A six-arm rotor system for a heavy helicopter used in rotor model wind tunnel tests

Abstract

A six-arm rotor system for a heavy helicopter in rotor model wind tunnel tests, belonging to the field of heavy helicopter rotor systems. It includes a hub central component assembly, a blade grip assembly, a swashplate assembly, a damper, a pitch change rocker arm, a pitch change pull rod, and a rotating part. An upward flapping limiter is provided at the top of the hub central component, and a downward flapping limiter is installed on the rotor shaft and is arranged at the bottom of the hub central component. The blade grip assembly is installed on the hub central component. A swashplate assembly is sleeved on the rotor shaft below the downward flapping limiter. Both ends of the damper are connected to the blade grip assembly and the hub central component respectively. The pitch change rocker arm is installed on the blade grip assembly. Both ends of the pitch change pull rod are connected to the pitch change rocker arm and the swashplate assembly respectively. Both ends of the rotating part are connected to the upward flapping limiter and the swashplate assembly respectively. The present invention meets the requirements of the large takeoff weight of heavy helicopters and can conduct rotor model tests in a wind tunnel, improving the safety and reliability of the rotor system.

Description

Technical Field

[0001] The present invention relates to a six-arm rotor system for a heavy helicopter in a rotor model wind tunnel test, and belongs to the field of heavy helicopter rotor systems. Background Art

[0002] Heavy helicopters can not only transport large military equipment, conduct rapid troop deployment, supply combat materials such as weapons and ammunition, and conduct combat search and rescue, but also evacuate trapped personnel or the wounded in major rescue and disaster relief operations, playing a major role in both military and civilian fields. As the core component of a helicopter, the rotor system can directly affect the aerodynamic performance, reliability, flight quality, etc. of the helicopter, and is the technical core of helicopter research and development. Rotor model wind tunnel tests have always been an important means to study rotor performance, aerodynamic characteristics, and aerodynamic interference characteristics, and to provide quantitative aerodynamic data for helicopter model design. However, at present, most conventional helicopter rotor systems are of four-arm or five-arm structures, which cannot meet the requirements of the large takeoff weight of heavy helicopters. At the same time, due to the complex structure and large size, they cannot be used for rotor model tests in a wind tunnel.

[0003] Therefore, there is an urgent need to propose a six-arm rotor system for a heavy helicopter in a rotor model wind tunnel test to solve the above technical problems. Summary of the Invention

[0004] The object of the present invention is to provide a six-arm rotor system for a heavy helicopter in a rotor model wind tunnel test, which can meet the requirements of the large takeoff weight of heavy helicopters and can be used for rotor model tests in a wind tunnel. A brief overview of the present invention is given below to provide a basic understanding of certain aspects of the present invention. It should be understood that this overview is not an exhaustive overview of the present invention. It is not intended to identify the key or important parts of the present invention, nor is it intended to limit the scope of the present invention.

[0005] Technical Solution of the Present Invention

[0006] A six-armed rotor system for a heavy-lift helicopter in a rotor model wind tunnel test, comprising a hub central component assembly, a blade grip assembly, a swashplate assembly, dampers, pitch change rockers, pitch change tie rods, and a rotating part. The hub central component assembly includes a hub central component, an up-flapping limiter, a down-flapping limiter, and a rotor shaft. The hub central component is mounted on the rotor shaft. An up-flapping limiter is provided at the top of the hub central component. The down-flapping limiter is mounted on the rotor shaft and is provided at the bottom of the hub central component. The hub central component, the up-flapping limiter, the down-flapping limiter, and the rotor shaft are coaxially arranged. The blade grip assembly is mounted on the hub central component. A swashplate assembly is sleeved on the rotor shaft below the down-flapping limiter. Both ends of the damper are respectively connected to the blade grip assembly and the hub central component. The pitch change rocker is mounted on the blade grip assembly. Both ends of the pitch change tie rod are respectively connected to the pitch change rocker and the swashplate assembly. Both ends of the rotating part are respectively connected to the down-flapping limiter and the swashplate assembly.

[0007] Preferably: The blade grip assembly includes a blade clamp, an elastic bearing, and a limit stop. One side of the blade clamp is a blade arm, and the other side is a U-shaped arm. Limit stops are provided at both the top and bottom of the U-shaped arm. An elastic bearing is clamped in the middle of the U-shaped arm. The elastic bearing and the limit stop are fixed to the U-shaped arm through a blade grip fixing bolt. The hub central component has a plurality of connecting clamp arms, and the connecting clamp arms are sleeved inside the U-shaped arm and are clamped and connected to the elastic bearing through an elastic bearing connecting bolt.

[0008] Preferably: The swashplate assembly includes a rotating ring, a rotating ring gland, a non-rotating ring gland, a retaining ring, a guide tube, a spherical hinge, a thin-wall bearing, and a non-rotating ring. The guide tube is sleeved on the rotor shaft, and a spherical hinge is slidably sleeved outside the guide tube. The non-rotating ring gland is fixedly installed on the top of the non-rotating ring. The inner sides of the non-rotating ring gland and the non-rotating ring are both matched with the outer spherical surface of the spherical hinge. The rotating ring gland is installed on the top of the rotating ring. The inner side of the rotating ring is installed on the outside of the non-rotating ring through a thin-wall bearing. Retaining rings are also provided on the outside of the top and bottom of the guide tube.

[0009] Preferably: The pitch change rocker is connected to the inner wall surface of the blade clamp by bolts.

[0010] Preferably: The lower end of the rotating part is connected to the rotating ring by bolts.

[0011] Preferably: It further includes an anti-torsion arm, and both ends of the anti-torsion arm are respectively fixedly connected to the arm of the non-rotating ring and the bottom end of the guide tube.

[0012] The present invention has the following beneficial effects:

[0013] 1. The present invention adopts a six-armed hub structure, which can meet the requirements of a heavy-lift helicopter with a large takeoff weight and high transportation efficiency.

[0014] 2. The present invention uses elastic bearings to replace the flapping hinge, lead-lag hinge and pitch hinge of the traditional articulated rotor, reducing the structural size and the number of parts, and is applicable to the wind tunnel test of the rotor model of a heavy helicopter.

[0015] 3. The present invention designs an up-flapping limiter and a down-flapping limiter on the hub, providing limit protection for the flapping motion of the blade, and improving the safety and reliability of the rotor system. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 is a three-dimensional view of a six-arm rotor system of a heavy helicopter for wind tunnel test of a rotor model;

[0017] Figure 2 is an assembled installation view of the hub central component assembly;

[0018] Figure 3 is a schematic structural view of the blade grip assembly;

[0019] Figure 4 is an exploded view of the blade grip assembly;

[0020] Figure 5 is a three-dimensional view of the blade grip assembly;

[0021] Figure 6 is an assembled installation view of the swashplate assembly;

[0022] Figure 7 is an assembled installation view of the blade grip assembly and the connecting clamp arm;

[0023] Figure 8 is an assembled installation view of the rotating part and the rotating ring.

[0024] In the figures: 1-1 - hub central component assembly, 1-2 - blade grip assembly, 1-3 - swashplate assembly, 1 - hub central component, 2 - up-flapping limiter, 3 - down-flapping limiter, 4 - rotor shaft, 5 - blade fixture, 6 - elastic bearing, 7 - limit stop, 8 - damper, 9 - pitch rocker arm, 10 - pitch pull rod, 11 - rotating part, 12 - anti-twist arm, 13 - rotating ring, 14 - rotating ring gland, 15 - non-rotating ring gland, 16 - retaining ring, 17 - guide tube, 18 - ball hinge, 19 - thin-wall bearing, 20 - non-rotating ring, 101 - connecting clamp arm, 501 - U-shaped support arm, 502 - blade grip fixing bolt, 601 - elastic bearing connecting bolt. DETAILED DESCRIPTION OF THE INVENTION

[0025] To make the objectives, technical solutions, and advantages of the present invention more clear and understandable, the present invention will be described below through specific embodiments shown in the accompanying drawings. However, it should be understood that these descriptions are merely exemplary and are not intended to limit the scope of the present invention. In addition, in the following description, descriptions of well-known structures and technologies are omitted to avoid unnecessarily confusing the concepts of the present invention.

[0026] The connections mentioned in the present invention are divided into fixed connections and detachable connections. The fixed connections, that is, non-detachable connections, include but are not limited to conventional fixed connection methods such as hemming connection, rivet connection, bonding connection, and welding connection. The detachable connections include but are not limited to conventional disassembly methods such as screw connection, snap connection, pin connection, and hinge connection. When the specific connection method is not clearly defined, it is defaulted that at least one connection method can always be found among the existing connection methods to achieve this function, and those skilled in the art can select it according to their needs. For example: welding connection is selected for fixed connection, and hinge connection is selected for detachable connection.

[0027] Example: In combination with Figures 1 - 8 To illustrate this embodiment, a six-arm rotor system of a heavy helicopter for rotor model wind tunnel test in this embodiment includes a hub central component assembly 1-1, a blade grip assembly 1-2, a swashplate assembly 1-3, a damper 8, a pitch change rocker 9, a pitch change pull rod 10, and a belt rotating component 11;

[0028] The hub central component assembly 1-1 includes a hub central component 1, an up-flapping limiter 2, a down-flapping limiter 3, and a rotor shaft 4. The hub central component 1 is installed on the rotor shaft 4 and is positioned through a spline groove with the rotor shaft 4 to transmit the torque of the rotor shaft 4 and the centrifugal force from the blade, and to provide an installation interface for the up-flapping limiter 2 and the down-flapping limiter 3. An up-flapping limiter 2 is provided at the top of the hub central component 1. The up-flapping limiter 2 and the hub central component 1 are connected to the rotor shaft 4 through precision reamed bolts to prevent excessive upward flapping when the blade suddenly stops rotating. The down-flapping limiter 3 is installed on the rotor shaft 4 through bolts and is provided at the bottom of the hub central component 1 to prevent excessive downward flapping of the blade under the action of its own weight when the blade suddenly stops rotating. The hub central component 1, the up-flapping limiter 2, the down-flapping limiter 3, and the rotor shaft 4 are coaxially arranged;

[0029] The blade grip assembly 1-2 is installed on the hub central component 1, and a swashplate assembly 1-3 is sleeved on the rotor shaft 4 below the down-flapping limiter 3;

[0030] Both ends of the damper 8 are respectively connected to the blade grip assembly 1-2 and the hub central component 1. Further, one end of the damper 8 is connected to the hub central component 1 through a rod end spherical bearing and a bolt, and the other end is connected to the blade fixture 5 through a rod end spherical bearing and a bolt to avoid ground resonance and air resonance.

[0031] The pitch-changing rocker arm 9 is installed on the blade grip assembly 1-2. Further, the pitch-changing rocker arm 9 is connected to the inner wall surface of the blade clamp 5 through bolts to transmit the rotor control force.

[0032] Both ends of the pitch-changing pull rod 10 are respectively connected to the pitch-changing rocker arm 9 and the swashplate assembly 1-3. Further, one end of the pitch-changing pull rod 10 is connected to the rotating ring 13 through a rod-end spherical bearing, and the other end is connected to the pitch-changing rocker arm 9 through a rod-end spherical bearing, so as to realize the pitch-changing movement of the blade.

[0033] Both ends of the belt rotating member 11 are respectively connected to the downward swing limiter 3 and the swashplate assembly 1-3. Further, the upper end of the belt rotating member 11 is fixedly connected to the side surface of the downward swing limiter 3 through bolts, and the lower end of the belt rotating member 11 is connected to the rotating ring 13 through bolts, so as to realize the synchronous rotation of the rotating ring 13 and the rotor shaft 4.

[0034] The blade grip assembly 1-2 includes a blade clamp 5, an elastic bearing 6 and a limit stop 7. One side of the blade clamp 5 is a blade arm, and the other side of the blade clamp 5 is a U-shaped arm 501. Limit stops 7 are arranged at the top and bottom of the U-shaped arm 501, and an elastic bearing 6 is clamped in the middle of the U-shaped arm 501. One end of the elastic bearing 6 and the limit stop 7 are fixedly penetrated on the U-shaped arm 501 through blade grip fixing bolts 502. The hub central member 1 has a plurality of connecting clamp arms 101. As Figure 1 shown, the number of connecting clamp arms 101 in this embodiment is 6, which are arranged in a circumferential uniform array. The connecting clamp arms 101 are sleeved in the U-shaped arm 501 and are clamped and connected to the other end of the elastic bearing 6 through an elastic bearing connecting bolt 601 by means of a groove. The elastic bearing 6 is formed by vulcanizing and bonding rubber and a metal spacer, and realizes the pitch-changing movement of the blade and transmits the blade load through the shear elastic deformation of the rubber.

[0035] The swashplate assembly 1-3 includes a rotating ring 13, a rotating ring gland 14, a non-rotating ring gland 15, a retaining ring 16, a guide tube 17, a ball joint 18, a thin-wall bearing 19, and a non-rotating ring 20. The guide tube 17 is sleeved on the rotor shaft 4. Further, the guide tube 17 is inserted from the bottom end of the rotor shaft 4 and cooperates with the rotor shaft 4. A ball joint 18 is slidably sleeved on the outer side of the guide tube 17. The ball joint 18 is inserted from the top end of the guide tube 17 and is in keyway fit with the outer surface of the guide tube 17. The non-rotating ring gland 15 is fixedly installed on the top of the non-rotating ring 20 through a precision reamed hole bolt. The inner sides of the non-rotating ring gland 15 and the non-rotating ring 20 are both in spherical surface fit with the outer spherical surface of the ball joint 18. The rotating ring gland 14 is installed on the top of the rotating ring 13. The inner side of the rotating ring 13 is installed on the outer side of the non-rotating ring 20 through a thin-wall bearing 19. The outer ring of the thin-wall bearing 19 is in fit with the inner surface of the rotating ring 13, so as to achieve relative rotation. Retaining rings 16 are also arranged on the outer sides of the top and bottom of the guide tube 17. The retaining rings 16 are inserted from the top end of the guide tube 17 and are respectively arranged at the top and bottom ends of the guide tube 17 to prevent the swashplate assembly 1-3 from moving beyond the limit and play a protective role.

[0036] The ball joint 18 can slide up and down along the outer surface of the guide tube 17 to realize the collective pitch control of the rotor. The rotating ring 13 and the non-rotating ring 20 can deflect together around the center of the ball joint 18 to realize the cyclic pitch control of the rotor. The rotating ring 13 can rotate relative to the non-rotating ring 20 and keep the mutual plane angles consistent.

[0037] It further includes an anti-torsion arm 12. Both ends of the anti-torsion arm 12 are fixedly connected to the arm of the non-rotating ring 20 and the bottom end of the guide tube 17 respectively. Further, the upper end of the anti-torsion arm 12 is connected to the arm of the non-rotating ring 20 through a bolt, and the lower end of the anti-torsion arm 12 is fixedly connected to the bottom end of the guide tube 17 through a bolt. When the non-rotating ring 20 moves around the ball joint 18, the anti-torsion arm 12 transfers the torque to the guide tube 17, thereby restricting the non-rotating ring 20 from rotating around the rotor axis and not affecting the cyclic pitch change.

[0038] This embodiment adopts a hub structure with six arms, which can meet the requirements of heavy helicopters with large takeoff weights and high transportation efficiency; elastic bearings are used to replace the flapping hinge, lead-lag hinge, and pitch change hinge of the traditional articulated rotor, reducing the structural size and the number of parts, and is applicable to the wind tunnel test of the heavy helicopter rotor model. By designing an up-flapping limiter and a down-flapping limiter on the hub, limit protection is provided for the flapping movement of the blade, improving the safety and reliability of the entire rotor system.

[0039] It should be noted that in the above embodiments, as long as the technical solutions are not contradictory, they can be arranged and combined. Those skilled in the art can exhaust all possibilities based on the mathematical knowledge of permutations and combinations. Therefore, the present invention will no longer describe the technical solutions after permutation and combination one by one, but it should be understood that the technical solutions after permutation and combination have been disclosed by the present invention.

[0040] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and changes. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A six-arm rotor system for a heavy helicopter used in rotor model wind tunnel tests, characterized in that: It includes a hub central component assembly (1-1), a blade grip assembly (1-2), a swashplate assembly (1-3), a damper (8), a pitch change rocker arm (9), a pitch change pull rod (10) and a rotating member (11). The hub central component assembly (1-1) includes a hub central component (1), an upswing limiter (2), a downswing limiter (3) and a rotor shaft (4). The hub central component (1) is mounted on the rotor shaft (4). The upswing limiter (2) is arranged at the top of the hub central component (1). The downswing limiter (3) is mounted on the rotor shaft (4) and is arranged at the bottom of the hub central component (1). The hub central component (1), the upswing limiter (2), the downswing limiter (3) and the rotor shaft (4) are coaxially arranged. The blade grip assembly (1-2) is mounted on the hub central component (1). The swashplate assembly (1-3) is sleeved on the rotor shaft (4) below the downswing limiter (3). Both ends of the damper (8) are respectively connected with the blade grip assembly (1-2) and the hub central component (1). The pitch change rocker arm (9) is mounted on the blade grip assembly (1-2). Both ends of the pitch change pull rod (10) are respectively connected with the pitch change rocker arm (9) and the swashplate assembly (1-3). Both ends of the rotating member (11) are respectively connected with the downswing limiter (3) and the swashplate assembly (1-3); The blade grip assembly (1-2) includes a blade clamp (5), an elastic bearing (6) and a limit stop (7). One side of the blade clamp (5) is a blade arm, and the other side of the blade clamp (5) is a U-shaped arm (501). Limit stops (7) are arranged at both the top and the bottom of the U-shaped arm (501). An elastic bearing (6) is clamped in the middle of the U-shaped arm (501). The elastic bearing (6) and the limit stop (7) are fixed on the U-shaped arm (501) through a blade clamp fixing bolt (502). The hub central component (1) has a plurality of connecting clamp arms (101). The connecting clamp arms (101) are sleeved in the U-shaped arm (501) and are clamped and connected with the elastic bearing (6) through an elastic bearing connecting bolt (601). The number of the connecting clamp arms (101) is 6, and they are arranged in a circumferentially uniform array. The connecting clamp arms (101) are sleeved in the U-shaped arm (501) and are clamped and connected with the other end of the elastic bearing (6) through the elastic bearing connecting bolt (601) by using a groove. The elastic bearing (6) is formed by vulcanizing and bonding rubber and a metal spacer, and realizes the pitch change movement of the blade and transmits the blade load through the shear elastic deformation of the rubber; The swashplate assembly (1-3) includes a rotating ring (13), a rotating ring gland (14), a non-rotating ring gland (15), a retaining ring (16), a guide tube (17), a ball joint (18), a thin-wall bearing (19), and a non-rotating ring (20). The guide tube (17) is sleeved on the rotor shaft (4). A ball joint (18) is slidably sleeved on the outer side of the guide tube (17). The non-rotating ring gland (15) is fixedly installed on the top of the non-rotating ring (20). The inner sides of the non-rotating ring gland (15) and the non-rotating ring (20) are both in fit with the outer spherical surface of the ball joint (18). The rotating ring gland (14) is installed on the top of the rotating ring (13). The inner side of the rotating ring (13) is installed on the outer side of the non-rotating ring (20) through a thin-wall bearing (19). Retaining rings (16) are also provided on the outer sides of the top and bottom of the guide tube (17). The ball joint (18) slides up and down along the outer surface of the guide tube (17) to achieve the collective pitch control of the rotor. The rotating ring (13) and the non-rotating ring (20) deflect together around the center of the ball joint (18) to achieve the cyclic pitch control of the rotor. The rotating ring (13) rotates relative to the non-rotating ring (20) and maintains the same plane angle with each other.

2. The six-arm rotor system of a heavy helicopter for rotor model wind tunnel test according to claim 1, characterized in that: The pitch change rocker arm (9) is connected to the inner wall surface of the blade clamp (5) by bolts.

3. A six-arm rotor system for a heavy helicopter used in rotor model wind tunnel tests according to claim 2, characterized in that: The lower end of the belt rotating part (11) is connected to the rotating ring (13) by bolts.

4. The six-arm rotor system of a heavy helicopter for rotor model wind tunnel test according to claim 3, characterized in that: It further includes an anti-torsion arm (12). Both ends of the anti-torsion arm (12) are fixedly connected to the support arm of the non-rotating ring (20) and the bottom end of the guide tube (17) respectively.

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