and in any combinations, may be combined with other features or groups of features disclosed herein, provided that this has not been expressly excluded or that technical circumstances render such combinations impossible or meaningless.
Claims
DEMANDS 1. Assembly for an aircraft comprising a turbomachine (1), a cradle (2) including an upstream frame (21) and a fastening system (240, 25, 270, 271) of the turbomachine (1) to the cradle (2), the turbomachine extending along a longitudinal axis (XX) oriented in a direction of a flow generated by the turbomachine, the turbomachine comprising, along the longitudinal axis (XX), a propeller (3) extending in a plane P orthogonal to the longitudinal axis (XX), an upstream casing (4), an intermediate casing (5), a turbine casing (6) and an exhaust casing (7), the fastening system including upstream fastening means of the turbomachine to the upstream frame of the cradle fixed at the level of the upstream casing (4) of the turbomachine,intermediate fixing means of the turbomachine to the cradle fixed at the level of the intermediate casing (5) of the turbomachine and rear fixing means of the turbomachine to the cradle fixed at the level of one of the turbine casings (6) and exhaust casings (7) of the turbomachine, wherein the upstream fixing means comprise a series of three coupling means (240) of the upstream casing to the upstream frame of the cradle extending towards the propeller from the upstream frame and arranged such that each resultant of the recovery force of the coupling means has a direction (D) intersecting the longitudinal axis (XX) at the level of the plane P of the propeller, wherein the intermediate fixing means comprise flexible attachment means (25) and wherein the rear fixing means comprise rigid fixing means (270,271).
2. Assembly according to claim 1, in which each coupling means comprises a ball-and-socket connecting rod extending along the direction (D) of the resultant associated recovery force.
3. Assembly according to any one of claims 1 to 2, wherein the coupling means are equidistributed over a circumference of the upstream casing.
4. Assembly according to any one of claims 1 to 3, wherein the intermediate fixing means are fixed to the upstream frame of the cradle.
5. Assembly according to any one of claims 1 to 4, wherein the flexible attachment means comprise supports including flexible pads or springs or ball-to-ball joints mounted in series with flexible pads.
6. Assembly according to any one of claims 1 to 5, wherein the rear fastening means comprise a "yoke" type fastening comprising a ball-to-ball joint (270) and a boomerang link (271).