Intelligent adaptive fixture for ampt multi-size specimen dynamic modulus testing

Abstract

The application provides an intelligent adaptive clamp for AMPT multi-size test piece dynamic modulus testing, comprising a base, a vertical support assembly, a pressing assembly, a sensing assembly and a central control unit; the vertical support assembly is arranged on the base; the pressing assembly is installed on the vertical support assembly in a liftable manner, and the pressing assembly comprises a main pressing disc, a floating contact disc and an elastic support; the sensing assembly comprises a displacement sensor and a plurality of pressure sensors; the displacement sensor is used for detecting the displacement position of the main pressing disc; the plurality of pressure sensors are used for detecting the multi-point pressure values between the main pressing disc and the elastic support; and the central control unit is in communication connection with the displacement sensor and the pressure sensors respectively. The intelligent adaptive clamp for AMPT multi-size test piece dynamic modulus testing provided by the application can compensate and adjust according to the multi-point pressure differences after the test piece is contacted in the initial pressing stage.

Description

Technical Field

[0001] This application belongs to the technical field of specimen testing equipment, specifically relating to an intelligent adaptive fixture for dynamic modulus testing of multi-size AMPT specimens. Background Technology

[0002] Dynamic modulus is an important indicator for evaluating the high-temperature stability, deformation resistance and mechanical response characteristics of asphalt mixtures. As a commonly used standard specimen, the dynamic modulus test results of AMPT (Asphalt Mixture Performance Tester) specimens are of great significance for the performance analysis of road materials.

[0003] Existing fixtures for testing the dynamic modulus of Marshall specimens mostly employ fixed-height or limited-stroke adjustment structures, making it difficult to accommodate different specimen sizes and height deviations caused by molding processes and gradation differences, resulting in insufficient adaptability. Existing adjustable fixtures generally rely on manual bolts and knobs for clamping, making the adjustment process cumbersome and difficult to guarantee the coaxiality between the upper and lower clamping components and the uniformity of stress on the specimen contact surface, easily causing localized stress concentrations and affecting test accuracy and repeatability.

[0004] Existing fixtures are mostly simple mechanical structures, lacking real-time sensing and feedback of key parameters such as displacement, clamping force, and locking status. They cannot achieve quantitative monitoring of the clamping process, nor can they link with the testing system for data, and cannot provide timely feedback of experimental data for timely adjustments, resulting in a lag. Summary of the Invention

[0005] This application provides an intelligent adaptive fixture for dynamic modulus testing of multi-size specimens in AMPT, aiming to solve the problems of fixed height of existing fixtures, which are mostly purely mechanical structures, resulting in poor compatibility between the fixture and the specimen, low clamping accuracy, and insufficient intelligent monitoring.

[0006] To achieve the above objectives, the technical solution adopted in this application is as follows: A smart adaptive fixture for dynamic modulus testing of multi-size AMPT specimens is provided, comprising: Base; A vertical support assembly is mounted on the base; The pressing assembly is vertically mounted on the vertical support assembly and located above the base. The pressing assembly includes a main pressing plate, a floating contact plate located below the main pressing plate, and an elastic support member disposed between the main pressing plate and the floating contact plate. The sensing assembly includes a displacement sensor and multiple pressure sensors. The displacement sensor detects the displacement position of the main pressure plate, and the multiple pressure sensors are evenly distributed between the main pressure plate and the elastic support member to detect multi-point pressure values ​​between them. The central control unit is communicatively connected to both the displacement sensor and the pressure sensor. The central control unit is configured as follows: Control the descent of the holding assembly; When the reading of at least one of the pressure sensors reaches a preset contact threshold, it is determined that the floating contact plate has contacted the specimen; After contact is determined, the main pressure plate is controlled to descend based on the difference in readings of all the pressure sensors. Through the differential compression of the elastic support, the floating contact plate adaptively tilts or shifts until the difference in readings is less than a preset uniformity threshold.

[0007] In one possible implementation, the vertical support component includes: Multiple support rods are spaced apart circumferentially along the base; the bottom end of each support rod is connected to the base, and the top end of each support rod slides through the floating contact plate and the main pressure plate; and Multiple sliding rings are slidably sleeved on the outer periphery of the corresponding support rods and located between the floating contact plate and the base. Each sliding ring is connected to the main pressure plate.

[0008] In one possible implementation, the sliding ring is driven by a drive member, which drives the sliding ring to move up and down along the axial direction of the corresponding support rod.

[0009] In one possible implementation, the sliding ring is provided with an electromagnetic locking structure, which has a locking part that cooperates with the support rod. After the pressing assembly reaches a preset position, the locking part abuts against the support rod to restrict the sliding ring from moving up and down along the support rod.

[0010] In one possible implementation, the elastic support includes a plurality of elastic elements arranged in a circumferential array along the main pressure plate, the elastic elements having a preload force that pushes the floating contact plate away from the main pressure plate.

[0011] In one possible implementation, the holding component further includes: A connecting sleeve is fitted around the outer periphery of both the main pressure plate and the floating contact plate. The connecting sleeve, the main pressure plate, and the floating contact plate together form the installation space for the elastic support member.

[0012] In one possible implementation, the bottom surface of the floating contact plate and the top surface of the base are respectively provided with wear-resistant layers.

[0013] In one possible implementation, the displacement sensor includes a detection element and a reading section, the detection element extending axially along the support rod, and the reading section connected to the main pressure plate to detect the relative position of the main pressure plate relative to the base.

[0014] In one possible implementation, the intelligent adaptive fixture for dynamic modulus testing of AMPT multi-size specimens further includes a laser guide disposed on the base and facing the specimen placement area, the laser guide being used to indicate the installation position of the specimen relative to the base.

[0015] In one possible implementation, the central control unit is provided with a communication interface and a display unit. The communication interface is used to connect with the dynamic modulus testing system, and the display unit is used to display the displacement value detected by the displacement sensor and the multi-point pressure value detected by the pressure sensor.

[0016] The intelligent adaptive fixture for dynamic modulus testing of AMPT multi-size specimens provided in this application, compared with the prior art, enables the fixture to identify whether the specimen is in contact at the initial stage of clamping through the coordinated cooperation of the main pressure plate, floating contact plate, elastic support, displacement sensor, pressure sensor and central control unit, and to make compensatory adjustments based on the pressure difference at multiple points after contact. This allows for adaptive clamping of AMPT specimens of different heights, sizes and with uneven end faces and slight placement eccentricity.

[0017] This structure can effectively reduce local pre-contact, local suspension and stress concentration, making the specimen more uniformly compressed, improving the clamping alignment and stability, reducing reliance on manual adjustment, avoiding test errors caused by clamping misalignment in traditional mechanical fixtures, and improving the stability and alignment of specimen clamping.

[0018] Based on pressure and displacement sensors, the clamping status can be detected, adjusted, and locked, improving the stability and automation of dynamic modulus testing. Attached Figure Description

[0019] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0020] Figure 1This is a front view schematic diagram of an intelligent adaptive fixture for dynamic modulus testing of multi-size specimens using AMPT, provided in an embodiment of this application. The driving component is not shown in the figure. Figure 2 This is a schematic diagram of the structure of an intelligent adaptive fixture for dynamic modulus testing of multi-size specimens in AMPT according to an embodiment of this application. The L-shaped connecting plate and the driving component are not shown in the figure. Figure 3 This is a schematic diagram of the structure of the pressing component used in an embodiment of this application; Figure 4 This is a schematic cross-sectional view of the assembly of the elastic support member and the pressure sensor in a pressure-holding assembly used in an embodiment of this application; Figure 5 This is a schematic diagram of the extension path of the detection element of the displacement sensor in a pressing assembly used in an embodiment of this application; Figure 6 A front view schematic diagram of an intelligent adaptive fixture for dynamic modulus testing of multi-size specimens using AMPT provided in an embodiment of this application; Figure 7 This is a front view schematic diagram of an intelligent adaptive fixture for dynamic modulus testing of multi-size specimens using AMPT, provided as another embodiment of this application.

[0021] Explanation of reference numerals in the attached figures: 1. Base; 2. Pressing assembly; 21. Main pressure plate; 22. Floating contact plate; 23. Elastic support component; 231. Elastic component; 24. Connecting sleeve; 3. Vertical support assembly; 31. Support rod; 32. Sliding ring; 33. L-shaped connecting plate; 34. Driving component; 4. Electromagnetic locking structure; 5. Displacement sensor; 6. Pressure sensor; 7. Central control unit; 71. Communication interface; 72. Display unit; 8. Wear-resistant layer; 9. Laser guide. Detailed Implementation

[0022] To make the technical problems, technical solutions, and beneficial effects to be solved by this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and are not intended to limit the scope of this application.

[0023] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of them. The following description of at least one exemplary embodiment is actually illustrative only and is in no way intended to limit this application or its application or use. All other embodiments obtained by those skilled in the art based on the embodiments of this application without creative effort are within the scope of protection of this application.

[0024] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the exemplary embodiments according to this application. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0025] It should also be noted that, unless otherwise explicitly specified and limited, terms such as "installation," "connection," "linking," "fixing," and "setting" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0026] Please refer to the following: Figures 1 to 7The present application describes the intelligent adaptive fixture for dynamic modulus testing of AMPT multi-size specimens. The intelligent adaptive fixture for dynamic modulus testing of AMPT multi-size specimens includes a base 1, a vertical support assembly 3, a holding assembly 2, a sensing assembly, and a central control unit 7. A vertical support assembly 3 is mounted on a base 1. A pressing assembly 2 is vertically mounted on the vertical support assembly 3 and is located above the base 1. The pressing assembly 2 includes a main pressure plate 21, a floating contact plate 22 located below the main pressure plate 21, and an elastic support member 23 located between the main pressure plate 21 and the floating contact plate 22. A sensing assembly includes a displacement sensor 5 and multiple pressure sensors 6. The displacement sensor 5 is used to detect the displacement position of the main pressure plate 21, and the multiple pressure sensors 6 are evenly distributed between the main pressure plate 21 and the elastic support member 23 to detect the multi-point pressure values ​​between the two. A central control unit 7 is communicatively connected to the displacement sensor 5 and the pressure sensors 6 respectively. The central control unit 7 is configured to: control the pressing assembly 2 to descend; when the reading of at least one pressure sensor 6 reaches a preset contact threshold, determine that the floating contact plate 22 has contacted the specimen; after determining contact, based on the difference in readings of all pressure sensors 6, control the main pressure plate 21 to descend, and through the differential compression of the elastic support member 23, make the floating contact plate 22 adaptively tilt or displace until the difference in readings is less than a preset uniformity threshold.

[0027] It should be noted that the compensating tilt refers to the fact that after the holding component 2 contacts the specimen, the central control unit 7 controls the main pressure plate 21 to continue moving downward based on the multi-point pressure distribution differences detected by multiple pressure sensors 6, so that the elastic support 23 between the main pressure plate 21 and the floating contact plate 22 forms a non-uniform compression state, thereby driving the floating contact plate 22 to adaptively tilt, deflect or locally displace relative to the main pressure plate 21, in order to compensate for unevenness of the specimen end face, specimen height error, installation eccentricity or local contact.

[0028] Compensatory tilting does not require a significant drop in the main pressure plate 21, but rather a minute adjustment process aimed at achieving pressure equilibrium at multiple points on the contact surface. This adjustment can be completed in a single step or in iterative steps. The central control unit 7 can determine the current uniformity of force based on parameters such as the pressure difference, pressure gradient distribution, difference between the maximum and minimum values, and deviation of the average value or standard deviation of each pressure sensor 6, and output corresponding adjustment commands until the pressure difference at each detection point is less than a preset uniformity threshold.

[0029] It should be noted that the preset contact threshold is a pressure criterion used to determine whether the floating contact plate 22 has formed effective contact with the specimen. When the reading of at least one pressure sensor 6 reaches this threshold, it can be considered that the floating contact plate 22 has contacted the specimen surface, and the subsequent pressure equalization adjustment process can be triggered. The contact threshold should be set according to the range of the pressure sensor 6, the system noise level, the weight of the holding assembly 2, the material characteristics of the specimen, the vibration conditions of the test environment, and the desired contact sensitivity.

[0030] It should be noted that the preset uniformity threshold is a control criterion used to determine whether the contact pressure distribution reflected by multiple pressure sensors 6 has reached the expected balanced state. The uniformity threshold can be set based on the difference between the maximum and minimum pressure values ​​at each detection point, the difference between adjacent points, the standard deviation, the coefficient of variation, the average deviation, or the normalized error. When the difference between the pressure values ​​at multiple points is less than this threshold, it can be considered that the floating contact plate 22 and the end face of the specimen have formed a relatively uniform pressing contact state.

[0031] It should be noted that the multi-point pressure value refers to the local pressure data detected by multiple pressure sensors 6 distributed between the main pressure plate 21 and the floating contact plate 22 during the clamping process. The multi-point pressure value can be a real-time instantaneous value, or an effective value after filtering, averaging, or dynamic compensation processing.

[0032] Specifically, the central control unit 7 can be implemented using a programmable logic controller (PLC), industrial controller, microcontroller, embedded processor, industrial control motherboard, motion controller, or other electronic control equipment with data acquisition, logic judgment, and execution control capabilities. It can be implemented using a combination of a PLC and a touch screen.

[0033] Optionally, the pressure sensor 6 can be any one of a thin-film pressure sensor, a strain gauge pressure sensor, or a piezoelectric pressure sensor.

[0034] Optionally, the displacement sensor 5 can be any one of a linear displacement sensor, a grating ruler, a laser displacement sensor, or a magnetostrictive displacement sensor.

[0035] Specifically, the elastic support 23 is a spring, which has good elasticity and good deformation continuity, meeting the usage requirements.

[0036] The intelligent adaptive fixture for dynamic modulus testing of multi-size specimens provided in this embodiment, compared with the prior art, in the clamping process, the central control unit 7 first controls the holding component 2 to move downward along the vertical support component 3; when the detection value of at least one pressure sensor 6 reaches the preset contact threshold, it is determined that the floating contact plate 22 has contacted the surface of the specimen.

[0037] Subsequently, the central control unit 7 continues to collect multi-point pressure data from multiple pressure sensors 6, and controls the main pressure plate 21 to make compensatory position adjustments based on the differences in readings between each detection point. This causes the elastic support 23 between the main pressure plate 21 and the floating contact plate 22 to produce differential compression, thereby causing the floating contact plate 22 to adaptively tilt or slightly displace relative to the main pressure plate 21 until the pressure difference between each detection point is reduced to within the preset uniformity threshold, thus completing the adaptive clamping of the specimen.

[0038] The main pressure plate 21, floating contact plate 22 and elastic support 23 form a pressure holding structure with floating compensation capability, so that the pressure holding assembly 2 can adaptively adjust to the uneven surface, dimensional deviation or slight placement of the specimen after contacting the specimen. It can adapt to AMPT specimens of different heights and even different sizes, and improve the versatility and adaptability of the fixture.

[0039] It can compensate for local premature contact, local suspension and stress concentration caused by uneven end face of the specimen, so that the specimen is subjected to more uniform force; it can reduce the test error caused by clamping misalignment and inconsistent force, and improve the stability and centering of the specimen clamping.

[0040] The position and force states during the clamping process are detected in real time by displacement sensor 5 and multiple pressure sensors 6. The central control unit 7 performs closed-loop adjustment based on the detection results, thereby transforming the clamping process from the traditional mechanical passive clamping to a perceptible, judgmental, and adjustable active pressure equalization clamping process. This improves the consistency and repeatability of the clamping process and reduces the influence of human experience on clamping quality. As a result, the accuracy, reliability, and repeatability of the dynamic modulus test results are improved, and the automation level and operational efficiency of the testing process are enhanced.

[0041] In some embodiments, see Figure 1 and Figure 2 The vertical support assembly 3 includes multiple support rods 31 and multiple sliding rings 32. The multiple support rods 31 are distributed at intervals along the circumference of the base 1; the bottom end of the support rod 31 is connected to the base 1, and the top end of the support rod 31 slides through the floating contact plate 22 and the main pressure plate 21; the multiple sliding rings 32 are slidably sleeved on the outer periphery of the corresponding support rod 31 and are located between the floating contact plate 22 and the base 1, and each sliding ring 32 is connected to the main pressure plate 21.

[0042] In this embodiment, multiple support rods 31 spaced apart along the circumference and sliding rings 32 together form a multi-point guiding support structure for the main pressure plate 21, which can provide stable vertical motion constraints during the lifting and lowering of the pressure holding assembly 2, and reduce the swaying, swinging or jamming problems caused by single-point support.

[0043] Multiple support rods 31 are distributed around the base 1, which helps to maintain the overall balance and coaxiality of the main pressure plate 21 relative to the base 1, so that the pressing assembly 2 can still maintain high motion accuracy when adapting to specimens of different sizes.

[0044] After the sliding ring 32 is connected to the main pressure plate 21, the load of the main pressure plate 21 can be distributed to each support rod 31, reducing the risk of structural deformation caused by excessive local stress, thereby improving the stability and repeatability of the clamping process, and providing a reliable mechanical basis for subsequent pressure equalization adjustment and dynamic modulus testing.

[0045] In some embodiments, see Figure 1 and Figure 6 An L-shaped connecting plate 33 connects the sliding ring 32 and the main pressure plate 21. The short arm of the L-shaped connecting plate 33 is connected to the sliding ring 32, and the top of the long arm is connected to the upper surface of the main pressure plate 21, so that the sliding ring 32 and the main pressure plate 21 can be raised and lowered synchronously.

[0046] Specifically, multiple sliding rings 32 are interconnected to achieve synchronous lifting and lowering of each sliding ring 32.

[0047] Specifically, the sliding hole diameters of the floating contact plate 22 and the main pressure plate 21 corresponding to the support rod 31 are both larger than the outer diameter of the support rod 31, so as to prevent the floating contact plate 22 from being unable to tilt or move slightly relative to the main pressure plate 21.

[0048] In some embodiments, see Figure 6 The sliding ring 32 is connected to a driving component 34, which is used to drive the sliding ring 32 to move up and down along the corresponding support rod 31 axially.

[0049] Specifically, the drive unit 34 is electrically connected to the central control unit 7.

[0050] In this embodiment, the sliding ring 32 is actively driven by the driving component 34, which realizes rapid lifting and precise position control of the holding component 2, significantly reducing the clamping operation intensity and improving the adjustment efficiency.

[0051] After the driving component 34 acts on each sliding ring 32, it can achieve synchronous lifting or differentiated adjustment according to control requirements, thereby better cooperating with the compensating displacement action of the main pressure plate 21 and improving the adaptability to specimens of different heights and uneven end faces.

[0052] The inclusion of drive component 34 also facilitates the central control unit 7 in programmatically controlling the clamping process, making the clamping action more continuous and controllable, reducing human error, and thus improving the consistency of specimen clamping, the degree of automation, and the efficiency of preparation before dynamic modulus testing. Specifically, the drive component 34 is connected to the corresponding sliding ring 32 through a lead screw lifting structure.

[0053] Specifically, the driving component 34 can also be any one of an electric cylinder, a stepper motor drive mechanism, a servo motor drive mechanism, or a pneumatic cylinder drive mechanism.

[0054] Specifically, see Figure 7 The lifting end of the drive component 34 can also be connected to the L-shaped connecting plate 33, and indirectly connected to the sliding ring 32 through the L-shaped connecting plate 33.

[0055] During use, the drive component 34 is connected to the sliding ring 32 or the L-shaped connecting plate 33 for transmission.

[0056] In some embodiments, see Figure 2 The sliding ring 32 is provided with an electromagnetic locking structure 4. The electromagnetic locking structure 4 has a locking part that cooperates with the support rod 31. After the pressing component 2 reaches the preset position, the locking part abuts against the support rod 31 to restrict the sliding ring 32 from moving up and down along the support rod 31.

[0057] In this embodiment, by setting an electromagnetic locking structure 4 at the sliding ring 32, the clamping component 2 can be locked in time after reaching the target position, preventing relative displacement caused by vibration, repeated loading or structural springback during the test, thereby improving the overall rigidity of the fixture and the stability of the clamping state.

[0058] After the locking part abuts against the support rod 31, it can reliably maintain the completed height adjustment result, avoiding the uncertainty of manual secondary tightening. It can also be linked with the control system to achieve automatic locking and unlocking, improving operational convenience. This helps ensure that the specimen maintains stable force boundary conditions throughout the dynamic modulus test, reduces the interference of fixture displacement drift on the test results, and improves the reliability and repeatability of the test data.

[0059] In some embodiments, see Figure 3 and Figure 4 The elastic support member 23 includes a plurality of elastic members 231, which are arranged in a circumferential array along the main pressure plate 21. The elastic members 231 have a preload force that pushes the floating contact plate 22 away from the main pressure plate 21.

[0060] Specifically, multiple pressure sensors 6 are respectively installed on the top of the corresponding elastic element 231, and the top of the pressure sensor 6 is connected to the main pressure plate 21.

[0061] Specifically, multiple elastic elements 231 in the same ring are arranged in a circumferential array along the main pressure plate 21, while elastic elements 231 in different rings are arranged radially along the main pressure plate 21.

[0062] In this embodiment, multiple elastic elements 231 distributed circumferentially along the main pressure plate 21 provide pre-tightening support for the floating contact plate 22, which enables the floating contact plate 22 to maintain an initial stable position when it is not in contact with the test piece, and to generate differentiated compression according to the force conditions of different areas after contact, thereby achieving sensitive attitude compensation.

[0063] The circumferentially distributed elastic element 231 helps to provide a more balanced elastic response in all directions, enabling the floating contact plate 22 to more effectively adapt to uneven end faces, local height differences, or slight tilting of the specimen, thereby improving the fit of the contact surface.

[0064] The preload setting can also reduce the free travel and free sway of the floating contact plate 22, improve the timeliness of contact recognition and the smoothness of the adjustment process, thereby enhancing the clamping stability and force uniformity.

[0065] In some embodiments, see Figure 3 The pressure holding assembly 2 also includes a connecting sleeve 24, which is fitted around the outer periphery of the main pressure plate 21 and the floating contact plate 22. The connecting sleeve 24, the main pressure plate 21 and the floating contact plate 22 enclose the installation space of the elastic support member 23.

[0066] Specifically, the outer diameter of the floating contact plate 22 is smaller than the inner diameter of the connecting sleeve 24, so that the floating contact plate 22 can be stably adjusted up and down.

[0067] In this embodiment, the main pressure plate 21 and the floating contact plate 22 are connected by a connecting sleeve 24, which encloses and forms an installation space for the elastic support 23. This provides a relatively closed and stable arrangement environment for the elastic support 23, avoiding displacement, detachment or contamination caused by the exposure of the elastic support 231.

[0068] The connecting sleeve 24 helps to constrain the relative movement range between the main pressure plate 21 and the floating contact plate 22, so that the floating compensation action is carried out within a controllable path. On the other hand, it also facilitates the overall assembly, disassembly and maintenance of the pressure holding assembly 2, and improves the structural integration.

[0069] The connecting sleeve 24 can also provide some protection for the internal elastic support area, reducing the impact of dust, particulate matter or test environment factors on the working state of the elastic element 231, thereby improving the reliability of the fixture for long-term use and the stability of compensation adjustment.

[0070] In some embodiments, see Figure 2 The bottom surface of the floating contact plate 22 and the top surface of the base 1 are respectively provided with wear-resistant layers 8. By providing wear-resistant layers 8 on the bottom surface of the floating contact plate 22 and the top surface of the base 1, the wear on the contact surface during repeated loading, unloading and loading of the specimen can be effectively reduced, and the problems of surface scratches, local dents or roughness changes caused by long-term use can be mitigated.

[0071] Optionally, the wear-resistant layer 8 may be made of polytetrafluoroethylene, ultra-high molecular weight polyethylene, wear-resistant rubber, polyurethane, nylon composite layer, ceramic sheet layer, hard alloy layer, metal spray coating, surface hardening layer or other wear-resistant materials suitable for repeated contact conditions.

[0072] The wear-resistant layer 8 maintains the dimensional accuracy and frictional characteristics of the upper and lower contact surfaces, preventing specimen stress deviation or positioning instability caused by inconsistent wear on the contact surfaces. The wear-resistant layer 8 also reduces damage to the fixture body from hard contact to a certain extent, extending the service life of key components and reducing maintenance and replacement frequency. This helps the fixture maintain relatively stable clamping performance and test boundary conditions during long-term batch testing, improving the consistency of test results.

[0073] In some embodiments, see Figure 5 The displacement sensor 5 includes a detection element and a reading part. The detection element extends along the axial direction of the support rod 31, and the reading part is connected to the main pressure plate 21 to detect the relative position of the main pressure plate 21 relative to the base 1.

[0074] In this embodiment, the detection element of the displacement sensor 5 is arranged on the support rod 31, allowing it to directly detect the positional change of the main pressure plate 21 relative to the base 1. This more accurately reflects the lifting and lowering state of the actual pressing contact part, which helps improve the position monitoring accuracy during the clamping process. The detection element extends axially along the support rod 31, facilitating its integration with the overall guide structure and reducing the impact of installation deviations on the measurement results.

[0075] Specifically, see Figure 5 The reading section of the displacement sensor 5 is installed in the gap between the main pressure plate 21 and the support rod 31.

[0076] Specifically, the reading section of the displacement sensor 5 can also be installed at the bottom of the main pressure plate 21.

[0077] Specifically, the displacement sensor 5 can be equipped with two detection elements. One detection element is installed at the bottom of the main pressure plate 21, and the other detection element is installed at the bottom of the floating contact plate 22. The displacement of the main pressure plate 21 and the displacement of the floating contact plate 22 are obtained respectively, thereby obtaining the actual height of the main pressure plate 21 and the floating contact plate 22.

[0078] By acquiring real-time displacement information of the main pressure plate 21 and the floating contact plate 22, the central control unit 7 can more effectively determine the contact time, compensation stroke and holding state, avoiding judgment distortion caused by structural gaps or elastic deformation, thereby improving the accuracy, stability and traceability of the clamping control and the testing process.

[0079] In some embodiments, see Figure 2The intelligent adaptive fixture for dynamic modulus testing of multi-size specimens in AMPT also includes a laser guide 9, which is mounted on the base 1 and oriented toward the specimen placement area. The laser guide 9 is used to indicate the installation position of the specimen relative to the base 1.

[0080] By setting up a laser guide 9 facing the specimen placement area, an intuitive positioning reference can be provided before the specimen is clamped, helping operators to quickly place specimens of different sizes in the predetermined center area and reduce positional deviations caused by manual visual alignment.

[0081] For batch testing or replacement of specimens of different specifications, this structure can shorten the specimen alignment time, improve the sample loading efficiency, and reduce the risk of increased difficulty in subsequent compensation and adjustment due to excessive initial placement eccentricity.

[0082] Laser guidance is characterized by clear indication, non-contact operation, and easy observation. It can be combined with intelligent control systems to form a more standardized clamping process, improving the initial installation consistency of specimens from the source, and further enhancing clamping accuracy and the stability of dynamic modulus test results.

[0083] In some embodiments, see Figure 2 The central control unit 7 is equipped with a communication interface 71 and a display unit 72. The communication interface 71 is used to connect with the dynamic modulus testing system, and the display unit 72 is used to display the displacement value detected by the displacement sensor 5 and the multi-point pressure value detected by the pressure sensor 6.

[0084] In this embodiment, the display unit 72 can display the displacement position and multi-point pressure values ​​in real time, allowing operators to intuitively grasp the contact state of the specimen, the uniformity of force, and the adjustment results, facilitating timely judgment on whether the clamping requirements have been met. This structure not only helps reduce blind operation and reliance on experience, but also enhances the visualization, recordability, and traceability of the testing process, thereby improving the intelligence level of the equipment and the efficiency of experimental management, and providing a basis for subsequent data analysis and anomaly troubleshooting.

[0085] It should be noted that communication interface 71 refers to the interface for data exchange between the central control unit 7 and the dynamic modulus testing system, host computer, external control terminal, or data acquisition platform. Communication interface 71 can be an RS232 interface, RS485 interface, CAN bus interface, Ethernet interface, USB interface, serial communication interface 71, wireless communication module interface, Bluetooth communication interface, WiFi communication interface, or industrial fieldbus interface.

[0086] Through the communication interface 71, the central control unit 7 can send displacement data detected by the displacement sensor 5, multi-point pressure data detected by the pressure sensor 6, locking status, clamping completion signal, fault alarm information, etc., to the dynamic modulus testing system or the host computer. At the same time, it can also receive control commands from external systems such as start, stop, reset, parameter setting, threshold adjustment, and mode switching.

[0087] The above description is merely a preferred embodiment of this application and is not intended to limit this application. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. An intelligent adaptive fixture for dynamic modulus testing of multi-size AMPT specimens, characterized in that, include: Base; A vertical support assembly is mounted on the base; The pressing assembly is vertically mounted on the vertical support assembly and located above the base. The pressing assembly includes a main pressing plate, a floating contact plate located below the main pressing plate, and an elastic support member disposed between the main pressing plate and the floating contact plate. The sensing assembly includes a displacement sensor and multiple pressure sensors. The displacement sensor detects the displacement position of the main pressure plate, and the multiple pressure sensors are evenly distributed between the main pressure plate and the elastic support member to detect multi-point pressure values ​​between them. The central control unit is communicatively connected to both the displacement sensor and the pressure sensor. The central control unit is configured as follows: Control the descent of the holding assembly; When the reading of at least one of the pressure sensors reaches a preset contact threshold, it is determined that the floating contact plate has contacted the specimen; After contact is determined, the main pressure plate is controlled to descend based on the difference in readings of all the pressure sensors. Through the differential compression of the elastic support, the floating contact plate adaptively tilts or shifts until the difference in readings is less than a preset uniformity threshold.

2. The intelligent adaptive fixture for dynamic modulus testing of multi-size AMPT specimens as described in claim 1, characterized in that, The vertical support component includes: Multiple support rods are spaced apart circumferentially along the base; the bottom end of each support rod is connected to the base, and the top end of each support rod slides through the floating contact plate and the main pressure plate; and Multiple sliding rings are slidably sleeved on the outer periphery of the corresponding support rods and located between the floating contact plate and the base. Each sliding ring is connected to the main pressure plate.

3. The intelligent adaptive fixture for dynamic modulus testing of multi-size AMPT specimens as described in claim 2, characterized in that, The sliding ring is connected to a driving component, which drives the sliding ring to move up and down along the axial direction of the corresponding support rod.

4. The intelligent adaptive fixture for dynamic modulus testing of multi-size AMPT specimens as described in claim 2, characterized in that, The sliding ring is provided with an electromagnetic locking structure, which has a locking part that cooperates with the support rod. After the pressing component reaches the preset position, the locking part abuts against the support rod to restrict the sliding ring from moving up and down along the support rod.

5. The intelligent adaptive fixture for dynamic modulus testing of multi-size AMPT specimens as described in claim 1, characterized in that, The elastic support includes multiple elastic elements, which are arranged in a circumferential array along the main pressure plate. Each elastic element has a preload force that pushes the floating contact plate away from the main pressure plate.

6. The intelligent adaptive fixture for dynamic modulus testing of multi-size AMPT specimens as described in claim 1, characterized in that, The pressing component further includes: A connecting sleeve is fitted around the outer periphery of both the main pressure plate and the floating contact plate. The connecting sleeve, the main pressure plate, and the floating contact plate together form the installation space for the elastic support member.

7. The intelligent adaptive fixture for dynamic modulus testing of multi-size AMPT specimens as described in claim 1, characterized in that, The bottom surface of the floating contact plate and the top surface of the base are respectively provided with wear-resistant layers.

8. The intelligent adaptive fixture for dynamic modulus testing of multi-size AMPT specimens as described in claim 2, characterized in that, The displacement sensor includes a detection element and a reading part. The detection element extends along the axial direction of the support rod, and the reading part is connected to the main pressure plate to detect the relative position of the main pressure plate with respect to the base.

9. The intelligent adaptive fixture for dynamic modulus testing of multi-size AMPT specimens as described in claim 1, characterized in that, The intelligent adaptive fixture for dynamic modulus testing of multi-size specimens in AMPT also includes a laser guide, which is disposed on the base and oriented toward the specimen placement area. The laser guide is used to indicate the installation position of the specimen relative to the base.

10. The intelligent adaptive fixture for dynamic modulus testing of multi-size AMPT specimens as described in claim 1, characterized in that, The central control unit is equipped with a communication interface and a display unit. The communication interface is used to connect with the dynamic modulus testing system, and the display unit is used to display the displacement value detected by the displacement sensor and the multi-point pressure value detected by the pressure sensor.

Images