Variable-pitch pull rod adjusting and fixing device and method

Abstract

The invention belongs to the technical field of aircraft design, and particularly relates to a variable-pitch pull rod adjusting and fixing device and method. The device comprises a base and four column bodies integrally formed with the base. U-shaped grooves are formed in the upper part and the lower part of the base; the side wall of the U-shaped groove is parallel to the side wall of the rectangular hole, and an angle alpha is formed between the side wall of the U-shaped groove and the vertical direction and ranges from 3 degrees to 8 degrees; the four columns are respectively positioned at four corners of the base; and the A surface of each column body is coplanar with the side wall of the U-shaped groove.

Description

Technical Field

[0001] This invention belongs to the field of aircraft design technology, and specifically relates to a variable pitch tie rod adjustment and fixing device and method. Background Technology

[0002] Most helicopters currently rely on the control stick position provided by the main rotor servo in the flight control system for changes in flight attitude. Because each servo introduces some error during maintenance and replacement, a flight control servo reference adjustment is necessary when installing a new servo. However, during this adjustment, the stick tip should not wobble significantly; ideally, it should be completely still. If the stick tip wobbles continuously during the adjustment, it will affect the lifespan and performance of the bearings inside the stick tip, leading to inaccurate servo reference angle control. This can cause the helicopter to exhibit inappropriate flight attitude, potentially affecting flight stability or even causing loss of control. Therefore, maintaining a fixed pitch control stick tip during flight control servo reference adjustment is crucial.

[0003] With the ever-changing international situation, helicopter training will continue to increase, and the probability of various types of helicopters encountering severe damage will gradually increase. Among them, the probability of main rotor servo motors that control the automatic swashplate in the flight control system being damaged, needing replacement or upgrades will also increase significantly. In order to meet the intensity requirements of training and to quickly carry out helicopter repair or upgrade work, there is an urgent need for a flight control servo reference adjustment technology that is simple to operate and safe and reliable to use. Summary of the Invention

[0004] Purpose of the invention: To propose a variable pitch lever adjustment and fixing device and method to prevent the lever head from shaking during flight control servo reference adjustment.

[0005] Technical solution: A variable pitch tie rod adjustment and fixing device includes a base and four columns integrally formed with the base; A rectangular hole is opened in the middle of the base, and U-shaped grooves are opened at the top and bottom; the side wall of the U-shaped groove is parallel to the side wall of the rectangular hole and forms an angle α with the vertical direction, with a value range of 3°~8°; The four pillars are located at the four corners of the base; The A-side of each column is coplanar with the sidewall of the U-shaped groove.

[0006] Furthermore, the first column in the upper left corner includes three sides: 2A, 2B, and 2C. Side 2B is parallel to the horizontal direction, and side 2C is an arc surface. The horizontal surface is convenient for machining, and the arc surface is convenient for assembly.

[0007] Furthermore, the first column in the upper left corner includes two bottom surfaces, 2E and 2F. The bottom surface 2E is parallel to the bottom surface of the base, and the bottom surface 2F is a spherical surface. The transition from the 2B and 2C surfaces to the 2A surface ensures the stability of the device and plays a supporting role.

[0008] Furthermore, the second pillar in the upper right corner includes four sides: 3A, 3B, 3C, and 3D. Surface 3B is parallel to the bottom of the U-shaped groove. This parallelism allows it to be integrated with the ground, ensuring the stability of the ground support. The angle between side 3C and side 3A is β, with a value range of 3°~4°. The 3D side is curved, which facilitates assembly.

[0009] Furthermore, the second column in the upper right corner includes two base surfaces, 3E and 3F; The bottom surface of 3E is parallel to the bottom surface of the base, and the bottom surface of 3F is a spherical surface. The transition from the 3B, 3C and 3D surfaces to the 3A surface ensures the stability of the device and plays a supporting role.

[0010] Furthermore, the third pillar in the lower right corner includes four sides: 4A, 4B, 4C, and 4D. Among them, surfaces 4B and 4D are planes parallel to the horizontal direction, and parallel planes facilitate machining; The 4C surface consists of three segments: an inclined plane, a horizontal plane, and a vertical plane. The angle between the inclined plane and the vertical direction is 4°. Furthermore, the third column in the lower right corner includes two bottom surfaces, 4E and 4F. The bottom surface 4E is parallel to the bottom surface of the base, and the bottom surface 4F is a spherical surface. It transitions from the 4B, 4C and 4D surfaces to the 4A surface. The transition to the A surface ensures the stability of the device and plays a supporting role.

[0011] Furthermore, the fourth column in the lower left corner includes four sides: 5A, 5B, 5C, and 5D; among them, sides 5B and 5D are planes parallel to the horizontal direction, and side 5C is a plane parallel to the vertical direction.

[0012] Furthermore, the fourth pillar in the lower left corner includes two base surfaces, 5E and 5F; The bottom surface of 5E is parallel to the bottom surface of the base, and the bottom surface of 5F is a spherical surface. The transition from surface 5B, surface 5C and surface 5D to surface 5A ensures assembly, and the transition to surface A ensures the stability of the device and plays a supporting role.

[0013] A method for adjusting and fixing a variable pitch tie rod, implemented based on the aforementioned variable pitch tie rod adjustment and fixing device, comprises the following steps: Step 1: Level the aircraft. After leveling the aircraft, power it on and the flight control computer sends a zero-position command to the main rotor servo. Step 2: Rotate the main propeller to the main propeller servo position by turning the propeller, adjust the angle of one of the main propellers electrically, and then start adjusting the pitch control levers of the remaining propellers; Step 3: When rotating other main propellers to the position of this main propeller servo via the propeller control operation, use the pitch control rod adjustment and fixing device to fix the pitch control rod head to ensure that the pitch control rod head does not rotate when adjusting the pitch control rod body, the self-locking nut of the rod, and the stop washer; Step 4: Adjust the pitch control rod, the self-locking nut, and the locking washer until the main propeller reaches the specified angle; Step 5: Secure the self-locking nut and locking washer of the pull rod with a fuse; Step Six: Check the securing of the device and remove any excess material; Step 7: Disassemble the variable pitch tie rod and adjust the fixing device.

[0014] In summary, the beneficial effects of the present invention are as follows: This invention relates to a quick-fixing device for adjusting the pitch control rod in helicopter flight control servo reference adjustment technology. It features simple installation, quick fitting and fixing, and convenient disassembly. It can meet the requirements for quick fixing of the pitch control rod in flight control servo reference adjustment technology, and complete the rapid adjustment of the flight control servo reference, providing strong support for flight control data. Attached Figure Description

[0015] Figure 1 Schematic diagram of the variable pitch tie rod adjustment and fixing device: 1. Base; 2. First column; 3. Second column; 4. Third column; 5. Fourth column; Figure 2 Schematic diagram showing the four cylindrical surfaces of the variable pitch tie rod adjustment and fixing device; Figure 3 Schematic diagram of the adjustment and fixing method of the pitch control rod: 11. Main propeller; 12. Pitch control rod adjustment and fixing device; 13. Pitch control rod head; 14. Pitch control rod self-locking nut; 15. Fuse; 16. Stop washer; 17. Pitch control rod body. Detailed Implementation

[0016] The variable pitch tie rod adjustment and fixing device consists of a base and four columns integrally formed with the base; a rectangular hole is opened in the middle of the base, and U-shaped grooves are opened at the top and bottom; the side wall of the U-shaped groove is parallel to the side wall of the rectangular hole and forms an angle α with the vertical direction, with a value range of 3°~8°; the four columns are located at the four corners of the base; the A surface of each column is coplanar with the side wall of the U-shaped groove, and the shape of the four columns is adapted to fit their assembly relationship so that they can effectively fit the servo reference tie rod bearing and ensure the assemblability with the main propeller mounting space.

[0017] The first column in the upper left corner includes three sides: 2A, 2B, and 2C. Side 2B is parallel to the horizontal direction, while side 2C is an arc surface. The horizontal side facilitates machining, and the arc surface facilitates assembly. The first column in the upper left corner also includes two bottom surfaces: 2E and 2F. Bottom surface 2E is parallel to the bottom surface of the base, while bottom surface 2F is a near-spherical surface. The transition from sides 2B and 2C to side 2A ensures the stability of the device and provides support.

[0018] The second column in the upper right corner includes four sides: 3A, 3B, 3C, and 3D. Side 3B is parallel to the bottom of the U-shaped groove, allowing it to be integrated with the ground and ensuring the stability of the support. The angle between side 3C and side 3A is β, ranging from 3° to 4°. Side 3D is an arc surface for easy assembly. The second column in the upper right corner also includes two bottom surfaces: 3E and 3F. Bottom surface 3E is parallel to the bottom surface of the base, while bottom surface 3F is a near-spherical surface. The transition from sides 3B, 3C, and 3D to side 3A ensures the stability of the device and provides support.

[0019] The third column in the lower right corner includes four sides: 4A, 4B, 4C, and 4D. Among them, sides 4B and 4D are planes parallel to the horizontal direction, which facilitates machining. Side 4C consists of three sections: an inclined plane, a horizontal plane, and a vertical plane. The angle between the inclined plane and the vertical direction is 4°. The third column in the lower right corner includes two bottom surfaces: 4E and 4F. Bottom surface 4E is parallel to the bottom surface of the base, and bottom surface 4F is a spherical surface. The transition from sides 4B, 4C, and 4D to side 4A ensures the stability of the device and provides support.

[0020] The fourth pillar in the lower left corner includes four sides: 5A, 5B, 5C, and 5D. Sides 5B and 5D are planes parallel to the horizontal direction, while 5C is a plane parallel to the vertical direction. The fourth pillar in the lower left corner also includes two bottom surfaces: 5E and 5F. Bottom surface 5E is parallel to the base bottom surface, while bottom surface 5F is a spherical surface. The transition from sides 5B, 5C, and 5D to surface 5A ensures proper assembly, and the transition to surface A ensures the stability of the device's fastening, thus providing support.

[0021] This device ensures that the bearings of the servo linkage do not twist during servo reference adjustment, effectively extending the service life of the servo linkage bearings. This allows the displacement of the servo linkage to be effectively transmitted to the main rotor, thereby ensuring the flight stability of the helicopter and enabling effective flight control. Although this device may appear to be just a pitch linkage adjustment and fixing device, its significance goes far beyond a simple "fixing device." It is a crucial bridge connecting the flight control system and actual flight safety, and a core guarantee for ensuring the precise, reliable, and consistent operation of the helicopter flight control system. Ultimately, it serves the three core aviation objectives of flight safety, maintenance efficiency, and economy.

[0022] The usage method is as follows: First, level the aircraft. After leveling, power on the aircraft, and the flight control computer sends a zero-position command to the main rotor servo. Rotate the main rotor to the servo position using the rotor control operation. After electrically adjusting the angle of one main rotor, begin adjusting the pitch control rods of the remaining rotors. Then, rotate the other main rotors to the servo position using the rotor control operation. Secure the pitch control rod head and its bearing using the pitch control rod adjustment and fixing device to ensure that the pitch control rod head and its bearing do not rotate when adjusting the pitch control rod body, the self-locking nut, and the locking washer. Adjust the pitch control rod body, the self-locking nut, and the locking washer until the main rotor reaches the specified angle. Secure the self-locking nut and locking washer with a fuse. Check the fixing and remove any excess material. Disassemble the pitch control rod adjustment and fixing device.

Claims

1. A variable pitch tie rod adjustment and fixing device, characterized in that: The device includes a base and four pillars integrally formed with the base; A rectangular hole is opened in the middle of the base, and U-shaped grooves are opened at the top and bottom; the side wall of the U-shaped groove is parallel to the side wall of the rectangular hole and forms an angle α with the vertical direction, with a value range of 3°~8°; The four pillars are located at the four corners of the base; The A-side of each column is coplanar with the sidewall of the U-shaped groove.

2. The apparatus according to claim 1, characterized in that: The first column in the upper left corner has three sides: 2A, 2B, and 2C. Side 2B is parallel to the horizontal direction, and side 2C is a curved surface.

3. The apparatus according to claim 2, characterized in that: The first column in the upper left corner has two bottom surfaces, 2E and 2F. The bottom surface 2E is parallel to the bottom surface of the base, and the bottom surface 2F is a spherical surface that transitions from the 2B and 2C surfaces to the 2A surface.

4. The apparatus according to claim 1, characterized in that: The second pillar in the upper right corner includes four sides: 3A, 3B, 3C, and 3D. Surface 3B is parallel to the bottom of the U-shaped groove; The angle between side 3C and side 3A is β, with a value range of 3°~4°. The 3D side is a curved surface.

5. The apparatus according to claim 4, characterized in that: The second column in the upper right corner includes two base surfaces, 3E and 3F; The bottom surface of 3E is parallel to the bottom surface of the base, the bottom surface of 3F is a spherical surface, and the transition from the 3B, 3C and 3D surfaces to the 3A surface is through.

6. The apparatus according to claim 1, characterized in that: The third pillar in the lower right corner includes four sides: 4A, 4B, 4C, and 4D. Among them, surfaces 4B and 4D are planes parallel to the horizontal direction; The 4C surface consists of three segments: an inclined plane, a horizontal plane, and a vertical plane. The angle between the inclined plane and the vertical direction is 4°.

7. The apparatus according to claim 6, characterized in that: The third column in the lower right corner includes two bottom surfaces, 4E and 4F. The bottom surface 4E is parallel to the bottom surface of the base, and the bottom surface 4F is a spherical surface that transitions from surface 4B, surface 4C, and surface 4D to surface 3A.

8. The apparatus according to claim 1, characterized in that: The fourth pillar in the lower left corner includes four sides: 5A, 5B, 5C, and 5D. Among them, sides 5B and 5D are planes parallel to the horizontal direction, and side 5C is a plane parallel to the vertical direction.

9. The apparatus according to claim 8, characterized in that: The fourth pillar in the lower left corner includes two base surfaces, 5E and 5F; The bottom surface of 5E is parallel to the bottom surface of the base, the bottom surface of 5F is a spherical surface, and the transition from the bottom surface of 5B, 5C and 5D to the bottom surface of 5A is gradual.

10. A method for adjusting and fixing a variable pitch tie rod, implemented based on the variable pitch tie rod adjusting and fixing device according to any one of claims 1-9, characterized in that: The steps are as follows: Step 1: Level the aircraft. After leveling the aircraft, power it on and the flight control computer sends a zero-position command to the main rotor servo. Step 2: Rotate the main propeller to the main propeller servo position by turning the propeller, adjust the angle of one of the main propellers electrically, and then start adjusting the pitch control levers of the remaining propellers; Step 3: When rotating other main propellers to the position of this main propeller servo via the propeller control operation, use the pitch control rod adjustment and fixing device to fix the pitch control rod head to ensure that the pitch control rod head does not rotate when adjusting the pitch control rod body, the self-locking nut of the rod, and the stop washer; Step 4: Adjust the pitch control rod, the self-locking nut, and the locking washer until the main propeller reaches the specified angle; Step 5: Secure the self-locking nut and locking washer of the pull rod with a fuse; Step Six: Check the securing of the device and remove any excess material; Step 7: Disassemble the variable pitch tie rod and adjust the fixing device.

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