A flexible rotor hub for helicopters

Abstract

This utility model provides a flexible rotor hub for helicopters, relating to the field of flexible rotor connection technology. It includes a fixed block with a transmission assembly inside, and a damping assembly. The damping assembly includes a top plate fixedly connected to both ends of the outer side of the fixed block, with a first bolt threaded inside the top plate and a damping rod sleeved outside the first bolt. A tension-torsion connection assembly includes tension-torsion bodies fixedly connected to both ends of the fixed block, with a wheel sleeved at the end of the tension-torsion body furthest from the fixed block. A second bolt is threaded inside the top plate, and the damping rod is fixedly connected to the top plate via the second bolt. Base plates are fixedly connected to both sides of the bottom of the fixed block. This design effectively absorbs vibration energy, distributes loads to reduce component fatigue, adapts to minor deformations to reduce stress concentration, thereby reducing complex metal bearings, hinges, and other components, and lowering the overall weight.

Description

Technical Field

[0001] This utility model relates to the field of flexible rotor connection technology for helicopters, and in particular to a flexible rotor hub for helicopters. Background Technology

[0002] The rotor hub is the core component of a helicopter, connecting the rotor blades to the main shaft. It is responsible for transmitting lift and torque and enabling the flapping, twitching, and pitch-changing motion of the blades. Traditional helicopter rotor hubs generally employ all-metal mechanical structures, such as articulated, semi-articulated, or hingeless structures. These structures are typically made of aluminum or titanium alloys and rely on complex mechanical components such as metal bearings, hinges, dampers, and linkages to achieve their functions.

[0003] Traditional all-metal rotor hubs are heavy, have high metal density, and have many complex mechanical connections, resulting in a high proportion of rotor hub weight in the whole machine. This directly affects the payload and fuel efficiency. They require multiple bearings, hinges, and dampers, making the manufacturing and assembly processes complex and prone to sudden failures due to lubrication failure or fatigue cracks.

[0004] Therefore, this utility model provides a flexible rotor hub for helicopters. Utility Model Content

[0005] The purpose of this invention is to overcome the shortcomings of existing technologies and provide a flexible rotor hub for helicopters.

[0006] To achieve the above objectives, the present invention adopts the following technical solution: a flexible rotor hub for helicopters, including a fixed block, a transmission component is provided inside the fixed block, and a damping component is also included. The damping component includes a top plate fixedly connected to both ends of the outer side of the fixed block, a first bolt is threaded inside the top plate, and a damping rod is sleeved on the outer side of the first bolt.

[0007] A tension-torsion connection assembly, comprising tension-torsion bodies fixedly connected to both ends inside a fixed block, wherein a rotating wheel is fitted onto the end of the tension-torsion body away from the fixed block.

[0008] In a preferred embodiment, the top plate is internally threaded with a second bolt, and the damping rod is fixedly connected to the top plate by the second bolt.

[0009] In a preferred embodiment, a base plate is fixedly connected to both sides of the bottom end of the fixing block.

[0010] In a preferred embodiment, a nut is rotatably connected to the bottom end of the base plate, and the internal thread of the nut is connected to the outside of the first bolt and the second bolt.

[0011] In a preferred embodiment, the top plate is internally connected to an extension rod threaded bolt, and the outer bottom end of the extension rod threaded bolt is threaded with a connecting cap.

[0012] In a preferred embodiment, the inside of the rotating wheel is movably connected to the threaded bolt of the extension rod, and both outer ends of the rotating wheel are rotatably connected to the near ends of the top plate and the bottom plate.

[0013] In a preferred embodiment, the transmission assembly includes a slot formed inside the fixed block, a locking pin slidably connected to the slot, and a transmission rod fixedly connected to the bottom end of the locking pin.

[0014] In a preferred embodiment, blades are fixedly connected to the adjacent side of the top plate and the bottom plate.

[0015] In a preferred embodiment, the tension-torsion body uses steel wire, plastic steel wire, Kevlar wire, carbon fiber, glass fiber, graphene composite material, woven individually or in combination.

[0016] Compared with the prior art, the advantages and positive effects of this utility model are as follows:

[0017] This invention utilizes the force generated by the rotation of the blades to drive the top and bottom plates, which in turn drive the first bolt, the second bolt, and the damping rod. The deformation of the damping rod absorbs energy, and the two bolts distribute the load. Simultaneously, the blades drive the impeller and the threaded bolt of the extension rod, which in turn pulls the tension-torsion body to transmit force to the fixed block. The fixed block drives the slot, the locking pin, and the transmission rod to achieve specific movements. This design effectively absorbs vibration energy, distributes load to reduce component fatigue, and adapts to small deformations to reduce stress concentration, thereby reducing the number of complex metal bearings, hinges, and other components, and lowering the overall weight. Attached Figure Description

[0018] Figure 1 A perspective view of a flexible rotor hub for a helicopter provided by this utility model;

[0019] Figure 2 A schematic diagram of the blade structure of a flexible rotor hub for a helicopter provided by this utility model;

[0020] Figure 3 A schematic diagram of a damping component structure for a helicopter flexible rotor hub provided by this utility model;

[0021] Figure 4 for Figure 1 Enlarged view of point A in the image;

[0022] Figure 5 This utility model provides a schematic diagram of the transmission assembly structure of a helicopter flexible rotor hub.

[0023] Legend:

[0024] 1. Fixed block;

[0025] 2. Damping assembly; 21. Top plate; 22. First bolt; 23. Damping rod; 24. Second bolt; 25. Base plate; 26. Nut;

[0026] 3. Pull-torque connection assembly; 31. Extension rod threaded bolt; 32. Rotary wheel; 33. Pull-torque; 34. Connecting cap;

[0027] 4. Transmission assembly; 41. Transmission rod; 42. Locking pin; 43. Locking slot;

[0028] 5. Paddle blades. Detailed Implementation

[0029] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0030] like Figure 1 - Figure 3 As shown, this embodiment provides a technical solution: a flexible rotor hub for helicopters, including a fixed block 1 and a damping assembly 2. The damping assembly 2 includes a top plate 21 fixedly connected to both ends of the outer side of the fixed block 1. A first bolt 22 is threadedly connected to the inside of the top plate 21, and a damping rod 23 is sleeved on the outside of the first bolt 22. A second bolt 24 is threadedly connected to the inside of the top plate 21, and the damping rod 23 is fixedly connected to the top plate 21 by the second bolt 24. A bottom plate 25 is fixedly connected to both sides of the bottom end of the fixed block 1. A nut 26 is rotatably connected to the bottom end of the bottom plate 25, and the nut 26 is threadedly connected to the outside of the first bolt 22 and the second bolt 24. A rotor blade 5 is fixedly connected to the side of the top plate 21 and the bottom plate 25 that is close to each other.

[0031] The top plate 21 serves as the rigid connection base for the blade 5. The damping rod 23 is fixed by bolts to form a multi-level elastic support. The double bolt design of the first bolt 22 and the second bolt 24 enhances the stability of the damping rod 23, disperses the centrifugal force and vibration load when the blade 5 rotates, reduces the risk of bolt fatigue fracture, and the threaded connection facilitates disassembly and maintenance, reducing maintenance costs. The damping rod 23 is an elastic buffer element that absorbs the energy of the blade 5 flapping and oscillating, reduces the transmission of blade 5 vibration to the transmission system, improves flight stability, and extends gearbox life. The bottom plate 25 and the nut 26 form a clamping structure with the top plate 21 to fix the root of the blade 5. The nut 26 locks the bolts, enhancing the torsional stiffness of the root of the blade 5 and preventing excessive displacement of the blade 5 under high load.

[0032] like Figure 2 - Figure 3 As shown, the tension-torsion connection assembly 3 includes tension-torsion bodies 33 fixedly connected to both ends inside the fixed block 1. A rotating wheel 32 is sleeved on the end of the tension-torsion body 33 away from the fixed block 1. An extension rod threaded bolt 31 is movably connected inside the top plate 21, and a connecting cap 34 is threadedly connected to the bottom outer end of the extension rod threaded bolt 31. The rotating wheel 32 is movably connected inside the extension rod threaded bolt 31, and both ends of the outer side of the rotating wheel 32 are rotatably connected to the ends of the top plate 21 and the bottom plate 25 that are close to each other.

[0033] The tension-torsion body 33 forms a flexible transmission path through the rotating wheel 32, which transmits the centrifugal force of the blade 5 to the fixed block 1, shares the bolt load, reduces the direct shear force of the bolt, and avoids metal fatigue. The flexible tension-torsion body can adapt to the small deformation of the blade 5, reduce stress concentration, and the extension rod threaded bolt 31 serves as the rotation axis of the rotating wheel 32. The connecting cap 34 can adjust the tension of the tension-torsion body. By adjusting the thread depth of the connecting cap 34, the load of each blade 5 can be dynamically balanced, and manufacturing errors or wear can be compensated.

[0034] like Figure 1 and Figure 5 As shown, a transmission assembly 4 is provided inside the fixed block 1. The transmission assembly 4 includes a slot 43 opened inside the fixed block 1, a slot 42 is slidably connected to the slot 43, and a transmission rod 41 is fixedly connected to the bottom end of the slot 42.

[0035] The slot 43 and the pin 42 are slidably connected to the fixed block 1 through the slot 43, which allows the axial displacement of the transmission rod 41 and restricts radial rotation, thus achieving a combination of flexible transmission and rigid torque transmission, avoiding the vibration amplification problem of traditional rigid connection.

[0036] Working principle:

[0037] like Figure 1 - Figure 5 As shown:

[0038] In use: First, the blade 5 generates centrifugal force and vibration load during rotation, which in turn drives the top plate 21 and bottom plate 25 fixedly connected to it. The movement of the top plate 21 and bottom plate 25 drives the first bolt 22 and the second bolt 24. The force on the bolts is transmitted to the damping rod 23. The damping rod 23, as an elastic buffer element, deforms and absorbs the energy of the blade 5's flapping and oscillating. At the same time, the double-bolt design distributes the load and reduces the risk of bolt fatigue fracture. Simultaneously, the movement of the blade 5 drives the rotor 32 to rotate. The rotation of the rotor 32 drives the extension rod threaded bolt 31, which in turn drives the extension rod threaded bolt 32 to rotate. 1. The connecting cap 34 drives the tension-torsion body 33, which transmits part of the centrifugal force to the fixed block 1, sharing the bolt load. The flexible tension-torsion body can adapt to the small deformation of the blade 5, reducing stress concentration. After being subjected to the force transmitted by each component, the fixed block 1 generates corresponding movement, driving the internal slot 43. The sliding connection between the slot 43 and the locking post 42 drives the transmission rod 41 to make axial displacement, while restricting its radial rotation, thus realizing the combination of flexible transmission and rigid torque transmission.

[0039] The above description is merely a preferred embodiment of the present utility model and is not intended to limit the present utility model in any other way. Any person skilled in the art may make changes or modifications to the above-disclosed technical content to create equivalent embodiments for application in other fields. However, any simple modifications, equivalent changes, and modifications made to the above embodiments based on the technical essence of the present utility model without departing from the technical solution of the present utility model shall still fall within the protection scope of the technical solution of the present utility model.

Claims

1. A flexible hub for a helicopter, comprising a fixed block (1) inside which a transmission assembly (4) is arranged, characterized in that, It also includes a damping assembly (2), which includes a top plate (21) fixedly connected to both ends of the outer side of the fixed block (1), and a first bolt (22) is threaded inside the top plate (21), and a damping rod (23) is sleeved on the outer side of the first bolt (22). The tension-torsion connection assembly (3) includes a tension-torsion body (33) fixedly connected to both ends inside the fixed block (1), and a rotating wheel (32) is sleeved on the end of the tension-torsion body (33) away from the fixed block (1).

2. A flexible hub for a helicopter as claimed in claim 1, characterised in that: The top plate (21) is internally threaded with a second bolt (24), and the damping rod (23) is fixedly connected to the top plate (21) by the second bolt (24).

3. A flexible hub for a helicopter as defined in claim 1, characterized in that: Both sides of the bottom end of the fixing block (1) are fixedly connected to a base plate (25).

4. A flexible hub for a helicopter as defined in claim 3, characterized in that: The bottom end of the base plate (25) is rotatably connected to a nut (26), and the internal thread of the nut (26) is connected to the outside of the first bolt (22) and the second bolt (24).

5. A flexible hub for a helicopter as defined in claim 1, characterized by: The top plate (21) is internally connected to an extension rod threaded bolt (31), and the outer bottom end of the extension rod threaded bolt (31) is threaded with a connecting cap (34).

6. A flexible rotor hub for helicopters according to claim 1, characterized in that: The inside of the wheel (32) is movably connected to the threaded bolt (31) of the extension rod, and both ends of the outer side of the wheel (32) are rotatably connected to the near end of the top plate (21) and the bottom plate (25).

7. A flexible rotor hub for helicopters according to claim 1, characterized in that: The transmission assembly (4) includes a slot (43) opened inside the fixed block (1), a locking post (42) is slidably connected to the slot (43), and a transmission rod (41) is fixedly connected to the bottom end of the locking post (42).

8. A flexible rotor hub for helicopters according to claim 1, characterized in that: A blade (5) is fixedly connected to the top plate (21) and the bottom plate (25) on the adjacent side.

9. A flexible rotor hub for helicopters according to claim 1, characterized in that: The tension-torsion body (33) uses steel wire, plastic steel wire, Kevlar wire, carbon fiber, glass fiber, graphene composite material, woven alone or in combination.

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