Helicopter rotor head structure

Abstract

The helicopter rotor head structure comprises a propeller hub, a propeller clamp, a bearing and a variable pitch mechanism, the propeller hub is arranged at the top of a rotor main shaft, a connecting shaft is arranged in the propeller hub, the end of the connecting shaft extends out of the propeller hub, the end of the connecting shaft is sleeved with the bearing, and the end, away from blades, of the propeller clamp is sleeved with the bearing and rotationally connected with the connecting shaft; the bearings comprise an angular contact bearing, a thrust roller bearing and a deep groove ball bearing, and the angular contact bearing, the thrust roller bearing and the deep groove ball bearing are sequentially arranged in the length direction of the connecting shaft; and the variable-pitch mechanism is arranged on the rotor wing main shaft in a sleeving manner and is connected with the propeller clamp. The bearing has the technical effects that the angular contact bearing, the thrust roller bearing and the deep groove ball bearing are combined for use, so that the axial and radial bearing capacities of the whole bearing are obviously improved, the bearing is not easy to damage, and the whole service life is longer; and by arranging the variable pitch mechanism, the angle of the paddle can be flexibly adjusted, so that the lift force and the resistance generated by the rotor wing are adjusted.

Description

Technical Field

[0001] The invention relates to the technical field of helicopter parts, and in particular to a helicopter rotor head structure. Background Art

[0002] A fully articulated rotor system is a system of blades connected to a hub that can flap, oscillate and change pitch independently and freely. A fully articulated rotor system allows the rotor pitch to be changed during flight. This system is significantly more complex than a seesaw type rotor head and requires hinges that allow the rotor blades to flap, change pitch and oscillate independently. One of the main advantages of using a fully articulated rotor system is that it can achieve a jump takeoff. To successfully achieve a jump takeoff, the rotor system must have the ability to change the collective pitch, blades with sufficient inertia and a pre-spin system that can reach approximately 150% of the normal flight speed. Rotor blades with very high inertia are desired in helicopter design and are also a necessary condition for autogyro jump takeoff.

[0003] The helicopter hub is the core component that connects the blades and the transmission system. For a fully articulated metal hub, since the thrust bearing in the axial hinge bears the centrifugal force generated by the rotation of the rotor, damage to the thrust bearing will affect the realization of the axial hinge function and seriously affect the safety of the aircraft. Due to its own structural limitations, the existing fully articulated rotor system causes the axial hinge thrust bearing shaft ring and retainer to break easily during use. Therefore, it is necessary to design a new rotor head structure to solve the above technical problems. Summary of the invention

[0004] To this end, the present invention provides a helicopter rotor head structure to solve the above-mentioned problems in the prior art.

[0005] In order to achieve the above object, the present invention provides the following technical solutions:

[0006] According to a first aspect of the present invention, a helicopter rotor head structure comprises a propeller hub, a propeller clamp, a bearing and a pitch change mechanism, wherein the propeller hub is arranged at the top of a rotor main shaft, a connecting shaft is arranged inside the propeller hub, an end of the connecting shaft extends outside the propeller hub, the bearing is sleeved at the end of the connecting shaft, and an end of the propeller clamp facing away from a blade is sleeved outside the bearing and is rotatably connected to the connecting shaft;

[0007] The bearings include angular contact bearings, thrust roller bearings and deep groove ball bearings, wherein the angular contact bearings, thrust roller bearings and deep groove ball bearings are sequentially arranged along the length direction of the connecting shaft, and the deep groove ball bearing is arranged close to the end of the connecting shaft;

[0008] The pitch changing mechanism is sleeved on the rotor main shaft, and the pitch changing mechanism is connected to the propeller clamp.

[0009] Furthermore, the connecting shaft is arranged in a direction perpendicular to the axial direction of the hub, and both ends of the connecting shaft extend to the outside of the hub respectively, and the bearing and the propeller clamp are respectively provided at both ends of the connecting shaft.

[0010] Furthermore, a sleeve is provided at one end of the propeller clamp connected to the connecting shaft, and an annular flange is provided on the inner wall of the sleeve. After installation, the annular flange is located between the angular contact bearing and the thrust roller bearing, and two sides of the annular flange are respectively abutted against the angular contact bearing and the thrust roller bearing.

[0011] Furthermore, it also includes a sealing ring, which is arranged on a side of the deep groove ball bearing away from the thrust roller bearing.

[0012] Furthermore, it also includes a bolt and a gasket, the end of the connecting shaft is provided with a threaded hole, the gasket is arranged on the side of the deep groove ball bearing away from the thrust roller bearing, and the gasket is sleeved on the bolt and abuts against the inner ring of the deep groove ball bearing, and the bolt is threadedly connected to the threaded hole.

[0013] Furthermore, it also includes a retaining ring, which is sleeved on the connecting shaft and abuts against a side of the angular contact bearing that is away from the thrust roller bearing.

[0014] Furthermore, one end of the propeller clamp connected to the propeller blade is provided with two clips, the two clips are symmetrically arranged along the axis of the propeller clamp, and each of the clips is provided with a connecting hole.

[0015] Furthermore, the clip and the sleeve are an integral structure.

[0016] Further, the pitch-changing mechanism comprises a connecting seat and a pitch-changing pull rod, the connecting seat is sleeved on the rotor main shaft, one end of the pitch-changing pull rod is connected to the connecting seat, and the other end of the pitch-changing pull rod is connected to the blade clamp;

[0017] The connecting seat is provided with a driving mechanism, and the driving mechanism is used to drive the connecting seat to move up and down along the rotor main shaft.

[0018] Furthermore, it also includes a rocker arm, which is arranged along the length direction of the propeller clamp, one end of the rocker arm is connected to the propeller clamp, and the other end of the rocker arm is connected to an end of the pitch variable rod away from the connecting seat.

[0019] The present invention has the following advantages: the bearings include angular contact bearings, thrust roller bearings and deep groove ball bearings. By arranging the angular contact bearings, radial loads and axial loads can be borne simultaneously, centrifugal force and bending moment can be better transmitted, and the contact stress level of the bearings can be reduced; by arranging the thrust roller bearings, the axial load mainly being the axial load and the radial combined load can be borne, and the axial load-bearing capacity is significant, which can significantly improve the axial load-bearing capacity; by arranging the deep groove ball bearings, a larger radial load can be borne, which can significantly improve the radial load-bearing capacity; the angular contact bearings, thrust roller bearings and deep groove ball bearings are used in combination, which significantly improves the axial and radial load-bearing capacity of the entire bearing, thereby making it less prone to damage and having a longer overall service life; by arranging the pitch-changing mechanism, the angle of the blade can be flexibly adjusted, thereby adjusting the lift and resistance generated by the rotor. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the implementation methods of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for the implementation methods or the description of the prior art. Obviously, the drawings in the following description are only exemplary, and for ordinary technicians in this field, other implementation drawings can be derived from the provided drawings without creative work.

[0021] The structures, proportions, sizes, etc. illustrated in this specification are only used to match the contents disclosed in the specification so as to facilitate understanding and reading by persons familiar with the technology. They are not used to limit the conditions under which the present invention can be implemented, and therefore have no substantive technical significance. Any structural modification, change in proportion or adjustment of size shall still fall within the scope of the technical contents disclosed in the present invention without affecting the effects and purposes that can be achieved by the present invention.

[0022] Figure 1 An exploded view of a helicopter rotor head structure provided in some embodiments of the present invention.

[0023] Figure 2 A stereoscopic diagram of a helicopter rotor head structure provided for some embodiments of the present invention.

[0024] Figure 3 A partial cross-sectional view of a helicopter rotor head structure provided for some embodiments of the present invention.

[0025] In the figure: 1, rotor main shaft, 2, connecting seat, 3, pitch rod, 4, hub, 5, propeller clamp, 6, clip, 7, connecting shaft, 8, angular contact bearing, 9, thrust roller bearing, 10, deep groove ball bearing, 11, sealing ring, 12, sleeve, 13, connecting hole, 14, gasket, 15, bolt, 16, rocker arm, 17, annular flange, 18, retaining ring. DETAILED DESCRIPTION

[0026] The following is a description of the implementation of the present invention by specific embodiments. People familiar with the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0027] Example 1

[0028] like Figures 1 to 3 As shown, a helicopter rotor head structure in an embodiment of the first aspect of the present invention comprises a hub 4, a blade clamp 5, a bearing and a pitch change mechanism, wherein the hub 4 is arranged at the top of the rotor main shaft 1, a connecting shaft 7 is arranged inside the hub 4, an end of the connecting shaft 7 extends to the outside of the hub 4, a bearing is sleeved at the end of the connecting shaft 7, and an end of the blade clamp 5 away from the blade is sleeved outside the bearing and is rotatably connected to the connecting shaft 7;

[0029] The bearings include an angular contact bearing 8, a thrust roller bearing 9 and a deep groove ball bearing 10. The angular contact bearing 8, the thrust roller bearing 9 and the deep groove ball bearing 10 are sequentially arranged along the length direction of the connecting shaft 7, and the deep groove ball bearing 10 is arranged close to the end of the connecting shaft 7.

[0030] The pitch-changing mechanism is sleeved on the rotor main shaft 1 , and the pitch-changing mechanism is connected to the blade clamp 5 . The pitch-changing mechanism is used to adjust the angle of the blade.

[0031] In this embodiment, it should be noted that the connecting shaft 7 is arranged in a direction perpendicular to the axial direction of the hub 4, and both ends of the connecting shaft 7 extend outside the hub 4 respectively, and bearings and blade clamps 5 are respectively provided at both ends of the connecting shaft 7. During use, the two ends of the connecting shaft 7 are connected to the blades through a blade clamp 5 respectively;

[0032] The specific number of the angular contact bearings 8, thrust roller bearings 9 and deep groove ball bearings 10 can be set to one or more according to actual use requirements. When the number is more than one, the same type of bearings are set as a group.

[0033] The technical effect achieved by this embodiment is as follows: the bearings include angular contact bearings 8, thrust roller bearings 9 and deep groove ball bearings 10. By providing the angular contact bearings 8, they can simultaneously withstand radial loads and axial loads, can better transmit centrifugal force and bending moment, and reduce the contact stress level of the bearings; by providing the thrust roller bearings 9, they can withstand axial loads mainly due to axial loads and combined radial loads, and their axial load-bearing capacity is significant, which can significantly improve the axial load-bearing capacity; by providing the deep groove ball bearings 10, they can withstand larger radial loads, which can significantly improve the radial load-bearing capacity; the combination of the angular contact bearings 8, the thrust roller bearings 9 and the deep groove ball bearings 10 significantly improves the axial and radial load-bearing capacity of the entire bearing, thereby making it less prone to damage and having a longer overall service life; by providing the pitch-changing mechanism, the pitch of the rotor can be flexibly adjusted, thereby adjusting the pulling force of the rotor.

[0034] Example 2

[0035] like Figures 1 to 3 As shown, this embodiment provides another helicopter rotor head structure, and its structure includes all the contents of embodiment 1, and only the different parts are described below.

[0036] In this embodiment, a sleeve 12 is provided at one end of the paddle clamp 5 connected to the connecting shaft 7. The sleeve 12 is provided with a through hole along its axial direction, and the through hole is coaxial with the paddle clamp 5. An annular flange 17 is provided on the inner wall of the sleeve 12. The annular flange 17 and the sleeve are an integral structure, and the annular flange 17 is arranged in a ring along the axis of the sleeve 12. After installation, the annular flange 17 is located between the angular contact bearing 8 and the thrust roller bearing 9, and the two sides of the annular flange 17 are respectively abutted against the angular contact bearing 8 and the thrust roller bearing 9 to form a supporting and limiting effect thereon.

[0037] In this embodiment, it should be noted that a sealing ring 11 is further included. The sealing ring 11 is arranged on the side of the deep groove ball bearing 10 away from the thrust roller bearing 9. The sealing ring 11 is used to prevent the lubricating oil in the bearing from leaking out during use.

[0038] Furthermore, two clips 6 are provided at one end of the paddle clamp 5 connected to the paddle blade. The two clips 6 are symmetrically arranged along the axis of the paddle clamp 5. Each clip 6 is provided with a connecting hole 13. The connecting holes 13 on the two clips 6 are coaxial. The connecting hole 13 is used to install the hinge shaft of the paddle blade, and the clip 6 and the sleeve 12 are an integral structure. During installation, the paddle blade is hinged to the paddle clamp after the hinge shaft passes through the connecting hole 13.

[0039] The technical effect achieved by this embodiment is as follows: the paddle clamp 5 has a simple structure, is easy to manufacture and install, and can form a good assembly effect with the connecting shaft 7 after installation, thereby ensuring smooth transmission of torque.

[0040] Example 3

[0041] like Figures 1 to 3 As shown, this embodiment provides another helicopter rotor head structure, and its structure includes all the contents of Embodiment 2, and only the different parts are described below.

[0042] In this embodiment, a bolt 15 and a gasket 14 are also included. A threaded hole is provided at the end of the connecting shaft 7. The gasket 14 is arranged on the side of the deep groove ball bearing 10 away from the thrust roller bearing 9. The gasket 14 is sleeved on the bolt 15 and abuts against the inner ring of the deep groove ball bearing 10. The bolt 15 is threadedly connected to the threaded hole.

[0043] In the present embodiment, it should be noted that a retaining ring 18 is also included. The retaining ring 18 is sleeved on the connecting shaft 7, and the retaining ring 18 abuts against the side of the angular contact bearing 8 facing away from the thrust roller bearing 9. The retaining ring 18, the annular flange 17, the gasket 14 and the bolt 15 cooperate with each other to position and install the angular contact bearing 8, the thrust roller bearing 9 and the deep groove ball bearing 10, and at the same time realize the installation and fixation of the propeller clamp 5.

[0044] Example 4

[0045] like Figures 1 to 3 As shown, this embodiment provides another helicopter rotor head structure, and its structure includes all the contents of Embodiment 3, and only the different parts are described below.

[0046] In this embodiment, the pitch-changing mechanism includes a connecting seat 2 and a pitch-changing pull rod 3. The connecting seat 2 is sleeved on the rotor main shaft 1. One end of the pitch-changing pull rod 3 is hinged to the connecting seat 2, and the other end of the pitch-changing pull rod 3 is hinged to the blade clamp 5. The length of the pitch-changing pull rod 3 is adjustable.

[0047] A driving mechanism is provided on the connecting seat 2, and the driving mechanism is used to drive the connecting seat 2 to move up and down along the rotor main shaft 1. Specifically, the driving mechanism can be a steering gear.

[0048] In the present embodiment, it should be noted that a rocker arm 16 is further included, and the rocker arm 16 is arranged along the length direction of the propeller clamp 5, one end of the rocker arm 16 is connected to the propeller clamp 5, and the other end of the rocker arm 16 is connected to the end of the pitch-changing rod 3 away from the connecting seat 2; specifically, the rocker arm 16 includes a first arm and a second arm, one end of the first arm is connected to one end of the second arm, and the first arm and the second arm are L-shaped, the first arm and the second arm are an integral structure, the end of the second arm away from the first arm is connected to the propeller clamp 5 by a bolt, the first arm is arranged in a direction parallel to the axis of the propeller clamp 5, and the end of the first arm away from the second arm is hinged to the end of the pitch-changing rod 3 away from the connecting seat 2;

[0049] During use, by adjusting the length of the pitch rod 3 or driving the pitch rod to move by moving the connecting seat 2 up and down, the propeller clamp 5 and the blade can be driven by the rocker arm 16 to rotate a certain angle along the axis of the connecting shaft 7, thereby adjusting the angle of the blade to adjust the lift and resistance generated by the rotor, thereby achieving stable and flexible flight.

[0050] The technical effect achieved by this embodiment is: the pitch-changing mechanism has a simple structure, is easy to use and operate, and can flexibly adjust the angle of the blades, thereby adjusting the lift and resistance generated by the rotor.

[0051] Although the present invention has been described in detail above by general description and specific embodiments, it is obvious to those skilled in the art that some modifications or improvements can be made to the present invention. Therefore, these modifications or improvements made without departing from the spirit of the present invention all belong to the scope of protection claimed by the present invention.

[0052] The terms such as "upper", "lower", "left", "right", "middle", etc. cited in this specification are only for the convenience of description and are not intended to limit the scope of implementation of the present invention. Changes or adjustments to their relative relationships should be regarded as within the scope of implementation of the present invention without substantially changing the technical content.

Claims

1. A helicopter rotor head structure, characterized in that: The invention comprises a propeller hub (4), a propeller clamp (5), a bearing and a pitch-changing mechanism, wherein the propeller hub (4) is arranged at the top of the rotor main shaft (1), a connecting shaft (7) is arranged inside the propeller hub (4), an end of the connecting shaft (7) extends outside the propeller hub (4), the bearing is sleeved on the end of the connecting shaft (7), and an end of the propeller clamp (5) away from the propeller blade is sleeved outside the bearing and is rotatably connected to the connecting shaft (7); The bearing comprises an angular contact bearing (8), a thrust roller bearing (9) and a deep groove ball bearing (10); the angular contact bearing (8), the thrust roller bearing (9) and the deep groove ball bearing (10) are arranged in sequence along the length direction of the connecting shaft (7); the deep groove ball bearing (10) is arranged close to the end of the connecting shaft (7); The pitch changing mechanism is sleeved on the rotor main shaft (1), and the pitch changing mechanism is connected to the propeller clamp (5).

2. A helicopter rotor head structure according to claim 1, characterized in that: The connecting shaft (7) is arranged in a direction perpendicular to the axial direction of the propeller hub (4), and both ends of the connecting shaft (7) extend outside the propeller hub (4) respectively. The bearing and the propeller clamp (5) are respectively provided at both ends of the connecting shaft (7).

3. A helicopter rotor head structure according to claim 1, characterized in that: A sleeve (12) is provided at one end of the paddle clamp (5) connected to the connecting shaft (7), and an annular ridge (17) is provided on the inner wall of the sleeve (12). After installation, the annular ridge (17) is located between the angular contact bearing (8) and the thrust roller bearing (9), and two sides of the annular ridge (17) are respectively in contact with the angular contact bearing (8) and the thrust roller bearing (9).

4. A helicopter rotor head structure according to claim 3, characterized in that: It also includes a sealing ring (11), which is arranged on a side of the deep groove ball bearing (10) facing away from the thrust roller bearing (9).

5. A helicopter rotor head structure according to claim 3, characterized in that: It also includes a bolt (15) and a gasket (14), wherein a threaded hole is provided at the end of the connecting shaft (7), and the gasket (14) is arranged on the side of the deep groove ball bearing (10) away from the thrust roller bearing (9), and the gasket (14) is sleeved on the bolt (15) and abuts against the inner ring of the deep groove ball bearing (10), and the bolt (15) is threadedly connected to the threaded hole.

6. A helicopter rotor head structure according to claim 3, characterized in that: It also comprises a retaining ring (18), wherein the retaining ring (18) is sleeved on the connecting shaft (7), and the retaining ring (18) abuts against a side of the angular contact bearing (8) facing away from the thrust roller bearing (9).

7. A helicopter rotor head structure according to claim 3, characterized in that: One end of the paddle clamp (5) connected to the paddle blade is provided with two clips (6), the two clips (6) are symmetrically arranged along the axis of the paddle clamp (5), and each of the clips (6) is provided with a connecting hole (13).

8. A helicopter rotor head structure according to claim 7, characterized in that: The clip (6) and the sleeve (12) are an integral structure.

9. The helicopter rotor head structure according to claim 1, characterized in that: The pitch-changing mechanism comprises a connecting seat (2) and a pitch-changing pull rod (3); the connecting seat (2) is sleeved on the rotor main shaft (1); one end of the pitch-changing pull rod (3) is connected to the connecting seat (2); and the other end of the pitch-changing pull rod (3) is connected to the propeller clamp (5); The connecting seat (2) is provided with a driving mechanism, and the driving mechanism is used to drive the connecting seat (2) to move up and down along the rotor main shaft (1).

10. A helicopter rotor head structure according to claim 9, characterized in that: It also includes a rocker arm (16), which is arranged along the length direction of the propeller clamp (5), one end of the rocker arm (16) is connected to the propeller clamp (5), and the other end of the rocker arm (16) is connected to an end of the pitch-changing rod (3) away from the connecting seat (2).

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