Rotor hub centering structure of a rotorcraft and rotorcraft

Abstract

The application provides a rotor hub centering structure of a rotorcraft and the rotorcraft, belongs to the technical field of rotorcrafts, and is used for centering and assembling a rotor hub of a rotorcraft on a rotor shaft of the rotorcraft. The rotor hub is connected with the rotor shaft through spline connection. The centering structure comprises two centering rings, the two centering rings are sleeved and clamped on the rotor shaft, and the two centering rings are arranged above and below the rotor hub respectively. Two bearing components are sleeved on the rotor shaft, and the two bearing components are connected with the top and bottom of the rotor hub respectively. The inner top and bottom of one of the bearing components are connected with the inner top of one of the centering rings and the rotor hub through taper surfaces respectively. The inner bottom and top of the other bearing component are connected with the inner bottom of the other centering ring and the rotor hub through taper surfaces respectively. The coaxiality of the rotor hub and the rotor shaft is effectively ensured, the high-precision centering of the rotor hub is realized, the accurate control of the rotor torque is facilitated, and the maneuverability of the whole machine is improved.

Description

Technical Field

[0001] This invention belongs to the field of rotorcraft technology, and more specifically, relates to a rotor hub centering structure for a rotorcraft and the rotorcraft itself. Background Technology

[0002] Single-engine unmanned tiltrotor aircraft not only place demands on the power transmission of the hub and rotor shaft connection design, but also on the coaxiality of the assembled hub and rotor shaft. Currently, there are usually three ways to connect the hub and rotor shaft: hub and rotor shaft are connected by a flange, hub and rotor shaft are integrated into a single structure, and hub and rotor shaft are connected by a spline.

[0003] The rotor hub and rotor shaft are connected by a flange, which is commonly used for fixing the rotor hub and rotor shaft of light and small helicopters. This connection method often uses mating surfaces for centering, and the centering performance of this connection method is entirely guaranteed by the machining accuracy of the mating surfaces. Therefore, the requirements for machining accuracy are high, resulting in high production costs. The flanges of the rotor hub and rotor shaft are connected by bolts for circumferential positioning. If this method is used, in order to meet the power transmission design of the rotor hub and rotor shaft connection of a single-engine unmanned tiltrotor aircraft and to bear the huge rotor hub load, the diameter and thickness of the flange will be very large due to the strength limitations of the metal material. At the same time, the bolts for transmitting high power torque will also be very thick, resulting in a significant weight cost.

[0004] The integrated rotor hub and rotor shaft structure is commonly used in light helicopters, especially those with composite material structures. Currently, there are integrated rotor shaft and rotor hub shell designs. This design saves a lot of materials and labor, has good overall stress distribution, simplifies the structure, and improves safety and reliability. However, this structure is not suitable for single-engine unmanned tiltrotor aircraft because composite material structures can no longer withstand rotor hub loads.

[0005] The rotor hub and rotor shaft are connected by a spline. Typically, the rotor hub uses a spline to transmit torque. The rotor hub is tightened by a large nut on the rotor shaft or a rotor hub distribution screw to transmit various external loads. This connection and centering method is relatively safe and reliable. However, this centering structure does not easily guarantee the coaxiality of the rotor hub and rotor shaft, and cannot achieve high-precision centering of the rotor hub. This is not conducive to the precise control of rotor torque and reduces the overall maneuverability of the aircraft. Summary of the Invention

[0006] The purpose of this invention is to address the shortcomings of existing technologies by providing a rotor hub centering structure and a rotorcraft, thereby solving the problems mentioned in the background art. When the existing rotor hub and rotor shaft are connected by a spline, the existing centering method does not easily guarantee the coaxiality of the rotor hub and rotor shaft, cannot achieve high-precision centering of the rotor hub, is not conducive to the precise control of rotor torque, and reduces the overall maneuverability of the aircraft.

[0007] To achieve the above objectives, the present invention provides a rotor hub centering structure for a rotorcraft, used for centering and assembling the rotor hub of a rotorcraft onto the rotor shaft of a rotorcraft, wherein the rotor hub and the rotor shaft are connected by a spline, and the centering structure includes:

[0008] Two centering rings are sleeved and locked onto the rotor shaft, and the two centering rings are respectively disposed above and below the rotor hub;

[0009] Two support components are fitted onto the rotor shaft. The two support components are respectively connected to the top and bottom of the rotor hub. The inner top and bottom of one of the support components are respectively connected to one of the centering rings and the inner top of the rotor hub through conical surfaces. The inner bottom and top of the other support component are respectively connected to the other centering ring and the inner bottom of the rotor hub through conical surfaces.

[0010] Preferably, the centering ring comprises two semi-circular rings, which are able to move toward the rotor shaft when the two first conical surfaces are in contact.

[0011] Preferably, the load-bearing component includes an elastic bearing and a connecting body, the inner top and bottom of the elastic bearing are the inner top and bottom of the load-bearing component, the connecting body is connected to the outer side of the elastic bearing, and the connecting body is connected to the propeller hub.

[0012] Preferably, the rotor hub centering structure of the rotorcraft further includes a pressing component and an annular positioning groove disposed on the rotor shaft. Both centering rings are sleeved in the positioning groove, and the other centering ring abuts against the bottom of the positioning groove. The pressing component is connected to the rotor shaft, and the pressing part of the pressing component abuts against one of the centering rings.

[0013] Preferably, the pressing component is a nut, which is threadedly connected to the rotor shaft, and the nut can move downward along the axial direction of the rotor shaft and press against one of the centering rings.

[0014] Preferably, the spline includes an internal spline and an external spline, the internal spline is connected to the inner side of the center hole of the rotor hub, the external spline is connected to the rotor shaft, and the external spline is sleeved on the internal spline.

[0015] A rotorcraft, comprising:

[0016] Organism;

[0017] A rotor shaft, which is connected to a drive structure within the fuselage;

[0018] The rotor hub is keyed to the rotor shaft.

[0019] The rotor hub centering structure of the gyroplane is connected to the rotor hub and the rotor shaft.

[0020] Preferably, the hub is provided with multiple blades.

[0021] Preferably, the rotorcraft further includes a fairing support bracket, which is disposed above the two centering rings and is connected to the rotor shaft.

[0022] Preferably, when the rotor hub centering structure of the rotor includes a pressing component, the pressing component being a nut, the nut being threadedly connected to the rotor shaft, and the nut being able to move downward along the axis of the rotor shaft and press against one of the centering rings, the fairing upper bracket is connected to the rotor shaft via a spline, a cylinder extends downward from the center hole of the fairing upper bracket, the nut is pressed against the fairing upper bracket, and the bottom of the cylinder is pressed against one of the centering rings.

[0023] This invention provides a rotor hub centering structure for a rotorcraft and the rotorcraft itself. Its advantages are as follows: the inner top and bottom of one of the supporting components of the centering structure are respectively connected to a centering ring and the inner top of the rotor hub via conical surfaces; the inner bottom and top of the other supporting component are respectively connected to another centering ring and the inner bottom of the rotor hub via conical surfaces. The rotor hub's gravity can be transferred to the other centering ring through the conical surface of the other supporting component, and the other centering ring can transfer the rotor hub's gravity to the rotor shaft through surface contact. The rotor hub's lift can be transferred through the conical surface of one of the supporting components. One of the centering rings can transmit the hub lift to the rotor shaft through surface contact. This centering structure, through the centering ring, assists the load-bearing components in bearing the radial force of the shaft, so that the spline only transmits torque. This reduces the amount of motion of the hub in the plane of rotation during rotation, making the hub operation more stable, reducing the vibration level of the rotor system, reducing the risk of rotor system operation, further extending the service life of the rotor system, effectively ensuring the coaxiality of the hub and rotor shaft, achieving high-precision centering of the hub, which is conducive to precise control of rotor torque and improves the overall maneuverability of the aircraft.

[0024] Other features and advantages of the present invention will be described in detail in the following detailed description section. Attached Figure Description

[0025] The above and other objects, features and advantages of the present invention will become more apparent from the more detailed description of exemplary embodiments of the invention in conjunction with the accompanying drawings, wherein the same reference numerals generally represent the same components in the exemplary embodiments of the invention.

[0026] Figure 1A three-dimensional structural schematic diagram of a rotor hub centering structure for a rotorcraft according to an embodiment of the present invention is shown. Figure 1 :

[0027] Figure 2 A three-dimensional structural schematic diagram of a rotor hub centering structure for a rotorcraft according to an embodiment of the present invention is shown. Figure 2 :

[0028] Figure 3 A cross-sectional schematic diagram of a rotor hub centering structure for a rotorcraft according to an embodiment of the present invention is shown:

[0029] Figure 4 A three-dimensional structural diagram of a rotor shaft with a rotor hub centering structure for a rotorcraft according to an embodiment of the present invention is shown:

[0030] Figure 5 A top view schematic diagram of the centering ring structure of a rotor hub centering structure of a rotorcraft according to an embodiment of the present invention is shown.

[0031] Explanation of reference numerals in the attached figures:

[0032] 1. Hub; 2. Rotor shaft; 3. Centering ring; 31. Ring body; 4. Bearing component; 41. Elastic bearing; 42. Connector; 5. Downward pressing component; 6. Fairing upper support. Detailed Implementation

[0033] Preferred embodiments of the invention will now be described in more detail. While preferred embodiments of the invention are described below, it should be understood that the invention can be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided so that the invention will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art.

[0034] like Figures 1-4 As shown, the present invention provides a rotor hub centering structure for a gyroplane, used to center and assemble the rotor hub 1 of the gyroplane onto the rotor shaft 2 of the gyroplane. The rotor hub 1 and the rotor shaft 2 are connected by a spline. The centering structure includes:

[0035] Two centering rings 3 are sleeved and locked onto the rotor shaft 2. The two centering rings 3 are respectively positioned above and below the rotor hub 1.

[0036] Two support components 4 are sleeved on the rotor shaft 2. The two support components 4 are respectively connected to the top and bottom of the rotor hub 1. The inner top and bottom of one support component 4 are respectively connected to one centering ring 3 and the inner top of the rotor hub 1 through a conical surface. The inner bottom and top of the other support component 4 are respectively connected to another centering ring 3 and the inner bottom of the rotor hub 1 through a conical surface.

[0037] Specifically, to address the problem that existing spline connections between the rotor hub and rotor shaft make it difficult to guarantee coaxiality between them, hindering high-precision centering and thus impeding precise rotor torque control and reducing overall aircraft maneuverability, this invention provides a rotor hub centering structure for a gyroplane. In this structure, the inner top and bottom of one supporting component 4 are respectively connected to a centering ring 3 and the inner top of the rotor hub 1 via conical surfaces. Similarly, the inner bottom and top of the other supporting component 4 are respectively connected to another centering ring 3 and the inner bottom of the rotor hub 1 via conical surfaces. The gravity of the rotor hub 1 can be transferred to the other centering ring 3 via the conical surface of the other supporting component 4. The other centering ring 3 can then transfer the gravity of the rotor hub 1 to the rotor shaft 2 through surface contact. The lift of the rotor hub 1 can be transferred to the rotor shaft 2 via the conical surface of one of the supporting components 4. The lift force is transmitted to one of the centering rings 3. The centering ring 3 can transmit the lift force of the rotor hub 1 to the rotor shaft 2 through surface contact. This centering structure, through the centering ring 3, assists the bearing component 4 in bearing the radial force of the shaft in the case of conical connection, so that the spline only transmits torque. This reduces the amount of motion of the rotor hub 1 in the plane of rotation during rotation, making the operation of the rotor hub 1 more stable, reducing the vibration level of the rotor system, reducing the power loss of the rotor system caused by vibration, reducing the risk of rotor system operation, further extending the service life of the rotor system, effectively ensuring the coaxiality of the rotor hub 1 and the rotor shaft 2, realizing high-precision centering of the rotor hub 1, which is conducive to the precise control of rotor torque, thereby reducing the overall vibration level of the aircraft, improving the safety and stability of the aircraft, improving the flight efficiency of the aircraft, and improving the maneuverability of the aircraft.

[0038] like Figure 5 As shown, preferably, the centering ring 3 includes two semi-circular ring bodies 31, which can move closer to the rotor shaft 2 when the two first conical surfaces are in contact.

[0039] Specifically, the centering ring 3 has a split structure, which is convenient for assembly. The centering ring 3 and the rotor shaft 2 can be processed separately. The structure is simple, it is easy to ensure the processing accuracy, and it is easy to control the processing cost.

[0040] Preferably, the bearing component 4 includes an elastic bearing 41 and a connecting body 42. The top and bottom of the inner side of the elastic bearing 41 are the top and bottom of the inner side of the bearing component 4, respectively. The connecting body 42 is connected to the outer side of the elastic bearing 41 and is connected to the propeller hub 1.

[0041] Specifically, the elastic bearing 41 is a radial flapping bearing, and the connecting body 42 is connected to the outer periphery of the propeller hub 1 through a locking member.

[0042] Preferably, the rotor hub centering structure of the rotorcraft also includes a pressing component 5 and an annular positioning groove disposed on the rotor shaft 2. Both centering rings 3 are sleeved in the positioning groove, and the other centering ring 3 abuts against the bottom of the positioning groove. The pressing component 5 is connected to the rotor shaft 2, and the pressing part of the pressing component 5 abuts against one of the centering rings 3.

[0043] Specifically, the pressing and positioning of the pressing component 5 can prevent the centering ring 3, the bearing component 4, and the spline from falling off.

[0044] Preferably, the pressing component 5 is a nut, which is threadedly connected to the rotor shaft 2. The nut can move down along the axial direction of the rotor shaft 2 and press against one of the centering rings 3.

[0045] Specifically, the nut is threaded to the rotor shaft 2 and is used to clamp the centering ring 3, the bearing component 4, and the spline.

[0046] Preferably, the spline includes an internal spline and an external spline. The internal spline is connected to the inside of the center hole of the rotor hub 1, and the external spline is connected to the rotor shaft 2. The external spline is sleeved on the internal spline.

[0047] Specifically, the input torque of the rotor shaft 2 is transmitted to the rotor hub 1 through the combination of internal and external splines.

[0048] A rotorcraft, comprising:

[0049] Organism;

[0050] Rotor shaft 2 is connected to the drive structure inside the fuselage and is arranged longitudinally along the direction of the fuselage.

[0051] Rotor hub 1 is keyed to rotor shaft 2;

[0052] The rotor hub centering structure of the gyroplane is connected to the hub 1 and the rotor shaft 2.

[0053] Preferably, the hub 1 is provided with multiple blades.

[0054] Preferably, the rotorcraft further includes a fairing support 6, which is disposed above the two centering rings 3 and is connected to the rotor shaft 2.

[0055] Preferably, when the rotor hub centering structure of the rotorcraft includes a pressing component 5, the pressing component 5 is a nut, the nut is threadedly connected to the rotor shaft 2, and the nut can move down along the axis of the rotor shaft 2 and press against one of the centering rings 3, the fairing support 6 is connected to the rotor shaft 2 by a spline, the center hole of the fairing support 6 extends downward to a cylinder, the nut is pressed against the fairing support 6, and the bottom of the cylinder is pressed against one of the centering rings 3.

[0056] In summary, when the centering structure of this invention is applied to a rotorcraft, the gravity of the rotor hub 1 can be transmitted to the lower centering ring 3 through the conical surface of the lower elastic bearing. The lower centering ring 3 can then transmit the gravity of the rotor hub 1 to the rotor shaft 2 through surface contact. The lift of the rotor hub 1 can be transmitted to the upper centering ring 3 through the conical surface of the upper elastic bearing. The upper centering ring 3 can then transmit the lift of the rotor hub 1 to the fairing support 6 through surface contact. The fairing support 7 can then transmit the lift of the rotor hub 1 to the locking nut 8 of the rotor shaft 2 through surface contact. The locking nut 8 of the rotor shaft 2 can be transmitted via thread... The connection transmits the lift of the rotor hub 1 to the rotor shaft 1. The centering structure, through the centering ring 3, assists the bearing component 4 in bearing the radial force of the shaft, so that the spline only transmits torque. This reduces the amount of motion of the rotor hub 1 in the plane of rotation during rotation, making the operation of the rotor hub 1 more stable, reducing the vibration level of the rotor system, reducing the risk of rotor system operation, further extending the service life of the rotor system, effectively ensuring the coaxiality of the rotor hub 1 and the rotor shaft 2, realizing high-precision centering of the rotor hub 1, which is conducive to precise control of rotor torque and improves the overall maneuverability of the aircraft.

[0057] The various embodiments of the present invention have been described above. These descriptions are exemplary and not exhaustive, nor are they limited to the disclosed embodiments. Many modifications and variations will be apparent to those skilled in the art without departing from the scope and spirit of the described embodiments.

Claims

1. A rotor hub centering structure for a gyroplane, used for centering and assembling the rotor hub of a gyroplane onto the rotor shaft of a gyroplane, wherein the rotor hub and the rotor shaft are connected by a spline, characterized in that, The centering structure includes: Two centering rings are sleeved and locked onto the rotor shaft, and the two centering rings are respectively disposed above and below the rotor hub; Two support components are sleeved on the rotor shaft. The two support components are respectively connected to the top and bottom of the rotor hub. The inner top and bottom of one of the support components are respectively connected to one of the centering rings and the inner top of the rotor hub through conical surfaces. The inner bottom and top of the other support component are respectively connected to the other centering ring and the inner bottom of the rotor hub through conical surfaces. The centering ring includes two semi-circular ring bodies, which can move toward the rotor shaft when the two conical surfaces are in contact. The load-bearing component includes an elastic bearing and a connecting body. The top and bottom of the inner side of the elastic bearing are the top and bottom of the inner side of the load-bearing component, respectively. The connecting body is connected to the outer side of the elastic bearing and to the propeller hub. The rotor hub centering structure of the rotorcraft also includes a pressing component and an annular positioning groove disposed on the rotor shaft. Both centering rings are sleeved in the positioning groove, and the other centering ring abuts against the bottom of the positioning groove. The pressing component is connected to the rotor shaft, and the pressing part of the pressing component abuts against one of the centering rings.

2. The rotor hub centering structure for a rotorcraft according to claim 1, characterized in that, The pressing component is a nut, which is threaded to the rotor shaft. The nut can move down along the axial direction of the rotor shaft and press against one of the centering rings.

3. The rotor hub centering structure for a rotorcraft according to claim 1, characterized in that, The spline includes an internal spline and an external spline. The internal spline is connected to the inside of the center hole of the rotor hub, and the external spline is connected to the rotor shaft. The external spline is sleeved on the internal spline.

4. A rotorcraft, characterized in that, include: Organism; A rotor shaft, which is connected to a drive structure within the fuselage; The rotor hub is keyed to the rotor shaft. A rotor hub centering structure for a rotorcraft according to any one of claims 1-3, connected to the rotor hub and the rotor shaft.

5. A rotorcraft according to claim 4, characterized in that, The hub is equipped with multiple blades.

6. A rotorcraft according to claim 4, characterized in that, The rotorcraft also includes a fairing support bracket, which is disposed above the two centering rings and is connected to the rotor shaft.

7. A rotorcraft according to claim 6, characterized in that, When the rotor hub centering structure of the rotorcraft includes a pressing component, the pressing component being a nut, the nut being threadedly connected to the rotor shaft, and the nut being able to move downward along the axis of the rotor shaft and press against one of the centering rings, the fairing upper bracket is connected to the rotor shaft via a spline, a cylinder extends downward from the center hole of the fairing upper bracket, the nut is pressed against the fairing upper bracket, and the bottom of the cylinder is pressed against one of the centering rings.

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