NACELLE FOR AN AIRCRAFT ENGINE

Abstract

NACELLE FOR AN AIRCRAFT ENGINE The invention relates to a nacelle (100) for an aircraft engine system. The nacelle (100) has an articulated front hood (102), an articulated rear hood (104) and having a first guide element (106) delimiting a guide zone between a first limit (106a) and a second limit (106b), and a connecting rod (110) with a first end (110a) articulated on the front hood (102) and a second end (110b) having a second guide element (111) guided by the first guide element (106) where in the closed position of the front hood (102) and the rear hood (104), the second guide element (111) is at the level of the first limit (106a) and where in an intermediate position of the front hood (102) between the closed position and the open position and in the closed position of the rear hood (104), the second guide element (111) is at the level of the second limit (106b).With this arrangement, the rear hood is opened by manipulating the front hood. 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 which comprises two movable cowlings connected to each other by an opening assist rod, an aircraft propulsion system comprising such a nacelle and an aircraft comprising at least one such propulsion system. PREVIOUS STATE OF THE ART

[0002] An aircraft propulsion system classically comprises a core surrounded by a nacelle which forms, among other things, an aerodynamic surface around the core and the propulsion system is generally fixed under a wing of the aircraft by a mounting mast.

[0003] The nacelle includes hoods which are mounted articulated by means of hinges and which are locked in the closed position by a locking system accessible from the outside by a technician.

[0004] Typically, from front to rear of the nacelle, in the case of a turbofan engine, there is an air inlet, a fan, and a cowling for a thrust reverser system, and the air inlet and fan are enclosed. Typically, from front to rear of the nacelle. In this embodiment, each cowling for the thrust reverser system consists of a single unit, which can be relatively heavy and bulky.

[0005] In the case of an engine with an unfaired fan, called an "open fan", there is a fan and a hood which is at the rear of the fan which is not faired.

[0006] For maintenance purposes, it is necessary to be able to open the hoods by pivoting them around the hinge axes. To open a hood, in particular the hood of the thrust reverser system, the technician unlocks the locking system and lifts the hood; the reverse operation closes the hood.

[0007] Struts can be fitted to assist in opening a cowling. However, with the increasing size of engines, the opening angle of the cowling, in particular the cowling of a thrust reverser system, is limited by the fact that its rear part is obstructed by the presence of the wing against which it abuts.

[0008] It is therefore necessary to find an arrangement that facilitates the opening of the hood. Description of the invention

[0009] An object of the present invention is to provide a nacelle for an aircraft propulsion system which comprises two hinged cowlings connected to each other by a connecting rod to assist with opening.

[0010] To this end, a nacelle for an aircraft propulsion system is proposed, said nacelle comprising:

[0011] - a front hood mounted articulated around a front hinge axis between a position closed and an open position,

[0012] - a rear hood mounted hinged around a rear hinge axis between a closed position and an open position, and presenting a first guiding element delimiting a guiding zone between a first limit and a second limit, and

[0013] - a connecting rod having a first end mounted articulated on the front hood and a second end having a second guide element arranged to be guided by the first guide element between the first limit and the second limit where in the closed position of the front hood and the rear hood, the second guide element is at the level of the first limit and where in an intermediate position of the front hood between the closed position and the open position and in the closed position of the rear hood, the second guide element is at the level of the second limit.

[0014] With such an arrangement, the rear hood is opened by manipulating the front hood and it is possible to dissociate the opening angle of the rear hood from the opening angle of the main front hood.

[0015] Advantageously, the first guide element is a guide groove extending between the first limit and the second limit and the second guide element is a shaft mounted movable in the guide groove.

[0016] Advantageously, the guide groove takes the form of an arc of a circle.

[0017] According to a particular embodiment, the rear hood is a hood of a system thrust reverser.

[0018] According to another particular embodiment, the front hood and the rear hood together form a hood of a thrust reverser system.

[0019] The invention also proposes a propulsion system for an aircraft comprising a core and a nacelle according to one of the preceding variants.

[0020] The invention also proposes an aircraft comprising at least one propulsion system according to the previous variant. Brief description of the drawings

[0021] 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:

[0022] [Fig. 1] is a side view of an aircraft comprising a nacelle according to the invention,

[0023] [Fig. 2] is a schematic side view of a nacelle according to the invention,

[0024] [Fig. 3] is a partial rear view of a nacelle according to the invention in position closed with both hoods,

[0025] [Fig.4] is a view similar to that of [Fig.3] in the intermediate position of the front hood and in the closed position of the rear hood, and

[0026] [Fig.5] is a view similar to that of [Fig.3] in the open position of both hoods.

[0027] DETAILED STATEMENT OF IMPROVEMENTS

[0028] In the following description, terms relating to a position are taken with reference to an aircraft in a forward position as shown in [Fig.1], and where arrow F shows the direction of forward movement of the aircraft in flight.

[0029] Fig. 1 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 propulsion system 50.

[0030] The drive system 50 comprises a core 60 (shown in dotted lines in [Fig.1]) and a nacelle 100 according to the invention surrounding the core 60. In the various figures, only one side of the nacelle 100 is shown, but the same arrangement can be put in place on both sides of the nacelle 100.

[0031] 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.

[0032] The nacelle 100 has a vertical median plane P of symmetry which coincides with the vertical plane XZ and, here the nacelle 100 has on either side of the vertical median plane P a front hood 102 and a rear hood 104. Thus there is on each side of the vertical median plane P a front hood 102 and a rear hood 104.

[0033] In the case of a turbofan engine, the front cowl 102 can be a fan cowl and the rear cowl 104 can be a cowl of a thrust reverser system.

[0034] According to a particular embodiment, in the case of a turbofan engine, the thrust reverser system cowling is separated into two sub-cowlings which are then the front cowling 102 and the rear cowling 104. The front cowling 102 and the rear cowling 104 thus together form the cowling of the thrust reverser system.

[0035] Similarly, according to another particular embodiment, in the case of an engine with an unfaired fan, known as an "open fan," the cowling at the rear of the fan is divided into two sub-cowlings, which are then the front cowling 102 and the rear cowling 104. The front cowling 102 and the rear cowling 104 thus together form the cowling of gondola 100.

[0036] The invention described herein can therefore be applied to a blower hood and a hood of a thrust reverser system, or to a hood of a thrust reverser system consisting of two hoods, or to any other type of hinged hoods of a nacelle.

[0037] The front hood 102 is just in front of the rear hood 104 and each hood 102, 104 takes the form of a half-cylinder so as to form together a cylinder surrounding the core 60. The front hood 102 and the rear hood 104 are joined at a contact plane that is generally perpendicular to the longitudinal axis X.

[0038] The core 60 in the illustrated example takes the form of a double-flow turbojet with a fan at the front, but, as seen previously, the invention applies to other types of engine.

[0039] Each front hood 102 is hinged on a structure which can be a structure of the drive system 50 or of the attachment mast 16. The hinge of the front hood 102 is made around a front hinge axis 103 and it is movable between a closed position in which the front hood 102 is tightened around the core 60 and an open position in which the front hood 102 is moved away from the core 60. In the closed position, the two front hoods 102 come against a lower spar 62 of the nacelle 100. Each front hood 102 thus comes on either side of the lower spar 62 which is at the level of the lower part of the nacelle 100, at 6 o'clock.

[0040] Similarly, each rear hood 104 is mounted articulated on a structure which can be a structure of the drive system 50 or of the attachment mast 16. The articulation of the rear hood 104 takes place around a rear hinge axis 105 between a closed position in which the rear hood 104 is tightened around the core 60 and an open position in which the rear hood 104 is moved away from the core 60. In the closed position, the two rear hoods 104 come to rest against the lower spar 62 of the nacelle 100. Each rear hood 104 thus comes to rest on either side of the lower spar 62 which is at the level of the lower part of the nacelle 100, at 6 o'clock.

[0041] The hinge axes 103 and 105 are arranged in the upper part of each hood 102, 104 and the hoods 102 and 104 are mounted articulated on the mounting mast 16 around the associated hinge axis 103, 105.

[0042] To lock each hood 102, 104 in the closed position, the platform 100 includes locking systems 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, 104 in the closed position, or an unlocked position in which it does not lock the associated hood 102, 104, which is then free to move from the closed position to the open position and vice versa.

[0043] Figure 2 shows the drive system 50 in side view, and Figures 3 to 5 show the starboard side of the nacelle 100 with, in Figure 3, both hoods 102 and 104 in the closed position, in Figure 4, the front hood 102 in an intermediate position between the closed and open positions and the rear hood 104 in the closed position, and in Figure 5, both hoods 102 and 104 in the open position. The intermediate position corresponds to the maximum opening position that the front hood 102 can reach before the rear hood 104 begins to open.

[0044] On its inner face, that is, the face oriented towards the core 60, the rear cover 104 has a guide groove 106 extending between a first limit 106a and a second limit 106b. In the closed position, the guide groove 106 lies in a plane perpendicular to the longitudinal axis X, that is, parallel to the contact plane. The first end 106a is above the second end 106b.

[0045] In the form shown in Figs. 3 to 5, the guide groove 106 takes the form of an arc of a circle around the longitudinal axis X.

[0046] For each pair of front hoods 102 and rear hoods 104, the nacelle 100 also includes a connecting rod 110 which has a first end 110a which is mounted articulated on the front hood 102 at the level of its inner face, in particular by a pivot joint.

[0047] The second end 110b of the connecting rod 110 carries a shaft 111 which is movably mounted in the guide groove 106 and can thus move freely in translation and rotation within the guide groove 106 between the two limits 106a-b, which it cannot exceed. The connection between the shaft 111 and the guide groove 106 is preferably a ball joint.

[0048] When the two hoods 102 and 104 are in the closed position ([Fig.3]), the second end 110b of the connecting rod 110, and more particularly the shaft 111, are at the level of the first limit 106a, that is to say at the bottom of the guide groove 106.

[0049] By opening the front hood 102 ([Fig.4]), the rear hood 104 remains in position closed, the second end 110b of the connecting rod 110 and therefore the shaft 111 move along the guide groove 106 until reaching the second limit 106b corresponding to the intermediate position of the front hood 102.

[0050] By continuing to open the front hood 102, the second end 110b of the connecting rod 110 and therefore the shaft 111 can no longer move relative to the guide groove 106, which causes the rear hood 104 to lift and then open.

[0051] Thus, depending on the opening angle of the front hood 102, the rear hood 104 remains closed or opens under the impulse of said front hood 102. The technician therefore no longer needs to manipulate the rear hood 104 and can open both hoods 102 and 104 simply by operating the front hood 102. The opening of the rear hood 104 can also be offset from that of the front hood 102 and their opening angles are different.

[0052] The length of the guide groove 106 between the two limits 106a-b allows a delay to be created in the opening of the rear hood 104 and the opening angle of each hood 102, 104 to be managed.

[0053] Furthermore, if the thrust reverser system cover is separated into two covers, constituting the front cover 102 and the rear cover 104 respectively, handling the front cover 102 reduces the workload for the technician at least up to the second limit 106b. In addition, separating the thrust reverser system cover into two covers 102 and 104 allows the front cover 102 to be opened at a greater angle than in the prior art, because it is not obstructed by the rear cover 104, which abuts against the wing.

[0054] According to a particular embodiment, the intermediate position of the front hood 102 corresponds to an angle of 38°, the open position of the front hood 102 corresponds to an angle of 75° and the open position of the rear hood 104 corresponds to an angle of 30°.

[0055] Generally, the rear hood 104 has a first guide element 106 delimiting a guide zone between a first limit 106a and a second limit 106b and the connecting rod 110 has at its second end 110b, a second guide element 111 arranged to be guided by the first guide element 106 between the first limit 106a and the second limit 106b and where in the closed position of the front hood 102 and the rear hood 104, the second guide element 111 is at the level of the first limit 106a and where in an intermediate position of the front hood 102 between the closed position and the open position and in the closed position of the rear hood 104, the second guide element 11 is at the level of the second limit 106b.

[0056] In the case of the invention presented here, the first guiding element is the guide groove 106 which extends between the first limit 106a and the second limit 106b and the second guiding element 111 is the shaft 111 mounted movable in the guide groove 106.

[0057] Of course, it is possible to provide for other arrangements, for example, it is possible to provide for a slide attached to the second end 110b and mounted to slide on a rail attached to the rear cover 104 between two stops fixed on the rail and constituting the two limits.

Claims

Demands

1. A nacelle (100) for a propulsion system (50) of an aircraft (10), said nacelle (100) comprising: - a front cowl (102) mounted hinged about a front hinge axis (103) between a closed position and an open position, - a rear cowl (104) mounted hinged about a rear hinge axis (105) between a closed position and an open position and having a first guide element (106) defining a guide zone between a first limit (106a) and a second limit (106b), and - a connecting rod (110) having a first end (110a) mounted hinged on the front cowl (102) and a second end (110b) having a second guide element (111) arranged to be guided by the first guide element (106) between the first limit (106a) and the second limit (106b) or in the closed position of the cowl front (102) and rear hood (104),the second guide element (111) is at the level of the first limit (106a) and where in an intermediate position of the front hood (102) between the closed position and the open position and in the closed position of the rear hood (104), the second guide element (111) is at the level of the second limit (106b).

2. Nacelle (100) according to claim 1, characterized in that the first guide element is a guide groove (106) extending between the first limit (106a) and the second limit (106b) and in that the second guide element (111) is a shaft (111) mounted movably in the guide groove (106).

3. Nacelle (100) according to claim 2, characterized in that the guide groove (106) takes the form of an arc of a circle.

4. Nacelle (100) according to any one of claims 1 to 3, characterized in that the rear hood (104) is a hood of a thrust reverser system.

5. Nacelle (100) according to any one of claims 1 to 3, characterized in that the front hood (102) and the rear hood (104) together form a hood of a thrust reverser system.

6. Propulsion system (50) for an aircraft (10) comprising a core (60) and a nacelle (100) according to any one of claims 1 to 5 surrounding the core (60).

7. Aircraft (10) comprising at least one propulsion system (50) according to claim 6.

Images