Aircraft tail structure

Abstract

An aircraft tail structure equipped with an electric ducted propulsion device, comprising a tail body, a tail wing mounted on the tail body, and the electric ducted propulsion device wherein the electric ducted propulsion device has: a fan body arranged to extend from the tail body, comprising a duct center cone and a plurality of fan blades arranged around the duct center cone. The motor is connected to the ducted center cone through a transmission mechanism. The machine tail body shrinks backwards in the longitudinal direction so that a shrinking part can be formed at the tail end of the machine tail body, the motor is arranged to be spaced from the fan body by a first distance in the longitudinal direction so that the motor can be located on the front side of the shrinking part, and the fan body is located on the rear side of the shrinking part and fixed into the machine tail body through the motor fixing device. According to the aircraft tail structure, mutual interference between the size of the motor and the size of the duct center cone is eliminated, and the structure and aerodynamic performance of the electric duct propelling device can be optimized while high-power operation is guaranteed.

Description

Technical Field

[0001] The utility model relates to the field of aircraft propulsion system design, and in particular to an aircraft tail structure with an electric ducted propulsion device, and an aircraft with the aircraft tail structure. Background Art

[0002] Compared with traditional fuel-driven aircraft, electric propulsion aircraft have incomparable advantages in reducing carbon emissions. At the same time, compared with electric propellers, electric ducted propulsion devices can adapt to a wider speed range by adjusting the tail cone position, stator blade angle and other means, making the aircraft's high and low speed aerodynamic performance even better.

[0003] Boundary layer extraction (BLI) propulsion technology has also received some attention in recent years. NASA has tried to add a turbofan engine to the tail of the fuselage in its research on the truss-supported wing scheme, and use the tail-thrust turbofan engine to extract the fuselage boundary layer to achieve the purpose of drag reduction during high-speed cruising. However, using a turbofan engine that burns fossil fuels as tail thrust will inevitably produce carbon emissions. Therefore, to achieve the goal of complete emission reduction, an electric ducted propulsion device can be selected as the tail thrust device.

[0004] At present, traditional electric ducted propulsion devices generally choose to place the power motor in the duct center cone. Therefore, the diameter and length of the duct center cone interact with the power motor. Because the duct center cone must be sized to accommodate the power motor, and the size of the power motor is affected by the power required by the electric ducted propulsion device. If the power required by the electric ducted propulsion device is large, the size of the motor must be large, so a larger duct center cone must be used. However, an overly large duct center cone will limit the intake area of ​​the duct air inlet. In order to ensure the intake efficiency, it is necessary to increase the overall size of the fan body of the electric duct. This brings extra weight and causes aerodynamic losses.

[0005] From the perspective of the tail structure, the integration of the electric ducted propulsion device at the tail of the fuselage requires the fuselage to be narrowed at the ducted air inlet to maximize the drag reduction effect of boundary layer suction. However, a too narrow tail of the fuselage makes it difficult to ensure sufficient structural strength and rigidity.

[0006] From the perspective of maintainability, the current design of the electric duct propulsion device, which places the power motor in the center cone of the duct, requires that the power motor be repaired in the narrow space of the duct, or even the power motor must be removed for a comprehensive repair, which makes it difficult to maintain the motor.

[0007] Therefore, there is a need to provide an improved aircraft tail structure that can solve the above-mentioned problems and defects in the prior art. Utility Model Content

[0008] The utility model aims to provide an aircraft tail structure with an electric ducted propulsion device, wherein the motor is separated from the duct center cone and fixed inside the fuselage, so that the electric ducted propulsion device can be designed with optimal aerodynamic and structural settings.

[0009] According to the utility model, an aircraft tail structure equipped with an electric ducted propulsion device is proposed, the aircraft tail structure includes a tail body, a tail wing installed on the tail body, and an electric ducted propulsion device, wherein the electric ducted propulsion device has: a fan body, the fan body is arranged to continue from the tail body, including a duct center cone and a plurality of fan blades arranged around the duct center cone; a motor, the motor is connected to the duct center cone by means of a transmission mechanism. The tail body shrinks rearward along the longitudinal direction to form a contraction portion at the tail end of the tail body, the motor is arranged to be spaced a first distance from the fan body along the longitudinal direction so that the motor is located at the front side of the contraction portion, and the fan body is located at the rear side of the contraction portion, and is fixed to the inside of the tail body by a motor fixing device. Such an arrangement makes the sizes of the motor and the duct center cone no longer interfere with each other, thereby improving the design freedom of the aircraft tail structure.

[0010] According to another aspect of the present disclosure, the electric ducted propulsion device also includes a suspension structure, which includes: a base barrel, which includes a hollow cylinder and is fixed around the duct center cone by means of a plurality of ribs; and a plurality of hangers, which are circumferentially distributed on the base barrel and extend in the longitudinal direction.

[0011] According to still another aspect of the present disclosure, a plurality of pylons are installed to be buried in the tail wing.

[0012] According to yet another aspect of the present disclosure, a radial dimension of the motor is greater than a radial dimension of the central cone of the duct.

[0013] According to another aspect of the present disclosure, the first distance is greater than the length of the hanger in the longitudinal direction. However, it is also conceivable that the first distance is less than the length of the hanger in the longitudinal direction.

[0014] According to yet another aspect of the present disclosure, the hanger is pivotably connected to the base barrel via a pivot shaft.

[0015] According to yet another aspect of the present disclosure, a hanger includes a frame structure having a plurality of reinforcing ribs.

[0016] According to yet another aspect of the present disclosure, a motor fixing device includes a bracket structure fixed to the motor and an inner wall surface of a tail body at the same time.

[0017] According to yet another aspect of the present disclosure, the electric ducted propulsion device further includes a fan duct fairing, which is arranged to surround the base barrel and is integrated with the tail wing.

[0018] According to another aspect of the present disclosure, a tail wing of an aircraft tail structure includes two outward-inclined vertical tails and a ventral fin, and the outward-inclined vertical tails and the ventral fin are distributed in a Y shape around a tail body.

[0019] The tail structure of the aircraft of the utility model adopts a split design, and the motor is arranged to be away from the fan body including the duct center cone and fixed to the inside of the tail body. Since the motor is no longer arranged in the duct center cone, the sizes of the two are no longer affected by each other, so that a large-sized high-power motor and a small-sized high-efficiency ventilation duct center cone can be arranged at the same time, that is, the electric duct propulsion device can be designed with the optimal structural parameters and aerodynamic performance parameters. In addition, since the electric duct propulsion device of the utility model adopts an integrated design with the aircraft, its hanger is buried in the tail wing of the aircraft, and a part of the duct fairing is also combined with the tail wing, even when the tail body is narrowed, the electric duct propulsion device can be firmly fixed by means of the extended shape of the aircraft tail wing, thereby ensuring the strength of the fuselage structure. Finally, since the motor of the utility model is arranged inside the tail body, the inside of the fuselage can be reached by opening an inspection port in the fuselage, so that the motor can be inspected, which significantly improves the maintainability. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] For a more complete understanding of the present disclosure, reference may be made to the following description of exemplary embodiments considered in conjunction with the accompanying drawings. The accompanying drawings are not intended to limit the present disclosure to the specific embodiments depicted therein and are not necessarily to scale. In the drawings:

[0021] Figure 1 is a three-dimensional diagram of an electric ducted propulsion device according to a preferred embodiment of the utility model, wherein the ducted fairing is removed;

[0022] Figure 2 yes Figure 1 An exploded view of the electric ducted propulsion unit;

[0023] Figure 3 yes Figure 1 Another exploded view of the electric ducted propulsion device; and

[0024] Figure 4 Yes Figure 1 The tail structure of an aircraft with an electric ducted propulsion device, wherein the motor of the electric ducted propulsion device is particularly shown.

[0025] Reference numerals list

[0026] 100 Aircraft tail structure

[0027] 1 Tail body

[0028] 101 inner wall

[0029] 110 Contraction

[0030] 2 tail wing

[0031] 201 outward inclined vertical tail

[0032] 202 Pelvic fin

[0033] 3Electric ducted propulsion device

[0034] 301 Ducted Fairing

[0035] 302 fan body

[0036] 321 Duct Center Cone

[0037] 322 fan blades

[0038] 323 Leaf Root

[0039] 324 Roulette

[0040] 325 holed tab

[0041] 303 motor

[0042] 304 transmission mechanism

[0043] 341 drive shaft

[0044] 411 First End

[0045] 412 Second end

[0046] 41 / 41' through hole

[0047] 342 first adapter

[0048] 343 Second adapter

[0049] 34 / 34' middle section

[0050] 35 / 35' end section

[0051] 305 hanging structure

[0052] 351 base tube

[0053] 511 outer surface of the base tube

[0054] 512 ribs

[0055] 352 hanger

[0056] 522 First End

[0057] 221 mounting holes

[0058] 523 Second End

[0059] 524 reinforcement ribs

[0060] 353 pivot shaft

[0061] 354 Bump

[0062] 306 motor fixing device

[0063] l1 first distance

[0064] l2 Length of the hanger

[0065] X vertical direction

[0066] Y horizontal direction

[0067] Z vertical direction DETAILED DESCRIPTION

[0068] The following description of the present invention for specific embodiments refers to the accompanying drawings, which show specific embodiments in which the present invention can be practiced. The embodiments are intended to fully describe the various aspects of the present invention in detail so that those skilled in the art can implement the present invention. Other embodiments may be utilized and may be changed without departing from the scope of the present invention. Therefore, the following description of specific embodiments should not be considered restrictive. The scope of the present invention is limited only by the appended claims and the full range of equivalents covered by the claims. The same reference numerals are used in all drawings and specific embodiments to refer to the same or similar parts.

[0069] In the following description, X denotes the longitudinal direction, which corresponds to the axis of the aircraft extending from the nose to the tail of the aircraft, i.e., along the longitudinal direction. Figure 4 As shown, the direction from the motor 303 toward the duct center cone 321; Y indicates the lateral direction perpendicular to the longitudinal direction. When the aircraft is on the ground (such as Figure 4 In the embodiment of the present invention, when the aircraft is in the position shown in the figure, it is horizontal; and Z denotes the vertical direction or vertical height direction when the aircraft is on the ground; these three directions X, Y and Z are mutually orthogonal. In addition, the directional terms such as "front" and "rear" are defined according to the directions X, Y, and Z; "circumferential" and "radial" are directional terms considered relative to the longitudinal direction X of the rotating parts.

[0070] Figure 4 The overall diagram shows an aircraft tail structure 100 having installed therein an electric ducted propulsion device 3 according to the present invention. Figures 1 to 3The assembly diagram and the exploded diagram of the electric ducted propulsion device 3 are shown respectively. As shown in the accompanying drawings, the aircraft tail structure 100 generally includes a tail body 1, a tail wing 2 mounted on the tail body 1, and an electric ducted propulsion device 3 including a ducted fairing 301. The tail body 1 shrinks rearward along the longitudinal direction X, thereby forming a shrinkage portion 110 at the tail end of the tail body 1; the tail wing 2 includes two outward-inclined vertical tails 201 extending laterally and a ventral fin 202 extending vertically, and the outward-inclined vertical tail 201 and the ventral fin 202 extend to the ducted fairing 301 respectively and are partially combined with the ducted fairing 301.

[0071] Figure 1 The assembly view of the electric ducted propulsion device 3 is shown, and the ducted fairing 301 is not shown in order to enable a clear view of its internal structure; Figure 2 and Figure 3 The various components constituting the electric ducted propulsion device 3 are shown from different angles. Figure 2 and Figure 3 As clearly shown, the electric ducted propulsion device 3 includes a fan body 302 having a ducted central cone 321 and a plurality of fan blades 322 arranged around the ducted central cone 321. Specifically, as Figure 2 As shown, a plurality of fan blades 322 are respectively fixed to a wheel disc 324 with their blade roots 323 and are circumferentially spaced from each other. The wheel disc 324 is rotatably connected to the duct center cone 321 to allow the fan blades 322 to rotate relative to the duct center cone 321. Preferably, the fan blades 322 are located in front of the duct center cone 321 along the longitudinal direction X. Figure 4 As shown, the fan body 302 is installed at the rear of the tail body 1 and continues from the tail body 1 , that is, extends along the longitudinal direction X continuously from the tail body 1 .

[0072] The electric ducted propulsion device 3 further comprises a motor 303, which is arranged in front of the fan body 302 along the longitudinal direction X and is spaced apart from the fan body 302 (especially the fan blades 322) by a first distance l1. Figure 4 As shown, the motor 303 is fixed inside the tail body 1 and connected to the duct center cone 321 by means of a transmission mechanism 304. Specifically, along the longitudinal direction X, the motor 303 is located at the front side of the contraction portion 110, and the fan body 302 is located at the rear side of the contraction portion 110. Figure 4As shown, the radial dimension of the motor 303 may be greater than the radial dimension of the duct center cone 321, that is, the diameter of the motor 303 is greater than the maximum diameter of the duct center cone 321; and / or the radial dimension of the motor 303 may be greater than the radial dimension of the contraction portion 110, for example, the diameter of the motor 303 is greater than the minimum diameter of the contraction portion 110. Preferably, the motor 303 is fixed in place in the tail body 1 by the motor fixing device 306. In this preferred embodiment, as Figure 4 As shown, the motor fixing device can be a bracket structure fixed to both the motor 303 and the inner wall surface 101 of the tail body 1; but it can also be conceived in an alternative embodiment that it includes a cage structure fixed to the inner wall surface 101 of the tail body 1 at one end and having a receiving cavity at the other end to accommodate the motor 303.

[0073] like Figures 1 to 3 As shown, in a preferred embodiment of the present invention, the transmission mechanism 304 includes a transmission shaft 341. In a preferred embodiment of the present invention, the first distance l1 is greater than the length l2 of the hanger 352 of the suspension structure 305 of the electric ducted propulsion device 3 along the longitudinal direction X. However, the present invention is not limited thereto, and the size of the first distance l1 depends on the size of the accommodation space of the tail body 1 that allows the motor 303 to be accommodated. If the accommodation space is small, the motor 303 needs to be positioned further forward along the longitudinal direction X to find a larger accommodation space that allows it to be placed in place, which causes the first distance l1 to be further increased; if the accommodation space is small, the motor 303 can be positioned closer to the fan body 302, that is, the first distance l1 can be less than the length l2 of the hanger 352 of the suspension structure 305 along the longitudinal direction X. Advantageously, a smaller first distance l1 will reduce the impact of the vibration of the transmission shaft 341 caused by the vibration of the motor 303, which is beneficial to structural stability. This design of separating the motor 303 from the fan body 302 no longer places the motor 303 in the duct center shaft, eliminating the mutual influence between the sizes of the motor 303 and the duct center shaft, and allowing the use of a larger motor 303 and a smaller duct center shaft at the same time, which is beneficial to optimizing the aerodynamic performance and overall volume of the electric ducted propulsion device 3.

[0074] like Figure 2 and Figure 3 As shown, the transmission shaft 341 is cylindrical in shape as a whole, and its first end 411 and second end 412 are connected to the motor 303 and the fan body 302 respectively through the first adapter 342 and the second adapter 343. The wheel 324 of the fan body 302 is provided with a protruding piece 325 with a hole protruding in the longitudinal direction X. The two adapters 342 and 343 each include three sections that are pivotally connected, wherein the middle section 34 and 34' are simultaneously connected to the two end sections 35 and 35', and the two end sections 35 and 35' are respectively opened at their ends away from the middle section 34 and 34'. Figure 2 , Figure 3 The orifice shown, preferably, the end sections 35, 35' are both configured as U-shaped chucks. The transmission shaft 341 has through holes 41, 41' radially penetrating therethrough at its first end 411 and second end 412, respectively. Preferably, the two ends of the transmission shaft 341 are shaped as a substantially rectangular parallelepiped, so that the surfaces of the transmission shaft 341 reached by the two ends of the through holes 41, 41' are flat, so as to facilitate connection with the two adapters. Of course, the utility model is not limited thereto, and the first end 411 and the second end 412 of the transmission shaft 341 can also be configured as a cylinder. When assembling the electric ducted propulsion device 3, align the opening of one end section 35, 35' of the first adapter 342 with the through hole 41, 41' of the first end 411 of the transmission shaft 341, and use a fastener such as a stud bolt to pass through the opening and the through hole 41, 41' to connect the first end 411 with the first adapter 342, and connect the other end section 35, 35' of the first adapter 342 to the motor 303; similarly connect the second end 412 of the transmission shaft 341 to one end section 35, 35' of the second adapter 343, and insert the perforated protrusion 325 of the wheel disc 324 into the other end section 35, 35' of the second adapter 343 to connect the wheel disc 324 and the second adapter 343 together. A pivotable adapter is used to connect the motor 303, the transmission shaft 341 and the fan body 302 so that the adapter can reduce or prevent the vibration of the motor 303 from being transmitted to the fan body 302 via the transmission shaft 341 through pivotal movement, thereby improving the operating stability of the electric ducted propulsion device 3.

[0075] like Figures 1 to 3 As shown, the electric ducted propulsion device 3 also includes a suspension structure 305. The suspension structure 305 includes a base barrel 351 disposed at the fan body 302, and a plurality of hangers 352 extending from the outer peripheral surface 511 of the base barrel 351 in the longitudinal direction X. Specifically, the base barrel 351 is shaped into a generally cylindrical shape, and its end closer to the motor 303 is contoured to gradually widen toward the motor 303 along the longitudinal direction X. The base barrel 351 is fixed to surround the duct center cone 321 by means of a plurality of ribs 512 distributed circumferentially, and the ribs 512 are preferably circumferentially spaced at equal angles.

[0076] Each hanger 352 of the hanging structure 305 is circumferentially arranged on the outer surface of the base tube 351 and extends toward the motor 303 along the longitudinal direction X. In the preferred embodiment of the utility model, three hangers 352 are used, and the three hangers 352 are equidistantly spaced (that is, they are spaced about 120° from each other). However, the utility model is not limited to this. Since the hangers 352 need to be embedded in each tail 2 of the aircraft tail structure 100, the circumferential position arrangement of the hangers 352 should be the same as the circumferential position arrangement of the tail 2. If the tail 2 adopts a non-equidistant spacing design, the hangers 352 can also be correspondingly spaced circumferentially at non-uniform angles; in addition, if fewer or more tails 2 are used, a corresponding number of hangers 352 can also be used.

[0077] As shown in the drawings, each hanger 352 may be a frame structure with a plurality of reinforcing ribs 524, and includes a first end 522 and a second end 523 opposite to the first end 522. The hanger 352 may be provided with at least one mounting hole 221 at its first end 522 (two mounting holes 221 arranged along the length direction of the hanger 352 are provided in the preferred embodiment) to facilitate installation in the empennage 2. The second end 523 of the hanger 352 may be provided as a U-shaped clamping member, and the base tube 351 may be provided with a convex block 354 on its outer surface circumferentially to allow the second end 523 of each hanger 352 to be clamped to the corresponding convex block 354. In addition, a pivot shaft 353 (e.g., a stud bolt, etc.) is provided to penetrate the second end 523 of the hanger 352 and the convex block 354 of the base tube 351 to allow the hanger 352 to pivot relative to the base tube 351 about the pivot shaft 353. Preferably, each pivot shaft 353 is positioned to extend in a direction perpendicular to the longitudinal direction X.

[0078] like Figure 4 As shown, the aircraft tail structure 100 includes a tail wing 2 at the rear of the tail body 1. In the preferred embodiment, the tail wing 2 may include three tail wings 2 distributed in a Y shape around the tail body 1, and specifically include two laterally extending outward-inclined vertical tails 201 and a longitudinally extending ventral fin 202. Preferably, in the vertical direction Z, the height of the ventral fin 202 is less than the height of the outward-inclined vertical tail 201. A predetermined angle may be formed between the two outward-inclined vertical tails 201, for example, an angle between 100° and 130°, and preferably, an angle of approximately 120 degrees. The hanger 352 of the suspension structure 305 of the electric ducted propulsion device 3 is as shown in FIG. Figure 4 As shown, the wing roots of the tail fins 2 close to the tail body 1 are respectively embedded in the tail fins 2 (ie, the outward-inclined vertical tail 201 and the ventral fin 202).

[0079] Still Figure 4As shown, the electric ducted propulsion device 3 also includes a fan fairing. The fan fairing is fixed around the base tube 351, enclosing the entire fan body 302 therein, and is combined with the tail 2. Specifically, the outward-inclined vertical tail 201 and the ventral fin 202 respectively accommodate the hanger 352 with their wing roots close to the tail body 1, and extend backward along the longitudinal direction X into the fan fairing to form an integrated structure of the wing-electric ducted propulsion device. This structure hardly adds additional flight resistance, so that the structure and aerodynamic performance of the aircraft including this aircraft tail structure 100 can be optimized at the same time.

[0080] The aircraft tail structure of the utility model includes an electric ducted propulsion device with a split design, in which the motor is arranged away from the fan body, thereby eliminating the mutual influence between the size of the motor and the size of the fan body (especially the duct center cone), so that a large-sized motor and a small-sized duct center cone can be used at the same time, solving the problem of limited motor power or overall bulkiness of the ducted propulsion device in the prior art, and also solving the problem of inconvenient maintenance caused by the motor being in the duct center cone; in addition, the aircraft tail structure of the utility model adopts an integrated design, integrating the hanging structure of the electric ducted propulsion device with the tail wing, so that the electric ducted propulsion device is firmly fixed with the help of the extension structure of the tail wing, solving the problem of low structural strength caused by the narrowing of the tail of the fuselage in the prior art.

[0081] As used herein, the terms "comprises," "comprising," "having," or any further variations thereof, are intended to cover a non-exclusive inclusion. For example, a method, article, or apparatus that includes a list of elements is not necessarily limited to only those elements and may include other elements not expressly listed or inherent to such method, article, or apparatus.

[0082] The present invention is not limited to the above-mentioned embodiments, which are merely illustrative and non-restrictive. Under the guidance of the present invention, those skilled in the art can make any possible changes and modifications without departing from the purpose of the present invention and the scope of protection of the claims. Therefore, any modification, equivalent changes and modifications made to the above-mentioned embodiments based on the technical essence of the present invention without departing from the content of the technical solution of the present invention shall fall within the scope of protection defined by the claims of the present invention.

Claims

1. An aircraft tail structure, wherein the aircraft tail structure is equipped with an electric ducted propulsion device, comprising a tail body, a tail wing installed on the tail body, and the electric ducted propulsion device, wherein: The electric ducted propulsion device comprises: a fan body, the fan body being arranged to be continued from the tail body, comprising a duct center cone and a plurality of fan blades arranged around the duct center cone; A motor, the motor being connected to the duct center cone via a transmission mechanism; It is characterized in that The tail body shrinks rearward along the longitudinal direction to form a shrinkage portion at the tail end of the tail body. The motor is arranged to be spaced apart from the fan body by a first distance in the longitudinal direction so that the motor is located at the front side of the contraction portion, while the fan body is located at the rear side of the contraction portion and is fixed to the inside of the tail body by a motor fixing device.

2. The aircraft tail structure according to claim 1, characterized in that: The electric ducted propulsion device further includes a suspension structure, and the suspension structure includes: A base cylinder, the base cylinder comprising a hollow cylinder, fixed around the duct center cone by means of a plurality of ribs; A plurality of hangers are circumferentially distributed on the base tube and extend along the longitudinal direction.

3. The aircraft tail structure according to claim 2, characterized in that: The plurality of pylons are installed to be buried in the tail wing.

4. The aircraft tail structure according to claim 1, characterized in that: The radial dimension of the motor is larger than the radial dimension of the duct center cone, and / or The radial dimension of the motor is larger than the radial dimension of the contraction portion.

5. The aircraft tail structure according to claim 3, characterized in that: The first distance is greater than a length of the hanger in the longitudinal direction.

6. The aircraft tail structure according to claim 3, characterized in that: The hanger is pivotably connected to the base barrel by means of a pivot shaft.

7. The aircraft tail structure according to claim 3, characterized in that: The hanger includes a frame structure having a plurality of reinforcing ribs.

8. The aircraft tail structure according to claim 1, characterized in that: The motor fixing device comprises a bracket structure respectively fixed to the motor and the inner wall surface of the tail body.

9. The aircraft tail structure according to claim 2, characterized in that: The electric ducted propulsion device further comprises a fan duct fairing, which is arranged to surround the base barrel and is combined with the tail wing.

10. The aircraft tail structure according to claim 1, characterized in that: The tail wing of the aircraft tail structure includes two outward-inclined vertical tails and a ventral fin. When viewed in the longitudinal direction, the outward-inclined vertical tails and the ventral fin are distributed in a Y shape around the tail body.

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