A vertical measurement system and method for axial magnetic field distribution of a vertical bore axis magnet

Abstract

The application relates to the technical field of magnetic field testing, and provides a vertical measurement system and method for axial magnetic field distribution of a vertical hole shaft magnet. The measurement system comprises a magnet support structure, a motion mechanism, a plumb line winding mechanism, a plumb line, a gravity hammer, a three-dimensional Hall probe, a target ball, a motion controller and a data acquisition unit. The application can form a plumb measurement reference by matching the plumb line with the gravity hammer, reduce positioning deviation caused by flexural deformation of a rigid long rod, control the plumb line winding mechanism to drive the probe to move, and realize the purpose of accurate measurement of a large range of axial magnetic field in a limited space. In addition, the application further provides a method applied to the vertical measurement system for axial magnetic field distribution of a vertical hole shaft magnet, axial magnetic field distribution curve collection can be completed, three-dimensional magnetic field space distribution can be obtained by adjusting the transverse position of the probe, and the method is suitable for multiple types of magnets with shafts arranged along the vertical direction.

Description

Technical Field

[0001] This application relates to the technical field of magnetic field testing, and in particular to a vertical measurement system and method for the axial magnetic field distribution of a vertical hole shaft magnet. Background Technology

[0002] In the research, development, installation, and acceptance of magnets, magnetic field distribution testing is a crucial inspection step. For magnets with their axes arranged horizontally, existing technologies offer various mature testing methods capable of measuring the axial magnetic field distribution of different types of magnets, and these testing systems are widely used in engineering fields. For magnets with their axes arranged vertically, magnetic field testing requires acquiring magnetic field data along the hole axis. Currently, the testing of this type of magnet largely follows the technical approach used for horizontal magnet testing.

[0003] Current methods for measuring the axial magnetic field of vertical bore magnets typically employ a rigid measuring rod carrying a Hall probe. During testing, a vertical motion mechanism moves the rigid measuring rod along the magnet's bore axis, sequentially positioning the Hall probe at each axial measurement point. Simultaneously, magnetic field strength information is collected at the corresponding locations, and the data is processed to obtain the magnet's axial magnetic field distribution. To cover the entire testing range, the rigid measuring rod needs to be of sufficient length, and the vertical motion mechanism must have a corresponding stroke.

[0004] This approach suffers from decreased measurement accuracy when dealing with measurements across long axial lengths. The long, rigid measuring rod is prone to bending deformation due to its own weight, machining straightness, and assembly deviations. This causes the Hall probe's actual position to deviate from the intended measurement position, and the probe's measurement posture to shift, ultimately affecting the accuracy of the magnetic field measurement results. Furthermore, the long-stroke motion mechanism increases the overall height of the equipment, requiring greater clearance in the testing area. Summary of the Invention

[0005] In view of this, this application aims to provide a vertical measurement system and method for the axial magnetic field distribution of a vertical hole shaft magnet, in order to solve the above-mentioned technical problems.

[0006] To achieve the above objectives, the technical solution of this application is implemented as follows: In a first aspect, this application proposes a vertical measurement system for the axial magnetic field distribution of a vertical hole shaft magnet, comprising: A magnet support structure for mounting a magnet to be tested, wherein the axis of the hole in the magnet to be tested is arranged in the vertical direction; The motion mechanism is located above the magnet support structure; A plumb line take-up mechanism is mounted on the motion mechanism and can adjust its spatial position with the motion mechanism. A plumb line, one end of which is wound and connected to the plumb line take-up mechanism, and the other end extends downward in a vertical direction; A gravity hammer, connected to the lower end of the plumb line, is used to keep the plumb line taut and form a plumb line measurement reference. A three-dimensional Hall probe is positioned at the lower end of the plumb line and moves vertically as the plumb line expands and contracts. A target ball, mounted on the gravity hammer, is used to calibrate the spatial position of the sensitive area of ​​the three-dimensional Hall probe. A motion controller is electrically connected to the motion mechanism and the plumb line take-up mechanism, respectively, and is used to control the take-up and release actions of the plumb line and the position adjustment of the motion mechanism. The data acquisition unit is electrically connected to the three-dimensional Hall probe and is used to synchronously acquire probe position data and magnetic field strength data to obtain the axial magnetic field distribution of the magnet.

[0007] Furthermore, the magnet support structure is provided with a magnet position adjustment mechanism to adjust the horizontal position and attitude of the magnet to be tested, so that the axis of the magnet hole coincides with the vertical measurement direction; the motion mechanism includes x-direction motion mechanism displacement adjustment, y-direction motion mechanism displacement adjustment and motion mechanism horizontal adjustment, to adjust the lateral position and horizontal attitude of the vertical line take-up mechanism.

[0008] Furthermore, the motion mechanism also includes a vertical motion motor and a vertical motion track. The plumb line take-up mechanism is set on the vertical motion track and can move vertically along the vertical motion track under the drive of the vertical motion motor. The motion mechanism is also equipped with a tank chain for laying the system's connecting cables.

[0009] Furthermore, the plumb line take-up mechanism includes a plumb line take-up motor and a winding wheel. The plumb line is wound on the winding wheel, and the plumb line take-up motor drives the winding wheel to rotate, thereby releasing and retracting the plumb line. The plumb line is a non-magnetic, low-elongation, low-heat-shrinkage, and dimensionally stable flexible wire. The flexible wire includes one of aramid fiber, PBO fiber, LCP liquid crystal polymer fiber, quartz fiber, glass fiber, or non-metallic composite fiber.

[0010] Furthermore, the gravity hammer is a non-magnetic gravity hammer with a weight range of 50g-200g; the target ball is made of ceramic and is set at the tip of the gravity hammer and located on the axis of the gravity hammer; the center of the target ball and the sensitive area of ​​the three-dimensional Hall probe have a pre-calibrated relative positional relationship, and the actual spatial position of the sensitive area of ​​the three-dimensional Hall probe can be determined in conjunction with the spatial measurement device.

[0011] Secondly, this application proposes a method for measuring the axial magnetic field distribution of the aforementioned vertical hole shaft magnet using a vertical measurement system, comprising the following steps: Step 1: Install the magnet to be tested on the magnet support structure. Adjust the position and orientation of the magnet to be tested by adjusting the position of the magnet to be tested on the magnet support structure so that the hole axis of the magnet to be tested coincides with the vertical measurement direction, and establish a measurement coordinate system with the hole axis of the magnet as the reference. Step 2: Install the three-dimensional Hall probe at the lower end of the plumb line, and set a gravity hammer and a target ball at the lower end of the plumb line. The gravity hammer keeps the plumb line taut and forms a plumb line measurement reference. Step 3: Measure the spatial position of the target ball's center using a spatial measurement device, and determine the actual position of the three-dimensional Hall probe's sensitive area in the measurement coordinate system by combining the pre-calibrated relative positional relationship between the target ball's center and the three-dimensional Hall probe's sensitive area. Step four: Control the release or retraction of the plumb line through the plumb line take-up mechanism, thereby moving the three-dimensional Hall probe along the hole axis of the magnet to be tested; Step 5: During the movement of the three-dimensional Hall probe along the axis of the magnet hole, the motion controller synchronously records the length of the vertical line extension and retraction, the position of the motion mechanism, and the output signal of the three-dimensional Hall probe. The data acquisition unit obtains the axial magnetic field distribution curve of the magnet based on the probe position and magnetic field strength data.

[0012] Furthermore, when it is necessary to obtain the spatial magnetic field distribution, the lateral position of the three-dimensional Hall probe relative to the magnet axis is changed by adjusting the displacement of the x-direction motion mechanism and the y-direction motion mechanism. The axial scanning process is repeated at different lateral positions to finally obtain the three-dimensional magnetic field spatial distribution in and around the magnet hole.

[0013] Furthermore, the vertical measurement method for the axial magnetic field distribution of a vertical hole shaft magnet is characterized by including a line length calibration step before formal testing: establishing a calibration relationship between the motor rotation angle and winding layer number of the vertical line take-up mechanism and the actual take-up and unwinding length of the vertical line using a standard displacement measuring device, laser tracker, or grating ruler; and compensating for the axial position of the three-dimensional Hall probe during testing based on the calibration relationship.

[0014] Furthermore, during the measurement process, the swaying of the plumb line and external vibrations are suppressed: a stabilization waiting time is set before measurement to allow the swaying of the gravity hammer and the plumb line to decay to an allowable range; and / or the impact of swaying on the measurement results is reduced through damping structures, guide limiting structures, low-speed unidirectional scanning methods, or data filtering methods; for high-precision measurement scenarios, sampling points with sway amplitude exceeding a preset threshold are removed during data acquisition.

[0015] Furthermore, the measurement consistency is verified by using a reciprocating scan or repeated scan method. By comparing the magnetic field distribution curves obtained from different scanning directions or multiple repeated scans, the system measurement repeatability is judged and abnormal measurement points are identified. Abnormal measurement points are then corrected or re-acquired.

[0016] Compared with existing technologies, the vertical measurement system and method for the axial magnetic field distribution of a vertical hole shaft magnet proposed in this application have the following advantages: (1) This application uses a gravity hammer to keep the plumb line taut and form a plumb line measurement reference. The flexible plumb line carries the three-dimensional Hall probe to complete the axial scan, avoiding the position and attitude deviation caused by the bending deformation of the rigid long rod. This achieves the effect of improving the positioning accuracy of the probe and improving the reliability of the axial magnetic field measurement results.

[0017] (2) This application controls the extension and retraction of the plumb line through the plumb line retraction mechanism to drive the probe to move. It can cover a long test range without the need to configure a large stroke vertical motion mechanism, thereby reducing the overall height of the equipment and adapting to test sites with limited clearance.

[0018] (3) This application uses a target ball to calibrate the spatial position of the sensitive area of ​​the three-dimensional Hall probe, and with the lateral adjustment function of the motion mechanism and various error correction methods, it achieves the effect of improving the consistency of measurement data, obtaining the spatial distribution of the three-dimensional magnetic field, and adapting to the testing needs of various vertical hole shaft magnets. Attached Figure Description

[0019] The accompanying drawings, which form part of this application, are used to provide a further understanding of this application. The illustrative embodiments and descriptions of this application are used to explain this application and do not constitute an undue limitation of this application. In the drawings: Figure 1 This is a schematic diagram of the forward structure of the vertical measurement system for the axial magnetic field distribution of the vertical hole shaft magnet described in the embodiments of this application; Figure 2 This is a schematic diagram of the lateral structure of the vertical measurement system for the axial magnetic field distribution of the vertical hole shaft magnet described in the embodiments of this application; Figure 3 This is a flowchart illustrating the steps of the vertical measurement method for the axial magnetic field distribution of a vertical hole shaft magnet as described in the embodiments of this application.

[0020] Explanation of reference numerals in the attached figures: 1. Motion mechanism; 2. Magnet support structure; 3. Vertical line take-up mechanism; 4. Magnet to be tested; 5. Vertical motion motor; 6. Vertical motion track; 7. Vertical line take-up motor; 8. Tank chain; 9. Displacement adjustment of the x-direction motion mechanism; 10. Displacement adjustment of the y-direction motion mechanism; 11. Horizontal adjustment of the motion mechanism; 12. Vertical line; 13. Position adjustment of the magnet to be tested; 14. Gravity hammer; 15. Target ball; 16. Three-dimensional Hall probe. Detailed Implementation

[0021] To make the technical solution and advantages of 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 not intended to limit the scope of this application.

[0022] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other.

[0023] Furthermore, it should be noted that in the description of this application, if terms such as "upper," "lower," "inner," or "outer" appear, indicating orientation or positional relationship, these are based on the orientation or positional relationship shown in the accompanying drawings and are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation on this application. In addition, if terms such as "first" or "second" appear, they are also used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0024] Furthermore, in the description of this application, unless otherwise expressly defined, the terms "installation," "connection," "joining," and "connector" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; 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; and they can refer to the internal connection between two components. Those skilled in the art can understand the specific meaning of the above terms in this application in light of the specific circumstances.

[0025] In this application, the terms "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., refer to a specific feature, structure, material, or characteristic described in connection with that embodiment or example, which is included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0026] The present application will now be described in detail through exemplary embodiments. However, it should be understood that, without further description, elements, structures, and features in one embodiment may be advantageously incorporated into other embodiments.

[0027] During the development, installation, and acceptance of magnets, excitation and magnetic field distribution tests are typically required. For magnets with a vertical beam, their axis is often arranged vertically due to structural installation posture, cooling methods, or operating conditions. The magnetic field testing device needs to measure the axial magnetic field distribution along the vertical axis. Currently, most conventional magnetic field testing systems are suitable for horizontal magnetic field testing, typically using a horizontal motion mechanism to move a Hall probe or other induction coil along the magnet's axis. Some special magnets also utilize coil rotation testing systems. For magnets with a vertically arranged axis, using a traditional rod-type measurement scheme, with a rigid measuring rod carrying the Hall probe for vertical scanning, has significant limitations when measuring large-scale axial magnetic fields. Firstly, large-scale measurements require a large-stroke vertical motion mechanism, increasing the overall height of the equipment and making it susceptible to limitations imposed by the test site's clearance. Secondly, the long, rigid measuring rod is prone to bending deformation due to its own weight, machining straightness, assembly errors, and external disturbances. Small deviations at the rod end amplify with the rod's length, causing the Hall probe's sensitive area to deviate from the intended measurement position. Simultaneously, probe attitude deviation also affects the accuracy of magnetic field component measurements. These errors are difficult to eliminate effectively through simple adjustments. To address these problems, this application proposes the following specific embodiments.

[0028] Example 1 Reference Figure 1 and Figure 2This embodiment provides a vertical measurement system for the axial magnetic field distribution of a vertical hole-axis magnet, including a magnet support structure 2, a motion mechanism 1, a plumb line winding mechanism 3, a plumb line 12, a gravity hammer 14, a target ball 15, a three-dimensional Hall probe 16, a motion controller, and a data acquisition unit. The magnet support structure 2 is used to mount the magnet to be measured 4. This embodiment uses the magnet to be measured 4 as an example for explanation. In practical applications, it can also be adapted to room temperature magnets, electronic internal target magnets, vertical temperature hole magnets, and other magnets with their axes arranged vertically. The hole axis of the magnet to be measured 4 is arranged vertically. The motion mechanism 1 is located above the magnet support structure 2, and the plumb line winding mechanism 3 is located on the motion mechanism 1, allowing its spatial position to be adjusted with the motion mechanism 1. One end of the plumb line 12 is wound and connected to the plumb line winding mechanism 3, and the other end extends downwards in the vertical direction. The gravity hammer 14 is connected to the lower end of the plumb line 12 to keep the plumb line 12 taut and form a vertical measurement reference. A three-dimensional Hall effect probe 16 is positioned at the lower end of a plumb line 12 and moves vertically as the plumb line 12 is extended and retracted. A target ball 15 is mounted on a gravity hammer 14 and is used to calibrate the spatial position of the sensitive area of ​​the three-dimensional Hall effect probe 16. A motion controller is electrically connected to both the motion mechanism 1 and the plumb line retraction mechanism 3, and is used to control the extension and retraction of the plumb line 12 and the position adjustment of the motion mechanism 1. A data acquisition unit is electrically connected to the three-dimensional Hall effect probe 16 and is used to synchronously acquire probe position data and magnetic field strength data to obtain the axial magnetic field distribution of the magnet.

[0029] To adjust the position and orientation of the magnet, the magnet support structure 2 in this embodiment is equipped with a magnet position adjustment 13, which is used to adjust the horizontal position and orientation of the magnet 4 to make the magnet hole axis coincide with the vertical measurement direction. Based on the invention objective of improving the lateral position adjustment capability of the probe, in this embodiment, the motion mechanism 1 includes an x-direction motion mechanism displacement adjustment 9, a y-direction motion mechanism displacement adjustment 10, and a motion mechanism horizontal adjustment 11, which are used to adjust the lateral position and horizontal orientation of the vertical line take-up mechanism 3, thereby changing the lateral position of the three-dimensional Hall probe 16 relative to the magnet axis to meet the measurement requirements of different lateral positions.

[0030] Reference Figure 2 The motion mechanism 1 in this embodiment also includes a vertical motion motor 5 and a vertical motion track 6. A plumb line take-up mechanism 3 is mounted on the vertical motion track 6 and can move vertically along the vertical motion track 6 under the drive of the vertical motion motor 5. The vertical motion track 6 provides auxiliary vertical displacement compensation, and, in conjunction with the take-up and take-up actions of the plumb line 12, covers a larger axial measurement range. A tank chain 8 is also provided on the motion mechanism 1 for laying the system's connecting cables. This chain protects and guides the cables when the motion mechanism 1 is adjusted, preventing cable pulling from affecting measurement stability.

[0031] To achieve stable deployment and retraction of the plumb line 12, the plumb line take-up mechanism 3 in this embodiment includes a plumb line take-up motor 7 and a winding wheel. The plumb line 12 is wound on the winding wheel, and the plumb line take-up motor 7 drives the winding wheel to rotate, thereby enabling the deployment and retraction of the plumb line 12. The plumb line take-up motor 7 can be a servo motor or a stepper motor. By controlling the rotation angle of the winding wheel, the length of the deployed and retracted line can be controlled, supporting a large axial testing range within a small equipment space. Based on the objective of ensuring measurement position accuracy, in this embodiment, the plumb line 12 is a non-magnetic, low-elongation, low-thermal-shrinkage, and dimensionally stable flexible wire. The flexible wire includes one of the following: aramid fiber, PBO fiber, LCP liquid crystal polymer fiber, quartz fiber, glass fiber, or non-metallic composite fiber. This type of wire does not interfere with the magnetic field measurement results and has small deformation under external tension and temperature changes, maintaining the stability of the wire length over a long period and reducing position measurement errors caused by environmental factors. Unlike rigid measuring rods, flexible plumb lines 12 primarily bear tensile forces rather than bending moments. Under the action of gravity hammers 14, they can form stable plumb lines, reducing deflection errors caused by straightness issues in long rod machining and assembly deviations.

[0032] To ensure both the tension and measurement accuracy of the plumb line 12, the gravity hammer 14 in this embodiment is a non-magnetic gravity hammer with a weight range of 50g to 200g. This weight range provides sufficient tension to maintain a stable plumb line 12 without causing significant elongation or deformation due to excessive tension, thus balancing tension and dimensional accuracy. The target ball 15 is a 0.5-inch ceramic ball, positioned at the tip of the gravity hammer 14 and located on its axis, ensuring positional accuracy during manufacturing. The center of the target ball 15 and the sensitive area of ​​the three-dimensional Hall probe 16 have a pre-calibrated relative positional relationship, which, in conjunction with a spatial measurement device, allows determination of the actual spatial position of the sensitive area of ​​the three-dimensional Hall probe 16.

[0033] During the commissioning phase after system assembly, a nuclear magnetic resonance gaussmeter was used to calibrate the three-dimensional Hall probe 16, ensuring that the magnetic field measurement accuracy was no greater than 0.01%. Subsequently, a laser tracker was used to collimate and position the magnet 4 suspended on the magnet support structure 2, establishing a coordinate system with the magnet's central axis as the Z-axis, ensuring that the parallelism error between the magnet's axis and the horizontal plane was no greater than 0.01°. The plumb line take-up mechanism 3 had a take-up displacement accuracy of no more than 0.01 mm and a repeatability accuracy of ±5 micrometers. Combined with the feedback positioning from the ceramic target ball 15 and the laser tracker, the spatial overlap error between the sensitive area of ​​the three-dimensional Hall probe 16 and the mechanical position of the field distribution was no greater than 100 micrometers. Simultaneously, the axial positioning accuracy of the probe under strong fields was ensured to be ±0.01 mm, with the angle controlled within 0.05°. After positioning and locking, the plumb line take-up mechanism 3 was activated, which could control the micro-displacement amplitude caused by external vibrations to within 2 micrometers, reducing the impact of environmental interference.

[0034] This embodiment uses a flexible plumb line 12 instead of a traditional rigid measuring rod, structurally avoiding position and orientation deviations caused by bending deformation, effectively improving the positioning accuracy and measurement repeatability of the three-dimensional Hall probe 16. Simultaneously, the plumb line 12's retractable measurement method eliminates the need for a vertical motion mechanism of equal length to the test range, effectively reducing the overall height of the equipment, lowering structural complexity, and adapting to testing environments with limited clearance. Combined with target ball 15 calibration and multi-dimensional error correction methods, the positioning accuracy and data consistency of the measurement system can be further improved, adapting to the testing needs of various types of vertical hole-shaft magnets.

[0035] Example 2 Reference Figure 3 This embodiment provides a vertical measurement method for the axial magnetic field distribution of a vertical hole shaft magnet, applied to the vertical measurement system for the axial magnetic field distribution of a vertical hole shaft magnet described in the above embodiment, and includes the following steps.

[0036] Step 1: Install the magnet to be tested 4 on the magnet support structure 2. Adjust the position and orientation of the magnet to be tested 4 by adjusting the position of the magnet to be tested 13 on the magnet support structure 2 so that the hole axis of the magnet to be tested 4 coincides with the vertical measurement direction, and establish a measurement coordinate system with the hole axis of the magnet as the reference.

[0037] Step 2: Install the three-dimensional Hall probe 16 at the lower end of the plumb line 12, and set a gravity hammer 14 and a target ball 15 at the lower end of the plumb line 12. The gravity hammer 14 keeps the plumb line 12 taut and forms a plumb measurement reference.

[0038] Step 3: Measure the spatial position of the center of the target ball 15 using a spatial measurement device. Combine this with the pre-calibrated relative positional relationship between the center of the target ball 15 and the sensitive area of ​​the three-dimensional Hall probe 16 to determine the actual position of the sensitive area of ​​the three-dimensional Hall probe 16 in the measurement coordinate system.

[0039] Step four: The plumb line 12 is released or retracted by the plumb line take-up mechanism 3, which drives the three-dimensional Hall probe 16 to move along the hole axis of the magnet 4 to be tested.

[0040] Step 5: During the movement of the three-dimensional Hall probe 16 along the axis of the magnet hole, the motion controller synchronously records the length of the vertical line 12, the position of the motion mechanism 1, and the output signal of the three-dimensional Hall probe 16. The data acquisition unit obtains the axial magnetic field distribution curve of the magnet based on the probe position and magnetic field strength data.

[0041] To obtain the magnetic field distribution within a spatial range, when the spatial magnetic field distribution is required, the lateral position of the three-dimensional Hall probe 16 relative to the magnet axis is changed by adjusting the displacement of the x-direction motion mechanism 9 and the y-direction motion mechanism 10. The axial scanning process is repeated at different lateral positions to ultimately obtain the three-dimensional spatial distribution of the magnetic field within and near the magnet hole. The measurement process can be fully automated through a motion controller, resulting in a three-dimensional magnetic field spatial distribution model. Data visualization is achieved through a corresponding software platform, facilitating subsequent data processing and test report generation. The scanning rate can be adjusted from 0.1 mm / s to 5 mm / s, and the corresponding rate can be selected to perform unidirectional upward motion according to the required testing accuracy and efficiency. The step size can be set according to physical requirements.

[0042] To improve the accuracy of axial position measurement, this embodiment includes a line length calibration step before formal testing. Since the winding radius of the measuring line may change with the number of winding layers during the winding process, the motor angle and the actual winding and unwinding length of the measuring line may not maintain a strictly linear relationship. Therefore, a calibration relationship is established between the motor angle and the number of winding layers of the plumb line winding mechanism 3 and the actual winding and unwinding length of the plumb line 12 using a standard displacement measuring device, laser tracker, or grating ruler. During testing, the axial position of the three-dimensional Hall probe 16 is compensated based on this calibration relationship. This calibration step can correct the line length calculation error caused by changes in the winding radius, effectively improving the measurement accuracy of the axial position.

[0043] To reduce the impact of external interference on the measurement results, the swaying of the plumb line 12 and external vibrations are suppressed during the measurement process. A stabilization waiting time is set before measurement to allow the swaying of the gravity hammer 14 and the plumb line 12 to decay to an allowable range. The impact of swaying on the measurement results can also be reduced through damping structures, guide and limiting structures, low-speed unidirectional scanning methods, or data filtering. For high-precision measurement scenarios, sampling points with sway amplitudes exceeding a preset threshold are discarded during data acquisition to ensure the validity of the sampled data.

[0044] To verify the reliability of the measurement results, a reciprocating scan or repeated scan method is used to check the measurement consistency. By comparing the scan results from bottom to top and top to bottom, or the magnetic field distribution curves obtained from multiple repeated scans, the system's measurement repeatability is determined and abnormal measurement points are identified. Abnormal measurement points are then corrected or re-acquired. This step can further improve the consistency and reliability of the measurement data and reduce the impact of random errors and external disturbances on the test results.

[0045] The above descriptions are merely some embodiments of this application and are not intended to limit this application. The technical features or structures in the foregoing different embodiments can be arbitrarily combined to form other specific technical solutions as needed. For those skilled in the art, this application can have various modifications and variations. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the scope of protection of the claims of this application.

Claims

1. A vertical measurement system for the axial magnetic field distribution of a vertical hole shaft magnet, characterized in that, include: A magnet support structure (2) is used to install the magnet to be tested (4), wherein the hole axis of the magnet to be tested (4) is arranged in the vertical direction; The motion mechanism (1) is located above the magnet support structure (2); A plumb line take-up mechanism (3) is mounted on the motion mechanism (1) and can adjust its spatial position with the motion mechanism (1); A plumb line (12) has one end wound and connected to the plumb line take-up mechanism (3), and the other end extends downward in the vertical direction. A gravity hammer (14) is connected to the lower end of the plumb line (12) to keep the plumb line (12) taut and form a plumb measurement reference. A three-dimensional Hall probe (16) is set at the lower end of the vertical line (12) and moves in the vertical direction as the vertical line (12) is extended or retracted. A target ball (15) is placed on the gravity hammer (14) to calibrate the spatial position of the sensitive area of ​​the three-dimensional Hall probe (16); The motion controller is electrically connected to the motion mechanism (1) and the vertical line take-up mechanism (3) respectively, and is used to control the take-up and take-up actions of the vertical line (12) and the position adjustment of the motion mechanism (1); The data acquisition unit is electrically connected to the three-dimensional Hall probe (16) and is used to synchronously acquire probe position data and magnetic field strength data to obtain the axial magnetic field distribution of the magnet.

2. The vertical measurement system for the axial magnetic field distribution of a vertical hole shaft magnet according to claim 1, characterized in that, The magnet support structure (2) is provided with a magnet position adjustment (13) for adjusting the horizontal position and attitude of the magnet (4) to make the magnet hole axis coincide with the vertical measurement direction; the motion mechanism (1) includes x-direction motion mechanism displacement adjustment (9), y-direction motion mechanism displacement adjustment (10) and motion mechanism horizontal adjustment (11) for adjusting the lateral position and horizontal attitude of the vertical line take-up mechanism (3).

3. The vertical measurement system for the axial magnetic field distribution of a vertical hole shaft magnet according to claim 1, characterized in that, The motion mechanism (1) also includes a vertical motion motor (5) and a vertical motion track (6). The plumb line take-up mechanism (3) is set on the vertical motion track (6) and can move vertically along the vertical motion track (6) under the drive of the vertical motion motor (5). The motion mechanism (1) is also equipped with a tank chain (8) for laying the system's connecting cables.

4. The vertical measurement system for the axial magnetic field distribution of a vertical hole shaft magnet according to claim 1, characterized in that, The plumb line take-up mechanism (3) includes a plumb line take-up motor (7) and a winding wheel. The plumb line (12) is wound on the winding wheel. The plumb line take-up motor (7) is used to drive the winding wheel to rotate, so as to release and retract the plumb line (12). The plumb line (12) is a non-magnetic, low elongation, low thermal shrinkage and dimensionally stable flexible wire. The flexible wire includes one of aramid fiber, PBO fiber, LCP liquid crystal polymer fiber, quartz fiber, glass fiber or non-metallic composite fiber.

5. The vertical measurement system for the axial magnetic field distribution of a vertical hole shaft magnet according to claim 1, characterized in that, The gravity hammer (14) is a non-magnetic gravity hammer with a weight range of 50g-200g; the target ball (15) is made of ceramic material, is set at the tip of the gravity hammer (14) and located on the axis of the gravity hammer (14); the center of the target ball (15) and the sensitive area of ​​the three-dimensional Hall probe (16) have a pre-calibrated relative position relationship, and the actual spatial position of the sensitive area of ​​the three-dimensional Hall probe (16) can be determined with the help of a spatial measurement device.

6. A method for vertically measuring the axial magnetic field distribution of a vertical hole shaft magnet, applied to the vertical measurement system for the axial magnetic field distribution of a vertical hole shaft magnet as described in any one of claims 1 to 5, characterized in that, Includes the following steps: Step 1: Install the magnet to be tested (4) on the magnet support structure (2), and adjust the position and orientation of the magnet to be tested (4) by adjusting the position of the magnet to be tested (4) on the magnet support structure (2) (13) so that the hole axis of the magnet to be tested (4) coincides with the vertical measurement direction, and establish a measurement coordinate system with the magnet hole axis as the reference. Step 2: Install the three-dimensional Hall probe (16) at the lower end of the plumb line (12), and set a gravity hammer (14) and a target ball (15) at the lower end of the plumb line (12). The gravity hammer (14) keeps the plumb line (12) taut and forms a plumb measurement reference. Step 3: Measure the spatial position of the center of the target ball (15) using a spatial measurement device, and determine the actual position of the sensitive area of ​​the three-dimensional Hall probe (16) in the measurement coordinate system by combining the pre-calibrated relative positional relationship between the center of the target ball (15) and the sensitive area of ​​the three-dimensional Hall probe (16). Step 4: Control the plumb line (12) to be released or retracted by the plumb line take-up mechanism (3), thereby driving the three-dimensional Hall probe (16) to move along the hole axis of the magnet (4) to be tested; Step 5: During the movement of the three-dimensional Hall probe (16) along the axis of the magnet hole, the motion controller synchronously records the length of the vertical line extension and retraction, the position of the motion mechanism and the output signal of the three-dimensional Hall probe (16). The data acquisition unit obtains the magnetic field distribution curve of the magnet axial direction based on the probe position and magnetic field strength data.

7. The vertical measurement method for the axial magnetic field distribution of a vertical hole shaft magnet according to claim 6, characterized in that, When it is necessary to obtain the spatial magnetic field distribution, the lateral position of the three-dimensional Hall probe (16) relative to the magnet axis is changed by adjusting the displacement of the x-direction motion mechanism (9) and the y-direction motion mechanism (10). The axial scanning process is repeated at different lateral positions to finally obtain the three-dimensional magnetic field spatial distribution in the magnet hole and the area near the hole.

8. The vertical measurement method for the axial magnetic field distribution of a vertical hole shaft magnet according to claim 6, characterized in that, Before the formal test, a line length calibration step is also included: by using a standard displacement measuring device, laser tracker or grating ruler, a calibration relationship is established between the motor rotation angle and the number of winding layers of the vertical line take-up mechanism (3) and the actual take-up and unwinding length of the vertical line (12). During the test, the axial position of the three-dimensional Hall probe (16) is compensated according to the calibration relationship.

9. A method for vertically measuring the axial magnetic field distribution of a vertical hole shaft magnet according to claim 6, characterized in that, During the measurement process, the swaying of the plumb line (12) and external vibrations are suppressed: a stabilization waiting time is set before measurement to reduce the swaying of the gravity hammer (14) and the plumb line (12) to an allowable range; and / or the influence of swaying on the measurement results is reduced by damping structure, guide limit structure, low-speed unidirectional scanning method or data filtering method; for high-precision measurement scenarios, sampling points with sway amplitude exceeding the preset threshold are removed during data acquisition.

10. The vertical measurement method for the axial magnetic field distribution of a vertical hole shaft magnet according to claim 6, characterized in that, Measurement consistency is verified by using a reciprocating scan or repeated scan method. By comparing the magnetic field distribution curves obtained from different scanning directions or multiple repeated scans, the system measurement repeatability is judged and abnormal measurement points are identified. Abnormal measurement points are then corrected or re-acquired.

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