A top rotor handling assembly and top rotor

Abstract

The application discloses an upper rotor control assembly and an upper rotor, and belongs to the technical field of helicopters, and solves the problems of complex control structure, more movement pairs leading to large gap, and too many rod structures leading to stiffness reduction of coaxial helicopters. The upper rotor control assembly is located below the upper rotor and the lower rotor of the helicopter, and controls the upper rotor from below the upper rotor. The upper rotor control assembly comprises a stationary disc, a movable disc, a connecting rod assembly and a connecting shaft. The connecting shaft is a hollow structure, one end of the connecting rod assembly is rotationally connected with the movable disc, and the other end of the connecting rod assembly is rotationally connected with the paddle clamp of the upper rotor through the connecting shaft. The stationary disc is rotationally connected with the movable disc, the stationary disc comprises an x-axis rod and a y-axis rod which is fixedly connected with the x-axis rod perpendicularly, and the movable disc moves along the x-axis and the y-axis of the upper rotor to drive the movable disc to tilt and realize cyclic pitch change of the upper rotor. The upper rotor control assembly and the upper rotor can be used for helicopters.

Description

Technical Field

[0001] This invention belongs to the field of helicopter technology, and particularly relates to an upper rotor control assembly and an upper rotor. Background Technology

[0002] Coaxial helicopters have advantages such as high hovering efficiency and small size.

[0003] Currently, existing coaxial helicopter rotor control mainly adopts off-axis control, see [link to relevant documentation]. Figure 1 However, it has the following drawbacks: complex structure, large number of parts, heavy weight, and high cost; many kinematic pairs, resulting in large clearances, which affect the aircraft's handling quality; too many rod structures, which lead to a decrease in stiffness, affecting rotor dynamics and handling quality. Summary of the Invention

[0004] Based on the above analysis, the present invention aims to provide an upper rotor control assembly and an upper rotor, which solves the problems of complex control structure, large clearance due to numerous kinematic pairs, and reduced stiffness due to excessive rod structures in the prior art for coaxial helicopter upper rotors.

[0005] The objective of this invention is mainly achieved through the following technical solutions:

[0006] This invention provides an upper rotor control assembly, located below the upper and lower rotors of a helicopter, allowing for control of the upper rotor from below. The upper rotor control assembly includes a fixed plate, a moving plate, a linkage assembly, and a connecting shaft. The connecting shaft has a hollow structure; one end of the linkage assembly is rotatably connected to the moving plate, and the other end of the linkage assembly passes through the connecting shaft and is rotatably connected to the rotor clamp of the upper rotor. The fixed plate is rotatably connected to the moving plate, and the fixed plate includes an x-axis rod and a y-axis rod perpendicularly and fixedly connected to the x-axis rod. The moving plate moves along the x-axis and y-axis of the upper rotor, driving the moving plate to tilt and achieve periodic pitch changes of the upper rotor.

[0007] Furthermore, it also includes an x-axis servo and a y-axis servo, with the x-axis servo connected to the x-axis rod and the y-axis servo connected to the y-axis rod.

[0008] Furthermore, the x-axis servo is connected to the x-axis rod via a rod end bearing, and the y-axis servo is connected to the y-axis rod via a rod end bearing.

[0009] Furthermore, the linkage assembly includes a rod body and an L-shaped component; the L-shaped component includes a horizontal rod and a vertical rod connected to the horizontal rod, the end of the horizontal rod away from the vertical rod is connected to the rod body, and the end of the vertical rod away from the horizontal rod is rotatably connected to the swashplate via a rod end bearing.

[0010] Furthermore, it also includes a collective pitch fixed ring and a collective pitch moving ring, with the collective pitch fixed ring and the collective pitch moving ring rotatably connected, and the collective pitch moving ring connected to the moving disk.

[0011] Furthermore, the collective pitch fixed ring and the collective pitch moving ring are rotatably connected by a spherical bearing.

[0012] Furthermore, it also includes a z-axis servo, a connector, and a support. The servo connection end of the connector is rotatably connected to the z-axis servo, the fixed ring connection end of the connector is rotatably connected to the collective pitch fixed ring, and the support is rotatably connected to any position between the two ends of the connector.

[0013] Furthermore, the servo connection end of the connector is a closed end, while the fixed ring connection end of the connector is an open end.

[0014] Furthermore, it also includes a horn-shaped component, the upper end face of which is fixedly connected to the collective pitch ring, and the lower end face of which is rotatably connected to the tilting disk.

[0015] The present invention also provides an upper rotor, including the above-described upper rotor control assembly.

[0016] Compared with the prior art, the present invention can achieve at least one of the following beneficial effects:

[0017] A) The rotor control assembly provided by this invention places the linkage assembly within the connecting shaft of a hollow structure, employing in-shaft control instead of traditional out-of-shaft control. This solution is simple and clear, greatly simplifying the structure while meeting basic design requirements and functions, effectively reducing the types and number of parts, and lightening the weight of the rotor control system. Furthermore, through improvements to the fixed-plate structure, the moving plate can be tilted at any angle within a threshold range simply by moving along the x and y axes, resulting in a simple structure.

[0018] B) The upper rotor control assembly provided by the present invention drives the collective pitch fixed ring to move along the z-axis of the upper rotor, and the linkage assembly, moving disk and fixed disk move upward as a whole. The blade angle of all blades increases or decreases at the same time, so that the overall lift of the helicopter upper rotor increases or decreases, thereby enabling the collective pitch of the upper rotor to change.

[0019] Other features and advantages of the invention will be set forth in the description which follows, and will be apparent in part from the description, or may be learned by practicing the invention. The objects and other advantages of the invention may be realized and obtained by means of the structures particularly pointed out in the written description and the accompanying drawings. Attached Figure Description

[0020] The accompanying drawings are for illustrative purposes only and are not intended to limit the invention. Throughout the drawings, the same reference numerals denote the same parts.

[0021] Figure 1 This is a schematic diagram of the structure of an upper rotor control assembly in the prior art;

[0022] Figure 2This is a schematic diagram of the upper rotor control assembly provided in Embodiment 1 of the present invention;

[0023] Figure 3a This is a schematic diagram illustrating the principle of the leftward movement of the fixed plate in the upper rotor control assembly provided in Embodiment 1 of the present invention;

[0024] Figure 3b This is a schematic diagram illustrating the principle of the fixed plate moving to the right in the upper rotor control assembly provided in Embodiment 1 of the present invention;

[0025] Figure 4a This is a schematic diagram illustrating the principle of the collective pitch plate moving downwards in the upper rotor control assembly provided in Embodiment 1 of the present invention;

[0026] Figure 4b This is a schematic diagram illustrating the principle of the collective pitch plate moving upward in the upper rotor control assembly provided in Embodiment 1 of the present invention;

[0027] Figure 5 This is a schematic diagram of the connection between the rotor hub and the rotor clip in the upper rotor according to Embodiment 2 of the present invention;

[0028] Figure 6 This is a schematic diagram of the structure of the first elastic bearing in the upper rotor provided in Embodiment 2 of the present invention;

[0029] Figure 7 This is a cross-sectional view of the first elastic bearing in the upper rotor provided in Embodiment 2 of the present invention;

[0030] Figure 8 This is a schematic diagram of the structure of the second elastic bearing in the upper rotor provided in Embodiment 2 of the present invention;

[0031] Figure 9 This is a cross-sectional view of the second elastic bearing in the upper rotor provided in Embodiment 2 of the present invention;

[0032] Figure 10 This is a schematic diagram of the main rotor counterweight bolt in the upper rotor provided in Embodiment 3 of the present invention;

[0033] Figure 11 This is a schematic diagram of the spanwise counterweight assembly for the upper rotor provided in Embodiment 4 of the present invention;

[0034] Figure 12 This is a cross-sectional view of the spanwise counterweight assembly of the upper rotor provided in Embodiment 4 of the present invention;

[0035] Figure 13 This is a schematic diagram of the structure of the middle support column in the upper rotor provided in Embodiment 4 of the present invention.

[0036] Figure label:

[0037] 1-Blade; 2-Blade clamp; 3-Main blade bolt; 4-Dynamic balance weight; 5-Pressure nut; 6-Cocker pin; 7-Screw; 8-Central component; 9-First elastic bearing; 91-Internal spline; 92-Elastic layer; 93-Rigid layer; 94-Connecting cylinder; 95-Connecting ring; 96-External spline; 97-Inner connecting layer; 10-Second elastic bearing; 101-Rigid disc; 102-Elastic disc; 103-Inner layer; 104-Elastic cylinder; 105-Rigid cylinder; 06-Outer layer; 107-Connecting protrusion; 108-Inner layer spline protrusion; 109-Outer layer spline protrusion; 11-Safety pin; 12-First limit block; 13-Blade bolt; 14-Intermediate support; 15-Elastic element; 16-Spreading counterweight; 17-Fixed plate; 18-Moving plate; 19-Linkage assembly; 20-Collective pitch fixed ring; 21-Collective pitch moving ring; 22-Connector; 23-Bell-shaped element; 24-Universal joint; 25-X-axis servo; 26-Y-axis servo. Detailed Implementation

[0038] Preferred embodiments of the present invention will now be described in detail with reference to the accompanying drawings, which form part of the present invention and, together with the embodiments of the present invention, serve to illustrate the principles of the present invention.

[0039] Example 1

[0040] This embodiment provides an upper rotor control assembly; see [link / reference] Figures 2 to 4b Located below the upper and lower rotors of the helicopter, the upper rotor is operated from below. The upper rotor control assembly includes a fixed plate 17, a moving plate 18, a linkage assembly 19, and a connecting shaft. The connecting shaft is a hollow structure, with the rotor hubs of the upper and lower rotors fixedly connected to the outer wall of the connecting shaft, respectively. One end of the linkage assembly 19 is rotatably connected to the moving plate 18, and the other end of the linkage assembly 19 passes through the connecting shaft and is rotatably connected to the rotor clip of the upper rotor. The fixed plate 17 is rotatably connected to the moving plate 18. The fixed plate 17 includes an x-axis rod and a y-axis rod that is perpendicularly fixed to the x-axis rod. The moving plate 18 moves along the x-axis and y-axis of the upper rotor, driving the moving plate 18 to tilt and achieve periodic pitch changes of the upper rotor.

[0041] See the principle of periodic pitch variation. Figures 3a to 3bWhen the fixed plate 17 moves to the left, the moving plate 18 can rotate along the axial plane of the fixed plate 17. The fixed plate 17 drives the moving plate 18 to tilt as a whole and rotate clockwise. The left side of the moving plate 18 rises and the right side falls, which in turn drives the connecting rod corresponding to the left side of the moving plate 18 to rise and the connecting rod corresponding to the right side of the moving plate 18 to fall. This makes the blade angles at different positions inconsistent, resulting in different lift at different blade angles. This enables the helicopter to achieve pitch and roll attitude control and cyclic pitch control of the upper rotor. Conversely, the same applies. It should be noted that by driving the fixed plate 17 to move simultaneously along the x-axis and y-axis, the fixed plate 17 can be located at any position in the xy-plane, thereby driving the moving plate 18 to tilt at any angle within the threshold range.

[0042] It should be noted that the axial plane refers to the plane passing through the axis.

[0043] Compared with existing technologies, the upper rotor control assembly provided in this embodiment places the linkage assembly 19 inside the connecting shaft of the hollow structure, and adopts in-shaft control instead of traditional external shaft control. The solution is simple and clear, greatly simplifying the structure while meeting basic design requirements and functions, effectively reducing the types and number of parts, and reducing the weight of the rotor control system. At the same time, through the improvement of the structure of the fixed plate 17, the moving plate 18 can be tilted at any angle within the threshold range by moving only the x-axis and y-axis, and the structure is simple.

[0044] Understandably, in order to drive the fixed plate 17 to move along the x-axis and y-axis of the upper rotor, the aforementioned upper rotor control assembly also includes an x-axis servo 25 and a y-axis servo 26. The x-axis servo 25 is connected to the x-axis rod via a rod end bearing, and the y-axis servo 26 is connected to the y-axis rod via a rod end bearing. The x-axis servo 25 drives the x-axis rod to move along the x-axis of the upper rotor, and the y-axis servo 26 drives the y-axis rod to move along the y-axis of the upper rotor.

[0045] Specifically, the structure of the linkage assembly 19 includes a rod body and an L-shaped component. The L-shaped component is an inverted L-shape and includes a horizontal rod and a vertical rod connected to the horizontal rod. The end of the horizontal rod away from the vertical rod is connected to the rod body, and the end of the vertical rod away from the horizontal rod is rotatably connected to the tilting plate through a rod end bearing.

[0046] To achieve collective pitch variation of the upper rotor, the aforementioned upper rotor control assembly also includes a fixed collective pitch ring 20 and a moving collective pitch ring 21. The fixed collective pitch ring 20 and the moving collective pitch ring 21 are rotatably connected via a spherical bearing, and the moving collective pitch ring 21 is fixedly connected to the moving disk 18. It should be noted that the fixed collective pitch ring 20 does not rotate, while the moving collective pitch ring 21 can rotate along its axial plane and around its axis. For the principle of collective pitch variation, please refer to [link to relevant documentation]. Figures 4a to 4bThe collective pitch fixed ring 20 moves along the z-axis of the upper rotor, driving the collective pitch moving ring 21 to move along the z-axis of the upper rotor. The connecting rod assembly 19, the moving plate 18, and the fixed plate 17 move upward as a whole, and the blade angles of all blades increase or decrease simultaneously, thereby increasing or decreasing the overall lift of the helicopter upper rotor, thus enabling the collective pitch of the upper rotor to change.

[0047] Similarly, in order to drive the collective pitch fixed ring 20 and the collective pitch moving ring 21 to move along the z-axis of the upper rotor, the above-mentioned upper rotor control assembly also includes a z-axis servo, a connector 22 and a support. The servo connection end of the connector 22 (one end of the connector 22) is rotatably connected to the z-axis servo, the fixed ring connection end of the connector 22 (the other end of the connector 22) is rotatably connected to the collective pitch fixed ring 20, and the support is rotatably connected to any position between the two ends of the connector 22, so that the connector 22 and the support form a seesaw-like structure. When the z-axis servo drives the servo connection end of the connector 22 to move downward, the fixed ring connection end of the connector 22 moves upward, thereby enabling the collective pitch fixed ring 20 and the collective pitch moving ring 21 to move along the z-axis of the upper rotor.

[0048] For the structure of connector 22, for example, it is a fork-shaped part. The servo connection end of connector 22 is a closed end. The servo connection end is connected to the output shaft of the servo through the rod end bearing. The fixed ring connection end of connector 22 is an open end. A U-shaped part is fixed on the fixed ring. The fixed ring connection end is inserted into the U-shaped part and is rotatably connected to the U-shaped part through the rotating shaft.

[0049] In order to achieve the connection between the collective pitch disk 18 and the swashplate, the above-mentioned upper rotor control assembly also includes a horn-shaped component 23. The upper end face of the horn-shaped component 23 is fixedly connected to the collective pitch ring 21, and the lower end face of the horn-shaped component 23 is rotatably connected to the swashplate through a universal joint.

[0050] Specifically, the structure of the horn-shaped component 23 includes an upper ring, a tilting rod, and a lower plate. One end of the tilting rod is fixedly connected to the upper ring, and the other end of the tilting rod is fixedly connected to the lower plate. The upper ring is fixedly connected to the total torque ring 21, and the lower plate is rotatably connected to the tilting plate through a universal joint 24.

[0051] To prevent the lower end plate from interfering with the movement of the link assembly 19, a through hole is provided on the lower end plate, through which the link assembly 19 (e.g., the vertical rod) passes.

[0052] The specific implementation process of this embodiment is as follows (taking the leftward movement of the fixed plate 17 and the upward movement of the collective pitch ring as examples only):

[0053] Periodic pitch change: The output shaft of the X-axis servo 25 retracts, driving the X-axis rod to move to the left. At this time, the Y-axis rod rotates at a certain angle relative to the output shaft of the Y-axis servo 26 through the rod end bearing. The fixed plate 17 moves to the left as a whole. The end of the swashplate connected to the moving plate 18 moves to the left under the drive of the fixed plate 17. However, since the radial movement of the linkage assembly 19 is limited by the horn-shaped part 23, the end of the moving plate 18 away from the fixed plate 17 cannot move to the left under the limitation of the linkage assembly 19, thus causing the end of the swashplate away from the fixed plate 17 to rotate clockwise; and the tilt... The vertical lever corresponding to the left side of the swashplate moves upward, sequentially causing the corresponding horizontal lever and the lower end of the lever to move upward. The upper end of the lever connects to one side of the rotor clamp. The upward movement of the lever causes the rotor clamp to rotate at a certain angle, thereby changing the angle of the rotor blade. Similarly, the vertical lever corresponding to the right side of the swashplate moves downward, sequentially causing the corresponding horizontal lever and the lower end of the lever to move downward. The upper end of the lever connects to one side of the rotor clamp. The downward movement of the lever causes the rotor clamp to rotate at a certain angle, thereby changing the angle of the rotor blade. This overall process achieves pitch and roll attitude control of the helicopter and cyclic pitch control of the upper rotor.

[0054] Collective pitch change: The output shaft movement of the Z-axis servo causes the servo connection end of connector 22 to move downwards, the support member supports the middle part of connector 22, and correspondingly, the moving ring connection end of connector 22 moves upwards; since the fixed ring connection end of connector 22 is connected to the collective pitch fixed ring 20, the fixed ring connection end can drive the collective pitch fixed ring 20 to move upwards; the collective pitch moving ring 21 and the collective pitch fixed ring 20 are rotatably connected by a spherical bearing, which allows the collective pitch moving ring 21 to rotate about its axis and along its axial plane, but limits the axial movement of the collective pitch moving ring 21. When the collective pitch fixed ring 20 moves upwards, it can drive the collective pitch moving ring 21 to move upwards; then, Since the collective pitch ring 21 is connected to the moving plate 18 via a universal joint, and the moving plate 18 is connected to the fixed plate 17 via a universal joint, the x-axis rod of the fixed plate 17 is connected to the x-axis servo 25 via a rod end bearing, and the y-axis rod of the fixed plate 17 is connected to the y-axis servo 26 via a rod end bearing, the upward movement of the collective pitch ring 21 can sequentially drive the moving plate 18, the fixed plate 17, the output end of the x-axis servo 25, and the output end of the y-axis servo 26 to move upward as a whole. All the vertical rods, horizontal rods, and rods will also move upward as a whole, thereby driving the rotor clip to rotate as a whole. The rotor blade angle increases simultaneously, and the overall lift of the helicopter's upper rotor increases, thus enabling the collective pitch change of the upper rotor.

[0055] Example 2

[0056] This embodiment provides an upper rotor, see [link / reference] Figures 5 to 9 It includes a rotor hub, a rotor clip, and the upper rotor control assembly provided in Embodiment 1. The rotor clip is connected to the rotor hub and the linkage assembly, respectively.

[0057] Compared with the prior art, the beneficial effects of the upper rotor provided in this embodiment are basically the same as those of the upper rotor control assembly provided in Embodiment 1, and will not be described in detail here.

[0058] Specifically, the rotor hub includes a first elastic bearing 9, a second elastic bearing 10, and a central component 8. The central component 8 is connected to the helicopter's rotor clip 2 via the second elastic bearing 10 and the first elastic bearing 9. That is, from the inside out, the rotor clip 2, the first elastic bearing 9, and the central component 8 are sequentially fitted together. The central component 8 is located on the outer wall of the first elastic bearing 9, and the rotor clip 2 is located on the inner wall of the first elastic bearing 9. The rotor clip 2, the second elastic bearing 10, and the central component 8 are sequentially fitted together. The central component 8 is located on the outer wall of the second elastic bearing 10, and the rotor clip 2 is located on the inner wall of the second elastic bearing 10. The first elastic bearing 9 is a cylindrical elastic bearing used to withstand the flapping force and lift generated by the helicopter rotor blade 1. The second elastic bearing 10 is a flange-type elastic bearing used to withstand the flapping force, lift, and centrifugal force generated by the rotor blade 1. In this way, by replacing the original metal bearing with the first elastic bearing 9 (i.e., cylindrical elastic bearing) and the second elastic bearing 10 (i.e., flange elastic bearing), the structure of the propeller hub based on elastic bearings can be greatly simplified, the types and number of parts can be effectively reduced, no special sealing structure is required, the machining precision of parts can be reduced, and the life of the first elastic bearing 9 is much longer than that of the metal bearing. It can effectively solve the problems of complex metal bearing hooks, high requirements for sealing, assembly, lubrication, precision and working environment, and wear, indentation and gaps that will occur after long-term operation when using metal bearings for propeller hubs based on elastic bearings.

[0059] The structures of the first elastic bearing 9 and the second elastic bearing 10 are described in detail below:

[0060] Specifically, the structure of the first elastic bearing 9 includes, from the outside to the inside, an outer connecting layer, a sleeve layer, and an inner connecting layer 97 that are sequentially sleeved together. The outer connecting layer is fixedly connected to the central member 8, the inner connecting layer 97 is fixedly connected to the paddle clamp 2, and the sleeve layer includes an elastic layer 92 (e.g., a rubber layer) and a rigid layer 93 (e.g., a metal layer) that are alternately sleeved together in the radial direction.

[0061] In practical applications, the sleeve layer bears the flapping force and oscillation lift generated by the blade 1 through the relative circumferential rotation between the inner and outer walls of the elastic layer 92. However, it is worth noting that the relative circumferential rotation between the inner and outer walls of the elastic layer 92 causes the material of the elastic layer 92 to be subjected to shear force. Thus, once the relative circumferential rotation between the inner and outer walls of the elastic layer 92 exceeds the maximum shear force that the material of the elastic layer 92 can withstand, the material of the elastic layer 92 will be damaged, which will lead to the overall damage of the first elastic bearing 9. Therefore, it is necessary to appropriately limit the relative circumferential rotation between the inner and outer walls of the elastic layer 92 to avoid damaging the elastic layer 92. For example, a limiting spline assembly is provided between two rigid layers 93 adjacent to one of the elastic layers 92. The limiting spline assembly is used to limit the relative circumferential rotation between the inner and outer walls of the elastic layer 92.

[0062] Specifically, a rigid layer 93 adjacent to the inner wall of the elastic layer 92 is defined as the first rigid layer 93, and a rigid layer 93 adjacent to the outer wall of the elastic layer 92 is defined as the second rigid layer 93. The outer wall of the first rigid layer 93 has multiple first spline protrusions along its circumference, with a first spline groove between two adjacent first spline protrusions. The inner wall of the second rigid layer 93 has multiple second spline protrusions along its circumference, with a second spline groove between two adjacent second spline protrusions. The first spline protrusions are inserted into the second spline grooves, and the sidewalls of the first spline protrusions and the second spline grooves have a first gap; the second spline protrusions are inserted into the second spline grooves, and the sidewalls of the second spline protrusions and the first spline grooves have a second gap. It should be noted that no elastic layer 92 is disposed in the first gap or the second gap. In this way, the first spline protrusion can only move in the second spline groove, and the second spline protrusion can only move in the first spline groove. That is to say, the relative circumferential rotation distance between the inner wall and the outer wall of the elastic layer 92 is the minimum value of the first gap and the second gap. This can appropriately limit the relative circumferential rotation between the inner wall and the outer wall of the elastic layer 92, and can basically prevent the elastic layer 92 from being damaged, thereby improving the safety of the above-mentioned propeller hub based on the elastic bearing.

[0063] To ensure a stable connection between the first elastic bearing 9 and the central component 8, the outer connecting layer specifically includes a connecting cylinder 94 and a connecting ring 95 located at one end of the connecting cylinder 94 and fixedly connected to it. In practical applications, the connecting cylinder 94 and the connecting ring 95 can be integrally formed, with both the outer wall of the connecting cylinder 94 and the side wall of the connecting ring 95 fixedly connected to the central component 8. This dual connection, where both the connecting cylinder 94 and the connecting ring 95 are fixedly connected to the central component 8, ensures a stable connection between the first elastic bearing 9 and the central component 8. Furthermore, it should be noted that the connecting ring 95 also restricts the axial movement of the first elastic bearing 9, thus enabling it to bear a portion of the centrifugal force generated by the blade 1.

[0064] It should be noted that, in order to ensure that the first elastic bearing 9 has sufficient mechanical strength, both the inner connecting layer 97 and the outer connecting layer are rigid components.

[0065] For example, the inner connecting layer 97 and the propeller clip 2, as well as the outer connecting layer and the central member 8, can be detachably and fixedly connected by a spline structure. Specifically, the inner wall of the inner connecting layer 97 is provided with an inner spline 91 protrusion, which cooperates with the spline groove of the propeller clip 2 provided on the propeller clip 2; the outer wall of the outer connecting layer is provided with an outer spline 96 protrusion, which cooperates with the spline groove of the central member 8 provided on the central member 8.

[0066] It should be noted that, in order to facilitate the connection between the sheath and the inner connecting layer 97 and the outer connecting layer, both the inner end face and the outer end face of the sheath are elastic layers 92.

[0067] In practical applications, the number of rigid layers 93 is odd, the number of elastic layers 92 is even, and the difference between the number of elastic layers 92 and rigid layers 93 is 1.

[0068] For example, the number of rigid layers 93 is 1 to 3, and the number of elastic layers 92 is 2 to 4. That is, if the number of rigid layers 93 is 1, then the number of elastic layers 92 is 2, and the nested layers include elastic layers 92, rigid layers 93 and elastic layers 92 nested together in sequence; if the number of rigid layers 93 is 3, then the number of elastic layers 92 is 4, and the nested layers include elastic layers 92, rigid layers 93, elastic layers 92, rigid layers 93, elastic layers 92, rigid layers 93 and elastic layers 92 nested together in sequence.

[0069] It is worth noting that in the first elastic bearing 9, the elastic layer 92 is mainly used to bear the flapping force and oscillation lift generated by the blade 1, and the rigid layer 93 is mainly used to ensure the mechanical strength of the first elastic bearing 9. The rigid layer 93 only needs to ensure the mechanical strength. Therefore, the radial thickness of the rigid layer 93 is less than the radial thickness of the elastic layer 92.

[0070] To ensure that the first elastic bearing 9 has sufficient mechanical properties, the radial thickness of the first elastic bearing 9 is 8 to 40 mm, such as 8 mm, 16 mm, 25 mm, 36 mm or 40 mm.

[0071] In order to achieve a detachable and fixed connection between the outer wall of the first elastic bearing 9 and the central component 8, for example, the outer wall of the first elastic bearing 9 is provided with an external spline 96, and the inner wall of the central component 8 is provided with a central spline. The external spline 96 and the central spline cooperate with each other to achieve a detachable and fixed connection between the outer wall of the first elastic bearing 9 and the central component 8.

[0072] Similarly, in order to achieve a detachable and fixed connection between the inner wall of the first elastic bearing 9 and the propeller clamp 2, for example, the inner wall of the first elastic bearing 9 is provided with an inner spline 91, and the outer wall of the propeller clamp 2 is provided with a propeller clamp 2 spline. The inner spline 91 and the propeller clamp 2 spline cooperate with each other to achieve a detachable and fixed connection between the inner wall of the first elastic bearing 9 and the propeller clamp 2.

[0073] Specifically, the structure of the second elastic bearing 10 includes a flange and a boss connected to the flange, both coaxially arranged. The flange includes rigid discs 101 (e.g., metal discs) and elastic discs 102 (e.g., rubber discs) that are alternately stacked and fixedly connected along the axial direction. In implementation, the side of the flange and the outer end face of the boss are fixedly connected to the central member 8, and the inner end face of the boss is fixedly connected to the paddle clamp 2. The flange can withstand centrifugal force. By using the alternating stacking of rigid discs 101 and elastic discs 102 as the flange, the flange has a certain elastic deformation, thereby enabling the variable pitch movement of the elastic bearing. It should be noted that in practical applications, the variable pitch movement of the paddle clamp 2 is a small-angle periodic reciprocating rotation; therefore, the elastic bearing can meet the actual requirements. At the same time, the sealing performance of the elastic disc 102 is usually greater than that of the rigid disc 101. The elastically deformable flange itself has a certain sealing performance; therefore, excessive sealing design is unnecessary, effectively reducing the number of parts in the elastic bearing and improving its environmental adaptability. Furthermore, since the weight of the elastic disc 102 is typically less than that of the rigid disc 101, the inclusion of the elastic disc 102 effectively reduces the overall weight of the elastic bearing. The inclusion of the elastic disc 102 also reduces the precision requirements for parts machining, lowers processing costs, and improves the product yield.

[0074] To facilitate the connection between the flange and the central component 8, a connecting protrusion 107 is provided at the end of the flange away from the boss. A connecting hole is provided on the connecting protrusion 107, and the central component 8 is connected to the flange through the connecting protrusion 107.

[0075] For example, there are two connecting protrusions 107, which are arranged symmetrically with respect to the axis of the flange, and each connecting protrusion 107 has three connecting holes.

[0076] It should be noted that, in order to ensure that the flange has sufficient mechanical strength, both end faces of the flange are rigid plates 101, and the thickness of the rigid plates 101 at both ends is greater than the thickness of the rigid plates 101 at the inside.

[0077] Accordingly, in practical applications, the number of rigid disks 101 is odd, the number of elastic disks 102 is even, and the difference between the number of rigid disks 101 and elastic disks 102 is 1.

[0078] For example, the number of rigid discs 101 is 5 to 7 layers, and the number of elastic discs 102 is 4 to 6 layers. That is, if the number of rigid discs 101 is 7 layers, then the number of elastic discs 102 is 6 layers. In this case, the flange is formed by stacking rigid discs 101, elastic discs 102, rigid discs 101, elastic discs 102, rigid discs 101, elastic discs 102, rigid discs 101, elastic discs 102, rigid discs 101, elastic discs 102, rigid discs 101, elastic discs 102, rigid discs 101, elastic discs 102, rigid discs 101, elastic discs 102, rigid discs 101, elastic discs 102, rigid discs 101, elastic discs 102, rigid discs 101, elastic discs 102, rigid discs 101, elastic discs 102, rigid discs 101, elastic discs 102, rigid discs 101, elastic discs 102, rigid discs 101, elastic discs 102, rigid discs 101, elastic discs 102, rigid discs 101, elastic discs 102, rigid discs 101.

[0079] To ensure that the flange has sufficient mechanical properties, the axial thickness of the above flange is 10 to 50 mm, such as 10 mm, 18 mm, 26 mm, 36 mm, 45 mm or 50 mm.

[0080] To withstand sufficient flapping and oscillating lift forces, the boss structure, specifically, comprises, from the outside in, a sequentially nested outer layer 106, a stacked layer, and an inner layer 103. The outer layer 106 is fixedly connected to the central component 8, and the inner layer 103 is fixedly connected to the paddle clamp 2. The stacked layer includes radially alternating elastic cylinders 104 (e.g., rubber cylinders) and rigid cylinders 105 (e.g., metal cylinders). Using an elastic boss allows it to withstand sufficient flapping and oscillating lift forces, enabling the boss to also exhibit a certain degree of elastic deformation, reducing the machining precision required for the boss, and improving its sealing performance.

[0081] It should be noted that, in order to ensure that the boss has sufficient mechanical strength, both the inner layer 103 and the outer layer 106 are rigid components.

[0082] For example, the inner layer 103 and the blade 1, as well as the outer layer 106 and the central component 8, can be detachably and fixedly connected by a spline structure. Specifically, the inner wall of the inner layer 103 is provided with an inner spline protrusion 108, which cooperates with the spline groove of the blade clamp 2 provided on the blade clamp 2; the outer wall of the outer layer 106 is provided with an outer spline protrusion 5 109, which cooperates with the spline groove of the blade hub provided on the central component.

[0083] It should be noted that, in order to facilitate the connection between the laminate and the inner layer 103 and the outer layer 106, both the inner and outer end faces of the laminate are elastic cylinders 104.

[0084] In practical applications, the number of rigid cylinders 105 is odd, the number of elastic cylinders 104 is even, and the difference between the number of rigid cylinders 105 and elastic cylinders 104 is 1.

[0085] For example, the number of rigid cylinders 105 is 3 to 5 layers, and the number of elastic cylinders 104 is 2 to 4 layers. That is, if the number of rigid cylinders 105 is 5 layers, then the number of elastic cylinders 104 is 4 layers; if the number of rigid cylinders 105 is 3 layers, then the number of elastic cylinders 104 is 2 layers.

[0086] To ensure that the boss has sufficient mechanical properties, the radial thickness of the aforementioned boss is 8 to 40 mm, such as 8 mm, 16 mm, 25 mm, 36 mm or 40 mm.

[0087] Example 3

[0088] This embodiment provides an upper rotor, see [link / reference] Figure 10 It includes a blade, a blade clamp, and an upper rotor control assembly provided in Embodiment 1. The blade 1 is fixedly connected to the blade clamp via a main rotor counterweight bolt, and the blade clamp is connected to the linkage assembly.

[0089] Compared with the prior art, the beneficial effects of the upper rotor provided in this embodiment are basically the same as those of the upper rotor control assembly provided in Embodiment 1, and will not be described in detail here.

[0090] Specifically, the main rotor counterweight bolt includes a main rotor bolt 3, a dynamic balance counterweight 4, and a screw 7. The screw 7 and the dynamic balance counterweight 4 are located at the bolt head end of the main rotor bolt 3. One end of the screw 7 is fixedly connected to the bolt head, and the dynamic balance counterweight 4 is sleeved on the screw 7 and detachably connected to the screw 7. This type of main rotor counterweight bolt is suitable for dynamic balance adjustment of small helicopters. It should be noted that small helicopters refer to helicopters weighing less than 500 kg. The dynamic balance counterweight 4 is located at the bolt head end of the main rotor bolt 3 via the screw 7. When disassembling the rotor blade 1, the dynamic balance counterweight 4 can always be disassembled and installed together with the main rotor bolt 3, thus ensuring that the dynamic balance counterweight 4 will not be lost during disassembly. When reinstalling the rotor blade 1, there is no need to reassemble the dynamic balance counterweight 4, which can greatly improve the maintenance efficiency of the helicopter.

[0091] Meanwhile, since the screw 7 is set separately for installing the dynamic balance counterweight 4, the number and quality of the dynamic balance counterweight 4 can be effectively increased, thereby improving the helicopter's dynamic balance adjustment capability.

[0092] Furthermore, the structure of the aforementioned main rotor counterweight bolt can be improved based on the existing main rotor bolt 3, namely, by fixing the screw 7 to the bolt head end of the main rotor bolt 3, which is convenient and simple to operate and adaptable to industrial production and application.

[0093] To reduce the impact of the installation of the screw 7 on the structure of the main rotor bolt 3, the length ratio of the main rotor bolt 3 to the screw 7 can be controlled within the range of 3.0 to 5.0 (e.g., 3.0, 3.3, 3.6, 4.2, 4.5 or 5.0). For example, when the main rotor bolt 3 is 90 mm, the length of the screw 7 can be 20 mm.

[0094] In this embodiment, the counterweight bolt of the main propeller has a counterweight range of 0 to 90g. For example, the counterweight of the dynamic balance counterweight 4 is 25g, 40g, 60g, 75g or 90g.

[0095] During helicopter flight or maintenance, to prevent the dynamic balance weight 4 from falling off, the main rotor counterweight bolt also includes a clamping nut 5. The clamping nut 5 is sleeved on the screw 7 and is detachably threaded to the screw 7. The clamping nut 5 is located at the end of the dynamic balance weight 4 away from the main rotor bolt 3. The clamping nut 5 can limit the axial movement of the dynamic balance weight 4, preventing it from coming off the screw 7.

[0096] In practical applications, after repeated use and vibration, the clamping nut 5 may loosen or fall off. Therefore, the aforementioned main rotor counterweight bolt also includes a cotter pin 6 located at the end of the screw 7 away from the main rotor bolt 3. The cotter pin 6 is detachably fixed to the screw 7. The cotter pin 6 is located on the side of the clamping nut 5 away from the main rotor bolt 3. It can be understood that the end of the screw 7 away from the main rotor bolt 3 has a through hole, and the cotter pin 6 is inserted into the through hole. In this way, through the double cooperation of the clamping nut 5 and the cotter pin 6, the dynamic balance counterweight 4 can be basically prevented from falling off, thereby ensuring the flight safety of the helicopter.

[0097] Example 4

[0098] This embodiment provides an upper rotor, see [link / reference] Figures 11 to 13 It includes a spanwise counterweight assembly and an upper rotor control assembly provided in Embodiment 1.

[0099] Compared with the prior art, the beneficial effects of the upper rotor provided in this embodiment are basically the same as those of the upper rotor control assembly provided in Embodiment 1, and will not be described in detail here.

[0100] The spanwise counterweight assembly includes a first limiting block 12, a blade bolt 13, an elastic element 15, a spanwise counterweight 16, and an anti-loosening component. The upper end of the blade bolt 13 is provided with a blind hole. The elastic element 15 and the spanwise counterweight 16 are both located in the blind hole. The first limiting block 12 is connected to the upper end of the blind hole. The anti-loosening component connects the spanwise counterweight 16 and the first limiting block 12. This spanwise counterweight assembly utilizes blade bolts for spanwise configuration, placing the counterweight within the bolts. This avoids the disruption of the blade clamp material caused by drilling holes in the clamp, thus improving the clamp's fatigue resistance. It also avoids the increased material consumption associated with adding support rods to the blade bolt heads, reducing material size. An elastic element between the counterweight and the limiting block ensures that even with a small number of spanwise counterweights, they remain pressed against the bottom of the blind hole, preventing the counterweight from shifting within the blade bolt during flight and causing dynamic balance changes. An intermediate support and safety mechanism prevent loosening of the first limiting block while facilitating the removal and placement of the counterweight.

[0101] To ensure the effectiveness of the counterweight, the blind hole and the blade bolt 13 are set concentrically.

[0102] It should be noted that when blind holes are set in the blade bolt 13, it is necessary to ensure that the blade bolt 13 still has sufficient strength to withstand the centrifugal force of the blade after the internal material is removed, and that the blade bolt 13 is not damaged.

[0103] To avoid radial movement of the spanwise counterweight 16 along the blind hole, the cross-sectional area of ​​the blind hole is equal to the cross-sectional area of ​​the spanwise counterweight 16. This design prevents the spanwise counterweight 16 from shifting left and right inside the blade bolt 13 during flight, thus avoiding changes in dynamic balance. In this embodiment, the blind hole is a cylindrical hole with a diameter equal to the diameter of the spanwise counterweight 16. It should be noted that the direction perpendicular to the axis of the blade bolt 13 is defined as the transverse direction.

[0104] In this embodiment, the spanwise counterweight 16 is located at the lower end of the blind hole, the first limiting block 12 is located at the upper end of the blind hole, and the elastic element 15 is located between the first limiting block 12 and the spanwise counterweight 16 and is in a compressed state. Preferably, the elastic element 15 is a spring.

[0105] In this embodiment, the two ends of the elastic element 15 abut against the lower end of the first limiting block 12 and the upper end of the spanwise counterweight block 16, respectively, so that when there are fewer spanwise counterweight blocks 16, they are pressed tightly at the bottom of the blind hole, thus preventing the spanwise counterweight blocks 16 from moving up and down inside the blade bolt 13 during flight and causing changes in dynamic balance.

[0106] For connection with the first limiting block 12, the upper end of the blind hole is threaded, and the first limiting block 12 is threaded externally, with the first limiting block 12 threadedly connected to the upper end of the blind hole. In this embodiment, the first limiting block 12 is a tightening screw.

[0107] In order to connect with the anti-loosening component, the first limiting block 12 is provided with a first through hole and a second through hole. The first through hole and the second through hole are perpendicular to each other. The first through hole is concentric with the blind hole. The second through hole is connected to the first through hole and is located at the upper end of the first limiting block 12.

[0108] The anti-loosening component includes a central support column 14. The upper end of the central support column 14 is a columnar structure with a third through hole at the upper end and a second limiting block at the lower end. A limiting groove is provided at the bottom of the blind hole. The second limiting block cooperates with the limiting groove to restrict the rotation of the central support column 14. In this embodiment, the second limiting block has a square head. The longitudinal counterweight 16 has a fourth through hole. The cross-sectional area of ​​the fourth through hole is smaller than the cross-sectional area of ​​the second limiting block and equal to the cross-sectional area of ​​the upper end of the central support column 14. This ensures that the longitudinal counterweight 16 fitted on the central support column 14 has no lateral (radial) movement allowance and facilitates the removal of the longitudinal counterweight 16.

[0109] The anti-loosening component also includes a safety pin 11, which passes through the second through hole and the third through hole to further prevent the first limiting block 12 from loosening. In this embodiment, in order to facilitate alignment with the second through hole, multiple third through holes are provided. The third through holes are evenly distributed along the top axial direction of the intermediate support column 14. For example, there are 6 third through holes.

[0110] In this embodiment, after the middle support column 14 is installed, the first limiting block 12 (tightening screw) on the upper side is screwed in. It is important to ensure that the upper part of the middle support column 14 passes through the middle hole (first through hole) of the tightening screw. The second through hole of the first limiting block 12 is aligned with the upper hole (third through hole) of the middle support column 14, and the safety pin 11 is inserted. The tightening screw is secured by the square head side and the safety pin 11 to prevent loosening.

[0111] When installing the spanwise counterweight 16, remove the safety pin 11 at the top of the blade bolt 13, then remove the first limiting block 12 to expose sufficient space. Remove the elastic element 15, insert an appropriate number of spanwise counterweights 16, tighten the first limiting block 12, and connect the safety pin 11. When adjusting the number of spanwise counterweights 16, remove the safety pin 11 and the first limiting block 12 in sequence, lift the intermediate support 14 upwards, and due to the function of the second limiting block, the internal elastic element 15 and the spanwise counterweights 16 can be removed simultaneously. Adjust the number of spanwise counterweights 16 as needed, then align the second limiting block with the limiting groove, and connect the first limiting block 12 and the safety pin 11 in sequence. It should be noted that if the spanwise counterweights 16 installed in the blade bolt 13 still cannot achieve balance using the solution of this embodiment, the blade or hub itself needs to be checked.

[0112] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any changes or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in the present invention should be included within the scope of protection of the present invention.

Claims

1. A rotor control assembly, characterized in that, The upper rotor control assembly is located below the upper and lower rotors of the helicopter, and the upper rotor is controlled from below the upper rotor. The upper rotor control assembly includes a fixed plate, a moving plate, a collective pitch fixed ring, a collective pitch moving ring, a linkage assembly, and a connecting shaft; the collective pitch fixed ring and the collective pitch moving ring are rotatably connected by a spherical bearing, and the collective pitch moving ring is connected to the moving plate by a universal joint. The connecting shaft is a hollow structure. One end of the connecting rod assembly is rotatably connected to the moving disk, and the other end of the connecting rod assembly passes through the connecting shaft and is rotatably connected to the rotor clip of the upper rotor. The fixed disk and the moving disk are rotatably connected. The fixed disk includes an x-axis rod and a y-axis rod that is perpendicularly and fixedly connected to the x-axis rod. By driving the fixed disk to move simultaneously along the x-axis and y-axis, the fixed disk can be positioned at any position in the xy plane, thereby driving the moving disk to tilt at any angle within a threshold range. The movement of the fixed disk along the x-axis and y-axis of the upper rotor drives the moving disk to tilt, thereby realizing the periodic pitch change of the upper rotor. The upper rotor control assembly also includes a z-axis servo, a connector, and a support. The servo connection end of the connector is rotatably connected to the z-axis servo, the fixed ring connection end of the connector is rotatably connected to the collective pitch fixed ring, and the support is rotatably connected to any position between the two ends of the connector, so that the connector and the support form a seesaw-like structure. The connector is a fork-shaped component. The servo connection end of the connector is a closed end. The servo connection end is connected to the output shaft of the servo motor through a rod end bearing. The fixed ring connection end of the connector is an open end. A U-shaped component is fixed on the fixed ring. The fixed ring connection end is inserted into the U-shaped component and rotatably connected with the U-shaped component. It also includes a horn-shaped component, the upper end face of which is fixedly connected to the collective pitch ring, and the lower end face of which is rotatably connected to the swashplate; the horn-shaped component includes an upper end ring, a tilting rod, and a lower end plate, one end of which is fixedly connected to the upper end ring, and the other end of which is fixedly connected to the lower end plate; the upper end ring is fixedly connected to the collective pitch ring, and the lower end plate is rotatably connected to the swashplate via a universal joint; a through hole is provided on the lower end plate, and the connecting rod assembly passes through the through hole; During collective pitch motion, the collective pitch fixed ring moves along the z-axis of the upper rotor, driving the collective pitch moving ring to move along the z-axis of the upper rotor. The connecting rod assembly, moving plate, and fixed plate move upward as a whole.

2. The upper rotor control assembly according to claim 1, characterized in that, It also includes an x-axis servo and a y-axis servo, wherein the x-axis servo is connected to the x-axis rod and the y-axis servo is connected to the y-axis rod.

3. The upper rotor control assembly according to claim 2, characterized in that, The x-axis servo is connected to the x-axis rod via a rod end bearing, and the y-axis servo is connected to the y-axis rod via a rod end bearing.

4. The upper rotor control assembly according to claim 1, characterized in that, The linkage assembly includes a rod body and an L-shaped component; The L-shaped component includes a horizontal rod and a vertical rod connected to the horizontal rod. The end of the horizontal rod away from the vertical rod is connected to the rod body, and the end of the vertical rod away from the horizontal rod is rotatably connected to the tilting plate through a rod end bearing.

5. An upper rotor, characterized in that, Includes the upper rotor control assembly as described in any one of claims 1 to 4.

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