NACELLE FOR AN AIRCRAFT ENGINE

Abstract

AIRCRAFT ENGINE NACELLE The invention relates to a nacelle (100) for an aircraft propulsion system wherein the nacelle (100) comprises at least one cowling (102) mounted hinged between a closed position and an open position about a hinge axis (103) and, for each cowling (102), at least one engine assembly (104) comprising an actuating shaft (106) rotatable about the hinge axis (103). The actuating shaft (106) is configured to move the associated cowling (102) between the closed and open positions. With such an arrangement, the engine assembly is integrated into the hinge so as to ensure optimal compactness and provide unobstructed access to the core located in the nacelle. Fig. 4

Description

Title of the invention: NACELLE FOR AN AIRCRAFT ENGINE technical field

[0001] The present invention relates to a nacelle for an aircraft propulsion system comprising at least one movable cowling and an engine assembly arranged to move said at least one movable cowling, an aircraft propulsion system comprising such a nacelle and an aircraft comprising at least such a propulsion system. PREVIOUS STATE OF THE ART

[0002] Fig. 1 shows a prior art propulsion system 500. This propulsion system 500 is fitted to an aircraft and conventionally comprises a core 502 surrounded by a nacelle 504 which forms, among other things, an aerodynamic surface around the core 502 and the propulsion system is generally fixed under a wing of the aircraft by a mounting mast 503.

[0003] The nacelle 504 includes hoods 506 which are hinged mounted on the towing mast 503 by means of hinges 508 and which are locked in the closed position by a locking system which locks the hoods 506 to each other at the level of a lower spar 510 integrated into each hood 506.

[0004] For maintenance reasons, it is necessary to be able to open the hoods 506 by rotating them around the axes of the hinges 508. To open a hood 506, the technician unlocks the locking system and lifts the hood 506, the reverse maneuver allowing the hood 506 to be closed.

[0005] A cylinder 512a-b is put in place to assist in opening a hood 506.

[0006] In certain arrangements (on the left in [Fig.1]), the cylinder 512a is mounted between the hood 506 and a core structure 502.

[0007] In other arrangements (on the right in [Fig.1]), the jack 512b is mounted between the hood 506 and a structure of the attachment mast 503.

[0008] The use of jacks can limit the opening angle of the hoods and it is desirable to find an arrangement which allows for a greater opening of the hoods.

[0009] In addition, with prior art arrangements, the cylinders 512b are potentially subjected to high temperatures and the change of the core may be hindered by the presence of the cylinders 512a.

[0010] It is therefore desirable to find an arrangement that provides improvements. Description of the invention

[0011] An object of the present invention is to provide a nacelle for an aircraft propulsion system which includes at least one movable cowling and an engine assembly arranged to move said at least one movable cowling.

[0012] To this end, a nacelle is proposed for an aircraft propulsion system, said nacelle extending around a longitudinal axis and comprising:

[0013] - at least one hinged hood mounted between a closed position and an open position around a hinge axis extending parallel to the longitudinal axis X,

[0014] - for each hood, at least one motor assembly comprising a shaft of movable actuation rotating about said hinge axis and where said actuation shaft is configured to move said associated hood between said closed position and said open position.

[0015] In this way, the motor assembly is integrated into the hinge so as to guarantee optimal space and provide unobstructed access to the core located in the nacelle.

[0016] Advantageously, said motor assembly comprises a motor with a motor shaft globally parallel to said hinge axis and a gear system having an input pinion fixed to the motor shaft and an output pinion fixed to the drive shaft, where the gear ratio of the gear system is greater than 1.

[0017] According to a particular aspect of the invention, said motor is an electric motor.

[0018] According to another particular aspect of the invention, said motor is a hydraulic motor.

[0019] According to yet another particular aspect of the invention, said engine assembly includes locking means configured to lock and unlock the position of said hood.

[0020] According to a particular aspect of the invention, said motor is intended to be fixed to a mounting mast of said aircraft and said drive shaft is fixed to the cowling.

[0021] According to one variant, said motor is fixed to the cowling and said drive shaft is intended to be fixed to a mounting mast of said aircraft.

[0022] According to a particular aspect of this variant, said hood comprises an inner wall and an outer wall which together define a housing and said engine is fixed in said housing.

[0023] According to a particular aspect of the invention, each hood comprises two motor assemblies spaced apart from each other along said hinge axis.

[0024] The invention also relates to a propulsion system for an aircraft comprising a core and a nacelle as described above which surrounds the core.

[0025] The invention also relates to an aircraft comprising at least one such propulsion system. 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 schematic front view representation of a prior art gondola,

[0028] [Fig.2] is a side view of an aircraft comprising a nacelle according to the invention,

[0029] [Fig.3] is a schematic front view representation of a gondola according to the invention in the closed position for each hood,

[0030] [Fig.4] is a schematic front view representation of the nacelle of [Fig.3] in the closed position for one of the hoods and in the partially open position for the other hood, and

[0031] [Fig.5] is a partial schematic top view representation of a gondola of the [Fig.3].

[0032] DETAILED STATEMENT OF IMPROVEMENTS

[0033] In the following description, terms relating to a position are taken with reference to an aircraft in a forward position as shown in [Fig.2], and where arrow F shows the direction of forward movement of the aircraft in flight.

[0034] Fig. 2 shows an aircraft 10 comprising a fuselage 12 on either side of which a wing 14 is attached. Each wing 14 supports at least one propulsion system 50 by means of a mounting mast 16 fixed between a structure of the wing 14 and a structure of the mounting mast 16.

[0035] The motorization system 50 comprises a core 60 (in dotted lines on the [Fig.2]) surrounded by a nacelle 100 according to the invention.

[0036] In the following description, and by convention, X is called the longitudinal axis of the nacelle 100 which is parallel to the longitudinal axis of the aircraft 10 or roll axis, oriented positively in the direction of advancement of the aircraft 10, Y is called the transverse axis which is parallel to the pitch axis of the aircraft 10 which is horizontal when the aircraft 10 is on the ground, and Z is called the vertical axis which is parallel to the yaw axis when the aircraft 10 is on the ground, these three directions X, Y and Z being orthogonal to each other.

[0037] The nacelle 100 has a vertical median plane P of symmetry which coincides with the vertical plane XZ and, in the embodiment of the invention presented in [Fig.3], the nacelle 100 has on either side of the vertical median plane P, a hood 102.

[0038] Each hood 102 here takes the form of a half-cylinder so as to form together a cylinder surrounding the core 60.

[0039] The core 60, for example, takes the form of a turbofan engine with a fan at the front. The cowling 102 can then serve as the fan cowling or the cowling for the thrust reverser system.

[0040] Each hood 102 is hinged on a structure which may be a structure of the attachment mast 16. The articulation of each hood 102 is made around a hinge axis 103 and each hood 102 is movable between a closed position in which the hood 102 is tightened around the core 60 and an open position in which the hood 102 is moved away from the core 60. In [Fig.4], the port hood 102 is in the open position and the starboard hood 102 is in the closed position.

[0041] In the closed position, the two hoods 102 come together against each other, at the level of a lower spar 62 of each hood 102. Each hood 102 thus comes into contact with the lower spar 62 of the other hood 102, at the level of its own lower spar 62, which is, in the closed position, arranged at the level of the lower part of the nacelle 100, at 6 o'clock.

[0042] The hinge axes 103 are arranged in the upper part of each hood 102 and the hoods 102 are mounted hinged on the mounting mast 16 around the associated hinge axis 103.

[0043] To lock each hood 102 in the closed position, the platform 100 may include locking systems (not shown) accessible from outside the platform 100 by a technician. Each locking system can take any form known to those skilled in the art and alternately assumes a locked position in which it locks the associated hood 102 in the closed position, or an unlocked position in which it does not lock the associated hood 102, which is then free to move from the closed position to the open position and vice versa. For redundancy, each hood 102 is equipped with at least two separate locking systems.

[0044] Generally, the platform 100 comprises at least one hood 102 and at least one motor assembly 104 for each hood 102. In the embodiment of the invention shown in Figs. 3 and 4, only one motor assembly 104 for each hood 102 is visible. Although the invention could allow the hood 102 to be rotated using only one motor assembly 104 per hood 102, it is intended that there will be two or more motor assemblies 104 (as illustrated in [Fig. 5]) per hood 102 in order to distribute the torque required to move each hood 2 across the different motor assemblies 104 and to improve operator safety by introducing independent force paths.

[0045] Each motor assembly 104 has a drive shaft 106 that is movable and rotates about an axis of rotation X' which extends globally coaxially to the hinge axis 103 of the hood 102, that is, within manufacturing tolerances. In other words, the drive shaft 106 is mobile in rotation around the hinge axis 103.

[0046] Each motor assembly 104 is arranged to rotate each drive shaft 106 alternately in an opening direction to move the associated hood 102 from the closed position to the open position and in a closing direction to move the associated hood 102 from the open position to the closed position. The opening direction is the opposite of the closing direction.

[0047] With this arrangement, the motor assembly 104 is integrated into the hinge between the hood and the lifting mast 16 to ensure optimal space requirements. Furthermore, this arrangement provides unobstructed access to the core located in the platform. Indeed, it is no longer necessary to implement a jack system between the lifting mast and the hood, or between the core and the hood. Access to the core is thus freed up, and maintenance operations are facilitated since operators have a larger working space, particularly when the core needs to be changed and therefore removed from the platform.

[0048] To operate each motor assembly 104, a control unit (not shown) is provided to control the rotation in one direction or the other and to stop rotation as needed. The control unit takes, for example, the form of a processor which may be supplemented by RAM (Random Access Memory), ROM (Read Only Memory) or Flash memory, a storage unit or a storage media reader (STCK), such as an SD card reader (Secure Digital) or an HDD (Hard Disk Drive), and a communication interface to communicate with the motor assembly 104.

[0049] With such an arrangement, it is therefore sufficient to control the motor assembly 104 to rotate the actuating shaft(s) 106 to open or close each hood 102 associated with a simple system and having a large opening angle.

[0050] Furthermore, the motor assemblies 104 are arranged in the upper part of the nacelle 100, that is, generally at 12 o'clock and in the vicinity of the lifting mast 16, that is, at a distance from any potential thermal radiation from the core 60. As illustrated in [Fig. 5], each motor assembly 104 can be fixed directly to the lifting mast 16, or to a structure 161 itself fixed to the lifting mast 16. More specifically, the motor 104, as well as the gearbox 104b and the locking means 104c when deployed (and which are described later in this description), are fixed to the lifting mast 16. The drive shaft 106, on the other hand, is fixed to the cowling 102. In this case, the motor 104 and the gearbox 104b and the locking means 104c, when engaged, remain fixed relative to the attachment mast 16 and the actuating shaft 106 pivots with the hood 102 around the hinge axis 103 (which is globally identical to the rotation axis X') when opening / closing the hood 102.

[0051] In one variant (not illustrated), each motor assembly 104 can be integrated into the thickness of a wall of the hood 102, near the attachment mast 16. More specifically, the hood 102 has an inner wall and an outer wall which together define a housing in which the motor 104a as well as the gearbox 104b and the locking means 104c are fixed when they are implemented. The drive shaft 106 is fixed to the mounting mast 16. In this case, when the drive shaft 106 pivots, the hood 102 and the motor 104a, as well as the gearbox 104b and the locking means 104c when engaged, pivot around the hinge axis 103 (which is essentially identical to the axis of rotation X') when the hood 102 is opened / closed. Such an arrangement provides protection for the motor assembly 104, particularly against heat.Thus, this particular arrangement advantageously extends the life of the engine assembly 104, reduces the risk of potential failures within said engine assembly, and reduces the manufacturing costs of said engine assembly, as well as the weight of said engine assembly, since it is then possible to use materials requiring lower temperature resistance than when the engine assembly 104 is more exposed to radiation from the core 60.

[0052] The motor assembly 104 here comprises an electric motor 104a with a motor shaft parallel to the axis of rotation X' and, preferably, a gearbox 104b which extends generally in line with the electric motor 104a and which extends generally parallel to the axis of rotation X'. Preferably, the gearbox 104b extends coaxially with the axis of rotation X' (and therefore with the hinge axis 103) to limit the overall size of the motor assembly 104. The gearbox 104b is preferably of the compact type and with a high degree of meshing, and comprises, for example, a gear system including planetary gear trains arranged in series.

[0053] To facilitate the movement of the hood 102, the gear ratio of the gear system of the gearbox 104b is greater than 1. The installation of a gear system where the gear ratio is higher makes it possible to reduce the torque required to open and close the hood 102.

[0054] In this example, the gearbox 104b comprises a gear system having an input pinion fixed to the motor shaft and an output pinion fixed to the drive shaft 106.

[0055] The electric motor 104a of the assembly 104 is electrically powered by an electrical source and controlled in rotation by the control unit.

[0056] The electric motor 104a is thus arranged globally coaxially with the axis of the hinge 103 so as to provide a significant space saving and better protection, in particular against heat.

[0057] The motor assembly 104 may also include locking means 104c for holding the hood 102 in the open position, or for preventing the hood 102 from closing, particularly in the event of a loss of power to the electric motor. These locking means 104c may thus have a function of holding the hoods 102 in their open position, and / or of securing the hoods in the event of a system failure. The locking means 104c may, for example, take the form of a mechanical brake system that can be actuated at any time during the stroke or a mechanical locking system that can preferably be actuated only in the fully deployed position. It is conceivable that the lock is actuated automatically in the fully deployed position and that it is deactivated by the action of a current-powered solenoid, or that it is actuated and deactivated by the action of the solenoid.It should be noted that in the event of a loss of the electrical source, consideration could be given to implementing a rheostatic braking system (i.e., discharge resistors) which would control the descent of the hood 102 at a speed slow enough not to be dangerous for the operators in order to prevent the hood 102 from remaining stuck in the fully open position.

[0058] Thus, the implementation of a system for holding the hoods 102 in the open position is no longer necessary. However, for reasons of redundancy and safety, the nacelle 100 could be equipped, in addition to the engine assembly 104, for each hood 102, with a holding system (not shown) used only during maintenance operations. Such a holding system is, for example, fixed between the core 60 and the hood 102. Such a holding system can, for example, take the form of a retaining rod, also called a retaining rod or support arm.

[0059] To know the position of each hood 102, and thus be able to stop the motor assembly 104 when necessary, the motor assembly 104 can be equipped with a position sensor which is arranged to detect the angular position of said drive shaft 106 and therefore of said associated hood 102.

[0060] For safety reasons and to prevent the cover 102 from going below the closed position or beyond the open position, the motor assembly 104 may include stops limiting the rotational movement of the drive shaft 106. It is therefore possible to implement a stop that stops the rotation of the drive shaft when it has reached the position corresponding to the closed position of the cover 102, and a stop that stops the rotation of the drive shaft when it has reached the position corresponding to the open position of the cover 102. For example, the stops may be digital stops that are programmed for each electric motor 104a. In one variant, the stops can be mechanical stops arranged in the hinge axes or stops fixed on the mast which apply an action on the hood 102 when the open or closed position of the hood 102 has been reached.

[0061] According to one configuration, the electric motor of the assembly 104a is powered by electrical energy from the aircraft's electrical network (itself connected to a local electrical network on the ground), or by a battery, for example, which can be located remotely from the mounting mast 16, said battery being either in the aircraft or on the ground.

[0062] As an alternative to the electric motor as described above, the motor assembly 104 may include a hydraulic motor powered by hydraulic energy from an aircraft cooling system, such as an air conditioning system, or by an external hydraulic energy source, which may be located away from the towing mast 16.

[0063] In addition, the motor assembly 104 comprising a hydraulic motor can also be powered by an electric motor, hydraulic pump and reservoir assembly supplied by electrical energy from the aircraft's electrical network (itself connected to a local ground electrical network), or by a battery, for example, which can be located remotely from the towing mast 16, said battery being either in the aircraft or on the ground.

[0064] The invention has been described above for hoods 102 surrounding the core 60 of the drive system 50. The invention can also be applied to other types of hoods, and in particular to maintenance hoods.

Claims

Demands

1. Nacelle (100) for a propulsion system (50) of an aircraft (10), said nacelle (100) extending about a longitudinal axis (X) and comprising: - at least one cowl (102) mounted hinged between a closed position and an open position about a hinge axis (103) which extends parallel to the longitudinal axis (X), - for each cowl (102), at least one motor assembly (104) comprising an actuating shaft (106) movable in rotation about said hinge axis (103) and wherein said actuating shaft (106) is configured to move said associated cowl (102) between said closed position and said open position.

2. Nacelle (100) according to claim 1, characterized in that said motor assembly (104) comprises a motor (104a) with a motor shaft globally parallel to said hinge axis (103) and a gear system (104b) having an input pinion integral with the motor shaft and an output pinion integral with the drive shaft (106), where the gear ratio of the gear system (104b) is greater than 1.

3. Nacelle (100) according to claim 2, characterized in that said motor (104a) is an electric motor.

4. Nacelle (100) according to claim 2, characterized in that said motor (104a) is a hydraulic motor.

5. Nacelle (100) according to any one of claims 1 to 4, characterized in that said motor assembly (104) comprises locking means (104c) configured to lock and unlock the position of said hood (102).

6. Nacelle (100) according to any one of claims 2 to 5, characterized in that said motor (104a) is intended to be attached to a mounting mast (16) of said aircraft (10) and in that said drive shaft (106) is attached to the cowling (102).

7. Nacelle (100) according to any one of claims 2 to 5, characterized in that said engine (104a) is fixed to the cowling (102) and in that said drive shaft (106) is intended to be fixed to a mounting mast (16) of said aircraft (10).

8. Nacelle (100) according to claim 7, characterized in that said hood (102) comprises an inner wall and an outer wall which together define a housing and in that said motor (104) is fixed in said housing.

9. Nacelle (100) according to any one of claims 1 to 8, characterized in that each hood (102) comprises two motor assemblies (104) spaced apart along said hinge axis (103).

10. Propulsion system (50) for an aircraft (10) comprising a core (60) and a nacelle (100) according to any one of claims 1 to 9 surrounding the core (60).

11. Aircraft (10) comprising at least one propulsion system (50) according to claim 10.

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