WO2015149615A1

WO2015149615A1 - Transmission mechanism and multi-rotor aircraft

Info

Publication number: WO2015149615A1
Application number: PCT/CN2015/074193
Authority: WO
Inventors: 王晨帆
Original assignee: 嘉兴深远世宁航空技术有限公司
Priority date: 2014-04-01
Filing date: 2015-03-13
Publication date: 2015-10-08
Also published as: HK1201014A2; CN104229136A; CN104229136B

Abstract

A transmission mechanism (1) comprises a supporting frame (11); a transmission shaft (12) mounted on the supporting frame (11), the power generated by a power part (4) being transmitted to a driven part (6) via the transmission shaft (12); and a bearing assembly (13) mounted on the transmission shaft (12). The bearing assembly (13) comprises a flexible bearing (14) and a support bearing (15). The flexible bearing (14) has an outer ring (16) and an inner ring (17), the inner surface of the outer ring (16) is a spherical surface, and the inner ring (17) is rotatably mounted on the outer ring (16) around the spherical center of the spherical surface. The outer ring (16) is fixed on the inner wall of the supporting frame (11), and the inner ring (17) is mounted on the support bearing (15), and the support bearing (15) is assembled on the transmission shaft (12). The supporting frame (11) drives the bearing assembly (13) supporting the transmission shaft (12) to deflect after the supporting frame is bent. Because of the rotatable connection between the outer ring (16) and the inner ring (17) of the flexible bearing (14) in the bearing assembly (13), the supporting frame (11) is prevented from transmitting the bending stress generated by bending to the transmission shaft (12), and therefore the damage to the transmission shaft (12) is avoided.

Description

Transmission mechanism and multi-rotor aircraft

Technical field

This invention relates to the field of transmissions and, more particularly, to a transmission mechanism and a multi-rotor aircraft.

Background technique

Multi-rotor aircraft has been recognized and promoted by the market for its good stability and maneuverability. At present, the world's multi-rotor aircraft are mostly electric multi-rotor aircraft, the most common ones are electric four-rotor and electric six-rotor aircraft. An important feature is the use of batteries as an energy source, the motor as a power source, and the motor directly connected to the rotor.

Due to the limitation of battery capacity, the electric multi-rotor aircraft has a short flight time (time of flight), generally no more than one hour. Similarly, due to the limitation of battery capacity, the electric multi-rotor aircraft can withstand relatively small loads, and the total weight is generally less than 30 kg. The above limitations of loads and voyages have limited application scenarios for multi-rotor aircraft.

At present, a possible solution is to use a hydraulic engine instead of a motor as a power source. Because the oil is liquid, lighter in weight and provides sufficient power, it can greatly increase the time and payload of a multi-rotor aircraft.

However, compared with the motor, the oil-powered engine has a slow reaction speed and the reaction process is highly nonlinear. If a rotor engine is directly connected to each rotor, it will not only make the multi-rotor aircraft costly, but also face the problem of coordinated control of the multi-rotor aircraft. One possible solution to the above problem is to utilize a drive shaft between the oil-powered engine and each of the rotors so that the oil-powered transmitter provides power to each of the rotors.

In the above solution, the oil-powered engine and the rotor are respectively located at both ends of the support frame supporting the transmission shaft. The support frame inevitably bends under the action of an external force (such as the tension generated by the rotor, the gravity of the rotor portion, or the gravity generated by the support member). The bending stress caused by the bending of the support frame is transmitted to the transmission shaft through the support bearing inside the support frame, thereby causing deformation of the transmission shaft and causing damage to the transmission shaft.

Summary of the invention

Embodiments of the present invention provide a transmission mechanism and a multi-rotor aircraft to prevent the transmission shaft from being bent Deformation problems under stress.

In a first aspect, a transmission mechanism is provided, comprising: a support frame, one end is connected to the power part, and the other end is connected to the driven part, and in the working state of the transmission mechanism, the bending moment generated by the external force of the support frame is greater than a drive shaft mounted on the support frame, the power generated by the power portion is transmitted to the driven portion through the drive shaft; a bearing assembly mounted on the drive shaft, including a flexible bearing and a support a bearing, the flexible bearing comprising an outer ring and an inner ring, the inner surface of the outer ring being a spherical surface, the inner ring being rotatably mounted in the outer ring along a spherical center of the spherical surface, the outer ring being fixed On the inner wall of the support frame, the inner ring is mounted on the support bearing, and the support bearing is mounted on the drive shaft.

In conjunction with the first aspect, in an implementation of the first aspect, the drive shaft includes: an input end coupled to the power portion; an output end coupled to the driven portion; at the input end and a shaft unit between the output ends, the shaft unit comprising a shaft segment and the bearing assembly mounted on the shaft segment; wherein the input end, the shaft unit and the output end pass through The shafts are connected in sequence.

In conjunction with the first aspect, or any one of the foregoing implementation manners, in another implementation manner of the first aspect, the input end and the output end comprise N segments of the axis unit, and the N segments of the axis The units are sequentially connected by a coupling, wherein N is determined by the degree of bending of the support frame under the bending moment and the angular compensation amount of the coupling on the transmission shaft.

In conjunction with the first aspect, or any one of the above implementations, in another implementation of the first aspect, the power portion includes a hydraulic engine, and a rotating shaft of the oil motor is coupled to one end of the transmission shaft The driven portion includes a rotor, and a rotating shaft of the rotor is coupled to the other end of the drive shaft.

In a second aspect, a multi-rotor aircraft is provided, comprising: a body mounted with an oil-powered engine; at least three rotor portions distributed along a circumference centered on a center of the body, the rotor portion and the body being respectively mounted on At both ends of the support frame, the oil-powered engine transmits power to the rotor portion through a drive shaft mounted on the support frame; a bearing assembly mounted on the drive shaft, including a flexible bearing and a support bearing, The flexible bearing includes an outer ring and an inner ring, the inner surface of the outer ring being a spherical surface, the inner ring being rotatably mounted in the outer ring along a spherical center of the spherical surface, the outer ring being fixed in the outer ring On the inner wall of the support frame, the inner ring is mounted on the support bearing, and the support bearing is mounted on the drive shaft.

In conjunction with the second aspect, in an implementation of the second aspect, the drive shaft includes: An input end to which the oil motor is coupled; an output end coupled to the rotor portion at the other end of the drive shaft; an axle unit between the input end and the output end, the shaft unit including the shaft segment and mounted on The bearing assembly on the shaft segment; wherein the input end, the shaft unit and the output end are sequentially connected by a coupling.

In conjunction with the second aspect, or any one of the foregoing implementation manners, in another implementation manner of the second aspect, the input end and the output end include N segments of the axis unit, and the N segment of the axis The units are sequentially connected by a coupling, wherein N is determined by the degree of bending of the support frame under the bending moment and the angular compensation amount of the coupling on the transmission shaft.

In conjunction with the second aspect, or any one of the above implementations, in another implementation of the second aspect, the rotor portion includes: a rotor shaft coupled to an output end of the drive shaft; An inclinator on the shaft, the inner ring of the recliner being in engagement with the rotor shaft.

In conjunction with the second aspect, or any one of the above implementations, in another implementation of the second aspect, the at least three rotor portions are four rotor portions.

In conjunction with the second aspect, or any one of the above implementations, in another implementation of the second aspect, the at least three rotor portions are six rotor portions.

In the embodiment of the present invention, since the support frame is connected with the rotor portion, a vertical pulling force is generated when the rotor portion is working, which causes the support frame to be bent and deformed. After the support frame is bent, the bearing assembly supporting the drive shaft is deflected. Due to the rotatably connected between the outer ring and the inner ring of the flexible bearing in the bearing assembly, the support frame is prevented from transmitting the bending stress generated by the bending to the transmission shaft, thereby avoiding the damage of the transmission shaft.

DRAWINGS

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings to be used in the embodiments of the present invention will be briefly described below. It is obvious that the drawings described below are only some embodiments of the present invention, Those skilled in the art can also obtain other drawings based on these drawings without paying any creative work.

BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is a cross-sectional view showing a transmission mechanism of an embodiment of the present invention.

Figure 2 is a cross-sectional view showing a transmission mechanism in a bent state according to an embodiment of the present invention.

Figure 3 is a cross-sectional view of a transmission mechanism in accordance with one embodiment of the present invention.

Figure 4 is a cross-sectional view of a transmission mechanism in accordance with one embodiment of the present invention.

Figure 5 is a cross-sectional view of a transmission mechanism in accordance with one embodiment of the present invention.

Figure 6 is a structural view of a flexible bearing according to an embodiment of the present invention.

Figure 7 is a top plan view of a quadrotor aircraft in accordance with one embodiment of the present invention.

Figure 8 is a top plan view of a quadrotor aircraft in accordance with one embodiment of the present invention.

Figure 9 is a top plan view of a quadrotor aircraft in accordance with one embodiment of the present invention.

Figure 10 is a top plan view of a six-rotor aircraft in accordance with one embodiment of the present invention.

Figure 11 is a plan view of a six-rotor aircraft in accordance with one embodiment of the present invention.

Figure 12 is a plan view of a six-rotor aircraft in accordance with one embodiment of the present invention.

Figure 13 is a cross-sectional view of the quadrotor of Figure 6 taken along line A-A.

Figure 14 is a cross-sectional view of the quadrotor of Figure 6 taken along line B-B.

Figure 15 is a cross-sectional view of the quadrotor of Figure 8 taken along line A-A.

Figure 16 is a cross-sectional view of the quadrotor of Figure 8 taken along line B-B.

detailed description

The technical solutions in the embodiments of the present invention are clearly and completely described in the following with reference to the accompanying drawings in the embodiments of the present invention. It is obvious that the described embodiments are a part of the embodiments of the present invention, but not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative efforts shall fall within the scope of the present invention.

Referring to Figures 1 to 5, the transmission mechanism 1 comprises:

Support frame 11. The support frame 11 has one end connected to the power portion 4 and the other end connected to the driven portion 6. In the operating state of the transmission mechanism 1, the external force generated by the external force of the support frame 11 is greater than zero.

The drive shaft 12 mounted on the support frame 11 transmits the power generated by the power portion 4 to the driven portion 6 through the drive shaft 12.

A bearing assembly 13 is mounted on the drive shaft 12. The bearing assembly 13 includes a flexible bearing 14 and a support bearing 15. The flexible bearing 14 includes an outer ring 16 having an inner surface which is spherical, an inner ring 17 rotatably mounted in the outer ring 16 along the spherical center of the spherical surface, and an outer ring 16 fixed to the inner wall of the support frame 11. Upper, inner ring 17 is mounted on support bearing 15, and support bearing 15 is mounted on drive shaft 12.

In the embodiment of the present invention, since the bending moment generated by the external force of the support frame is greater than 0, the support frame may be bent under the action of the bending moment. After the support frame is bent, the bearing assembly supporting the drive shaft is deflected. Due to the rotatably connected between the outer ring and the inner ring of the flexible bearing in the bearing assembly, the support frame is prevented from transmitting the bending stress generated by the bending to the transmission shaft, thereby avoiding the damage of the transmission shaft.

The flexible bearing 14 can adopt the structure shown in FIG. As can be seen from Figure 6, the inner surface of the outer ring 16 is a spherical surface, the outer surface of the inner ring 17 is also spherical, and the inner ring 17 is spherically movable along the inner surface of the outer ring 16.

It should be understood that the support bearing 15 in the bearing assembly 13 functions to support the drive shaft 15. The specific type of the support bearing 15 is not limited in the embodiment of the present invention, and may be, for example, a self-aligning ball bearing, a deep groove ball bearing, or the like. In addition, the number of the support bearings 15 included in one bearing assembly 13 may be one or plural, and may be determined depending on factors such as support and positioning, and the size of the inner ring 17.

It should be understood that the above-described support frame 11 may be a frame, a truss or a tubular form or the like.

In an embodiment of the invention, the drive shaft 12 can be an integrally formed through shaft having one or more bearing assemblies 13 disposed thereon.

Alternatively, as an embodiment, the drive shaft 12 may include an input end 18 coupled to the power section 4, an output end 19 coupled to the driven portion 6, and an axle unit located between the input end 18 and the output end 19. 20. The shaft unit 20 may include a shaft section 21 and a bearing assembly 13 mounted on the shaft section 21; wherein the input end 18, the shaft unit 20 and the output end 19 are sequentially connected by a coupling 22.

In the embodiment of the invention, the inside of the transmission shaft is connected by a coupling. The coupling not only serves as a connection but also compensates for the angular deflection of the shaft caused by the bending of the support frame.

Specifically, an N-stage shaft unit 20 may be included between the input end 18 and the output end 19, and the N-stage shaft units 20 are sequentially connected by a coupling 22, wherein N is bent by the support frame 11 under the bending moment. The amount of angular compensation of the coupling 22 on the drive shaft 12 is determined. The support frame 11 is bent under the action of an external force (for example, the gravity of the support member, the gravity of the driven portion 6, or the pulling force generated by the driven portion 6 (such as a rotor), etc., the input end 18 and the output end 19 The axis between them will produce a certain deflection angle (depending on the magnitude of the external force). At this time, the number of the shaft units 20 can be determined by the length of the transmission distance and the degree of bending of the support frame 11, and the basis for the determination can be: the input end 18, each of the shaft segments 21 and the output end 19, between the adjacent two components The angle is smaller than the allowable angular compensation amount of the coupling connected thereto, and if the angle is larger than the angular compensation amount allowed by the coupling, the number of the shaft units 20 is increased. For example, referring to FIG. 1 to FIG. 3, it is assumed that under the action of external force, the maximum deflection angle generated by the support frame 11 is 2 degrees, and the allowable angle compensation amount of each coupling 22 is 1 degree, then it can be input. One shaft unit 20 is disposed between the end 18 and the output end 19. The input end 18, the output end 19 and the shaft unit 20 are sequentially connected through a coupling 22 and a total of two couplings. Since each coupling 22 can compensate for a deflection angle of 1 degree, the two couplings can compensate for a deflection angle of 2 degrees. Can meet the compensation needs of the maximum deflection angle. For further example, referring to FIG. 4 to FIG. 5, it is assumed that under the action of an external force, the maximum deflection angle generated by the support frame 11 is 3 degrees, and the allowable angle compensation amount of each coupling 22 is 1 degree, then Two shaft units 20 are provided between the input end 18 and the output end 19. The input end 18, the output end 19 and the shaft unit 20 are sequentially connected through a coupling 22 and a total of two couplings. Since each coupling 22 can compensate for a deflection angle of 1 degree, the three couplings can compensate for a deflection angle of 3 degrees at the maximum, which can meet the compensation requirement of the maximum deflection angle.

It should be understood that in the shaft unit 20, the bearing assembly 13 sleeved on the shaft section 21 may be one or plural. The position of the bearing assembly 13 on the shaft section 21 can also be variously defined, which is not specifically limited in the embodiment of the present invention. For example, referring to FIGS. 3 and 4, one shaft unit 20 includes a bearing assembly 13 that is disposed at an intermediate portion of the shaft section 21. As another example, referring to Figs. 1, 2 and 5, one shaft unit 20 includes two bearing assemblies 13 which are respectively disposed at both ends of the shaft section 21. Of course, the number of the bearing assemblies 13 in the one shaft unit 20 may also be three or even more. The arrangement of the bearing assembly 13 on the shaft section 21 may also adopt other arrangements, depending on the shaft section 21 The length and actual positioning requirements are arranged.

It should be understood that the specific type of the power portion 4 and the driven portion 6 is not limited in the embodiment of the present invention. For example, the power portion 4 may include a hydraulic engine, and the rotating shaft of the oil engine is connected to one end of the transmission shaft 12; the driven portion 6 Including a rotor, the shaft of the rotor is coupled to the other end of the drive shaft 12. When the transmission mechanism is in operation, the rotor generates a large pulling force, and under the action of the pulling force, the support frame is caused to bend. The bearing assembly of the embodiment of the invention can effectively prevent the support frame from transmitting the stress generated by the bending to the transmission shaft. Up, thereby avoiding deformation of the drive shaft.

It should be noted that the foregoing is only an example of an application scenario of the embodiment of the present invention, and the embodiment of the present invention is not limited to the scenario. The transmission mechanism of the embodiment of the present invention can avoid the deformation problem of the transmission shaft by using the transmission mechanism of the embodiment of the present invention, as long as the transmission mechanism is working and the external force of the support frame supporting the transmission shaft is greater than 0. It is within the scope of protection of the embodiments of the present invention.

The transmission mechanism of the embodiment of the present invention has been described in detail above with reference to Figs. The multi-rotor aircraft of the embodiment of the present invention will be described in detail below with reference to FIGS. 7 through 16. It should be noted that the multi-rotor aircraft described hereinafter may employ the transmission mechanism 1 described with reference to FIGS. 1 to 6, and redundant description will be appropriately omitted to avoid redundancy.

Referring to FIGS. 7-16, the multi-rotor aircraft 7 may include a body 41 to which an oil motor 42 is mounted. At least three rotor portions 6 distributed along a circumference centered on the center of the body 41, the rotor The portion 6 and the body 41 are mounted at both ends of the support frame 11, respectively. The oil motor 42 is powered to the rotor portion 6 by a drive shaft 12 mounted on the support frame 11. The bearing assembly 13 assembled on the transmission shaft 12 includes a flexible bearing 14 including an outer ring 16 and an inner ring 17, and a support bearing 15, the inner surface of the outer ring 16 being spherical, and the inner ring 17 being along the spherical center of the sphere Rotatingly mounted in the outer ring 16, the outer ring 16 is fixed to the inner wall of the support frame 11, the inner ring 17 is mounted on the support bearing 15, and the support bearing 15 is mounted on the drive shaft 12.

It should be understood that the at least three rotor portions 6 described above may be evenly distributed along the circumference centered on the center of the body 41, or may be non-uniformly distributed.

Alternatively, as an embodiment, referring to Figures 7-9, the multi-rotor aircraft 7 may include four rotor portions 6 centered around the body 41 and distributed around the body in a cross or X shape. Alternatively, referring to Figures 10 through 12, the multi-rotor aircraft 7 may include six rotor portions 6 that are centered about the body 41 and evenly distributed around them.

It should be understood that the number and position of the oil motor 42 are not specifically limited in the embodiment of the present invention. For example, the multi-rotor aircraft 7 may include a single oil motor 42 that is disposed at a position as shown in FIG. 7 or FIG. As another example, the multi-rotor aircraft 7 includes two oil-powered engines 42 that are assembled in a manner as shown in FIG. 8 or FIG. As another example, the multi-rotor aircraft 7 includes four oil-powered engines 42 that are assembled in a manner as shown in FIG. 9 or FIG. Of course, the multi-rotor aircraft 7 may also include three or other number of oil-powered engines, and the number of oil-powered engines may be determined based on factors such as the power demand of the aircraft and the power that each engine can provide.

Alternatively, as an embodiment, the drive shaft 12 may include an input 18 coupled to the oil motor 42 and an output 19 coupled to the rotor portion 6 at the other end of the drive shaft 12; at the input 18 and the output A shaft unit 20 between 19, the shaft unit 20 may include a shaft section 21 and a bearing assembly 13 mounted on the shaft section 21; wherein the input end 18, the shaft unit 20 and the output end 19 are sequentially connected by a coupling 22 .

In the embodiment of the invention, the inside of the transmission shaft is connected by a coupling. The coupling not only works as a connection It also serves to compensate for the angular deflection of the axis caused by the bending of the support frame.

Optionally, as an embodiment, an N-stage shaft unit 20 is included between the input end 18 and the output end 19, and the N-section shaft units 20 are sequentially connected by a coupling 22, wherein N is supported by the support frame 11 at a bending moment. The degree of bending under action and the amount of angular compensation of the coupling 22 on the drive shaft 12 are determined.

Alternatively, as an embodiment, referring to Figures 13-16, the rotor portion 6 may include a rotor shaft 61 coupled to the output end 18 of the drive shaft 12; a tilter 62 mounted on the rotor shaft 61, the recliner 62 The inner ring 63 is attached to the rotor shaft 61. In the prior art, the inner ring 63 of the tilter 62 is mounted on the rotor shaft 61 by ball bearings, so that the structure of the tilter 62 and the rotor shaft 61 is too complicated, which increases the difficulty of assembly and reduces the reliability. The inner ring of the middle recliner 62 directly abuts the rotor shaft 61, which greatly simplifies the structure between the recliner and the rotor shaft 61, and improves reliability.

Specifically, the recliner 62 is a part of a steering assembly that manipulates the total distance of the rotor. The steering assembly sequentially connects the variable pitch rocker arm, the variable pitch rocker link, the outer ring of the tilter, and the inner ring of the tilter from top to bottom. , tilting inner ring torsion arm, clamp, recliner outer ring torsion arm, steering gear connecting rod and steering gear. The recliner 62 is mainly composed of a recliner outer ring, a recliner inner ring 63, and a bearing connected therebetween, the recliner 62 being fitted on the rotor shaft 61 and slidable along the axial direction of the rotor shaft 61, inclined The outer ring does not rotate with the rotor shaft 61 under the action of the outer ring torsion arm of the recliner, and the inner ring 63 rotates with the rotor shaft 61 under the action of the inner ring torsion arm of the recliner. The rotor portion 6 includes a steering gear, and the steering gear link connected to the steering gear drives the tilter 62 to slide along the rotor shaft 61, thereby driving the variable pitch rocker link connected to the tilter 62 to move up and down, thereby driving the variable distance. The rocker arm rotates around the pitch-changing axis of the propeller to achieve the purpose of manipulating the total distance of the rotor.

It should be understood that the embodiment of the present invention does not specifically define the structure between the input end 18 of the oil motor 42 and the transmission shaft 12 and the output end 19 of the transmission shaft 12. The transmission forms are various, and the specific transmission forms are given below. Example.

Referring to FIGS. 13-16, the oil motor 42 can be mounted on the first reduction gearbox 44 via the engine mount 43. The power input shaft 45 is coupled to the oil motor 42 and is rotated by the oil motor 42. The power input shaft 45 is supported on the first reduction gear box 44 by the first support bearing 46. The end of the power input shaft 45 is connected to the first bevel gear 47. The first bevel gear 47 meshes with the second bevel gear 23, and the second bevel gear 23 is connected to the input end 18. The input end 18 is supported on the first reduction gear box 44 by a second support bearing 24. The output end 19 is supported on the second reduction gear box 64 by a third support bearing 25. The end of the output end 19 is connected to the third bevel gear 26, the third bevel gear 26 and the The four bevel gears 65 mesh. The fourth bevel gear 65 is coupled to the rotor shaft 61, and the rotor shaft 61 is supported by the second reduction gear 64 via the fourth support bearing 66. The rotor shaft 61 is coupled to the rotor 67 to drive the rotor 67 to rotate.

In addition, the oil motor 42 receives signals from the flight control system via the engine control wire 48 to control the power of the oil motor 42. The multi-rotor aircraft 7 may also include user equipment, parachutes, and the like.

In the several embodiments provided by the present application, it should be understood that the disclosed systems, devices, and methods may be implemented in other manners. For example, the device embodiments described above are merely illustrative. For example, the division of the unit is only a logical function division. In actual implementation, there may be another division manner, for example, multiple units or components may be combined or Can be integrated into another system, or some features can be ignored or not executed. In addition, the mutual coupling or direct coupling or communication connection shown or discussed may be an indirect coupling or communication connection through some interface, device or unit, and may be in an electrical, mechanical or other form.

The units described as separate components may or may not be physically separated, and the components displayed as units may or may not be physical units, that is, may be located in one place, or may be distributed to multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of the embodiment.

The above is only a specific embodiment of the present invention, but the scope of the present invention is not limited thereto, and any person skilled in the art can easily think of changes or substitutions within the technical scope of the present invention. It should be covered by the scope of the present invention. Therefore, the scope of the invention should be determined by the scope of the claims.

Claims

A transmission mechanism, comprising:

a support frame, one end is connected to the power part, the other end is connected to the driven part, in the working state of the transmission mechanism, the bending force generated by the external force of the support frame is greater than 0;

a drive shaft mounted on the support frame, the power generated by the power portion is transmitted to the driven portion through the drive shaft;

a bearing assembly mounted on the drive shaft, comprising a flexible bearing and an inner bearing, the flexible bearing comprising an outer ring and an inner ring, the inner surface of the outer ring being a spherical surface, the inner ring being along a spherical center of the sphere Rotatablely mounted in the outer ring, the outer ring is fixed to an inner wall of the support frame, the inner ring is mounted on the support bearing, and the support bearing is mounted on the drive shaft.
The transmission mechanism of claim 1 wherein said drive shaft comprises:

An input connected to the power portion;

An output connected to the driven portion;

a shaft unit between the input end and the output end, the shaft unit including a shaft segment and the bearing assembly mounted on the shaft segment;

Wherein, the input end, the shaft unit and the output end are sequentially connected by a coupling.
The transmission mechanism according to claim 2, wherein the input end and the output end comprise N segments of the shaft unit, and the N segments of the shaft units are sequentially connected by a coupling, wherein N is determined by the degree of bending of the support frame under the bending moment and the angular compensation amount of the coupling on the drive shaft.
The transmission mechanism according to any one of claims 1 to 3, wherein the power portion includes an oil-operated engine, and a rotating shaft of the oil-powered engine is coupled to one end of the transmission shaft; A rotor is included, and a rotating shaft of the rotor is coupled to the other end of the drive shaft.
A multi-rotor aircraft characterized by comprising:

The body is equipped with a hydraulic engine;

At least three rotor portions distributed along a circumference centered on a center of the body, the rotor portion and the body are respectively mounted at both ends of the support frame, and the oil-driven engine is driven by the support mounted on the support frame The shaft transmits power to the rotor portion;

a bearing assembly mounted on the drive shaft, comprising a flexible bearing and an inner bearing, the flexible bearing comprising an outer ring and an inner ring, the inner surface of the outer ring being a spherical surface, the inner ring being along a spherical center of the sphere Rotatablely mounted in the outer ring, the outer ring being fixed to an inner wall of the support frame, An inner ring is mounted on the support bearing, and the support bearing is mounted on the drive shaft.
The multi-rotor aircraft of claim 5 wherein said drive shaft comprises:

An input connected to the oil-operated engine;

An output connected to a rotor portion located at the other end of the drive shaft;

a shaft unit between the input end and the output end, the shaft unit including a shaft segment and the bearing assembly mounted on the shaft segment;

Wherein, the input end, the shaft unit and the output end are sequentially connected by a coupling.
The multi-rotor aircraft according to claim 6, wherein the input end and the output end comprise N segments of the shaft unit, and the N segments of the shaft units are sequentially connected by a coupling, wherein N is determined by the degree of bending of the support frame under the bending moment and the angular compensation amount of the coupling on the drive shaft.
A multi-rotor aircraft according to any of claims 5-7, wherein the rotor portion comprises:

a rotor shaft coupled to the output end of the drive shaft;

An incliner mounted on the rotor shaft, the inner ring of the recliner being in engagement with the rotor shaft.
A multi-rotor aircraft according to any one of claims 5-8, wherein the at least three rotor portions are four rotor portions.
The multi-rotor aircraft of any of claims 5-8, wherein the at least three rotor portions are six rotor portions.