Aircraft propulsion system comprising a turbojet engine, a mounting mast, and means for attaching the turbojet engine to the mounting mast
The described propulsion system achieves enhanced turbomachine performance through an isostatic connection between the turbojet engine and mounting mast using a rigid structure with upper and lower bars, arches, and connecting rods, addressing the limitations of existing systems.
Patent Information
- Authority / Receiving Office
- FR · FR
- Patent Type
- Applications
- Current Assignee / Owner
- AIRBUS OPERATIONS (SAS)
- Filing Date
- 2024-12-13
- Publication Date
- 2026-06-19
AI Technical Summary
Existing aircraft propulsion systems under the wing lack an isostatic connection between the turbojet engine and the mounting mast, limiting turbomachine performance optimization.
A propulsion system with a turbojet engine and mounting mast arrangement featuring a rigid structure, including upper and lower bars, arches, and connecting rods, providing an isostatic connection and blocking six degrees of freedom to enhance performance.
The isostatic connection allows for increased turbomachine performance by optimizing force paths and structural stability, creating a compact and efficient attachment system.
Smart Images
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Abstract
Description
Title of the invention: AIRCRAFT PROPULSION SYSTEM COMPRISING A TURBOJET ENGINE, A MOUNTING MAST AND MEANS FOR ATTACHING THE TURBOJET ENGINE TO THE MOUNTING MAST technical field
[0001] The present invention relates to the general field of mounting a turbojet engine under the wing of an aircraft. It specifically relates to a propulsion system comprising a turbojet engine, in particular a turbofan engine, a mounting mast, and means for attaching the turbojet engine under the mounting mast. It also applies to an aircraft equipped with such a propulsion system. PREVIOUS STATE OF THE ART
[0002] A prior art propulsion system is fixed under the wing of an aircraft. It comprises a turbojet engine and a mounting pylon by which the turbojet engine is fixed under the wing. The mounting pylon has a rigid structure, also called the primary structure, with fastening means for securing the turbojet engine.
[0003] These fastening means consist, among other things, of a front fastening of the turbojet, a rear fastening of the turbojet and a device for taking up the thrust forces generated by the turbojet.
[0004] The attachment mast also includes other fastening elements which ensure the attachment of the attachment mast to the wing.
[0005] Although such a structure is satisfactory, it is desirable to find an alternative arrangement which allows, among other things, for an isostatic connection between the turbojet and the mounting mast, while choosing the most suitable force paths allowing for increased turbomachine performance. Description of the invention
[0006] An object of the present invention is to propose a propulsion system comprising a turbojet engine, a mounting mast and means for fixing the turbojet engine under the mounting mast.
[0007] To this end, a propulsion system for an aircraft is proposed, said propulsion system comprising:
[0008] - a turbojet engine extending around a longitudinal axis and having a plane vertical median containing the longitudinal axis and comprising a front casing with a rear face perpendicular to the longitudinal axis and a rear casing,
[0009] - a rigging mast having a rigid structure with a front part and a lower longitudinal member to which a rear fitting is attached,
[0010] - a front engine mount which is fixed between an upper part of the front crankcase and the front part of the rigid structure,
[0011] - an arch with a base articulated to the rear fitting and two arms arranged on either side of the vertical median plane, each arm having a first end fixed to the base and a second end articulated to the rear casing,
[0012] - two upper bars arranged symmetrically on either side of the median plane vertical, where each is hinged to the rear face of the front casing by a first upper attachment point and hinged to the arch by a second upper attachment point, where the two upper bars are rigidly fixed to each other, and
[0013] - two lower bars arranged symmetrically on either side of the median plane vertical, where each is fixed in an articulated manner to the rear face of the front casing by a first lower connection point and to the arch by a second lower connection point.
[0014] Such an arrangement allows, among other things, for an isostatic connection between the turbojet and the mounting mast.
[0015] Advantageously, the rear fitting and the arch are inscribed in the same integration plane perpendicular to the vertical median plane.
[0016] According to a first particular embodiment, the two upper bars are fixed to each other by a plate fixed between them between the first upper connection points and the second upper connection points.
[0017] According to a second particular embodiment, the two upper bars cross at the level of the vertical median plane and are fixed to each other at the level of this crossing.
[0018] Advantageously, the upper bars are fixed horizontally and the lower bars are fixed at an angle between 45 and 70° with the rear face of the front housing, where the lower bars descend from the arch towards the rear face of the front housing.
[0019] Advantageously, the attachment between the base and the rear fitting is ensured, on the one hand, by two rear connecting rods arranged symmetrically on either side of the vertical median plane, where each rear connecting rod is fixed in an articulated manner by a first point of connection to the rear fitting and by a second point of connection to the base, and, on the other hand, at the level of the vertical median plane, by a third point of connection between the base and the rear fitting.
[0020] Advantageously, the rear connecting rods are included in the integration plane.
[0021] Advantageously, the attachment between the second end of each arm and the rear housing is ensured by two pairs of connecting rods arranged symmetrically in pairs on either side of the vertical median plane, and where each connecting rod is inscribed in a plane perpendicular to the longitudinal axis, and where each connecting rod is fixed in an articulated manner to the second end of the arm which is on the same side by a first point of connection and to the rear housing by a second point of connection.
[0022] Advantageously, the connecting rods are included in the integration plan.
[0023] Advantageously, for each pair of connecting rods, the two connecting rods are arranged symmetrically on either side of a horizontal plane passing through the longitudinal axis.
[0024] Advantageously, the front engine attachment comprises a front fitting fixed to the front part, two front connecting rods arranged symmetrically on either side of the vertical median plane and a vertical pin integral with the front fitting or the front housing and housed in a bore respectively of the front housing or the front fitting, where each front connecting rod is fixed in an articulated manner by a first point of connection to the front fitting and by a second point of connection to the front housing.
[0025] The invention relates to an aircraft comprising a propulsion system according to one of the preceding variants. Brief description of the drawings
[0026] 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:
[0027] [Fig-1] is a side view of an aircraft according to the invention,
[0028] [Fig.2] is a schematic perspective representation of a propulsion system according to a first embodiment of the invention,
[0029] [Fig.3] is a schematic perspective representation of a propulsion system according to a second embodiment of the invention,
[0030] [Fig.4] is a schematic side view representation of the propulsion system according to the first embodiment of the invention,
[0031] [Fig.5] is a cross-sectional view along line VV of [Fig.4], and
[0032] [Fig.6] is a cross-sectional view along line VLVI of [Fig.4].
[0033] DETAILED STATEMENT OF IMPROVEMENTS
[0034] Figure 1 shows an aircraft 50 having a fuselage 53 on each side of which a wing 52 is attached. Under each wing 52 is attached a propulsion system 100, 300 according to the invention, comprising a pylon 104 and a turbojet engine 102 housed here in a nacelle 200. The invention applies equally to a turbojet engine 102 of the unfaired fan type. The system of propulsion 100, 300 is fixed to wing 52 by the attachment mast 104 and the turbojet 102 is fixed under the attachment mast 104.
[0035] By convention, X is called the longitudinal axis of the turbojet 102, this axis X being parallel to a longitudinal direction of this turbojet 102 and to a longitudinal direction of the aircraft 50. On the other hand, Y is the transverse axis of the turbojet 102 which is horizontal when the aircraft 50 is on the ground and Z is the vertical axis or the vertical height when the aircraft 50 is on the ground, these three axes X, Y and Z being orthogonal to each other.
[0036] In addition, the terms "forward" and "rear" must be considered in relation to a direction of forward movement of the aircraft 50 during the operation of the turbojet 102, this direction being schematically represented by arrow F.
[0037] The turbojet 102 and the mounting mast 104 are globally symmetrical with respect to a vertical median plane P (XZ) which contains the longitudinal axis X and therefore the vertical direction Z. The transverse axis Y is perpendicular to the vertical median plane P.
[0038] Figs. 2 and 4 show the propulsion system 100 according to a first embodiment of the invention, [Fig. 3] shows the propulsion system 300 according to a second embodiment of the invention and Figs. 5 and 6 show details of the embodiment of the propulsion system 100, 300.
[0039] The propulsion system 100, 300 includes the turbojet 102 and the attachment mast 104 by which the turbojet 102 is fixed to the wing 52. The attachment mast 104 is represented here by its rigid structure 106, also called primary structure, which is fixed to the structure of the wing 52 by any suitable fastening means known to those skilled in the art.
[0040] The rigid structure 106 is in the form of a box which includes a front part 106a, located at the front of the rigid structure 106, a lower spar 106b extending below the rigid structure 106 and an upper spar 106e extending above the rigid structure 106. The rigid structure 106 also includes two side walls 106c-d on each side of the vertical median plane P. These various spars and walls are fixed to each other to form the rigid structure 106. The front part 106e includes, for example, a front wall and / or a part of the lower spar 106b and side walls 106c-d.
[0041] The turbojet 102 comprises, from front to rear, a front casing 103 and a rear casing 105, which is attached to the rear of the front casing 103 and in which elements of the turbojet 102 are housed, such as compression stages, a combustion chamber, turbine stages, and an exhaust cone. The front casing 103 is, for example, a fan casing in which a fan of the turbojet 102 is mounted; it can also be the casing located just behind the fan in the case of a turbojet with an unshod fan.
[0042] The front casing 103 has a diameter greater than the diameter of the rear casing 105.
[0043] The front casing 103 has a rear face 103a which is perpendicular to the longitudinal axis X and thus extends in a plane parallel to the YZ plane. The front crankcase 103 and the rear crankcase 105 form surfaces of revolution around the longitudinal axis X.
[0044] The propulsion system 100, 300 includes a front engine attachment 150 which ensures the attachment between an upper part of the front casing 103 and the front part 106a of the rigid structure 106.
[0045] The propulsion system 100, 300 also includes an arch 152 which is arranged around the rear casing 105 and at the rear of the rear surface 103a of the front casing 103.
[0046] A rear fitting 108 is rigidly fixed to the lower longitudinal member 106b under the rigid structure 106.
[0047] The arch 152 has a base 152a which is hinged to the rear fitting 108. The arch 152 also has two arms 152b-c arranged on either side of the vertical median plane P, i.e., symmetrically with respect to the vertical median plane P, there is an arm 152b on the port side and an arm 152c on the starboard side. Each arm 152b-c has a first end which is integral with the base 152a and a second end which is hinged to the rear housing 105. Each arm 152b-c may be an element fixed to the base 152a or form a single unit with the base 152a.
[0048] In the embodiment of the invention shown in the Figs., the second ends of each arm 152b-c of the arch 152 are respectively at 3 o'clock and 9 o'clock with respect to the longitudinal axis X. But the positions of the second ends of each arm 152b-c of the arch 152 can be arranged at + / - 45° with respect to these positions shown.
[0049] The propulsion system 100, 300 also includes bars 155, 355 and 157 which are arranged symmetrically on either side of the vertical median plane P.
[0050] There are thus two upper bars 155, 355 which are arranged in the upper part of the front housing 103 and each is fixed in an articulated manner to the rear face 103a of the front housing 103 by a first upper connection point 175a and in an articulated manner to the arch 152 by a second upper connection point 175b.
[0051] The two upper bars 155, 355 are rigidly fixed to each other, that is to say they are fixed directly to each other and the two embodiments show two particular arrangements of this joining.
[0052] There are also two lower bars 157 which are arranged below the upper bars 155 and each is hinged to the rear face 103a of the front casing 103 by a first lower connection point 177a and to the arch 152 by a second lower connection point 177b.
[0053] Viewed from above, the upper bars 155 are inside relative to the lower bars 157.
[0054] Each connection point 175a-b, 177a-b of each bar 155, 355, 157 takes the form of a ball joint to limit bending moments. The first connection points 175a and 177a are not visible in [Fig. 3] but they take the same form as those in [Fig. 2].
[0055] Such a propulsion system 100, 300 thus allows for an isostatic connection between the turbojet and the attachment mast due to the blocking of 6 degrees of freedom by combination of the ball joint and rigid connections between the upper bars 155, 355.
[0056] The rear fitting 108 and the arch 152 are inscribed in the same integration plane P' which is perpendicular to the longitudinal axis X.
[0057] The placement of bars 155, 355 and 157 makes it possible to create a compact structure.
[0058] In the embodiment of the invention shown in Figs. 2 to 4, the bars The upper bars 155 and 355 are fixed horizontally, and the lower bars 157 are fixed at an angle between 45° and 70° to the rear face 103a of the front housing 103. The lower bars 157 descend from the arch 152 towards the rear face 103a of the front housing 103. The first lower connection point 177a is generally at 3 o'clock (or 9 o'clock) on the rear face 103a relative to the longitudinal axis X. However, the positions of the first lower connection points 177a of each lower bar 157 can be arranged at + / - 45° relative to the positions shown.
[0059] For the upper bars 155, 355, the upper connection points 175a-b have a principal axis of rotation which is perpendicular to the vertical median plane P and for the lower bars 157, the lower connection points 177a-b have a principal axis of rotation which is perpendicular to the axis of the lower bar 157 considered and parallel to the vertical median plane P.
[0060] Each connection point 175a-b, 177a-b here takes the form of a connection by cleat.
[0061] In the first embodiment of the invention, the two upper bars 155 are fixed to each other by the placement of a rigid plate 180 and fixed, for example by welding, between the two upper bars 155. The plate 180 extends globally horizontally and is between the first upper connection points 175a and the second upper connection points 175b.
[0062] In the second embodiment of the invention, the two upper bars 355 intersect at the vertical median plane P and are fixed to each other at this intersection. The two upper bars 355 thus form an X whose Four branches are fixed in an articulated manner. The two upper bars 355 are joined to each other approximately at the midpoint of their lengths.
[0063] Fig. 6 shows more clearly an example of the attachment between the base 152a of the arch 152 and the rear fitting 108. This attachment is ensured by two rear connecting rods 170a-b and by a third connection point 171c which is a standby connection point, that is to say that it only becomes active in the event of a failure of one of the rear connecting rods 170a-b.
[0064] The two rear connecting rods 170a-b are arranged symmetrically on either side of the vertical median plane P and each rear connecting rod 170a-b is fixed in an articulated manner by a first connection point 171a to the rear fitting 108 and by a second connection point 171b to the base 152a. Each connection point 171a-b linked to the rear connecting rods 170a-b takes at least the form of a rotation, but preferably it takes the form of a ball joint to limit bending moments and each one has a principal axis of rotation which is parallel to the longitudinal axis X.
[0065] In the embodiment of the invention shown here, the rear connecting rods 170a-b are inscribed in the integration plane P'.
[0066] The third connection point 171c provides a connection between the base 152a and the rear fitting 108 and is located at the level of the vertical median plane P. This third connection point 171c takes at least the form of a rotation, but preferably it takes the form of a ball joint to limit bending moments and it has here a main axis of rotation which is parallel to the longitudinal axis X.
[0067] Each connection point 171a-c here takes the form of a connection by cleat.
[0068] In the case of the third connection point 171c, the shaft of the clevis connection is diameter slightly smaller than the diameter of the bores into which it is fitted so as to only come into contact with said bores when necessary.
[0069] Fig. 6 also shows a particular embodiment of the attachment between the second end of each arm 152b-c and the rear housing 105. This attachment is ensured by two pairs of connecting rods 158a-b, where the pairs are arranged symmetrically on either side of the vertical median plane P and where each connecting rod 158a-b is inscribed in a plane perpendicular to the longitudinal axis X which is also the plane in which the arch 152 is inscribed.
[0070] Each connecting rod 158a-b is fixed in an articulated and removable manner to the second end of the arm 152a-b which is on the same side by a first connection point 159a and to the rear housing 105 by a second connection point 159b.
[0071] Here, for each pair of connecting rods 158a-b, the two connecting rods 158a-b are arranged symmetrically on either side of a horizontal plane passing through the longitudinal axis X, i.e., the XY plane. This symmetrical arrangement ensures the positioning of the rear housing 105 relative to the arch 152.
[0072] Each connection point 159a-b linked to the connecting rods 158a-b takes at least the form of a rotation, but preferably it takes the form of a ball joint to limit the bending moments and each of these connection points 159a-b has here a principal axis of rotation which is perpendicular to the axis of the connecting rod 158a-b considered and inscribed in a plane perpendicular to the longitudinal axis X and which is also the plane in which the arch 152 is inscribed.
[0073] Each connection point 159a-b here takes the form of a connection by cleat.
[0074] In the embodiment of the invention shown here, the connecting rods 158a-b are included in the integration plan P'.
[0075] Fig. 5 shows more clearly an example of a front engine mount 150 implemented in the invention, but the engine mount 150 may have a different architecture.
[0076] The front engine mount 150 comprises a front bracket 160 which is fixed to the front part 106a and two front connecting rods 162a-b arranged symmetrically on either side of the vertical median plane P. Each front connecting rod 162a-b is hinged by a first connection point 164a to the front bracket 160 and by a second connection point 164b to the front housing 103. Each connection point 164a-b linked to the front connecting rods 162a-b takes at least the form of a rotation, but preferably it takes the form of a ball joint to limit bending moments and each has a principal axis of rotation which is parallel to the longitudinal axis X. Each connection point 164a-b takes the form of a clevis joint.
[0077] The front motor attachment 150 also includes a "spigot" type connection with a pin 166 which extends vertically, i.e. parallel to the vertical axis Z and is inscribed in the vertical median plane P.
[0078] The pin 166 is integral with the front fitting 160 or the front housing 103 and is housed as appropriate in a bore 168 of the front housing 103 or the front fitting 160.
[0079] The fit between the bore 168 and the pin 166 is such that there is no displacement along the longitudinal axis X or along the transverse axis Y and only displacements along the vertical axis Z.
Claims
Demands
1. Propulsion system (100, 300) for an aircraft (50), said propulsion system (100, 300) comprising: - a turbojet engine (102) extending about a longitudinal axis (X) and having a vertical median plane (P) containing the longitudinal axis (X) and comprising a front casing (103) with a rear face (103a) perpendicular to the longitudinal axis (X) and a rear casing (105), - a mounting mast (104) having a rigid structure (106) with a front portion (106a) and a lower spar (106b) to which a rear fitting (108) is attached, - a front engine mount (150) which is fixed between an upper portion of the front casing (103) and the front portion (106a) of the rigid structure (106), - an arch (152) with a base (152a) fixed in an articulated manner to the rear fitting (108) and two arms (152b-c) arranged on either side of the vertical median plane (P),each arm (152b-c) having a first end fixed to the base (152a) and a second end hinged to the rear housing (105), - two upper bars (155, 355) arranged symmetrically on either side of the vertical median plane (P), where each is hinged to the rear face (103a) of the front housing (103) by a first upper connection point (175a) and hinged to the arch (152) by a second upper connection point (175b), where the two upper bars (155, 355) are rigidly fixed to each other, and - two lower bars (157) arranged symmetrically on either side of the vertical median plane (P), where each is hinged to the rear face (103a) of the front housing (103) by a first lower connection point (177a) and to the arch (152) by a second lower connection point (177b).
2. Propulsion system (100, 300) according to claim 1, characterized in that the rear fitting (108) and the arch (152) are inscribed in the same integration plane (P') perpendicular to the longitudinal axis (X).
3. Propulsion system (100) according to claim 1 or 2, characterized in that the two upper bars (155) are fixed to each other by a plate (180) fixed between them between the first upper connection points (175a) and second upper connection points (175b).
4. Propulsion system (300) according to any one of claims 1 or 2, characterized in that the two upper bars (355) cross at the level of the vertical median plane (P) and are fixed to each other at the level of this crossing.
5. Propulsion system (100, 300) according to any one of claims 1 to 4, characterized in that the upper bars (155, 355) are fixed horizontally and the lower bars (157) are fixed at an angle between 45 and 70° with the rear face (103a) of the front housing (103), where the lower bars (157) descend from the arch (152) towards the rear face (103a) of the front housing (103).
6. Propulsion system (100, 300) according to any one of claims 1 to 5, characterized in that the attachment between the base (152a) and the rear fitting (108) is ensured, on the one hand, by two rear connecting rods (170a-b) arranged symmetrically on either side of the vertical median plane (P), where each rear connecting rod (170a-b) is fixed in an articulated manner by a first connection point (171a) to the rear fitting (108) and by a second connection point (171b) to the base (152a), and, on the other hand, at the level of the vertical median plane (P), by a third connection point (171c) between the base (152a) and the rear fitting (108).
7. Propulsion system (100, 300) according to claim 6 when it depends on claim 2, characterized in that the rear connecting rods (170a-b) are inscribed in the integration plane (P').
8. Propulsion system (100, 300) according to any one of claims 1 to 7, characterized in that the attachment between the second end of each arm (152b-c) and the rear casing (105) is ensured by two pairs of connecting rods (158a-b) arranged symmetrically in pairs, on either side of the vertical median plane (P), and where each connecting rod (158a-b) is inscribed in a plane perpendicular to the longitudinal axis (X), and where each connecting rod (158a-b) is fixed in an articulated manner to the second end of the arm (152a-b) which is on the same side by a first connection point (159a) and to the rear casing (105) by a second connection point (159b).
9. Propulsion system (100, 300) according to claim 8 when it depends on claim 2, characterized in that the connecting rods (158a-b) are inscribed in the integration plane (P').
10. Propulsion system (100, 300) according to any one of claims 8 or 9, characterized in that for each pair of connecting rods (158a-b), the two connecting rods (158a-b) are arranged symmetrically on either side of a horizontal plane passing through the longitudinal axis (X).
11. Propulsion system (100, 300) according to any one of claims 1 to 10, characterized in that the front engine attachment (150) comprises a front fitting (160) fixed to the front part (106a), two front connecting rods (162a-b) arranged symmetrically on either side of the vertical median plane (P) and a vertical pin (166) integral with the front fitting (160) or the front housing (103) and housed in a bore (168) respectively of the front housing (103) or the front fitting (160), where each front connecting rod (162a-b) is fixed in an articulated manner by a first connection point (164a) to the front fitting (160) and by a second connection point (164b) to the front housing (103).
12. Aircraft (50) comprising a propulsion system (100, 300) according to any one of the preceding claims.