A structure of an angular displacement measuring element based on a flexible connection

Abstract

The application discloses a kind of angular displacement measurement element structures based on flexible connection, belong to the field of force and torque precision measurement in aerodynamic test, including: angular displacement measurement unit, and the front end of the front end is processed with front end flexible connection section, and the front end of front end flexible connection section is processed with front end mounting base;Angular displacement measurement unit is pasted with strain gauge;Angular displacement measurement unit is processed with rear end flexible connection section at rear end, and the rear end of rear end flexible connection section is processed with rear end mounting base.The application uses flexible connection structure, effectively buffers the vibration and pneumatic load in the measurement process, avoids the stress concentration and data distortion caused by rigid connection, greatly improves the stability of angular displacement measurement element, structure is simple, high integration, strong practicability, can be directly applied to angular displacement accurate measurement scene, especially suitable for the occasion with high requirements for measurement stability and anti-interference, significantly improves the accuracy and reliability of angular displacement measurement, reduces installation and use cost.

Description

Technical Field

[0001] This invention belongs to the field of precision force and torque measurement technology in aerodynamic testing. More specifically, this invention relates to a structure for an angular displacement measuring element based on a flexible connection. The invention is applicable to the precise detection of the pitch angular displacement of a test model or experimental device in pitch dynamic derivative tests of high- and low-speed aircraft. Background Technology

[0002] In recent years, the precision requirements for the measurement of various physical quantities have been continuously increasing in the fields of modern precision manufacturing, dynamic working condition monitoring, and aerospace precision measurement. In the dynamic derivative test of aircraft, factors such as load on the test model, mechanical vibration, installation deviation, and deformation of measuring elements can easily lead to rigid impact, axis misalignment, or unstable contact between the test model and the test device, which in turn causes distortion and increased error in the relative angular displacement measurement data, and may even damage the displacement measuring elements and test device.

[0003] Existing pitch derivative testing devices mostly employ rigid connection structures for angular displacement measurement elements. While this ensures structural strength at the connection points, such structures are prone to stress concentration under complex operating conditions, reducing the device's lifespan. Consequently, their load-bearing capacity is insufficient, failing to effectively address the problem of accurate angular displacement measurement under strong aerodynamic loads. Some existing technologies attempt to introduce flexible connection elements, but these cannot effectively buffer angular measurement interference from aerodynamic loads. Furthermore, they suffer from poor positioning accuracy and limited adaptability of flexible components, failing to simultaneously meet the dual requirements of flexible buffering and precise measurement, ultimately failing to satisfy the demands of high-precision measurement scenarios.

[0004] For the reasons mentioned above, developing a flexible connection angular displacement measuring element structure that can effectively buffer vibration, has a self-compensation function for deviation, and ensures measurement accuracy and stability has become a technical problem that urgently needs to be solved by those skilled in the art. Summary of the Invention

[0005] One object of the present invention is to solve at least the above-mentioned problems and / or defects, and to provide at least the advantages described below.

[0006] To achieve these and other advantages according to the present invention, a flexible connection-based angular displacement measuring element structure is provided, comprising: An angular displacement measuring unit has a front flexible connecting section processed at its front end, and a front mounting base processed at the front end of the front flexible connecting section; strain gauges are attached to the angular displacement measuring unit. The rear end of the angular displacement measuring unit is machined with a rear flexible connecting section, and the rear end of the rear flexible connecting section is machined with a rear mounting base.

[0007] Preferably, the front-end mounting base, the front-end flexible connecting section, the angular displacement measuring unit, the rear-end flexible connecting section, and the rear-end mounting base are manufactured using an integrated molding process.

[0008] Preferably, the material of the angular displacement measuring element structure based on flexible connection is 250-grade maraging steel F141.

[0009] Preferably, the strain gauge is a resistance strain gauge or a metal foil strain gauge.

[0010] Preferably, the structure of the front flexible connection segment includes: The first arc segment has its front end connected to the front end mounting base; The first I-shaped beam has its front end connected to the first arc segment, and its rear end connected to the angular displacement measuring unit; the two sides of the first I-shaped beam have an arc structure.

[0011] Preferably, the structure of the rear flexible connection segment includes: The second I-shaped beam has its front end connected to the angular displacement measuring unit; The second arc segment has its front end connected to the second I-shaped beam, and its rear end connected to the rear mounting base; the two sides of the second I-shaped beam have an arc structure.

[0012] Preferably, the flexibility deformation coefficients of the front flexible connecting segment and the rear flexible connecting segment are greater than those of the angular displacement measuring unit, the front mounting base, and the rear mounting base.

[0013] Preferably, the front mounting base and the rear mounting base are provided with mounting screw holes.

[0014] Preferably, the angular displacement of the angular displacement measuring element structure and the deformation of the angular displacement measuring unit exhibit a single linear relationship.

[0015] The present invention has at least the following beneficial effects: The present invention provides an angular displacement measuring element structure based on flexible connection. By optimizing the design of the flexible connection structure, a flexible and adaptable connection of the test balance, displacement element and support base is achieved, which solves the technical defects of traditional rigid or other connection-based angular displacement measuring elements, such as poor anti-interference ability, short service life and easy damage. At the same time, it improves the accuracy, service life and adaptability of the measuring element's angular displacement measurement.

[0016] The angular displacement measuring element structure based on flexible connection of the present invention has strong anti-interference ability: the flexible connection structure effectively buffers the vibration and aerodynamic load during the measurement process, avoids stress concentration and data distortion caused by rigid connection, and greatly improves the stability of angular displacement measuring element.

[0017] The angular displacement measuring element structure based on flexible connection of the present invention has high measurement accuracy: through the precise positioning of the front and rear structural fixing grooves, the angular displacement measuring unit measures the relative angular displacement between the front vibration mechanism and the support rod in real time. The arc structure set on the front and rear flexible connection sections can also compensate for the small axial and radial deviations during installation and measurement. Its ultimate purpose is to eliminate the influence of lateral aerodynamic load on angular displacement measurement, ensure the accuracy of real-time angular displacement, effectively reduce measurement error, and meet the requirements of high-precision measurement.

[0018] The angular displacement measuring element structure based on flexible connection of the present invention is made of martensitic aging steel F141 (250 grade), which combines the strength of the material structure with the flexibility of the design structure, and has good fatigue resistance. At the same time, the angular displacement measuring unit can be flexibly designed with specific dimensions according to working conditions. The angular displacement measuring element structure is suitable for a variety of measurement scenarios and has a long service life.

[0019] The angular displacement measuring element based on flexible connection of the present invention has high structural safety and practicality: the deformation of the angular displacement measuring unit is limited by the pitch dynamic guide mechanism, avoiding the damage to the element caused by excessive deformation due to the "one end fixed and one end free" connection form, effectively protecting the angular displacement measuring element, improving structural safety, and can be widely used in the development of pitch dynamic derivative test device, with good practicality and promotion value.

[0020] Other advantages, objectives and features of the present invention will become apparent in part from the following description, and in part from those skilled in the art through study and practice of the invention. Attached Figure Description

[0021] Figure 1 This is a schematic diagram of the angular displacement measuring element structure based on flexible connection in Example 1; Figure 2 This is a schematic diagram of the connection of an angular displacement measuring element structure based on flexible connections; Figure 3 This is a schematic diagram illustrating the working principle of an angular displacement measuring element structure based on a flexible connection.

[0022] The corresponding labels for each structure are as follows: front-end mounting base 1, front-end flexible connection section 2, angular displacement measuring unit 3, rear-end flexible connection section 4, rear-end mounting base 5, vibration mechanism 6, angular displacement measuring element structure 7, support rod 8, first arc segment 21, first I-beam 22, second arc segment 41, second I-beam 42, mounting screw hole 9. Detailed Implementation

[0023] The present invention will now be described in further detail with reference to the accompanying drawings, so that those skilled in the art can implement it based on the description.

[0024] It should be understood that terms such as “having,” “comprising,” and “including” as used herein do not exclude the presence or addition of one or more other elements or combinations thereof.

[0025] Example like Figure 1 As shown, an angular displacement measuring element structure based on a flexible connection is characterized by comprising: The angular displacement measuring unit 3 adopts a single rectangular beam structure. The front end of the angular displacement measuring unit 3 is processed with a front flexible connecting section 2, and the front end of the front flexible connecting section 2 is processed with a front mounting base 1. The angular displacement measuring unit 3 is attached with a resistance strain gauge or a metal foil strain gauge. The outer surface of the resistance strain gauge or the metal foil strain gauge is completely attached to the angular displacement measuring unit 3 without gaps, so as to sense the deformation of the component in real time and not be affected by assembly stress. The rear end of the angular displacement measuring unit 3 is machined with a rear flexible connecting section 4, and the rear end of the rear flexible connecting section 4 is machined with a rear mounting base 5; the front mounting base 1 and the rear mounting base 5 are respectively provided with two mounting screw holes 9. Among them, the front mounting base 1, the front flexible connecting section 2, the angular displacement measuring unit 3, the rear flexible connecting section 4, and the rear mounting base 5 are made of 250-grade martensitic aging steel F141 using an integrated molding process, which combines material structural strength and design structural flexibility, and has good fatigue resistance. The flexible deformation coefficients of the front flexible connecting section 2 and the rear flexible connecting section 4 are greater than those of the angular displacement measuring unit 3, the front mounting base 1, and the rear mounting base 5; the angular displacement of the angular displacement measuring element 3 structure and the deformation of the angular displacement measuring unit 3 exhibit a single linear relationship.

[0026] The structure of the front flexible connection segment 2 includes: The first arc segment 21 has its front end connected to the front end mounting base 1; The first I-shaped beam 22 has its front end connected to the first arc segment 21, and its rear end connected to the angular displacement measuring unit 3; the two sides of the first I-shaped beam 22 have an arc structure.

[0027] The structure of the rear flexible connection segment 4 includes: The second I-shaped beam 42 has its front end connected to the angular displacement measuring unit; The second arc segment 41 has its front end connected to the second I-shaped beam 42, and its rear end connected to the rear end mounting base 5; the two sides of the second I-shaped beam 42 have an arc structure.

[0028] like Figure 2 and Figure 3 As shown, in this embodiment, during installation, the front mounting base 1 is used to fix the front end of the angular displacement measuring element structure 7 based on the flexible connection. The front mounting base 1 is mechanically limited by the fixing groove of the vibration mechanism 6. The fixing groove is fitted on the outside of the front mounting base 1 to provide directional guidance for the front fixed end of the angular displacement measuring unit 3, avoid radial offset of the front mounting base 1, limit the deformation of the angular displacement measuring unit 3, and fix the front mounting base 1 to the free end of the vibration mechanism of the pitch motion derivative device with two M5 bolts. Figure 3 In the figure, δ1 is the angle between the axis of the vibration mechanism 6 and the axis of the angular displacement measuring element structure 7, and δ2 is the angle between the axis of the support rod 8 and the axis of the angular displacement measuring element structure 7.

[0029] The rear mounting base 5 is used for the rear-end fixed installation of the angular displacement measuring element structure 7 based on flexible connection. Mechanical limiting is achieved by the fixing groove of the support rod 8, which is fitted onto the outside of the rear mounting base. This provides directional guidance for the rear fixed end of the angular displacement measuring element 3, preventing radial offset of the rear mounting base 5 and limiting the deformation of the angular displacement measuring unit 3. Simultaneously, the rear mounting base 5 is fixedly connected to the front end of the support rod 8 of the pitch derivative device using bolts at both ends. The aforementioned installation method of the front mounting base 1 and the rear mounting base 5 prevents excessive deformation from affecting measurement accuracy and service life, ensuring the rigid transmission accuracy of the measurement path.

[0030] The front flexible connecting section 2 and the rear flexible connecting section 4 are respectively set between the front mounting base 1, the rear mounting base 5 and the angular displacement measuring unit 3. They can not only buffer mechanical vibration and external impact force, but also compensate for small axial and radial deviations during the measurement process, and eliminate errors caused by aerodynamic loads in angular displacement measurement. Since the flexible deformation coefficients of the front flexible connecting section 2 and the rear flexible connecting section 4 are greater than those of other rigid connecting parts, four sets of circular arc flexible hinges composed of the first I-shaped beam 22 and the second I-shaped beam 42 are evenly arranged along the axial direction of the front flexible connecting section 2 and the rear flexible connecting section 4, allowing the angular displacement measuring unit 3 to undergo slight elastic deformation along a preset direction.

[0031] The working principle of the angular displacement measuring element structure based on flexible connection in this embodiment is as follows: During the process of aerodynamic load and small-angle vibration, the front flexible connecting section 2 and the rear flexible connecting section 4 work together to buffer mechanical vibration and the impact force of external aerodynamic load. The four sets of circular arc structures of the first I-beam 22 and the second I-beam 42 compensate for minor deviations caused by installation and measurement in real time, avoiding measurement errors caused by external loads on angular displacement measurement. Simultaneously, driven by the motor, the vibration mechanism 6 deflects around the rotation center, which is the axis of the support rod 8. Since one end of the angular displacement measuring element structure 7 based on flexible connection is fixedly connected to the vibration mechanism 6 and the other end is fixedly connected to the support rod 8, the rotation angle between the vibration mechanism 5 and the support rod 8 can be calculated by attaching resistance strain gauges or metal foil strain gauges at different positions of the angular displacement measuring unit. In this embodiment, the angular displacement measuring element structure 7 based on flexible connection is symmetrically arranged horizontally and longitudinally about the pitch guide device in the overall spatial layout, making it insensitive to longitudinal aerodynamic loads and effectively eliminating the influence of longitudinal aerodynamic loads on angular displacement measurement.

[0032] The angular displacement measuring element structure based on flexible connection of this embodiment is applied to a pitch dynamic derivative test device. Its design loads are: normal force Y component of 15000 N, pitch moment Mz component of 800 N·m, roll moment Mx component of 1000 N·m, lateral force Z component of 15000 N, and yaw moment My component of 800 N·m. That is, under the combined action of the above loads, compared with the displacement measurement distortion of traditional connected structure angular displacement elements, the angular displacement measuring element structure based on flexible connection of this embodiment is not affected by the combined load and can achieve accurate real-time angular displacement measurement.

[0033] The number of devices and processing scale described herein are for the purpose of simplifying the description of the invention. Applications, modifications, and variations of the invention will be readily apparent to those skilled in the art.

[0034] Although embodiments of the present invention have been disclosed above, they are not limited to the applications listed in the specification and embodiments. They can be applied to various fields suitable for the present invention. For those skilled in the art, other modifications can be easily made. Therefore, without departing from the general concept defined by the claims and their equivalents, the present invention is not limited to the specific details and illustrations shown and described herein.

Claims

1. A structure for an angular displacement measuring element based on a flexible connection, characterized in that, include: An angular displacement measuring unit has a front flexible connecting section processed at its front end, and a front mounting base processed at the front end of the front flexible connecting section; strain gauges are attached to the angular displacement measuring unit. The rear end of the angular displacement measuring unit is machined with a rear flexible connection section, and the rear end of the rear flexible connection section is machined with a rear mounting base. The structure of the front-end flexible connection segment includes: The first arc segment has its front end connected to the front end mounting base; The first I-shaped beam has its front end connected to the first arc segment, and its rear end connected to the angular displacement measuring unit; the two sides of the first I-shaped beam have an arc structure. The structure of the rear flexible connection segment includes: The second I-shaped beam has its front end connected to the angular displacement measuring unit; The second arc segment has its front end connected to the second I-shaped beam, and its rear end connected to the rear mounting base; the two sides of the second I-shaped beam have an arc structure.

2. The angular displacement measuring element structure based on flexible connection as described in claim 1, characterized in that, The front-end mounting base, front-end flexible connecting section, angular displacement measuring unit, rear-end flexible connecting section, and rear-end mounting base are all manufactured using an integrated molding process.

3. The angular displacement measuring element structure based on flexible connection as described in claim 1, characterized in that, The angular displacement measuring element structure based on flexible connection is made of 250-grade martensitic aging steel F141.

4. The angular displacement measuring element structure based on flexible connection as described in claim 1, characterized in that, The strain gauge is a resistance strain gauge or a metal foil strain gauge.

5. The angular displacement measuring element structure based on flexible connection as described in claim 1, characterized in that, The flexible deformation coefficients of the front flexible connecting section and the rear flexible connecting section are greater than those of the angular displacement measuring unit, the front mounting base, and the rear mounting base.

6. The angular displacement measuring element structure based on flexible connection as described in claim 1, characterized in that, The front-end mounting base and the rear-end mounting base are provided with mounting screw holes.

7. The angular displacement measuring element structure based on flexible connection as described in claim 1, characterized in that, The angular displacement of the angular displacement measuring element structure and the deformation of the angular displacement measuring unit exhibit a single linear relationship.

Images