Friction piece device for restraining adverse vibration of rudder
By adding a friction component to the rudder shaft, the frictional torque is used to balance the inertial torque, solving the problems of high cost and maintenance, and achieving a low-cost and effective vibration suppression effect, which is suitable for rudder systems.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- BEIJING BEIHANG TIANYU ZHANGYING UAV TECH CO LTD
- Filing Date
- 2025-12-28
- Publication Date
- 2026-05-08
AI Technical Summary
Existing technologies for controlling rudder system clearance suffer from high design and maintenance costs, and increased clearance can lead to undesirable oscillations that are difficult to suppress effectively.
A friction device is used to balance the inertial torque by increasing the friction torque at the rudder shaft. It includes an upper rotating component, a lower fixed base, and a semi-enclosed fixed component. The friction torque between the friction plate and the metal friction head is used to suppress vibration, and the position of the slider is adjusted to adjust the magnitude of the friction torque.
It reduces the design and manufacturing costs of the structure and equipment, reduces maintenance requirements, has a long service life, hardly affects aircraft performance, and can effectively suppress adverse oscillations and vibrations.
Smart Images
Figure CN121990153A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to a rudder structure, and more particularly to a friction device for suppressing adverse vibrations of the rudder. Background Technology
[0002] To address undesirable oscillations and vibrations generated by the rudder (such as limiting cycle oscillations, a typical self-excited vibration and a complex and important problem in nonlinear autonomous systems theory, characterized by constant amplitude and periodicity), the rudder system clearance is typically controlled within a small range. For example, some fighter jets control the rudder system clearance within 0.5°. This method has two main drawbacks: 1. Controlling the rudder system clearance places high demands on the entire rudder system structure and related equipment (such as servo motors), resulting in high design and manufacturing costs; 2. As the rudder is used, the clearance increases, increasing the possibility of undesirable rudder oscillations and vibrations, leading to high maintenance costs and inconvenience. Summary of the Invention
[0003] The purpose of this invention is to reduce the cost of designing and manufacturing related structures and equipment of the rudder system, and to suppress adverse oscillations and vibrations generated by the rudder when the rudder system clearance is large (e.g., greater than 0.5°), while reducing the cost of use and maintenance.
[0004] This invention is achieved through the following technical solutions: A friction component device for suppressing adverse vibrations of a rudder includes an upper rotating component, a lower fixed base, and a semi-enclosed fixing component; The upper rotating component includes a rotating support fixing ring 2, a rotating support 3, and a metal friction head 4. One end of the rotating support 3 is fixedly connected to the rudder shaft through the rotating support fixing ring 2, and the other end is fixedly connected to the metal friction head 4. The lower fixed base includes a friction plate 5, a friction plate cover plate 6, a slider 7, a fixed base slide rail 8, and a fixed base mounting ring 9. The fixed base slide rail 8 is fixedly connected to the rudder shaft seat through the fixed base mounting ring 9. The slider 7 is slidably mounted on the fixed base slide rail 8. The friction plate 5 is fixedly mounted on the front end of the slider 7 through the friction plate cover plate 6 and contacts the metal friction head 4. The slider 7, the fixed base slide rail 8, and the fixed base mounting ring 9 are connected by long screws, and their relative positions are adjustable.
[0005] Furthermore, the fixed base mounting ring 9 and the fixed base slide rail 8 are equipped with mounting lugs, and bolts pass through the mounting lugs to secure the two together.
[0006] Furthermore, the mounting lugs of the fixed base mounting ring 9 and the fixed base slide rail 8 are also provided with holes for the long screws to pass through. The long screws pass through the holes on the mounting lugs and the holes on the slider 7 to connect the fixed base mounting ring 9, the fixed base slide rail 8 and the slider 7.
[0007] Furthermore, the slider 7 is an L-shaped plate, and the base plate of the L-shaped plate cooperates with the fixed base slide rail 8. The base plate has two lateral threaded through holes, and the fixed base slide rail 8 has two elongated holes on each side, which cooperate with the lateral threaded through holes of the L-shaped plate base plate to achieve screw connection and fixation and help to adjust the position of the slider 7.
[0008] Furthermore, a semi-enclosed fastener 1, which serves to prevent loosening, is also connected between the upper rotating component and the rudder shaft.
[0009] The beneficial effects of this invention are: 1. The principle is simple, installation is relatively easy, and the impact on the overall airframe is minimal. This friction component weighs less than 500g and is installed inside the lower fairing of the vertical stabilizer, thus not affecting the aircraft's aerodynamic performance. Its impact on flight performance is only slightly manifested as an increase in the aircraft's empty weight. Therefore, it has virtually no effect on the aircraft's flight performance.
[0010] 2. Significantly reduces the design and manufacturing costs of structures and equipment required to control the clearance of the rudder system. The manufacturing cost of a set of rudder friction components is less than 20,000, while the cost of using high-precision servos or improving the rudder system structure may be hundreds of thousands to millions. 3. Through durability tests, the friction device showed very low wear after prolonged use and minimal performance degradation. Calculations and analysis showed that the service life of the friction components was much longer than that of the main body, demonstrating strong durability, long device life, and reliable use.
[0011] 4. The usage and maintenance costs are very low. Based on actual usage, no adjustment of the friction device is required within 2 years after the installation of this friction component, and the rudder with the friction component installed will no longer produce adverse oscillations or vibrations. Attached Figure Description
[0012] Figure 1 This is a schematic diagram illustrating the principle of the present invention for suppressing adverse vibrations of the rudder; Figure 2 This is a schematic diagram of the structure of the present invention. Detailed Implementation
[0013] like Figure 1 As shown, the principle of this invention is to increase the damping of the rudder system by adding a frictional torque to the rudder shaft, using the frictional torque to balance the inertial torque generated when the rudder produces a limiting cycle oscillation. The frictional torque M provided by the friction component... friction Similar to the maximum torque generated by the inertial force during rudder vibration, the inertial torque can be calculated using the following formula: , of which M friction For frictional torque, F inertiaLet be the inertial force during rudder rotation, m be the rudder mass, a be the acceleration at the rudder's center of mass, and l be the distance from the rudder's center of mass to the axis of rotation. Angular acceleration, This is the moment of inertia of the rudder. Its maximum value occurs at the position where the vibration amplitude angular acceleration is the largest.
[0014] The present invention adds a friction element at the rudder shaft. By adjusting the friction element, different friction torques are provided to the rudder, thereby suppressing the adverse oscillations and vibrations of the rudder.
[0015] like Figure 2 The diagram shown is a structural diagram of the present invention.
[0016] The friction component consists of three parts: an upper rotating component, a lower fixed base, and a semi-enclosed fixing component.
[0017] The upper rotating component includes a rotating support fixing ring 2, a rotating support 3, and a metal friction head 4. The rotating support 3 is connected to and fixed to the rudder shaft via the rotating support fixing ring 2, and the upper rotating component is fixedly connected to the metal friction head 4. When the rudder rotates, the rotating component on the metal friction head 4, together with the rudder, performs circular motion at the same frequency around the rudder shaft.
[0018] The semi-enclosed fastener 1 is an anti-loosening structure connecting the upper rotating component and the rudder shaft. This structure can be selected for installation or not depending on the actual usage.
[0019] The lower fixed base includes a friction plate 5, a friction plate cover plate 6, a slider 7, a fixed base slide rail 8, and a fixed base mounting ring 9. The fixed base slide rail 8 is connected to and fixed to the rudder shaft seat via the fixed base mounting ring 9. The slider 7 is mounted on the fixed base slide rail 8, and the friction plate 5 is fixedly mounted on the front end of the slider 7 via the friction plate cover plate 6. Two long screws on both sides of the lower fixed base connect the front end of the slider 7 to the mounting lugs of the fixed base slide rail 8 and the fixed base mounting ring 9. By turning the two long screws, the forward and backward position of the slider 7 on the slide rail can be adjusted. When the rudder is rotated, it causes the upper and lower parts of this friction component to move relative to each other, causing friction between the friction plate 5 and the metal friction head 4. By adjusting the front and rear position of the slider 7 in the fixed base slide rail 8, the pressure of the friction plate 5 on the metal friction head 4 can be changed, thereby changing the friction torque generated by the friction component when the metal friction head 4 contacts the friction plate 5.
[0020] There are two elongated holes on both sides of the fixed base slide rail 8. When the friction torque needs to be adjusted, loosen the fixing screw that passes through the elongated hole and the through hole at the bottom of the slider 7, move the position of the slider 7, and adjust the pressure between the metal friction head 4 and the friction plate 5 until the friction torque reaches the required value. The adjustment of the slider 7 position is finished. Tighten the fixing screw to fix the position of the slider 7 and maintain the stability of the friction torque.
Claims
1. A friction component device for suppressing adverse vibrations of a rudder, characterized in that: It includes an upper rotating component, a lower fixed base, and a semi-enclosed fixing component; the upper rotating component includes a rotating support fixing ring (2), a rotating support (3), and a metal friction head (4). One end of the rotating support (3) is fixedly connected to the rudder shaft through the rotating support fixing ring (2), and the other end is fixedly connected to the metal friction head (4); the lower fixed base includes a friction plate (5), a friction plate cover plate (6), a slider (7), a fixed base slide rail (8), and a fixed base mounting ring (9). The fixed base slide rail (8) is fixedly connected to the rudder shaft seat through the fixed base mounting ring (9). The slider (7) is slidably mounted on the fixed base slide rail (8). The friction plate (5) is fixedly mounted on the front end of the slider (7) through the friction plate cover plate (6) and contacts the metal friction head (4). The slider (7), the fixed base slide rail (8), and the fixed base mounting ring (9) are connected by long screws, and their relative positions are adjustable.
2. The friction component device for suppressing adverse vibrations of the rudder according to claim 1, characterized in that: The fixed base mounting ring (9) and the fixed base slide rail (8) are equipped with mounting lugs, and bolts pass through the mounting lugs to fix the two together.
3. The friction component device for suppressing adverse vibrations of the rudder according to claim 2, characterized in that: The mounting lugs of the fixed base mounting ring (9) and the fixed base slide rail (8) are also provided with holes for the long screw to pass through. The long screw passes through the holes on the mounting lugs and the holes on the slider (7) to connect the fixed base mounting ring (9), the fixed base slide rail (8) and the slider (7).
4. The friction component device for suppressing adverse vibrations of the rudder according to claim 1, characterized in that: The slider (7) is an L-shaped plate. The base plate of the L-shaped plate and the fixed base slide rail (8) are matched. There are two lateral threaded through holes on the base plate. There are two elongated holes on both sides of the fixed base slide rail (8), which are matched with the lateral threaded through holes on the base plate of the L-shaped plate to achieve screw connection and help to adjust the position of the slider (7).
5. The friction component device for suppressing adverse vibrations of the rudder according to claim 1, characterized in that: A semi-enclosed fastener (1) is also connected between the upper rotating component and the rudder shaft to prevent loosening.