A lightweight main body fuselage skeleton structure applied to a tilt-rotor aircraft

Abstract

The application relates to a light main body skeleton structure applied to a tilt-rotor aircraft, which comprises a chassis assembly, a frame assembly and a tail frame, the chassis assembly is provided with oppositely arranged front and rear ends, and the tail frame is located at the rear end; the frame assembly comprises a first truss, a second truss, a third truss and a fourth truss, and the first truss, the second truss, the third truss and the fourth truss are sequentially and fixedly arranged on the chassis assembly from the front end to the rear end; the frame assembly further comprises truss beams, the truss beams are sequentially connected with the first truss, the second truss, the third truss and the fourth truss, so that the frame assembly forms a streamlined shape, has the effect of simplifying the body structure, and facilitates the aircraft to realize long-range high-speed flight.

Description

Technical Field

[0001] This invention relates to the field of aircraft design technology, and in particular to a lightweight main fuselage frame structure for tiltrotor aircraft. Background Technology

[0002] Tiltrotor aircraft, combining the advantages of helicopters and fixed-wing aircraft, have been increasingly widely used in recent years. They have particularly broad application value in military-civilian joint construction fields such as emergency rescue, cargo transportation, forest protection, power line inspection, and combat missions.

[0003] Most existing tiltrotor aircraft consist of arms extending outwards from the fuselage, with motors and propellers mounted on these arms to drive the aircraft's flight. Tilting is achieved by adjusting the propeller angle during flight. This design places the primary stress points at the junction of the arms and fuselage, requiring reinforcement of these areas during design, which increases the weight of the fuselage and arms and negatively impacts flight performance. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to overcome the defects in the prior art, thereby providing a lightweight main fuselage frame structure for tiltrotor aircraft.

[0005] To achieve the above objectives, the present invention adopts the following technical solution:

[0006] A lightweight main fuselage frame structure for a tiltrotor aircraft includes: a base frame assembly, a frame assembly, and a tail fin assembly. The base frame assembly has a front end and a rear end disposed opposite to each other, and the tail fin assembly is located at the rear end. The frame assembly includes a first truss, a second truss, a third truss, and a fourth truss, and the first truss, the second truss, the third truss, and the fourth truss are sequentially fixed to the base frame assembly at intervals from the front end to the rear end. The frame assembly also includes trusses that sequentially connect the first truss, the second truss, the third truss, and the fourth truss to make the frame assembly streamlined.

[0007] Preferably, the frame assembly further includes a plurality of web strips; the web strips are located between the first truss, the second truss, the third truss, the fourth truss, the truss beam and the underframe assembly, so that the first truss, the second truss, the third truss, the fourth truss, the truss beam and the underframe assembly are mutually tractioned and form a cabin.

[0008] Preferably, the line connecting the connection point of the first truss and the base frame assembly forms a first region with the first truss; the line connecting the connection point of the second truss and the base frame assembly forms a second region with the second truss; the line connecting the connection point of the third truss and the base frame assembly forms a third region with the third truss; and the line connecting the connection point of the fourth truss and the base frame assembly forms a fourth region with the fourth truss; the ratio of the areas of the first region, the second region, the third region, and the fourth region is 1:2.85:2.25:1.75.

[0009] Preferably, the first truss and the third truss are configured as arc-shaped rods; the second truss and the fourth truss are configured as closed loops.

[0010] Preferably, the underframe assembly includes a base beam and at least two base trusses symmetrically arranged at both ends of the base beam; the base trusses include a first base truss, a second base truss, and a third base truss arranged sequentially from the front end to the rear end; the underframe assembly further includes a first duct ring located between the first base truss and the second base truss, and a second duct ring located between the second base truss and the third base truss; the angle between the plane containing the central axes of the first duct ring and the second duct ring and the plane containing the first base truss ranges from 3° to 7°.

[0011] Preferably, the second bottom truss includes a recessed portion and an upper extension portion; the recessed portion is fixedly connected to the first duct ring and extends from the first duct ring away from the truss to the upper extension portion, and is fixedly connected to one end of the upper extension portion, and the other end of the upper extension portion is fixedly connected to the second duct ring.

[0012] Preferably, the ends of the two first trusses away from the first duct ring are connected by an arc segment to form a guide end whose width gradually increases from the front end to the rear end.

[0013] Preferably, the ratio of the distance from the first duct ring to the connection point of the two first bottom trusses to the distance from the second duct ring to the connection point of the two first bottom trusses is 1:3.

[0014] Preferably, the system further includes wing limiting rods symmetrically arranged about the bottom truss beam. The wing limiting rods include a first wing limiting rod and a second wing limiting rod. The first wing limiting rod is located on the side of the second truss away from the front end, so that a front wing mounting area is formed between the first wing limiting rod and the second truss. The second wing limiting rod is located on the side of the third truss away from the rear end, so that a rear wing mounting area is formed between the second wing limiting rod and the third truss.

[0015] Preferably, the first wing limiting rod, the second truss, the second wing limiting rod, and the third truss are all provided with wing mounting rings; the central axis of the wing mounting ring is parallel to the arrangement direction of the second truss and the third truss.

[0016] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0017] The lightweight main fuselage frame structure for tiltrotor aircraft provided in the above technical solution forms the main frame of the fuselage by sequentially arranging a first truss, a second truss, a third truss, and a fourth truss at intervals from the front end to the rear end of the base frame assembly. This simplifies the fuselage structure. Furthermore, the first, second, third, and fourth trusses are connected by truss beams, enabling mutual traction between them and increasing the stress balance and stability of the entire fuselage. In addition, the frame assembly formed by the connection of the first, second, third, and fourth trusses and truss beams has a streamlined distribution, which helps reduce air resistance during flight and facilitates long-range, high-speed flight. Attached Figure Description

[0018] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0019] Figure 1 A schematic diagram of the fuselage frame structure provided by the present invention.

[0020] Figure 2 for Figure 1 A top-down view.

[0021] Figure 3 for Figure 1 A diagram showing the view from the right.

[0022] Explanation of reference numerals in the attached figures:

[0023] 1. Underframe assembly; 10. Underframe crossbeam; 11. First underframe truss; 111. Arc segment; 12. Second underframe truss; 121. Lower section; 122. Upper extension; 13. Third underframe truss; 14. First duct ring; 15. Second duct ring; 2. Frame assembly; 21. First truss; 22. Second truss; 23. Third truss; 24. Fourth truss; 25. Truss beam; 26. Web slats; 3. Tail wing frame; 4. Cabin; 5. Wing limiting rod; 51. First wing limiting rod; 52. Second wing limiting rod; 6. Wing mounting ring; 101. First area; 102. Second area; 103. Third area; 104. Fourth area. Detailed Implementation

[0024] The technical solution of the present invention will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0025] In the description of this invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing the invention and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0026] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0027] See Figures 1 to 3 This invention provides a lightweight main fuselage frame structure for a tiltrotor aircraft, comprising: a base frame assembly 1, a frame assembly 2, and a tail fin assembly 3. Specifically, the base frame assembly 1 has a front end and a rear end that are arranged opposite to each other, and the tail fin assembly 3 is located at the rear end. The base frame assembly 1, the frame assembly 2, and the tail fin assembly 3 are symmetrically distributed, and their symmetry plane is a vertical plane extending from the front end to the rear end and perpendicular to a local plane of the base frame assembly 1.

[0028] See Figure 1 The frame assembly 2 includes a first truss 21, a second truss 22, a third truss 23 and a fourth truss 24, and the first truss 21, the second truss 22, the third truss 23 and the fourth truss 24 are fixed to the base frame assembly 1 at intervals from the front end to the rear end to form the main frame of the fuselage, thereby simplifying the fuselage structure.

[0029] The frame assembly 2 also includes trusses 25, which sequentially connect the first truss 21, the second truss 22, the third truss 23, and the fourth truss 24 to form a streamlined shape. The first truss 21, the second truss 22, the third truss 23, and the fourth truss 24 are connected by trusses 25, enabling mutual traction among them, increasing the force balance and stability of the entire fuselage. In addition, the streamlined distribution of the frame assembly 2 formed by the first truss 21, the second truss 22, the third truss 23, the fourth truss 24, and trusses 25 facilitates the reduction of air resistance during flight, enabling the aircraft to achieve long-range, high-speed flight.

[0030] Furthermore, the frame assembly 2 also includes several web strips 26; the web strips 26 are located between the first truss 21, the second truss 22, the third truss 23, the fourth truss 24, the truss beams 25, and the underframe assembly 1, so that the first truss 21, the second truss 22, the third truss 23, the fourth truss 24, the truss beams 25, and the underframe assembly 1 are mutually tractioned and form the cabin 4. Specifically, see [link to documentation]. Figure 1 The belly strips 26 are disposed on both sides of the cabin 4, thereby forming the side walls of the cabin 4. The arrangement and number of belly strips 26 can be set according to the stress on the fuselage frame. In this embodiment, the belly strips 26 may include rods that are inclined and vertically arranged, so that the belly strips 26 can pull on the first truss 21, the second truss 22, the third truss 23, the fourth truss 24, the truss beam 25 and the underframe assembly 1, so that the stress on the entire fuselage frame is more even.

[0031] See Figure 1To make the entire fuselage frame more stable and more stable during flight, in this embodiment, the line connecting the connection point of the first truss 21 and the base frame assembly 1 forms a first region 101 with the first truss 21; the line connecting the connection point of the second truss 22 and the base frame assembly 1 forms a second region 102 with the second truss 22; the line connecting the connection point of the third truss 23 and the base frame assembly 1 forms a third region 103 with the third truss 23; and the line connecting the connection point of the fourth truss 24 and the base frame assembly 1 forms a fourth region 104 with the fourth truss 24. The area ratio of the first region 101, the second region 102, the third region 103, and the fourth region 104 is 1:2.85:2.25:1.75. The first truss 21 and the third truss 23 are configured as arc-shaped rod structures; the second truss 22 and the fourth truss 24 are configured as closed rings. The second truss 22 can be elliptical in shape, and the fourth truss 24 can be configured as a gate-type ring truss. Of course, in other embodiments, the first truss 21, the second truss 22, the third truss 23 and the fourth truss 24 can all be configured as closed loops. In this case, the first region 101, the second region 102, the third region 103 and the fourth region 104 can be configured as the region enclosed by the first truss 21, the second truss 22, the third truss 23 and the fourth truss 24.

[0032] See Figure 1 , Figure 2 The underframe assembly 1 includes a bottom beam 10 and two bottom trusses symmetrically arranged at both ends of the bottom beam 10. The bottom trusses include a first bottom truss 11, a second bottom truss 12 and a third bottom truss 13 arranged sequentially from the front end to the rear end. The underframe assembly 1 also includes a first duct ring 14 located between the first bottom truss 11 and the second bottom truss 12, and a second duct ring 15 located between the second bottom truss 12 and the third bottom truss 13.

[0033] See Figure 1 The ends of the two first bottom trusses 11 that are away from the first duct ring 14 are connected by an arc segment 111 to form a guide end with a gradually increasing width from the front end to the rear end, thereby facilitating the reduction of wind resistance during the flight of the aircraft.

[0034] See Figure 3Since the first ducted ring 14 and the second ducted ring 15 need to install the aircraft's power components, in order to enable the power components to drive the entire aircraft in a balanced and stable manner, in this embodiment, the angle A between the plane containing the central axis of the first ducted ring 14 and the second ducted ring 15 and the plane containing the first under-truss 11 (parallel to the horizontal plane) can be set to 3°, 5° or 7°, and both the first ducted ring 14 and the second ducted ring 15 can be fixedly connected to the truss beam 25 by a vertically set web strip 26; furthermore, in order to make the entire fuselage frame bear force evenly, the ratio of the distance L1 from the first ducted ring 14 to the connection point of the two first under-truss 11 to the distance L2 from the second ducted ring 15 to the connection point of the two first under-truss 11 is 1:3.

[0035] Furthermore, in order to balance the forces on the entire fuselage and facilitate stable flight of the aircraft, in this embodiment, the second under-truss 12 includes a recessed portion 121 and an upper extension portion 122; the recessed portion 121 is fixedly connected to the first duct ring 14 and extends from the first duct ring 14 to the side away from the truss 25 to the upper extension portion 122, and is fixedly connected to one end of the upper extension portion 122, and the other end of the upper extension portion 122 is fixedly connected to the second duct ring 15; the angle B between the recessed portion 121 and the plane where the first under-truss 11 is located can be set to 17.5°.

[0036] See Figure 1 , Figure 2 To facilitate wing installation and vertical movement, the fuselage frame also includes wing limiting rods 5 symmetrically arranged about the bottom crossbeam 10. The wing limiting rods 5 include a first wing limiting rod 51 and a second wing limiting rod 52. The first wing limiting rod 51 is located on the side of the second truss 22 furthest from the front end, and both the first wing limiting rod 51 and the second truss 22 protrude towards the end furthest from the bottom crossbeam 10, forming an arc-shaped protrusion. This creates a forward wing mounting area between the first wing limiting rod 51 and the second truss 22 for installing the front wing. Similarly, the second wing limiting rod 52 is located on the side of the third truss 23 furthest from the rear end, and both the second wing limiting rod 52 and the third truss 23 protrude towards the end furthest from the bottom crossbeam 10, forming an arc-shaped protrusion. This creates a rear wing mounting area between the second wing limiting rod 52 and the third truss 23 for installing the rear wing.

[0037] For ease of installation, in this embodiment, wing mounting rings 6 are provided on the first wing limiting rod 51, the second truss 22, the second wing limiting rod 52, and the third truss 23; the central axis of the wing mounting ring 6 is parallel to the arrangement direction of the second truss 22 and the third truss 23.

[0038] The above embodiments are merely preferred embodiments of the present invention and should not be construed as limiting the scope of protection of the present invention. Any non-substantial changes and substitutions made by those skilled in the art based on the present invention shall fall within the scope of protection claimed by the present invention.

Claims

1. A lightweight main fuselage frame structure for a tiltrotor aircraft, comprising: The underframe assembly (1), the frame assembly (2), and the tail fin assembly (3) are characterized in that, The underframe assembly (1) has a front end and a rear end that are arranged opposite to each other, and the tail fin (3) is located at the rear end; The frame assembly (2) includes a first truss (21), a second truss (22), a third truss (23) and a fourth truss (24), and the first truss (21), the second truss (22), the third truss (23) and the fourth truss (24) are fixed to the base frame assembly (1) at intervals from the front end to the rear end; The frame assembly (2) further includes a truss beam (25) which connects the first truss (21), the second truss (22), the third truss (23) and the fourth truss (24) in sequence, so that the frame assembly (2) forms a streamlined shape; The base frame assembly (1) includes a base beam (10) and at least two base trusses symmetrically arranged at both ends of the base beam (10); The base truss includes a first base truss (11), a second base truss (12), and a third base truss (13) arranged sequentially from the front end to the rear end. The underframe assembly (1) further includes a first duct ring (14) located between the first underframe truss (11) and the second underframe truss (12), and a second duct ring (15) located between the second underframe truss (12) and the third underframe truss (13). The angle between the plane containing the central axis of the first culvert ring (14) and the plane containing the first truss (11) is 3° to 7°. It also includes wing limiting rods (5) symmetrically arranged about the bottom crossbeam (10), the wing limiting rods (5) including a first wing limiting rod (51) and a second wing limiting rod (52); The first wing limiting rod (51) is located on the side of the second truss (22) away from the front end, so that a front wing mounting area is formed between the first wing limiting rod (51) and the second truss (22); The second wing limiting rod (52) is located on the side of the third truss (23) away from the rear end, so that a rear wing mounting area is formed between the second wing limiting rod (52) and the third truss (23).

2. The lightweight main fuselage frame structure for a tiltrotor aircraft according to claim 1, characterized in that, The frame component (2) also includes several belly strips (26); The web strip (26) is located between the first truss (21), the second truss (22), the third truss (23), the fourth truss (24), the truss beam (25) and the underframe assembly (1) so that the first truss (21), the second truss (22), the third truss (23), the fourth truss (24), the truss beam (25) and the underframe assembly (1) pull each other together and form the cabin (4).

3. The lightweight main fuselage frame structure for a tiltrotor aircraft according to claim 1, characterized in that, The line connecting the connection point of the first truss (21) and the base frame assembly (1) forms a first region (101) with the first truss (21); the line connecting the connection point of the second truss (22) and the base frame assembly (1) forms a second region (102) with the second truss (22); the line connecting the connection point of the third truss (23) and the base frame assembly (1) forms a third region (103) with the third truss (23); and the line connecting the connection point of the fourth truss (24) and the base frame assembly (1) forms a fourth region (104) with the fourth truss (24). The area ratio of the first region (101), the second region (102), the third region (103), and the fourth region (104) is 1:2.85:2.25:1.

75.

4. A lightweight main fuselage frame structure for a tiltrotor aircraft according to claim 1 or 3, characterized in that, The first truss (21) and the third truss (23) are configured as arc rods; the second truss (22) and the fourth truss (24) are configured as closed rings.

5. The lightweight main fuselage frame structure for a tiltrotor aircraft according to claim 1, characterized in that, The second bottom truss (12) includes a recessed portion (121) and an upper extension portion (122). The recessed portion (121) is fixedly connected to the first duct ring (14) and extends from the first duct ring (14) away from the truss (25) to the upper extension portion (122), and is fixedly connected to one end of the upper extension portion (122), while the other end of the upper extension portion (122) is fixedly connected to the second duct ring (15).

6. The lightweight main fuselage frame structure for a tiltrotor aircraft according to claim 1, characterized in that, The ends of the two first truss beams (11) away from the first duct ring (14) are connected by an arc segment (111) to form a guide end with a gradually increasing width from the front end to the rear end.

7. A lightweight main fuselage frame structure for a tiltrotor aircraft according to claim 6, characterized in that, The ratio of the distance from the first duct ring (14) to the connection point of the two first bottom trusses (11) to the distance from the second duct ring (15) to the connection point of the two first bottom trusses (11) is 1:

3.

8. The lightweight main fuselage frame structure for a tiltrotor aircraft according to claim 1, characterized in that, The first wing limiting rod (51), the second truss (22), the second wing limiting rod (52) and the third truss (23) are all provided with wing mounting rings (6); The central axis of the wing mounting ring (6) is parallel to the arrangement direction of the second truss (22) and the third truss (23).

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