Turbojet engine nacelle including a single movable frame of a cascade thrust reverser and passages of ancillaries

Abstract

A turbojet engine nacelle having a cascade-type thrust reverser includes a movable frame surrounding a cold air flow path, guided axially by longitudinal rails fixed to an intermediate casing surrounding the cold air flow path and supporting cascades of thrust-reversal guide vanes and mobile rear cowls. The nacelle has a passage of ancillaries opening radially towards the outside of the movable frame, in a zone with no bearing structure passing radially across the cold air flow path. The movable frame is cut in an axial plane at the passage for the passage of ancillaries, and each edge of the cut of the movable frame is connected to the intermediate casing by a slide rail fitted on a longitudinal rail arranged each on one side of this passage.

Claims

1. A nacelle for a turbojet engine including a cascade thrust reverser, the nacelle comprising: a movable frame surrounding a cold air flow path, guided axially by longitudinal rails fastened on an intermediate casing surrounding the cold air flow path, the movable frame supporting thrust reverser cascades and rear cowls; and a passage of ancillaries opening radially outwardly of the movable frame in an area including no support structure passing radially through the cold air flow path, the passage of ancillaries disposed at a 6 o'clock position of the nacelle opposite to a pylon for supporting the turbojet engine, wherein the movable frame is cut in an axial plane at the passage of ancillaries, and each edge of a section of the movable frame is connected to the intermediate casing by a slide rail adjusted on the longitudinal rails, each of the slide rails disposed on a side of the passage of ancillaries.

2. The nacelle according to claim 1 further comprising a shutter plate closing a space between the longitudinal rails receiving the slide rails.

3. The nacelle according to claim 2, wherein the shutter plate includes a bore receiving the passage of ancillaries.

4. The nacelle according to claim 3, wherein the shutter plate extends relative to a rear of the thrust reverser cascades by a distance equal to a stroke of the movable frame.

5. The nacelle according to claim 4, wherein a rear of the rear cowls has an opening forming a passage receiving a rear end of the shutter plate when the thrust reverser is closed.

6. The nacelle according to claim 2, wherein, when the thrust reverser is being opened, the thrust reverser cascades are adjusted on the slide rails and the shutter plate is adjusted between the slide rails so as not to have a cold air radial passage outside the thrust reverser cascades.

7. The nacelle according to claim 1 further comprising a fixed outer fairing disposed rearward of the passage of ancillaries, the fixed outer fairing being adjusted on an outer shape of the rear cowls.

8. The nacelle according to claim 7 further comprising a shutter plate closing a space between the longitudinal rails receiving the slide rails, wherein the shutter plate and the fixed outer fairing form a single piece.

9. The nacelle according to claim 8, wherein the rear cowls include an elongated window receiving the fixed outer fairing when the thrust reverser is closed.

10. The nacelle according to claim 8 further comprising connecting rods passing radially inside the fixed outer fairing, each of the connecting rods connecting two locks, each of the locks fastened on an end of one of the rear cowls.

11. The nacelle according to claim 1, wherein the passage of ancillaries includes drains disposed vertically at a bottom of the nacelle.

Description

DRAWINGS

(1) In order that the disclosure may be well understood, there will now be described various forms thereof, given by way of example, reference being made to the accompanying drawings, in which:

(2) FIG. 1 is a perspective view of a turbojet engine nacelle according to the prior art, including a circular frame of the “0-Duct” type, in which the thrust reverser is closed;

(3) FIG. 2 is a perspective view of the turbojet engine nacelle of FIG. 1 with the thrust reverser opened;

(4) FIG. 3 is a perspective view of a portion of the turbojet engine nacelle of FIG. 1 showing the position of a passage of ancillaries that is provided below the nacelle;

(5) FIG. 4 is a perspective view of a portion of a nacelle according to the present disclosure, with the thrust reverser closed;

(6) FIG. 5 is a perspective view of a portion of the nacelle according to the present disclosure, with the thrust reverser opened;

(7) FIG. 6 shows a variant of the nacelle with the opened thrust reverser comprising a fixed outer fairing according to the present disclosure; and

(8) FIG. 7 is a cross-sectional view of the nacelle in a section which is downstream of the movable frame according to the present disclosure.

(9) The drawings described herein are for illustration purposes only and are not intended to limit the scope of the present disclosure in any way.

DETAILED DESCRIPTION

(10) The following description is merely exemplary in nature and is not intended to limit the present disclosure, application, or uses. It should be understood that throughout the drawings, corresponding reference numerals indicate like or corresponding parts and features.

(11) FIG. 1 shows a nacelle of a bypass turbojet engine supported by an engine pylon 2 disposed at the 12 o'clock position, including towards the front, which is indicated by the arrow AV, a fixed intermediate casing 10 surrounding the annular cold air flow path, which supports by actuating cylinders 7 for actuating a movable frame forming a closed rigid contour, slidably mounted on rails disposed in the vicinity of the engine pylon 2.

(12) The movable frame supports, forwards, a succession of cascades 4 forming panels surrounding the nacelle, then rearwards, a rear cowl 6.

(13) In the closing position of the thrust reverser, lateral air passages surrounding the cold air flow are closed by the cowl 6, the cascades 4 being inserted between the intermediate casing 10 and a front cowl of the nacelle which is not represented.

(14) In the opening position of the thrust reverser shown in FIG. 2, the movable frame moves back on the guide rails thereof under the effect of actuating cylinders 7, the cascades 4 coming opposite to the lateral passages, and inner flaps being deployed in the cold air flow path to direct the flow towards these cascades.

(15) FIG. 3 shows in detail the guide of the movable frame including, starting radially inwardly, a fixed rail 8 linked to the intermediate casing 10, then a movable slide rail 14 extending rearwardly by a longitudinally elongated plate 16 which is adjusted between two cascades 4.

(16) In order to provide for a passage of ancillaries 18, such as pressurized fluid pipes, drains or electric cables, in the 6 o'clock position, vertically downwardly, it would be desirable to radially pass different pipes, drains, and electric cables of ancillaries 18 through the elongated plate 16 of the slide rail 14. In particular, the passage of ancillaries may include drains 18 for discharging fluids, disposed vertically at the bottom of the nacelle.

(17) This arrangement cannot be simply carried out because the conduits and cables of ancillaries 18 should pass radially through the movable frame 5 equipped with the cascades 4 thereof, which slide axially during the movements of the thrust reverser.

(18) FIG. 4 shows a guide system at the 6 o'clock position of the movable frame 5 according to the present disclosure, including two guide rails 8a, 8b slightly spaced apart, each receiving a slide rail 14a, 14b. The movable frame 5 is cut according to an axial plane, each edge of this section being fastened to a slide rail 14a, 14b engaged in a rail 8a, 8b, which allows obtaining a good rigidity of this movable frame 5 by passing through the intermediate casing 10.

(19) An elongated shutter plate 20 disposed between the two rails 8a, 8b and linked to these rails, includes a bore 21 disposed on the median axis thereof constituting a passage of the ancillaries 18. In this manner, the slide rails 14a, 14b slide on each side of the shutter plate 20, by leaving the passage of the ancillaries 18 immobile which allows making, in a simple manner, the pipes and cables of these ancillaries.

(20) During the backward movement of the movable frame 5 shown in FIG. 5, each slide rail 14a, 14b strongly exits towards the downstream of the rail 8a, 8b thereof, by leaving at the end of the movement a small portion engaged with this rail, allowing obtaining a sufficient hold of the movable frame 5 with its equipment fastened thereon. In practice as shown in this example, for an axial stroke of 500 mm, it is possible to keep an engagement of the slide rail 14a, 14b on the rail 8a, 8b greater than 20% in order to obtain a sufficient span.

(21) Alternatively, it is also possible to provide for inner clearances in the nacelle allowing obtaining, in the fully open position of the thrust reverser, an engagement of each slide rail 14a, 14b over the entire length of the rail 8a, 8b thereof.

(22) The shutter plate 20 disposed parallel to the main axis of the nacelle, has a rear end 26 which extends inside the movable cowl 6, by exiting through a window of this cowl because of the rear curvature of the cowl which approaches this main axis. In addition, an aerodynamic rear appendage covering the rear window of the cowl, also called “beaver tail,” in order to improve the aerodynamics of the nacelle.

(23) In this manner, in the thrust reversal position shown in FIG. 5, the shutter plate 20, bordered by the two slide rails 14a, 14b thereof, completely closes the space disposed between the two adjacent cascades 4. The entire cold air flow rejected radially outwardly then passes through the thrust reverser cascades 4, which improves the braking thrust.

(24) FIGS. 6 and 7 show a fixed outer fairing 30 forming an elongated plate disposed below the rails 8a, 8b, behind the passage of the ancillaries 18, which is fastened to the intermediate casing 10 so as to remain immobile during the sliding of the movable frame 5.

(25) The rear cowl 6 has a forwardly open elongated window 32, corresponding to the contour of the fixed outer fairing 30, which with the open thrust reverser is disposed in alignment with this outer fairing, just behind it.

(26) The fixed outer fairing 30 closes the passage between the two adjacent cascades when the thrust reverser is open, to improve the braking thrust. When the thrust reverser is closed, the fixed outer fairing 30 is adjusted (or shaped) in the elongated window 32 of the rear cowl 6, in order to find a good aerodynamic of the outer surfaces of the nacelle, or to conform to the outer shape of the rear cowl 6.

(27) As shown in FIG. 7, the end of each rear cowl 6a, 6b includes locks 34 for fastening on the movable frame 5, which are unlocked to open these cowls during maintenance operations. Connecting rods 36 passing radially inside the fixed outer fairing 30 and rails 8a, 8b, connect two locks 34 which are transversely aligned when these locks are closed, to give the rear cowls 6 a good rigidity at the elongated window 32.

(28) Unless otherwise expressly indicated herein, all numerical values indicating mechanical/thermal properties, compositional percentages, dimensions and/or tolerances, or other characteristics are to be understood as modified by the word “about” or “approximately” in describing the scope of the present disclosure. This modification is desired for various reasons including industrial practice, material, manufacturing, and assembly tolerances, and testing capability.

(29) As used herein, the phrase at least one of A, B, and C should be construed to mean a logical (A OR B OR C), using a non-exclusive logical OR, and should not be construed to mean “at least one of A, at least one of B, and at least one of C.”

(30) The description of the disclosure is merely exemplary in nature and, thus, variations that do not depart from the substance of the disclosure are intended to be within the scope of the disclosure. Such variations are not to be regarded as a departure from the spirit and scope of the disclosure.