Main structure for carrying struts of an aircraft power plant, the rear part of which is formed by a set of connecting rods

Abstract

The invention relates to a main structure (1) for a strut carrying an aircraft powerplant comprising a front part (8) intended to be coupled to the aircraft powerplant and a rear part (9) intended to be coupled to the aircraft structure, the front part (8) being formed by a box comprising upper longitudinal members, lower longitudinal members and transverse panels. A main rib (10) is located at the interface between the front part (8) and the rear part (9). The rear part (9) is formed by a set of four connecting bars (13, 14). A first end (16) of each connecting bar is coupled to the front part (8) of the main structure and a second end (17) of each connecting bar (13, 14) is coupled to a separate interface for fastening to the aircraft structure. This allows a substantial simplification of the main structure for a strut carrying an aircraft powerplant which can have advantages in particular in terms of cost, mass and simplicity of implementation and integration.

Description

Technical Field

[0001] This invention relates to the field of struts for supporting aircraft power units. Background Technology

[0002] In an aircraft, a strut is an element that forms a joint between a propulsion assembly or power unit and an aircraft structure, such as at its wing unit or its fuselage.

[0003] The strut comprises the primary structure that allows the absorption and transmission of forces acting on it, and secondary structures that generally correspond to the aerodynamic fairing, which has no structural function. The fairing or secondary structure also makes it possible to cover the cables and ducts that connect the power unit to the rest of the aircraft.

[0004] The main structure comprises a box-like general structure in a known manner. This composition of the main structure gives the struts a high degree of rigidity and strength, which is necessary for transmitting forces between the power plant and the aircraft structure while ensuring low mass.

[0005] The main structure of the strut also includes attachments intended to first integrate the strut into the aircraft structure and then into the power unit.

[0006] The main structure of an aircraft strut can have complex shapes, including box-shaped truncated pyramids, as shown in the attached image. Figure 1 and 2 As shown in the image.

[0007] However, this conventional structure is complex. Producing the main structure using existing technology is expensive due to the complexity of machining and assembling its component parts, as well as the large size of these parts. Summary of the Invention

[0008] The purpose of this invention is to provide a main structure for an aircraft strut, which includes an optimized structure, particularly in terms of its production cost.

[0009] Therefore, the present invention relates to a main structure for supporting an aircraft power unit strut, comprising a front portion intended to be integrated with the aircraft power unit and a rear portion intended to be integrated with the aircraft structure. The front portion is formed by a housing comprising an upper longitudinal member, a lower longitudinal member, and a transverse panel. The main structure includes a main rib located at the interface between the front and rear portions. The rear portion is formed by a set of connecting rods, each connecting rod including a first end and a second end, the first end of each connecting rod being integrated with the front portion of the main structure, and the second end of each connecting rod being integrated with a separation interface for fastening to the aircraft structure. There are four connecting rods, and the intersection of the main ribs and the front portion of the main structure forms a quadrilateral including four corners, with a connecting rod integrated with the front portion substantially at each of said corners.

[0010] The rear section, formed by a set of connecting rods, provides a significant simplification of the main structure for supporting the aircraft's power unit. The dimensions of some components (longitudinal members, transverse panels) are reduced. Therefore, this invention allows for a substantial reduction in the cost of manufacturing the main structure. Furthermore, it simplifies the integration of the main structure into the aerodynamic fairing (secondary structure).

[0011] At the point of separation, each connecting rod can be connected to the front using a hinged or ball joint.

[0012] Each connecting rod may be formed of a flat strip or two parallel flat strips or a tube with a triangular, square, rectangular or circular cross-section for at least most of its length.

[0013] This set of connecting rods may include a so-called lower connecting rod and a so-called upper connecting rod. The lower connecting rod and the upper connecting rod may have different cross-sections for at least a majority of their respective lengths. The lower connecting rod may have a different length than the upper connecting rod.

[0014] The main rib can be extended beyond the upper longitudinal member at the front of the main structure to form a plane for fastening to the aircraft structure.

[0015] The intersection of the main rib and the plane parallel to the lower longitudinal member may be inclined about the transverse direction, which is orthogonal to the longitudinal direction in the plane, which corresponds to the extension direction of the front part of the main structure.

[0016] The front transverse panels may each include an extension beyond the main rib, and each extension includes at least one eyelet for fastening the connecting rod.

[0017] Each interface for fastening to the second end of the connecting rod for fastening to the aircraft structure may include a hinged or ball joint to the second end of the connecting rod, and a plate for fastening to the aircraft structure.

[0018] The present invention also relates to an aircraft comprising at least one wing and at least one power unit mounted beneath the wing, the power unit being coupled to the structure of the wing by means of a load-bearing strut comprising the main structures as described above.

[0019] Other features and advantages of the present invention will become apparent from the following description. Attached Figure Description

[0020] The accompanying drawings provide non-limiting examples:

[0021] – Figure 1 It is a three-dimensional schematic view of a first example of the main structure of an aircraft power plant support strut as known from the prior art;

[0022] – Figure 2 This is a three-dimensional schematic view of a second example of the main structure of an aircraft power plant support strut, as known from the prior art;

[0023] – Figure 3 This is a three-dimensional schematic view of the main structure of the aircraft power plant support strut according to an embodiment of the present invention;

[0024] – Figure 4 Showing from another perspective Figure 3 The main structure of the aircraft power plant support strut;

[0025] – Figure 5 It is shown as a top view. Figure 3 and 4 A three-dimensional schematic view of the main structure of the aircraft power plant support strut, in which the upper longitudinal members of the main structure are in the foreground;

[0026] – Figure 6 Various cross sections are shown as sectional views, which can be envisioned for use in the connecting rods used in this invention;

[0027] – Figure 7 yes Figures 3 to 5 A detailed three-dimensional partial view of the main structure of the aircraft power plant support strut;

[0028] – Figure 8 Showing with Figure 7 A similar view of a variant of the main structure of the aircraft power plant support strut according to an embodiment of the present invention. Detailed Implementation

[0029] Figure 1 The main structure of the aircraft power plant strut is shown as known from the prior art.

[0030] In an aircraft, a strut is an element that forms the joint between the propulsion assembly or power unit, including the engine and nacelle, and the aircraft structure, generally located at its wing unit or its fuselage.

[0031] The strut includes the main structure that allows the absorption and transmission of forces acting on the strut, and the secondary structure that generally corresponds to the aerodynamic fairing, which has no structural function.

[0032] The main structure 1 comprises several substantially parallel ribs 2. To form the main structure, upper longitudinal members 3, lower longitudinal members 4, and transverse panels 5 are fastened to the ribs 2, making it possible to obtain a box-like structure. Figure 1In this design, some of the transverse panels 5 are not shown to leave the internal structure of the main structure 1 visible. This box-like structure gives the main structure, and thus the supports, a high degree of rigidity and strength, which is necessary to transmit forces between the power unit and the aircraft structure.

[0033] The main structure of the strut also includes attachments intended to first integrate the strut into the aircraft structure and then into the power unit. More specifically, the main structure includes interfaces for fastening to the aircraft 6 and interfaces for fastening to the power unit 7.

[0034] The main structure consists of two parts: the front part 8, which is generally integrated with the power plant, and the rear part 9, which is generally integrated with the aircraft.

[0035] To eliminate the use of certain ribs, longitudinal members 3, 4 and / or transverse panels 5 can be used, which are reinforced by ribs or have a honeycomb structure (e.g., ISOGRID (registered trademark) type).

[0036] Figure 2 A second example of the main structure of an aircraft power plant support strut according to the prior art is shown. In this example, the upper longitudinal member 3, the lower longitudinal member 4, and the transverse panel 5 have a honeycomb or perforated configuration, thereby allowing for significant mechanical properties while providing constrained mass.

[0037] The main structure extends along a general direction called the longitudinal direction L. The transverse direction T is defined as orthogonal to the longitudinal direction L and parallel to the surface of the lower longitudinal member 4. The vertical direction V is orthogonal to both the longitudinal direction L and the transverse direction T.

[0038] and Figure 1 Compared to the structure, it is used in Figure 2 The number of ribs in the example is significantly less. The main structure thus generally comprises the main rib 10. The main rib 10 is located at the interface between the front part 8 and the rear part 9 of the main structure. The main rib 10 has an extension 11 that extends beyond the upper longitudinal member 3, i.e., on the outside of the box formed by the main structure 1.

[0039] The extension 11 of the main rib 10 forms a plane for securing the strut to the aircraft structure. In the illustrated example, the main rib 10 and thus its extension 11 extend substantially vertically and are inclined about the transverse direction T. Therefore, the main rib 10 is not orthogonal to the longitudinal direction L, which corresponds to the general direction in which the strut extends. In other words, the main rib 10 intersects the horizontal plane parallel to the lower longitudinal member about the transverse direction, which is orthogonal in that plane to the longitudinal direction of the extension for the main structure.

[0040] In practice, since such a strut is intended to be fastened under the wing of the aircraft, the inclination of the main rib can correspond to the sweep of the aircraft wing, or at least to the angle formed by the structural part of the wing to which it is fixed (typically the wing spars) with respect to the fuselage of the aircraft, such that the assembled strut extends parallel to the fuselage.

[0041] An interface for fastening to aircraft 6, the interface being located at the end of the rear 9 of the main structure, and... Figure 1 The interface of the embodiment differs in that it is in the form of a plate for integration into the aircraft structure.

[0042] Figure 3 The main structure 1 of the support column according to an embodiment of the present invention is shown, wherein the embodiment is in Figure 2 The optimization of the main structure presented in the document. Figure 3 In the diagram, the main structure 1 is shown as being mounted on the aircraft structure, and it is partially shown.

[0043] In this embodiment, the front portion 8 of the main structure 1 extending to the main rib 10 has a similar shape to... Figure 2 The front part of the main structure has the same configuration as the 8.

[0044] Specifically, the main rib 10 has an extension 11 forming a plane for fixing to the aircraft structure. More precisely, the extension 11 is fastened to the wing spars 12.

[0045] In this invention, the main structure of the box is limited to its front part 8. The rear part 9 is composed of a set of connecting rods 13 and 14.

[0046] Figure 4 Showing with Figure 3 The same device, viewed from another perspective, provides a better view of the composition of the rear section 9 according to the invention. The wing 15 of the aircraft is partially shown. In the example embodiment shown here, the rear section 9 is generally composed of four connecting rods: two lower connecting rods 13 and two upper connecting rods 14.

[0047] The term connecting rod in this case corresponds to a straight connecting part, which is suitable for absorbing traction / compression forces.

[0048] Each connecting rod 13, 14 is coupled to the front portion 8 of the main structure via a first end 16 and to the aircraft structure via a second end 17. The coupling of connecting rods 13, 14 to the aircraft structure is achieved in this case via an interface including a coupling plate 18. The coupling plate allows coupling to the surface of the structural element at the lower surface of the wing 15. Each second end 17 is coupled to the aircraft structure via a joint independent of the joints of the other connecting rods. Thus, each connecting rod 13, 14 is coupled to the aircraft at a different coupling point via separate fastening interfaces.

[0049] It is possible Figure 5 The distribution of the connection points of connecting rods 13 and 14 on the lower surface of wing 15 can be seen. Figure 5 Will Figure 3 and 4 The device is shown as a "top" view, where the upper longitudinal member 3 is seen from the front.

[0050] Due to the inclination of the main rib 10 with respect to the transverse direction T at an angle α, the lower connecting rod 13 and the upper connecting rod 14 have substantially the same length, and the connecting rods are joined to the aircraft structure at four longitudinally distributed points. This allows for a good distribution of forces transmitted to the structure.

[0051] Specifically, the upper connecting rod 14 can have an extremely horizontal orientation, that is, substantially parallel to the main shaft extending from the main structure, so as to absorb forces oriented in the direction of the engine shaft of the power unit coupled to the main structure. The lower connecting rod is primarily used to absorb torques caused by vertical forces applied to the main structure.

[0052] In addition to its structural function, the main rib 10 can also function to close the end of the front part 8.

[0053] In reference Figures 3 to 5 In the detailed embodiment, each connecting rod generally consists of two strips, namely two flat strips. This configuration specifically makes it possible to form a yoke by providing concentric holes in each strip at the first end 16 and / or the second end 17 of the connecting rod, allowing for hinged joints with the front part 8 of the main structure and / or the aircraft structure (or an interface for joining to the aircraft structure), respectively.

[0054] In practice, each connecting rod 13, 14 is advantageously joined at each end by a hinged joint or a ball joint. This ensures that the connecting rods operate under traction / compression and limits residual forces in the connecting rods without mechanical stress from the power unit.

[0055] Apart from Figures 3 to 5 In addition to the two flat strips presented in the figure, the connecting rods 13 and 14 used in this invention may have Figure 6 The various alternative configurations presented in the document. More precisely, Figure 6 Various connecting rod cross-sections that can be used in this invention are shown. Therefore, each connecting rod can, for example, be based on... Figure 6 The cross-section presented from left to right is formed by two flat strips, a single flat strip, a strip with a cross-shaped cross-section, or a tube with a rectangular (e.g., square), circular (or elliptical), or triangular cross-section.

[0056] Based on the joints formed at the first end 16 and the second end 17, the connecting rod may have [specific features] throughout its entire length or for most of its length, and for example, for most of its length excluding the ends 16 and 17. Figure 6 One of the cross sections shown in the figure is used to form the joint.

[0057] Each connecting rod can also have a different cross-section. For example, the lower connecting rod can have the same cross-section as the upper connecting rod, but different from the cross-section of the upper connecting rod. In particular, the lower connecting rod 13 can have a circular cross-section to provide better equipment stability. Therefore, in an advantageous embodiment, the upper connecting rod 14 is flat, while the lower connecting rod is generally made of tubular material and preferably has a circular cross-section (circular).

[0058] Figure 7 The joint between the front part 8 and the rear part 9 of the main structure is shown. Figures 3 to 5 Detailed view of the equipment. Main rib 10 and the main structural housing (i.e., typically composed of...) Figure 2 The geometry of the main structure (defined by the box) is defined by the intersection of the quadrilaterals formed at the first ends 16 of the connecting rods 13 and 14. In the example shown in this case, each of the transverse panels 5 has at least one longitudinal extension 19 extending beyond the main rib 10. At the upper part (on the side of the upper longitudinal member 3) and at the lower part (on the side of the lower longitudinal member 4), the extension 19 includes an eyelet 20 that allows the yoke pin 21 to pass through in order to form a hinged joint.

[0059] For example, Figure 7 As shown, at the second end 17 of each connecting rod, a yoke-type hinge joint, similar to the joint formed with the front, can be formed with an interface including the plate 18.

[0060] Figure 7 The embodiment is based on a pre-existing geometry derived from the prior art for the main structure of the aircraft power plant support strut. Figure 8 The embodiment shown corresponds to the geometric optimization of the main structure allowed by using the rear portion 9, which is composed of a connecting rod, according to the invention. For example... Figure 7 As shown, the main rib 10 is tilted at an angle α, resulting in a transverse panel 5 on one side of the front portion 8, which has a substantially triangular or quadrilateral shape, and on the other side ( Figure 7 The panel (shown in the foreground) has a complex shape. The upper longitudinal member 3 also has a cross blade that increases its manufacturing cost.

[0061] Figure 8 The embodiment shown is a variation that optimizes the points stated above. Specifically, the upper longitudinal member 3 has a planar shape extending to the main rib 10. Correspondingly, the two transverse panels 5 have simple shapes, such as trapezoids or triangles. Compared to Figure 7 In this embodiment, production costs are thus reduced. Furthermore, mechanical properties are improved. This is due to the... Figure 7 This improvement is achieved by potentially raising the upper connecting rod 14 on the modified side of the main structure compared to the embodiment, resulting in moving the upper connecting rod 14 away from the lower connecting rod 13. In practice, Figure 8 In this embodiment, the upper connecting rod 14 in the foreground can be located at the same level as the upper connecting rod on the other side, or above the latter (i.e., moved further away from the lower connecting rod 13). The spacing between the connecting rods allows for better absorption of forces within the connecting rods. In particular, the more the upper and lower connecting rods are spaced apart from each other, the smaller the overturning moment applied to the front 8 (e.g., the vertical force applied at the end of the front) will generate a substantial traction / compression force in the lower connecting rod.

[0062] The invention described above allows for a significant simplification of the main structure used to support the aircraft's power unit. This simplification also results in a reduction in the length of certain components (longitudinal members, transverse panels), allowing for a substantial reduction in manufacturing costs. Although specific embodiments from the prior art are used for illustration (in this particular case, see reference...), Figure 2 (The main structure described), however, the invention can be applied using a main structure including any type of front portion 8, particularly with reference to the main structure described above. Figure 1 The main structure is similar to that described.

[0063] Furthermore, various joints that can be used at the end of the connecting rod can be produced in various ways known further from the prior art.

[0064] In addition to reduced production costs and simplified implementation, the rear section offers other advantages or opportunities through the formation of a set of connecting rods. The upper longitudinal members can be simplified by giving it a flat shape. The central rib can have a secondary function of closing the box formed by the front section. The rear section is also less constrained by the issue of conforming to aerodynamic shapes, and its integration into the secondary strut structure that generally forms an aerodynamic fairing is simplified.

Claims

1. The main structure (1) for supporting the aircraft power plant, including a front part (8) intended to be integrated into the aircraft power plant and a rear part (9) intended to be integrated into the aircraft structure. The front part (8) is formed by a box including an upper longitudinal member, a lower longitudinal member and a transverse panel. The main structure includes a main rib (10) located at the interface between the front portion (8) and the rear portion (9); wherein the main rib (10) is extended beyond the upper longitudinal member (3) of the front portion of the main structure to form a plane for fastening to the aircraft structure; characterized in that, The rear portion (9) is formed by a set of connecting rods (13, 14), each connecting rod (13, 14) including a first end (16) and a second end (17), the first end (16) of each connecting rod (13, 14) being coupled to the front portion (8) of the main structure, and the second end (17) of each connecting rod (13, 14) being coupled to a separation interface for fastening to the aircraft structure, and wherein there are four connecting rods (13, 14), the intersection of the main rib (10) and the front portion (8) of the main structure forming a quadrilateral including four corners, and a connecting rod (13, 14) being coupled to the front portion substantially at each of the corners.

2. The main structure according to claim 1, wherein each connecting rod (13, 14) is connected to the front (8) at the separated joint using a hinged or ball joint.

3. The main structure according to claim 1 or claim 2, wherein each connecting rod (13, 14) is formed by a flat strip or by two parallel flat strips or by a tube having a triangular, square, rectangular or circular cross section for at least a majority of its length.

4. The main structure according to claim 1 or claim 2, wherein the set of connecting rods (13, 14) includes a so-called lower connecting rod (13) and a so-called upper connecting rod (14), and wherein the lower connecting rod (13) and the upper connecting rod have different cross sections for at least a majority of their lengths.

5. The main structure according to claim 1 or claim 2, wherein the set of connecting rods (13, 14) includes a so-called lower connecting rod (13) and a so-called upper connecting rod (14), and wherein the lower connecting rod (13) has a length different from that of the upper connecting rod (14).

6. The main structure according to claim 1, wherein the intersection of the main rib (10) with the plane parallel to the lower longitudinal member is inclined with respect to the transverse direction, the transverse direction being orthogonal to the longitudinal direction in the plane, the longitudinal direction corresponding to the extension direction of the front portion (8) of the main structure.

7. The main structure according to claim 1 or claim 2, wherein each of the transverse panels (5) of the front portion (8) includes an extension (19) extending beyond the main rib, each extension including at least one eyelet (20) for fastening the connecting rod.

8. The main structure according to claim 1 or claim 2, wherein each interface for fastening to the second end of the connecting rod of the aircraft structure comprises a hinged or ball joint with the second end (17) of the connecting rod (13, 14), and a plate for fastening (18) to the aircraft structure.

9. An aircraft comprising at least one wing (15) and at least one power unit mounted beneath said wing (15), characterized in that, The power unit is attached to the wing by means of a load-bearing strut comprising the main structure according to any one of the preceding claims.

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