Vibration measuring device and measuring method thereof

Abstract

The invention discloses a vibration measurement device and a measurement method thereof, and aims to solve the problem that the measurement precision of the conventional vibration measurement device is difficult to guarantee. The vibration measuring device comprises an eddy current sensor, a movable plate and a host, the eddy current sensor is arranged on the upper portion of the rack through a fixing frame, the movable plate is arranged on the upper surface of the loading system through a support, a metal block is arranged on the side of the movable plate, and the face, close to the eddy current sensor, of the metal block is inclined. The inclined surface is parallel to the probe end surface of the eddy current sensor; knobs are arranged on the outer wall of the bracket; the end face of the probe of the eddy current sensor and the inclined plane of the metal block are arranged in an inclined and parallel mode, the inclined plane triangulation measurement principle is adopted, a small-range sensor is converted into large-range measurement, accurate measurement of the vibration frequency and the vibration amplitude of the vibration compaction forming machine is achieved, and the overall measurement accuracy of the system is ensured.

Description

Technical Field

[0001] This application relates to the field of testing technology in road engineering, specifically to a vibration measuring device and its measuring method. Background Technology

[0002] Inorganic binder stabilized materials (such as cement and lime) are key materials for modern road base and subbase layers. Their engineering performance, especially strength, stability, and resistance to deformation, is directly related to the density achieved after compaction during construction. Currently, vibratory compaction molding machines are used to determine the optimal moisture content and maximum dry density of these materials under vibratory compaction conditions.

[0003] Patent document CN105403688A discloses a method and equipment for designing the mix proportion of cement-stabilized crushed stone base courses. This method and equipment can simulate the one-time compaction of cement-stabilized crushed stone base courses by a large-tonnage vibratory roller in the laboratory, achieving the optimal mix proportion for the cement-stabilized crushed stone base course and making the road more durable. However, this patent document cannot accurately correct the two key process parameters of the vibratory compaction unit: vibration frequency and amplitude, making it impossible to guarantee measurement accuracy and long-term reliability.

[0004] To overcome the aforementioned measurement accuracy issues, some improved solutions employ a vibration measurement device. This device typically consists of a signal transmitter 3 (an inductive eddy current sensor), a signal reflector 2 (such as a right-angled triangular prism metal block), a signal transmitter mounting bracket, and a main unit 5. Its installation method is as follows: Figure 1 As shown: Signal reflector 2 is fixed to the surface of the synchronous vibration motor or the lowering system 1 of the vibratory compaction molding machine, with the inclined surface of the signal reflector aligned with the support frame 4 of the vibratory compaction molding machine, and the distance between the signal reflector 2 and the support frame 4 is approximately 5 cm; signal transmitter 3 is installed on the signal transmitter mounting bracket, and the bracket is adjusted up and down so that the signal transmitter is aligned with the lower third of the signal reflector. However, this scheme also fails to accurately calibrate the vibration frequency and amplitude of the vibratory compaction unit, making it impossible to perform quick and easy calibration at the equipment usage site; at the same time, because the end face of the eddy current sensor is at a certain angle to the inclined surface, the distance between the eddy current sensor and the measured surface changes significantly during movement, resulting in a significant loss of measurement accuracy. On the other hand, it may also cause the sensor to exceed its measurement range. Summary of the Invention

[0005] Therefore, this application provides a vibration measuring device and its measuring method to solve the problem that existing vibration measuring devices cannot guarantee their measurement accuracy.

[0006] To achieve the above objectives, this application provides the following technical solution:

[0007] In a first aspect, a vibration measuring device is mounted on a compaction instrument, the compaction instrument comprising: a frame and an upper loading system mounted on the frame;

[0008] The vibration measurement device includes an eddy current sensor, a movable plate, and a main unit. The eddy current sensor is mounted on the upper part of the frame via a fixed bracket, and the probe end face of the eddy current sensor is inclined. The movable plate is mounted on the upper surface of the upper vehicle system via a bracket. A metal block is provided on the side of the movable plate near the eddy current sensor, and the side of the metal block near the eddy current sensor is inclined, and the inclined surface is parallel to the probe end face of the eddy current sensor. A knob is also provided on the outer wall of the bracket, and the knob is connected to the movable plate via a transmission mechanism for driving the movable plate and the metal block to move up and down.

[0009] The host is connected to the eddy current sensor, and the host is equipped with function keys for controlling the measurement process. The function keys include at least a start measurement key and a calibration setting key.

[0010] Optionally, the host's operation interface includes a main interface, a start measurement interface, and a calibration interface, wherein the main interface is provided with a start measurement button and a calibration setting button;

[0011] Both the start measurement interface and the calibration interface are equipped with a return control to return to the main interface from their respective interfaces, and the calibration interface is also equipped with a confirmation control.

[0012] Optionally, the operation interface also includes a parameter setting instruction interface, which displays system parameter setting specifications and operation guidance information.

[0013] Optionally, the transmission structure includes a lead screw, a gear, and a rack. One end of the lead screw is fixedly connected to the knob, the gear is fixedly sleeved on the outer wall of the middle part of the lead screw, the rack meshes with the gear, and the side of the rack is fixedly connected to one side of the movable plate.

[0014] Optionally, the bracket is fixed to the upper surface of the vehicle loading system by a suction cup;

[0015] The metal block is a prismatic metal block.

[0016] Optionally, the host computer includes a controller and an analog-to-digital converter, and the eddy current sensor is connected to the controller via the analog-to-digital converter;

[0017] The controller uses an STM32 chip, and the analog-to-digital converter uses an AD7606 chip. The AD7606 chip and the STM32 chip are connected via a parallel bus.

[0018] Optionally, the compaction instrument is a vibratory compaction molding machine, which includes a frame and a loading system;

[0019] The bottom of the frame is provided with a steel mold for holding the material to be compacted; the upper carriage system is installed on the upper part of the frame through a lifting mechanism, and the lower carriage system is installed below the upper carriage system. The bottom of the lower carriage system is provided with a vibrating pressure head for pressing on the surface of the material to be compacted. An eccentric wheel mechanism is installed on the upper part of the lower carriage system, and the eccentric wheel mechanism is connected to the motor through a transmission shaft.

[0020] Secondly, a measurement method using a vibration measuring device, comprising the above-mentioned vibration measuring device, includes the following steps:

[0021] S1. Device installation and mode preparation: Install the vibration measuring device on the upper surface of the vehicle system, and make the tilt probe end face of the eddy current sensor parallel to the inclined surface of the metal block.

[0022] Click the "Start Measurement" button on the main interface of the host to enter the start measurement interface;

[0023] S2. Calibration Data Acquisition: Under the start measurement interface, operate the calibration unit of the vibration measurement device according to the guidance of the calibration diagram;

[0024] By manually adjusting the knob, the movable plate and the metal block are driven to move vertically to the first positioning point, and the first voltage value Umin and the corresponding first distance value Dmin output by the eddy current sensor at this time are recorded.

[0025] Subsequently, by adjusting the knob again, the movable plate and the metal block are driven to move vertically to the second positioning, and the second voltage value Umax and the corresponding second distance value Dmax output by the eddy current sensor are recorded at this time.

[0026] S3. Input and confirm calibration parameters: Return to the main interface from the start measurement interface and enter the calibration interface;

[0027] In the calibration interface, the first voltage value Umin, the second voltage value Umax, the height value H, the amplitude correction coefficient K1 and the frequency correction coefficient K2 are respectively input into the corresponding parameter fields. The height value H is the vertical distance between the first calibration position and the second calibration position.

[0028] Then, click the OK button. The host calculates and establishes the voltage-displacement conversion relationship based on Umin, Umax and H, and stores the voltage-displacement conversion relationship, amplitude correction coefficient K1 and frequency correction coefficient K2 to complete the system calibration configuration.

[0029] S4. Vibration Measurement and Result Display: Return from the calibration interface and re-enter the start measurement interface;

[0030] Start the vibratory compaction molding machine, so that the vibratory head at the bottom of the unloading system descends to the surface of the material to be compacted inside the steel mold and generates working vibration;

[0031] The voltage signal collected by the eddy current sensor is sent to the host in real time. Based on the voltage-displacement conversion relationship, the host converts the voltage signal into a vibration displacement signal, processes and analyzes the vibration displacement signal, and calculates the original vibration amplitude value and the original vibration frequency value.

[0032] Based on the amplitude correction coefficient K1 and the frequency correction coefficient K2, the host computer corrects the original vibration amplitude value and the original vibration frequency value to obtain and display the final vibration amplitude and vibration frequency.

[0033] Optionally, in step S1, a reference gauge block is placed between the probe end face and the inclined plane to ensure that the two are parallel and opposite.

[0034] In step S2, the first positioning and the second positioning are the lower limit and upper limit of the vertical movement range that can be achieved by driving the movable plate and the metal block through the knob, respectively.

[0035] Optionally, the first voltage value Umin is 2V, and the corresponding first distance value Dmin is 1mm; the second voltage value Umax is 7V-9.9V, and the corresponding second distance value Dmax is 3.5mm-5mm;

[0036] The default values ​​for both the amplitude correction coefficient K1 and the frequency correction coefficient K2 are 1.000.

[0037] Compared with the prior art, this application has at least the following beneficial effects:

[0038] 1. Based on further analysis and research of existing technical problems, this application provides a vibration measurement device that can be installed on a vibration compaction molding machine. The vibration measurement device includes an eddy current sensor, a movable plate, and a main unit. The eddy current sensor is mounted on the upper part of the frame via a fixed bracket. The movable plate is mounted on the upper surface of the upper system via a bracket. A metal block is provided on the side of the movable plate near the eddy current sensor, and the side of the metal block near the eddy current sensor is inclined, with the inclined surface parallel to the probe end face of the eddy current sensor. A knob is also provided on the outer wall of the bracket for driving the movable plate and the metal block on its side to move up and down. The main unit and the main unit are connected to the... The eddy current sensor is connected, and the host is equipped with function keys for controlling the measurement process. The overall structure of this application is reasonable, compact, reliable, and the calibration process is simple and efficient. By setting the probe end face of the eddy current sensor to be inclined and parallel to the inclined plane of the metal block, the inclined plane triangulation measurement principle is adopted to linearly convert the small change of the normal distance between the eddy current sensor and the inclined plane into a large vertical displacement measurement. This transforms the small-range sensor into a large-range measurement, realizing the accurate measurement of the vibration frequency and vibration amplitude of the vibratory compaction molding machine. The measurement error of frequency and amplitude is small, and the overall measurement accuracy of the system is ensured.

[0039] 2. The host of this application includes a controller and an analog-to-digital converter. The analog-to-digital converter uses an AD7606 chip, and the controller uses an STM32 chip. The AD7606 chip and the STM32 chip are connected via a parallel bus. The parallel port acquisition scheme using STM32 and AD7606 chips improves the acquisition speed, enabling it to reach 100kHz, significantly reducing signal distortion and achieving effective restoration of vibration amplitude. The upper limit of the response frequency of the eddy current sensor is 25kHz, and a 4x sampling rate enables accurate signal acquisition.

[0040] 3. This application also provides a measurement method for a vibration measuring device. Through the combined use of knobs and operating interfaces, users can directly complete the system calibration configuration on the vibration compaction molding machine, which greatly improves the convenience of calibration and further ensures the long-term reliability and accuracy of measurement results. Attached Figure Description

[0041] To more intuitively illustrate the prior art and this application, exemplary drawings are provided below. It should be understood that the specific shapes and structures shown in the drawings should not generally be regarded as limiting conditions for implementing this application; for example, based on the technical concept disclosed in this application and the exemplary drawings, those skilled in the art are able to easily make conventional adjustments or further optimizations to the addition / reduction / classification, specific shapes, positional relationships, connection methods, size ratios, etc. of certain units (components).

[0042] Figure 1A vibration measuring device and its installation diagram provided in the prior art of this application;

[0043] Explanation of reference numerals in the attached figures:

[0044] 1. Disembarkation system; 2. Signal reflector; 3. Signal transmitter; 4. Support frame; 5. Main unit;

[0045] Figure 2 This is a schematic diagram of a vibration compaction molding machine provided in one embodiment of this application;

[0046] Figure 3 This is a schematic diagram of a vibration measuring device installed in a vibration compaction molding machine according to one embodiment of this application;

[0047] Figure 4 for Figure 3 Schematic diagram of the vibration measuring device;

[0048] Figure 5 for Figure 4 The calibration diagram shown;

[0049] Figure 6 for Figure 3 A schematic diagram of the main interface of the vibration measuring device during operation;

[0050] Figure 7 for Figure 3 A schematic diagram of the starting measurement interface when the vibration measuring device is in operation;

[0051] Figure 8 for Figure 3 A schematic diagram illustrating the parameter settings interface of a vibration measurement device during operation.

[0052] Figure 9 for Figure 3 A schematic diagram of the calibration interface of the vibration measuring device during operation;

[0053] Figure 10 This is a circuit block diagram of a vibration measuring device provided in one embodiment of this application.

[0054] Explanation of reference numerals in the attached figures:

[0055] 1. Steel mold base; 2. Steel mold; 3. Steel mold collar; 4. Vibration head; 5. Unloading system; 6. Shock absorber block; 7. Eccentric wheel mechanism; 8. Loading system; 9. Guide column; 10. Frame; 11. Drive shaft; 12. Motor; 13. Frequency converter; 14. Suction cup; 15. Knob; 16. Movable plate; 17. Eddy current sensor; 18. Metal block; 19. Bracket; 20. Fixing frame; 21. Main unit; 22. Start measurement button; 23. Calibration setting button; 24. Operation interface. Detailed Implementation

[0056] The present application will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0057] In the description of this application: unless otherwise stated, "a plurality of" means two or more. The terms "first," "second," "third," etc., in this application are intended to distinguish the objects referred to and do not have any special meaning in terms of technical connotation (e.g., they should not be construed as an emphasis on importance or order). Expressions such as "including," "comprising," and "having" also mean "not limited to" (certain units, components, materials, steps, etc.).

[0058] The terms used in this application, such as "upper," "lower," "left," "right," and "middle," are generally used to indicate the general relative positional relationship for the purpose of intuitive understanding by referring to the accompanying drawings, and are not absolute limitations on the positional relationship in the actual product.

[0059] One embodiment of this application, such as Figures 2-10 As shown, a vibration measuring device is installed on a compaction instrument, which is a vibratory compaction molding machine or a compaction device, etc. This application takes a vibratory compaction molding machine as an example. The vibratory compaction molding machine includes: a frame 10, an upper system 8, and a lower system 5. A steel mold 2 for holding the material to be compacted is provided at the bottom of the frame 10. The material to be compacted is cement, lime, or lime-fly ash stabilized medium- and coarse-grained material. The upper system 8 is installed on the upper part of the frame 10 via a lifting mechanism. The lower system 5 is installed below the upper system 8, and a vibratory pressure head 4 for pressing against the surface of the material to be compacted is provided at the bottom of the lower system 5. An eccentric wheel mechanism 7 is installed on the upper part of the lower system 5, and the eccentric wheel mechanism 7 is connected to a motor 12 via a transmission shaft 11. The lifting mechanism can be an electric hoist.

[0060] The vibration measurement device includes an eddy current sensor 17, a movable plate 16, and a main unit 21. The eddy current sensor 17 is used to sense displacement and output an electrical signal. The eddy current sensor 17 is mounted on the upper part of the frame 10 via a fixed bracket 20, and the probe end face of the eddy current sensor 17 is inclined. The movable plate 16 is mounted on the upper surface of the upper vehicle system 8 via a bracket 19. A metal block 18 is provided on the side of the movable plate 16 near the eddy current sensor 17. The side of the metal block 18 near the eddy current sensor 17 is inclined and parallel to the probe end face of the eddy current sensor 17. A knob 15 is also provided on the outer wall of the bracket 19. The knob 15 is connected to the movable plate 16 via a transmission mechanism and is used to drive the movable plate 16 and the metal block 18 on its side to move up and down.

[0061] The host 21 is connected to the eddy current sensor 17, and the host 21 is provided with function keys for controlling the measurement process. The function keys include at least the start measurement key 22 and the calibration setting key 23.

[0062] Preferably, the transmission structure includes a lead screw, a gear, and a rack. One end of the lead screw is fixedly connected to the knob 15. The gear is fixedly sleeved on the outer wall of the middle part of the lead screw. The rack meshes with the gear, and the side of the rack is fixedly connected to one side of the movable plate 16. During operation, the user manually rotates the knob 15 to drive the lead screw to rotate. The lead screw drives the gear on it to rotate synchronously. The gear drives the rack meshing with it to make a vertical linear motion, thereby driving the movable plate 16 fixed thereto and the metal block 18 on it to move up and down synchronously.

[0063] More preferably, the bracket 19 is fixed to the upper surface of the loading system 8 by a suction cup 14; the metal block 18 may be a triangular prism metal block.

[0064] Preferably, such as Figures 6-9 As shown, the operation interface 24 of the host 21 includes a main interface, a start measurement interface, and a calibration interface. The main interface is equipped with a start measurement button 22 and a calibration setting button 23. Both the start measurement interface and the calibration interface are equipped with a return control to return to the main interface from their respective interfaces, and the calibration interface is also equipped with a confirm control.

[0065] The main interface provides access to each core functional module; the start measurement interface displays measurement results in real time. Users access this interface through the main interface to start or stop vibration measurement and observe results such as voltage, amplitude, and frequency values ​​in real time; the calibration interface is used to input and configure the system's calibration parameters. Users access this interface through the main interface to input or modify calibration parameters, such as height H, first voltage value Umin, second voltage value Umax, amplitude correction coefficient K1, frequency correction coefficient K2, etc., where height H is the vertical distance between the first calibration point and the second calibration point, i.e., the distance from the first distance value Dmin to the second distance value Dmax.

[0066] More preferably, the operating interface 24 of the host 21 also includes a parameter setting explanation interface, such as... Figure 8 As shown, this parameter setting instruction interface is used to display system parameter setting specifications and operation guidance information, including calibration height range, correction coefficient definition and installation parallelism requirements. The parameter setting instruction interface can be accessed through the function entry of the main interface or calibration interface.

[0067] The parameter settings are explained in detail below:

[0068] 1. The height is the distance from Umin to Umax of the lifting platform. The lifting platform needs to be leveled during calibration.

[0069] 2. A Umin value of approximately 2V corresponds to a distance of approximately 1mm;

[0070] 3. Umax value from 7V to 9.9V corresponds to a distance of 3.5mm to 5mm;

[0071] 4. K1 is the amplitude correction factor, with a default value of 1.000;

[0072] 5. K2 is the frequency correction factor, with a default value of 1.000;

[0073] 6. When calibrating, the end face of the sensor is parallel to the rhomboid bevel and a 1mm gauge block can be used as a reference.

[0074] Preferably, the host 21 includes a controller and an analog-to-digital converter (ADC). The eddy current sensor 17 is connected to the controller via the ADC. The ADC uses an AD7606 chip and is responsible for converting the analog voltage signal output by the eddy current sensor 17 into a digital signal. The controller uses an STM32 chip and is responsible for system control and data processing.

[0075] The AD7606 chip and the STM32 chip are connected via a parallel bus. The parallel port acquisition scheme using the STM32 and AD7606 chips improves the acquisition speed, enabling it to reach 100KHz, significantly reducing signal distortion and achieving effective restoration of vibration amplitude. The upper limit of the response frequency of the eddy current sensor is 25KHz, and a 4x sampling rate enables accurate signal acquisition.

[0076] Preferably, such as Figure 2 As shown, the steel mold 2 is connected to the frame 10 through the steel mold base 1; a steel mold collar 3 is provided on the top of the steel mold 2 to ensure that the vibrating pressure head 4 can be accurately pressed into the steel mold 2.

[0077] The steel mold collar 3, the steel mold base 1, and the frame 10 are fixed together by bolts.

[0078] More preferably, guide columns 9 are vertically arranged on both sides of the upper part of the frame 10. The guide columns 9 are connected to both sides of the upper vehicle system 8 to guide the upper vehicle system 8, ensure the verticality of the compaction action, and prevent swaying.

[0079] Preferably, the alighting system 5 is connected to the loading system 8 via a connector; a shock-absorbing block 6 is also installed between the alighting system 5 and the loading system 8.

[0080] Preferably, the motor 12 is fixed to the ground by a motor bracket, and the motor 12 is also electrically connected to the frequency converter 13 (or electrical control box); the drive shaft 11 is driven to rotate by the motor 12, and the frequency converter 13 is used to control the operation of the motor 12, thereby controlling the vibration frequency, time and compaction pressure required by the vibrating head 4.

[0081] This application also provides a measurement method using a vibration measuring device, comprising the following steps:

[0082] S1. Device installation and mode preparation: Install the vibration measuring device on the upper surface of the upper system 8 of the vibration compaction molding machine, and make the inclined probe end face of the eddy current sensor 17 parallel and opposite to the inclined surface of the metal block 18 on the movable plate 16.

[0083] On the main interface of host 21 (see...) Figure 6 Click the "Start Measurement" button 22 to enter the start measurement interface (see...). Figure 7 );

[0084] S2. Calibration Data Acquisition: On the start measurement interface, refer to the calibration diagram (see...). Figure 5 Guided by the operation of the calibration unit of the vibration measurement device;

[0085] By manually adjusting knob 15, the movable plate 16, together with the metal block 18, is driven to move vertically to the first positioning point. Figure 5 (position 1) and record the first voltage value Umin and the corresponding first distance value Dmin output by the eddy current sensor 17 at this time;

[0086] Subsequently, by adjusting knob 15 again, the movable plate 16, together with the metal block 18, is driven to move vertically to the second positioning point. Figure 5 (position 2 in the middle), and record the second voltage value Umax and the corresponding second distance value Dmax output by the eddy current sensor 17 at this time;

[0087] S3. Calibration Parameter Input and Confirmation: Return to the main interface from the start measurement interface and enter the calibration interface (see...). Figure 8 );

[0088] In the calibration interface, the first voltage value Umin, the second voltage value Umax, the height value H, the amplitude correction coefficient K1 and the frequency correction coefficient K2 are entered into the corresponding parameter fields respectively. The height value H is the vertical distance between the first calibration position and the second calibration position.

[0089] Then, click the OK control. The host 21 calculates and establishes the voltage-displacement conversion relationship based on Umin, Umax and H, and stores the voltage-displacement conversion relationship as well as the amplitude correction coefficient K1 and the frequency correction coefficient K2, thereby completing the system calibration configuration.

[0090] S4. Vibration Measurement and Result Display: Return from the calibration interface and re-enter the start measurement interface;

[0091] Start the vibratory compaction molding machine, so that the vibratory head 4 at the bottom of the unloading system 5 descends to the surface of the material to be compacted inside the steel mold 2 and generates working vibration;

[0092] The voltage signal collected by the eddy current sensor 17 is sent to the host 21 in real time. The host 21 converts the voltage signal into a vibration displacement signal based on the voltage-displacement conversion relationship, and processes and analyzes the vibration displacement signal to calculate the original vibration amplitude value and the original vibration frequency value.

[0093] Based on the amplitude correction coefficient K1 and the frequency correction coefficient K2, the host 21 corrects the original vibration amplitude value and the original vibration frequency value to obtain and display the final vibration amplitude and vibration frequency.

[0094] In step S1, during calibration, a reference gauge block is placed between the probe end face and the inclined surface of the metal block 18 to ensure that the two are parallel and relative.

[0095] In step S2, the first positioning and the second positioning are the lower limit and upper limit of the vertical movement range that can be achieved by driving the movable plate 16 and the metal block 18 through the knob 15, respectively.

[0096] The first voltage value Umin is approximately 2V, and the corresponding first distance value Dmin is approximately 1mm.

[0097] The second voltage value Umax is 7V-9.9V, and the corresponding second distance value Dmax is 3.5mm-5mm;

[0098] The default values ​​for both amplitude correction factor K1 and frequency correction factor K2 are 1.000.

[0099] In summary, this application has at least the following advantages:

[0100] The vibration measurement device provided in this application is installed on the upper surface of the upper system of the vibratory compaction molding machine. It uses a high-precision eddy current sensor in conjunction with a metal block. The inclined surface of the metal block is tilted and parallel to the probe end face of the eddy current sensor, enabling precise measurement of the vibration frequency and amplitude of the vibratory compaction molding machine. Through the principle of inclined plane triangulation, the small-range sensor is converted into a large-range sensor. The measurement range of the eddy current sensor is 5mm, which is increased to 60mm through triangulation. Simultaneously, the overall measurement accuracy is not reduced, and the nonlinearity of the eddy current sensor is 2%.

[0101] The host 21 of this application includes a controller and an analog-to-digital converter. The analog-to-digital converter uses an AD7606 chip, and the controller uses an STM32 chip. The AD7606 chip and the STM32 chip are connected via a parallel bus. The parallel port acquisition scheme using STM32 and AD7606 chips improves the acquisition speed, enabling it to reach 100kHz, significantly reducing signal distortion and achieving effective restoration of vibration amplitude. The upper limit of the response frequency of the eddy current sensor is 25kHz, and a 4x sampling rate enables accurate signal acquisition.

[0102] The maximum frequency error was ultimately achieved to be 0.05Hz, and the maximum amplitude error to be 0.05mm.

[0103] The technical features of the above embodiments can be combined in any way (as long as there is no contradiction in the combination of these technical features). For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described; these embodiments not explicitly written should also be considered to be within the scope of this specification.

Claims

1. A vibration measuring device, characterized in that, The vibration measuring device is installed on the compaction instrument, which includes: a frame and an upper loading system installed on the frame; The vibration measurement device includes an eddy current sensor, a movable plate, and a main unit. The eddy current sensor is mounted on the upper part of the frame via a fixed bracket, and the probe end face of the eddy current sensor is inclined. The movable plate is mounted on the upper surface of the upper vehicle system via a bracket. A metal block is provided on the side of the movable plate near the eddy current sensor, and the side of the metal block near the eddy current sensor is inclined, and the inclined surface is parallel to the probe end face of the eddy current sensor. A knob is also provided on the outer wall of the bracket, and the knob is connected to the movable plate via a transmission mechanism for driving the movable plate and the metal block to move up and down. The host is connected to the eddy current sensor, and the host is equipped with function keys for controlling the measurement process. The function keys include at least a start measurement key and a calibration setting key.

2. The vibration measuring device according to claim 1, characterized in that, The host's operating interface includes a main interface, a start measurement interface, and a calibration interface. The main interface is equipped with a start measurement button and a calibration setting button. Both the start measurement interface and the calibration interface are equipped with a return control to return to the main interface from their respective interfaces, and the calibration interface is also equipped with a confirmation control.

3. The vibration measuring device according to claim 2, characterized in that, The user interface also includes a parameter setting instructions interface, which displays system parameter setting specifications and operation guidance information.

4. The vibration measuring device according to claim 1, characterized in that, The transmission structure includes a lead screw, a gear, and a rack. One end of the lead screw is fixedly connected to the knob. The gear is fixedly sleeved on the outer wall of the middle part of the lead screw. The rack meshes with the gear, and the side of the rack is fixedly connected to one side of the movable plate.

5. The vibration measuring device according to claim 1, characterized in that, The bracket is fixed to the upper surface of the vehicle mounting system by suction cups; The metal block is a prismatic metal block.

6. The vibration measuring device according to claim 1, characterized in that, The host includes a controller and an analog-to-digital converter, and the eddy current sensor is connected to the controller through the analog-to-digital converter; The controller uses an STM32 chip, and the analog-to-digital converter uses an AD7606 chip. The AD7606 chip and the STM32 chip are connected via a parallel bus.

7. The vibration measuring device according to claim 1, characterized in that, The compaction instrument is a vibratory compaction molding machine, which includes a frame and a loading system. The bottom of the frame is provided with a steel mold for holding the material to be compacted; the upper carriage system is installed on the upper part of the frame through a lifting mechanism, and the lower carriage system is installed below the upper carriage system. The bottom of the lower carriage system is provided with a vibrating pressure head for pressing on the surface of the material to be compacted. An eccentric wheel mechanism is installed on the upper part of the lower carriage system, and the eccentric wheel mechanism is connected to the motor through a transmission shaft.

8. A measurement method for a vibration measuring device, characterized in that, The vibration measuring device according to claim 7 includes the following steps: S1. Device installation and mode preparation: Install the vibration measuring device on the upper surface of the vehicle system, and make the tilt probe end face of the eddy current sensor parallel to the inclined surface of the metal block. Click the "Start Measurement" button on the main interface of the host to enter the start measurement interface; S2. Calibration Data Acquisition: Under the start measurement interface, operate the calibration unit of the vibration measurement device according to the guidance of the calibration diagram; By manually adjusting the knob, the movable plate and the metal block are driven to move vertically to the first positioning point, and the first voltage value Umin and the corresponding first distance value Dmin output by the eddy current sensor at this time are recorded. Subsequently, by adjusting the knob again, the movable plate and the metal block are driven to move vertically to the second positioning, and the second voltage value Umax and the corresponding second distance value Dmax output by the eddy current sensor are recorded at this time. S3. Input and confirm calibration parameters: Return to the main interface from the start measurement interface and enter the calibration interface; In the calibration interface, the first voltage value Umin, the second voltage value Umax, the height value H, the amplitude correction coefficient K1 and the frequency correction coefficient K2 are respectively input into the corresponding parameter fields. The height value H is the vertical distance between the first calibration position and the second calibration position. Then, click the OK button. The host calculates and establishes the voltage-displacement conversion relationship based on Umin, Umax and H, and stores the voltage-displacement conversion relationship, amplitude correction coefficient K1 and frequency correction coefficient K2 to complete the system calibration configuration. S4. Vibration Measurement and Result Display: Return from the calibration interface and re-enter the start measurement interface; Start the vibratory compaction molding machine, so that the vibratory pressure head at the bottom of the unloading system descends to the surface of the material to be compacted inside the steel mold and generates working vibration; The voltage signal collected by the eddy current sensor is sent to the host in real time. Based on the voltage-displacement conversion relationship, the host converts the voltage signal into a vibration displacement signal, processes and analyzes the vibration displacement signal, and calculates the original vibration amplitude value and the original vibration frequency value. Based on the amplitude correction coefficient K1 and the frequency correction coefficient K2, the host computer corrects the original vibration amplitude value and the original vibration frequency value to obtain and display the final vibration amplitude and vibration frequency.

9. The measurement method of the vibration measuring device according to claim 8, characterized in that, In step S1, a reference block is placed between the probe end face and the inclined plane to ensure that the two are parallel and opposite. In step S2, the first positioning and the second positioning are the lower limit and upper limit of the vertical movement range that can be achieved by driving the movable plate and the metal block through the knob, respectively.

10. The measurement method of the vibration measuring device according to claim 9, characterized in that, The first voltage value Umin is 2V, and the corresponding first distance value Dmin is 1mm; the second voltage value Umax is 7V-9.9V, and the corresponding second distance value Dmax is 3.5mm-5mm; The default values ​​for both the amplitude correction coefficient K1 and the frequency correction coefficient K2 are 1.000.

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