A system and method for eddy current testing of dynamic properties of flight chains

Abstract

The present application relates to the technical field of nondestructive testing, and provides a kind of dynamic characteristic eddy current detection system and method of scraper chain to solve the problems of low detection efficiency, unable to measure tension and speed synchronously, and probe is easily damaged in harsh environment and inconvenient to maintain, etc.The technical scheme of the system mainly includes: probe detection unit, adopts built-in iron core array coil layout, synchronously induces dynamic eddy current determined by chain speed and induced eddy current caused by tension change;Detection protection unit is provided with upper and lower open and close maintenance opening for quick maintenance;And detection lift-off regulation unit can accurately adjust the distance between probe and chain.The present application can realize the online synchronization, high-precision monitoring of scraper chain tension and speed, significantly improve the detection efficiency and reliability, and at the same time enhance the environmental adaptability and maintenance convenience of the system, and provide effective support for intelligent operation and maintenance of scraper conveyor.

Description

Technical Field

[0001] This invention relates to the field of nondestructive testing technology, specifically to an eddy current testing system and method for the dynamic characteristics of a scraper chain. Background Technology

[0002] Driven by emerging technologies such as artificial intelligence, big data, and the Internet of Things, intelligent operation and maintenance technology for scraper conveyors is rapidly developing towards high-precision monitoring and system-wide collaboration. On the one hand, monitoring technology, through multi-source data fusion and algorithm optimization, enables early warning of minor faults, significantly improving the reliability of equipment operation. On the other hand, the deep integration of intelligent operation and maintenance systems with all aspects of coal mine production is promoting the transformation of coal mine production towards a fully automated and intelligent ecosystem.

[0003] However, existing technologies still have the following key problems: 1. When conveying materials, scraper chains need to be completely buried in the bulk materials. During operation, the dynamic characteristics such as material impact and chain vibration are complex. Traditional detection methods based on physical sensors have the defects of low detection efficiency and slow response. Especially under harsh working conditions, the sensor probes are easily damaged by wear, corrosion or impact, resulting in data distortion or interruption. When a sensor failure occurs, traditional detection and protection units need to stop the machine and disassemble the equipment to locate the fault point. The maintenance process is time-consuming and relies on manual experience, which not only leads to low maintenance efficiency, but also affects the continuity of production due to long-term equipment downtime. In addition, repeated disassembly and assembly may further reduce the sensor installation accuracy, forming a vicious cycle of "failure-maintenance-accuracy decline".

[0004] Therefore, how to overcome the physical limitations of traditional detection technologies and develop a non-contact, highly robust online detection system and method to achieve real-time perception of the dynamic characteristics of scraper chains and self-diagnosis of faults has become the key to improving the intelligence level of coal mine transportation systems. Summary of the Invention

[0005] In order to solve at least one of the above-mentioned technical problems in the prior art, the present invention provides a scraper chain dynamic characteristic eddy current detection system and method.

[0006] In a first aspect, the present invention provides a scraper chain dynamic characteristic eddy current detection system, comprising: a probe detection unit, a detection protection unit, a detection lifting control unit, and a host computer;

[0007] The probe detection unit includes an excitation coil, a detection coil, and an iron core. The excitation coil and the detection coil are arranged in an array, with the excitation coil on the inner side and the detection coil on the outer side. Both the excitation coil and the detection coil are array structures composed of multiple independent coil units. The iron core is vertically arranged at the center of the excitation coil. The coil units of each excitation coil are connected in series to generate an alternating magnetic field. The coil units of each detection coil are connected in parallel to simultaneously sense the motional eddy current signal determined by the speed of the scraper chain under test, as well as the induced eddy current signal caused by the change in the permeability of the scraper chain under test due to the change in the tension of the scraper chain under test.

[0008] The detection protection unit is used to house and protect the probe detection unit, and is provided with an openable and closable maintenance port.

[0009] The detection and lifting control unit includes a coarse adjustment component and a fine adjustment component for controlling the distance between the probe detection unit and the scraper chain to be tested. The coarse adjustment component is used to realize a large range of adjustment of the distance between the probe detection unit and the scraper chain to be tested, and the fine adjustment component is used to realize a small adjustment of the distance between the probe detection unit and the scraper chain to be tested.

[0010] The host computer is used to receive the motional voltage and induced voltage generated by the detection coil in the probe detection unit based on the motional eddy current signal and the induced eddy current signal, and to calculate the running speed of the scraper chain under test based on the motional voltage, and to calculate the tension on the scraper chain under test based on the induced voltage.

[0011] In one optional embodiment, the detection and protection unit includes a first housing, a first drive motor, a first reel, a first gear, a chain, a diaphragm, and a traction rope;

[0012] The first housing is provided with an openable and closable access port at both the upper and lower parts, and an access port is provided with an access component for sealing the access port.

[0013] Two first spools are provided and are positioned opposite each other at the lower inspection port of the first housing, for winding a film to seal or open the inspection port; the first drive motor is mounted on the first housing and is used to drive one of the first spools to rotate.

[0014] Both first spools are fixedly connected to first gears, and the two first gears are driven by a chain. One end of the film is fixed to the first spool connected to the first drive motor, and the other end of the film is fixedly connected to the traction rope wound around the other first spool. The first drive motor drives the first spool to rotate forward or backward, and drives the other first spool to rotate synchronously through the first gear and chain, thereby driving the film to move in the film channel on the inner surface of the first housing, so as to realize the unfolding or rolling up of the film.

[0015] When the film is in the rolled-up state, the film is wound on the first spool connected to the first drive motor, and the other end of the film is embedded in the film channel on the inner surface of the first housing, and the traction rope is located in the film channel;

[0016] When the film is in the unfolded state, the other end of the film passes through the film channel on the inner surface of the first housing and is wound onto another first spool.

[0017] In one optional embodiment, the maintenance assembly of the maintenance port on the upper part of the first housing includes an upper door panel hinged to the upper edge of the maintenance port, and a lower door panel slidably connected to the lower end of the upper door panel; a handle is fixed on the side of the lower door panel away from the upper door panel, and sliding blocks are fixedly connected to both sides of the lower door panel; a horizontally arranged sliding groove is opened on the side wall of the lower door panel away from the detection and protection unit, and the sliding blocks are slidably connected to the sliding groove.

[0018] In one optional embodiment, a spring is provided in the sliding groove, one end of the spring is fixedly connected to the inner wall of the sliding groove, and the other end is fixedly connected to a baffle. The baffle is connected to the sliding block, and the spring is used to push the sliding block against the inner wall of the detection protection unit through the baffle.

[0019] In one optional implementation, the coarse adjustment component in the detection lift-off control unit includes: a second drive motor, a second reel, a second gear, and a rack;

[0020] The output shaft of the second drive motor is connected to the second reel via a coupling, providing power for wide-range adjustment;

[0021] The second gear is fixedly installed in the middle of the second reel and rotates synchronously with the second reel;

[0022] The rack is connected to the first housing of the detection and protection unit and is disposed on one side of the second gear and meshes with the second gear. When the second gear rotates, it drives the rack to move in a straight line, thereby driving the probe detection unit to move to perform the initial adjustment of the distance between the probe detection unit and the scraper chain to be tested.

[0023] In one optional implementation, the detection lift-off control unit further includes a second housing;

[0024] The rack is connected to the second housing by bolts.

[0025] In one optional embodiment, the fine-tuning component in the detection lift-off control unit includes: a horizontal plate, a spiral adjuster, and a fastening bolt; the spiral adjuster includes a top knob, an internal screw, an internal nut, a moving block, a guide rod, a hollow guide post, and a housing; the internal screw is threadedly connected to the internal nut; a moving block is fixedly connected to one side of the internal nut, and a groove is provided on the housing corresponding to the position of the moving block; the other end of the moving block is fixedly connected to the first housing; the upper end of the guide rod is fixedly connected to the lower end of the housing, and the lower end of the guide rod is slidably connected to the hollow guide post. In the hollow guide column, the hollow guide column is fixedly connected to the horizontal plate through a connecting block. The side wall of the hollow guide column is provided with a threaded hole. After the initial adjustment, the guide rod can be fixed by a fastening bolt threaded into the threaded hole. When the top knob is adjusted, the internal screw rotates, driving the internal nut and the moving block to move up and down, thereby driving the first housing connected to the moving block to move up and down, realizing the secondary adjustment control of the distance between the probe detection unit and the scraper chain to be tested. The horizontal plate is fixedly connected to the second housing and is located below the probe detection unit.

[0026] Secondly, the present invention provides a method for detecting the dynamic characteristics of a scraper chain using eddy currents, which can be applied to the first aspect and any optional embodiments, and includes the following steps:

[0027] S1: Control the excitation coil in the probe detection unit to pass an alternating current with preset parameters to generate an alternating magnetic field;

[0028] S2: Collect the motional eddy current signal generated by the scraper chain under test cutting magnetic field lines when it moves in the alternating magnetic field and convert it into motional voltage;

[0029] S3: Collect the induced eddy current signal generated by the change in magnetic permeability of the scraper chain under test when the scraper chain under test moves in the alternating magnetic field and convert it into the induced voltage;

[0030] S4: Based on the dynamic voltage and induced voltage, and according to the preset speed-voltage relationship model and the preset tension-voltage relationship model, the real-time running speed and real-time tension of the scraper chain under test during its motion are calculated.

[0031] In one optional implementation, prior to step S1, the method further includes:

[0032] The optimal lift-off distance between the probe detection unit and the scraper chain under test is determined by COMSOL simulation. Then, the probe detection unit is moved to a position close to the optimal lift-off distance by the coarse adjustment component of the detection lift-off control unit. Finally, the probe detection unit is precisely adjusted to the optimal lift-off distance by the fine adjustment component.

[0033] In an optional implementation, step S4 further includes:

[0034] The dynamic voltage and induced voltage are processed by a preset signal conditioning circuit, then input into a data acquisition card and converted into digital signals. Then, based on the preset speed-voltage relationship model and the preset tension-voltage relationship model, the real-time running speed and real-time tension of the scraper chain under test are calculated.

[0035] Compared with the prior art, the beneficial effects of the present invention are:

[0036] This application employs an array-type eddy current probe design. By adding an iron core to the excitation coil to enhance the magnetic field strength, and combining the integrated detection principle of motional and induced eddy currents, it achieves synchronous, online, high-precision measurement of two key dynamic parameters—tension and speed—of the scraper chain. This solves the problems of low efficiency and inability to simultaneously detect multiple parameters using traditional methods. Simultaneously, this application designs a detection protection unit that combines protection and convenient maintenance. The unique mechanical structure of its upper and lower maintenance ports greatly simplifies the maintenance process and improves maintenance efficiency. Furthermore, by integrating a detection lift-off control unit consisting of coarse and fine adjustments, and determining the optimal detection distance based on COMSOL simulation, the probe position can be adaptively adjusted, ensuring the stability of the detection signal and the accuracy of the results. Overall, this application significantly improves the reliability, accuracy, and intelligence level of scraper chain condition monitoring, providing strong technical support for the safe and efficient operation and predictive maintenance of scraper conveyors. Attached Figure Description

[0037] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0038] Figure 1 This is a schematic diagram of the overall structure of the eddy current detection system for the dynamic characteristics of a scraper chain provided in an embodiment of the present invention;

[0039] Figure 2 This is a schematic diagram of the maintenance assembly structure of the upper maintenance port according to an embodiment of the present invention;

[0040] Figure 3 This is a structural schematic diagram of the lower inspection port of the first housing according to an embodiment of the present invention;

[0041] Figure 4 This is a schematic diagram of the internal structure of the detection lift-off control unit provided in an embodiment of the present invention;

[0042] Figure 5 yes Figure 2 Enlarged view of point A in the middle;

[0043] Figure 6 yes Figure 4 Enlarged view of point B in the middle;

[0044] Figure 7 This is a schematic diagram of the eddy current detection method for the dynamic characteristics of a scraper chain provided in an embodiment of the present invention;

[0045] Figure 8 The lift-off distance of the probe detection system provided in the embodiment of the present invention affects the voltage of the detection coil. A diagram illustrating the impact;

[0046] Figure 9 This is a magnetic field diagram provided by an embodiment of the present invention when the speed of the scraper chain under test is 0.05 m / s;

[0047] Figure 10 This is an eddy current diagram provided according to an embodiment of the present invention when the speed of the scraper chain under test is 0.05 m / s;

[0048] Figure 11 This is a magnetic field diagram provided according to an embodiment of the present invention when the speed of the scraper chain under test is 0.1 m / s;

[0049] Figure 12 This is an eddy current diagram provided by an embodiment of the present invention when the speed of the scraper chain under test is 0.1 m / s;

[0050] Figure 13 This is a schematic diagram illustrating the influence of the real-time running speed of the scraper chain under test on the dynamic voltage of the detection coil, according to an embodiment of the present invention.

[0051] Figure 14 This is a schematic diagram illustrating the effect of the magnetic permeability of the scraper chain under test on the induced voltage of the detection coil, according to an embodiment of the present invention.

[0052] In the diagram, 1. Upper door panel; 2. Lower door panel; 3. Handle; 4. Rack; 5. Second gear; 6. Second reel; 7. Second drive motor; 8. Spiral adjuster; 9. Horizontal plate; 10. Baffle; 11. Sliding block; 12. Spring; 13. Chain; 14. First gear; 15. First drive motor; 16. Excitation coil; 17. Iron core; 18. Detection coil; 19. Thin film; 20. Probe detection unit; 21. Detection lifting control unit; 22. Scraper chain to be tested; 23. First reel; 24. First housing; 25. Fastening bolt. Detailed Implementation

[0053] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0054] like Figures 1-4 As shown, this embodiment provides a scraper chain dynamic characteristic eddy current detection system, including: a probe detection unit 20, a detection protection unit, a detection lift-off control unit 21, and a host computer;

[0055] The probe detection unit 20 includes an excitation coil 16, a detection coil 18, and an iron core 17. The excitation coil 16 and the detection coil 18 are arranged in an array, with the excitation coil 16 on the inner side and the detection coil 18 on the outer side. Both the excitation coil 16 and the detection coil 18 are array structures composed of multiple independent coil units. The iron core 17 is vertically arranged at the center of the excitation coil 16. The coil units of each excitation coil 16 are connected in series to generate an alternating magnetic field. The coil units of each detection coil 18 are connected in parallel to simultaneously sense the motional eddy current signal determined by the speed of the scraper chain 22 under test, as well as the induced eddy current signal caused by the change in the permeability of the scraper chain 22 under test due to the change in tension of the scraper chain 22 under test.

[0056] In this embodiment, the excitation coil 16 and detection coil 18 of the probe detection unit 20 are arranged in an array. The excitation coil 16 is on the inner side, and the detection coil 18 is on the outer side; both are arrayed from multiple independent coil units. An iron core 17 is added in the middle of the excitation coil 16 to enhance the magnetic field strength. The iron core 17 is made of a soft magnetic material with high permeability, is rectangular in shape, and its length matches the width of the excitation coil 16.

[0057] In this embodiment, the detection coils 18 are connected in parallel. The array of detection coils 18 is used to sense the changes in the secondary magnetic field generated by eddy currents in the scraper chain 22 under test, including the motional eddy currents generated by the movement of the scraper chain 22 under test. Induced eddy currents caused by tension changes .

[0058] In this embodiment, multiple excitation coils 16 are connected in series. After the connection is completed, the entire array of excitation coils 16 is insulated to prevent short circuits. The detection coils 18 are connected in parallel, and insulation measures are also taken. The array of excitation coils 16 and the array of detection coils 18 are assembled together with the excitation coils 16 on the inside and the detection coils 18 on the outside to form a complete probe detection unit 20.

[0059] The detection protection unit is used to house and protect the probe detection unit 20, and is provided with an openable and closable maintenance port.

[0060] In this embodiment, the detection protection unit is installed outside the probe detection unit 20.

[0061] Optionally, the detection and protection unit includes a first housing 24, a first drive motor 15, a first reel 23, a first gear 14, a chain 13, a membrane 19, and a traction rope; the first housing 24 has an openable and closable inspection port at both its upper and lower parts, and each inspection port is equipped with an inspection component for sealing the inspection port; two first reels 23 are provided and are positioned opposite each other at the lower inspection port of the first housing 24, for winding the membrane 19 to seal or open the inspection port; the first drive motor 15 is mounted on the first housing 24 and is used to drive one of the first reels 23 to rotate; both first reels 23 are fixedly connected to the first gear 14, and the two first gears 14 are driven by the chain 13; one end of the membrane 19 is fixed to the first gear 14 connected to the first drive motor 15. On the reel 23, the other end of the film 19 is fixedly connected to the traction rope wound around another first reel 23. The first drive motor 15 drives the first reel 23 to rotate forward or backward, and drives the other first reel 23 to rotate synchronously through the first gear 14 and the chain 13, thereby driving the film 19 to move in the film channel on the inner surface of the first housing 24, realizing the unfolding or rolling up of the film 19. When the film 19 is in the rolled-up state, the film 19 is wound around the first reel 23 connected to the first drive motor 15, and the other end of the film 19 is embedded in the film channel on the inner surface of the first housing 24, and the traction rope is located in the film channel. When the film 19 is in the unfolded state, the other end of the film 19 passes through the film channel on the inner surface of the first housing 24 and is wound around another first reel 23.

[0062] Optionally, the maintenance assembly of the maintenance port on the upper part of the first housing 24 includes an upper door panel 1 hinged to the upper edge of the maintenance port, and a lower door panel 2 slidably connected to the lower end of the upper door panel 1; a handle 3 is fixed on the side of the lower door panel 2 away from the upper door panel 1, and sliding blocks 11 are fixedly connected to both sides of the lower door panel 2; a horizontally arranged sliding groove is opened on the side wall of the lower door panel 2 away from the detection and protection unit, and the sliding blocks 11 are slidably connected to the sliding groove.

[0063] Optionally, a spring 12 is provided in the sliding groove. One end of the spring 12 is fixedly connected to the inner wall of the sliding groove, and the other end is fixedly connected to a baffle 10. The baffle 10 is connected to the sliding block 11, and the spring 12 is used to push the sliding block 11 against the inner wall of the detection protection unit through the baffle 10.

[0064] In this embodiment, as Figure 3 The diagram shows the structure of the lower inspection port of the first housing 24. To clearly show the internal structure of the probe detection unit 20, only half of the area of ​​the lower inspection port covered by the thin film 19 is drawn.

[0065] When the lower part of the probe detection unit 20 is damaged, the first drive motor 15 is activated, driving one of the first spools 23 to rotate around its own axis. Since the first spool 23 is fixedly mounted with the first gear 14, when the first spool 23 rotates, the first gear 14 rotates synchronously with the first spool 23. The rotating first gear 14 meshes with the chain 13, thereby driving the chain 13 to move synchronously. When the chain 13 moves, it drives the other first gear 14 to rotate, so that the other first spool 23 rotates synchronously with the first gear 14, ultimately achieving the same rotation of the two first spools 23. The film 19 is pre-tensioned and wound around the first spool 23 driven by the first drive motor 15. When the two first spools 23 rotate, the traction rope wound around the other first spool 23 is synchronously wound and unwound, thereby driving the film 19 wound around the first spool 23 driven by the first drive motor 15 to unfold or roll up.

[0066] When the first drive motor 15 drives the first reel 23 to rotate in the "unwinding direction", the film 19 is gradually released, and the traction rope on the other first reel 23 is retrieved, so that the film 19 moves along the film channel towards the other first reel 23 under the guidance of the film channel. During the movement, the film 19 always adheres to the inner surface of the first housing 24 to avoid displacement. Finally, the other end of the film 19 passes through the film channel and is wrapped around the other first reel 23, completely covering the lower inspection port of the first housing 24, thus achieving a seal.

[0067] When the first drive motor 15 drives the first spool 23 to reverse in the "winding direction", the film 19 is gradually peeled off from the other first spool 23, so that the film 19 moves back along the film channel towards the first spool 23 that moved first under the guidance and limitation of the film channel; finally, the film 19 no longer blocks the probe detection unit 20, and the other end of the film 19 is located in the film channel, and the inspection port at the bottom of the first housing 24 is opened to facilitate the inspection of the lower part of the probe detection unit 20.

[0068] When the upper part of the probe detection unit 20 is damaged, the inspection port at the top of the detection protection unit can be opened by adjusting the inspection component of the upper inspection port. The damaged part can then be inspected and repaired through this inspection port. In this way, the probe is protected while the inspection efficiency is improved.

[0069] In this embodiment, the film 19 is made of plastic and can be wound around the first roll 23. In actual application, the film channel can be set on both sides of the film 19 in the direction of movement, and the traction rope is set in the film channel so that the film 19 can completely cover the lower inspection port of the first housing 24 when it is unfolded.

[0070] In this embodiment, when inspecting the upper part of the probe detection unit 20, the lower door panel 2 is slid towards the upper door panel 1 relative to the upper door panel 1. The operator pushes the lower door panel 2 with the handle 3, causing the lower door panel 2 to gradually fold into the upper door panel 1. At this time, the vertical cross-section of the inspection component is smaller than the vertical cross-section of the inspection port. Then, the upper door panel 1 and the lower door panel 2 are rotated away from the interior of the detection protection unit, thereby opening the upper door panel 1 and the lower door panel 2. The operation is simple and convenient. Furthermore, when the inspection component blocks the inspection port, sliding block 11 components are provided on both sides of the lower door panel 2. When the inspection component blocks the upper inspection port, the sliding block 11 components can contact the inner wall of the detection protection unit. At this time, the lower door panel 2 is not easily detached from the inspection port. The structure is simple and can achieve the desired effect.

[0071] In this embodiment, when the lower door panel 2 is about to be folded into the upper door panel 1, the sliding block 11 slides in the sliding groove. The sliding block 11 and the sliding groove play a stabilizing role in locking the lower door panel 2.

[0072] In this embodiment, the sliding block 11 is pressed against the inner groove of the detection and protection unit by the elastic force of the spring 12 used for locking, which strengthens the state of the lower door panel 2 in the inspection port.

[0073] In this embodiment, as Figure 5 As shown, for the upper access panel assembly consisting of the upper door panel 1 and the lower door panel 2, the upper door panel 1 is hinged to the upper edge of the access panel via a hinge. The hinge's installation position is precisely adjusted to ensure that the upper door panel 1 can rotate flexibly. The sliding blocks 11 on both sides of the lower door panel 2 have a low coefficient of friction and good wear resistance. Springs 12 are installed in the sliding grooves. The elastic coefficient of the springs 12 is selected according to actual needs. During installation, it is ensured that one end of the spring 12 is tightly fixed to the inner wall of the sliding groove, and the other end is reliably connected to the baffle 10. The baffle 10 is tightly connected to the sliding block 11, so that the sliding block 11 can stably press against the inner groove of the detection and protection unit under the action of the spring 12.

[0074] In this embodiment, for the lower inspection port maintenance assembly, the first reel 23 is made of high-strength aluminum alloy, which has excellent wear resistance and corrosion resistance. The first gear 14 and chain 13 are made of high-quality steel, and their hardness and strength are improved through heat treatment. The film 19 is made of polyester film with certain flexibility and wear resistance. The first drive motor 15 is connected to the first reel 23 through a coupling to ensure the stability of power transmission.

[0075] The detection lifting and control unit 21 includes a coarse adjustment component and a fine adjustment component for controlling the distance between the probe detection unit 20 and the scraper chain 22 to be tested. The coarse adjustment component is used to achieve a wide range of adjustment of the distance between the probe detection unit 20 and the scraper chain 22 to be tested, and the fine adjustment component is used to achieve high-precision micro-adjustment of the distance between the probe detection unit 20 and the scraper chain 22 to be tested.

[0076] Optionally, the coarse adjustment component in the detection lifting control unit 21 includes: a second drive motor 7, a second reel 6, a second gear 5, and a rack 4; the output shaft of the second drive motor 7 is connected to the second reel 6 via a coupling; the second gear 5 is fixedly installed in the middle of the second reel 6 and rotates synchronously with the second reel 6; the rack 4 is connected to the first housing 24 of the detection protection unit and is disposed on one side of the second gear 5 and meshes with the second gear 5. When the second gear 5 rotates, it drives the rack 4 to make linear motion, thereby driving the probe detection unit 20 to move to perform the initial adjustment of the distance between the probe detection unit 20 and the scraper chain 22 to be tested.

[0077] Optionally, the detection and lifting control unit 21 further includes a second housing; the rack 4 is connected to the second housing by bolts.

[0078] Optionally, the fine-tuning component in the detection and lifting control unit 21 includes: a horizontal plate 9, a screw adjuster 8, and a fastening bolt 25; the screw adjuster 8 includes a top knob, an internal screw, an internal nut, a moving block, a guide rod, a hollow guide post, and a housing; the internal screw is threadedly connected to the internal nut; a moving block is fixedly connected to one side of the internal nut, and a groove is provided on the housing corresponding to the position of the moving block; the other end of the moving block is fixedly connected to the first housing 24; the upper end of the guide rod is fixedly connected to the lower end of the housing, and the lower end of the guide rod is slidably connected in the hollow guide post. The hollow guide post is fixedly connected to the horizontal plate 9 via a connecting block. The side wall of the hollow guide post is provided with a threaded hole. After the initial adjustment, the guide rod can be fixed by the fastening bolt 25 threaded into the threaded hole. When the top knob is adjusted, the internal screw rotates, driving the internal nut and the moving block to move up and down, thereby driving the first housing 24 connected to the moving block to move up and down, realizing the secondary adjustment control of the distance between the probe detection unit 20 and the scraper chain 22 to be tested. The horizontal plate 9 is fixedly connected to the second housing and is located below the probe detection unit 20.

[0079] In this embodiment, the second drive motor 7 serves as the power source in the detection and lifting control unit 21, and its output shaft is connected to the second reel 6 to ensure that the torque generated by the second drive motor 7 can be stably and efficiently transmitted to the second reel 6. The second reel 6 has a cylindrical structure, and a second gear 5 is fixedly installed in the middle of the second reel 6. The second gear 5 rotates synchronously with the second reel 6.

[0080] In this embodiment, the rack 4 is bolted to the second housing to form a stable connection structure, thereby ensuring that the movement of the rack 4 can accurately drive the probe detection unit 20 to move synchronously. The rack 4 is located on one side of the second gear 5 and meshes with the second gear 5. When the second gear 5 rotates, the meshing transmission between the two converts the circular motion of the second scroll 6 into the linear motion of the rack 4. The second drive motor 7 drives the second scroll 6 to rotate. When the second scroll 6 rotates, it drives the second gear 5 fixed in its middle to rotate synchronously. At this time, the rack 4, which meshes with the second gear 5, drives the probe detection unit 20 connected to it to move up and down under the drive of the second gear 5, realizing the initial adjustment of the distance between the probe detection unit 20 and the scraper chain 22 to be tested. During the initial adjustment, the guide rod slides in the hollow guide column as the first housing 24 moves up and down.

[0081] In this embodiment, as Figure 6As shown, after the initial adjustment, the operator secures the guide rod with the fastening bolt 25 and simultaneously rotates the top knob of the screw adjuster 8. The rotation of the top knob is transmitted to the internal screw, causing the internal screw to rotate synchronously around its own axis. Since the internal screw and the internal nut are threadedly connected, when the internal screw rotates, the thread engagement drives the internal nut to move linearly along the axis of the internal screw; thereby causing the moving block, which is fixedly connected to one side of the internal nut, to move up and down along the corresponding groove on the outer casing (the groove ensures that the moving block moves only in the vertical direction).

[0082] The other end of the moving block is fixedly connected to the first housing 24. Therefore, the up-and-down movement of the moving block directly drives the first housing 24 to move up and down synchronously. The probe detection unit 20 is installed inside the first housing 24, so the displacement of the first housing 24 directly drives the probe detection unit 20 to move synchronously. When the probe detection unit 20 moves up and down with the first housing 24, the distance between it and the scraper chain 22 under test changes slightly: when the moving block moves upward, it causes the first housing 24 to move upward, thus moving the probe detection unit 20 away from the scraper chain 22; when the moving block moves downward, it causes the first housing 24 to move downward, thus moving the probe detection unit 20 closer to the scraper chain 22. This achieves secondary adjustment control of the distance between the probe detection unit 20 and the scraper chain 22 under test. In practical applications, the distance of the secondary adjustment is very small, generally 0~2 mm.

[0083] In this embodiment, the horizontal plate 9 is a rectangular plate structure made of high-strength aluminum alloy, which is lightweight and high-strength. The horizontal plate 9 is fixed to the second housing, located on the side away from the probe detection unit 20, and connected to the spiral adjuster 8. The spiral adjuster 8 is vertically installed on one side of the probe detection unit 20, and the distance between the probe detection unit 20 and the scraper chain is precisely controlled by a top knob.

[0084] In this embodiment, the second housing is made of cast aluminum, which has good heat dissipation performance and mechanical strength. The second drive motor 7 is selected with appropriate torque and speed, and its output shaft is connected to the second reel 6 through a coupling to ensure reliable power transmission.

[0085] The second gear 5 in the middle of the second reel 6 is interference-fitted with the second reel 6 and further secured by a key to ensure synchronous rotation between the second gear 5 and the second reel 6. The rack 4 is bolted to the second housing. During installation, the meshing clearance between the second gear 5 and the rack 4 is precisely adjusted to ensure transmission accuracy.

[0086] The horizontal plate 9 in the fine-tuning assembly is a rectangular plate structure made of high-strength aluminum alloy, and its dimensions are designed according to the installation requirements of the second housing and the spiral adjuster 8. The horizontal plate 9 is fixedly connected to the second housing with bolts to ensure that the horizontal plate 9 is firmly installed. The spiral adjuster 8 is a product that meets the required precision and is vertically installed on one side of the probe detection unit 20. Fine-tuning is performed by the top knob. During fine-tuning, the operator can precisely control the distance between the probe detection unit 20 and the scraper chain 22 to be tested according to the detection requirements.

[0087] The host computer is used to receive the motional voltage and induced voltage generated by the detection coil 18 in the probe detection unit 20 based on the motional eddy current signal and the induced eddy current signal, and to calculate the running speed of the scraper chain 22 under test based on the motional voltage, and to calculate the tension on the scraper chain 22 under test based on the induced voltage.

[0088] In this embodiment, the probe detection unit 20 is placed inside the detection protection unit, the host computer is connected to the probe detection unit 20, and the detection lift-off control unit 21 is installed on one side of the detection protection unit.

[0089] In this embodiment of the invention, a dynamic characteristic eddy current detection system for a scraper chain is constructed. The probe detection unit 20 is installed in a suitable position, maintaining an appropriate distance from the scraper chain 22 under test. This distance is determined based on the detection range of the probe detection unit 20 and the operating conditions of the scraper chain 22 under test, and is generally between a few millimeters and tens of millimeters. Simultaneously, the drive circuit of the excitation coil 16 and the signal acquisition circuit of the detection coil 18 are connected, and connected to a host computer, ensuring that the circuit connections are correct.

[0090] This embodiment provides a method for detecting the dynamic characteristics of a scraper chain using eddy currents, which can be used in the aforementioned scraper chain dynamic characteristics eddy current detection system, such as... Figure 7 As shown, the process includes the following steps:

[0091] S1: The excitation coil 16 in the control probe detection unit 20 is supplied with an alternating current of preset parameters to generate an alternating magnetic field;

[0092] S2: Collect the motional voltage generated by the motional eddy current signal generated by the scraper chain 22 cutting magnetic field lines when it moves in the alternating magnetic field.

[0093] S3: Collect the induced eddy current signal generated by the change in magnetic permeability of the scraper chain 22 when it moves in the alternating magnetic field, and convert it into the induced voltage.

[0094] S4: Based on the dynamic voltage and induced voltage, and according to the preset speed-voltage relationship model and the preset tension-voltage relationship model, the real-time running speed and real-time tension of the scraper chain 22 under test during its movement are calculated.

[0095] Optionally, before step S1, the method further includes: determining the optimal lift-off distance between the probe detection unit 20 and the scraper chain 22 under test through COMSOL simulation; moving the probe detection unit 20 to a position close to the optimal lift-off distance through the coarse adjustment component of the detection lift-off control unit 21; and finally precisely adjusting the probe detection unit 20 to the optimal lift-off distance through the fine adjustment component.

[0096] In this embodiment, in the multiphysics simulation software COMSOL based on finite element analysis, the process of the scraper chain 22 cutting magnetic field lines is simulated by setting up a thin plate and a permanent magnet. Figure 8 The figure shows the total output voltage of detection coil 18. As the lift-off distance of the detection lift-off control unit 21 changes, the results in the figure show that when the lift-off distance increases, the total output voltage received by the detection coil 18 decreases. The trend is decreasing. The permanent magnet emits magnetic field lines, and the thin plate moves within the magnetic field, cutting through these lines and generating motional eddy currents within the plate. The corresponding magnetic field diagrams and eddy current diagrams at different velocities are shown in Figure 9- Figure 12 As shown, the results indicate that with the operating speed of the scraper chain 22 under test... Increase the dynamic eddy current in the scraper chain 22 under test. It will be enhanced.

[0097] Figure 13 It is motional voltage With the running speed of the scraper chain 22 under test The changing pattern of the scraper chain 22 under test, when the running speed When the voltage increases, the dynamic voltage is fed back to the detection coil 18. It shows an increasing trend, as shown in the figure. The figure shows the x-coordinate of the cutting point in the thin plate. This represents the ordinate of the cutting point in the thin plate.

[0098] Figure 14 What is shown is With the magnetic permeability of the scraper chain 22 to be tested The changing pattern of the magnetic permeability of the scraper chain 22 under test. When the voltage increases, the feedback voltage received by the detection coil 18 It also increases accordingly.

[0099] The above-mentioned patterns indicate that the eddy current detection method for the dynamic characteristics of the scraper chain provided in this application can simultaneously measure the tension and speed of the scraper chain 22 under test, which significantly improves the efficiency and accuracy of the dynamic characteristics detection of the scraper chain.

[0100] In this embodiment, the probe detection unit 20 can detect the speed and tension of the scraper chain, and use motional eddy currents to detect the running speed of the scraper chain 22 under test. Different speeds of the scraper chain 22 under test result in motional eddies generated on the scraper chain 22 under test. The difference lies in the dynamic voltage fed back to the detection coil 18. They are also different; the tension of the scraper chain 22 under test is detected by using induced eddy currents. When the scraper chain 22 under test moves in a magnetic field and cuts magnetic field lines, induced eddy currents are generated inside the scraper chain 22 under test. When the scraper chain 22 under test is subjected to tension, the magnetic permeability of the scraper chain 22 under test is... Changes will occur. The distribution of the magnetic field inside the material of the scraper chain 22 under test will change, and the intensity and distribution of the induced eddy currents will change accordingly. The change in the magnetic field generated by the induced eddy currents will ultimately affect the magnetic field fed back to the probe detection unit 20, thus affecting the feedback voltage fed back to the detection coil 18. Also different, the total output voltage of detection coil 18 for:

[0101]

[0102] In the formula, This represents the functional relationship between the running speed and magnetic permeability of the scraper chain 22 under test and the voltage conversion. This represents the set of feedback voltages for both motional and induced eddy currents.

[0103] Optionally, step S4 further includes: processing the dynamic voltage and induced voltage through a preset signal conditioning circuit, then inputting them into a data acquisition card to convert them into digital signals, and then calculating the real-time running speed and real-time tension of the scraper chain 22 under test during its movement according to a preset speed-voltage relationship model and a preset tension-voltage relationship model.

[0104] In this embodiment, when the scraper chain 22 under test is running, an alternating current is applied to the excitation coil 16, generating an alternating magnetic field. The scraper chain 22 under test moves in this magnetic field, and according to the principle of motional eddy currents, different running speeds of the scraper chain 22 under test... The corresponding dynamic eddy current generated below The difference lies in the motional voltage induced by the detection coil 18. The voltage signal from the detection coil 18 is collected, amplified, filtered, and processed by the signal conditioning circuit before being input into the data acquisition card. The data acquisition card converts the analog signal into a digital signal and transmits it to the computer for analysis and processing. Based on the preset speed-voltage relationship model, the speed of the scraper chain 22 under test is calculated.

[0105] In this embodiment, when the scraper chain 22 under test is subjected to tension, its magnetic permeability is... Changes occur, the internal magnetic field distribution changes, and induced eddy currents appear. Changes occur. The intensity and distribution of the induced eddy currents alter the magnetic field they generate, which in turn affects the feedback voltage induced by the detection coil 18. Similarly, signals are collected through detection coil 18, processed, and input into the computer. The tension on the scraper chain is calculated based on the preset tension-voltage relationship model.

[0106] In this embodiment, the preset velocity-voltage relationship model and the preset tension-voltage relationship model are hybrid models constructed based on two-dimensional finite element models and three-dimensional finite element models. In this hybrid model, the material and magnetic field corresponding to the scraper chain 22 under test are set, and the hybrid model is meshed. At the same time, the relevant parameters are adjusted according to the actual research needs to obtain the corresponding preset velocity-voltage relationship model and preset tension-voltage relationship model. Finally, after running and obtaining the results, the real-time running speed and real-time tension of the scraper chain 22 under test during its movement are calculated.

[0107] An optional embodiment of the present invention provides a computer device comprising: one or more processors, memory, and interfaces for connecting the components, including high-speed interfaces and low-speed interfaces. The components are interconnected via different buses and can be mounted on a common motherboard or otherwise installed as needed. The processor can process instructions executed within the computer device, including instructions stored in or on memory for displaying graphical information on external input / output devices (such as display devices coupled to the interface). In some optional embodiments, multiple processors and / or multiple buses can be used with multiple memories and multiple memory modules, if desired. Similarly, multiple computer devices can be connected, each providing some of the necessary operations (e.g., as a server array, a group of blade servers, or a multiprocessor system).

[0108] The processor can be a central processing unit, a network processor, or a combination thereof. The processor may further include hardware chips. These hardware chips can be application-specific integrated circuits (ASICs), programmable logic devices (PLDs), or combinations thereof. The programmable logic devices can be complex programmable logic devices (CLPs), field-programmable gate arrays (FPGAs), general-purpose array logic devices (GDAs), or any combination thereof.

[0109] The memory stores instructions executable by at least one processor to cause the at least one processor to perform the method shown in the above embodiments.

[0110] The memory may include a stored program area and a stored data area, wherein the stored program area may store the operating system and application programs required for at least one function; the stored data area may store data created based on the use of the computer device, etc. Furthermore, the memory may include high-speed random access memory and may also include non-transitory memory, such as at least one disk storage device, flash memory device, or other non-transitory solid-state storage device. In some alternative embodiments, the memory may optionally include memory remotely located relative to the processor, which can be connected to the computer device via a network. Examples of such networks include, but are not limited to, the Internet, intranets, local area networks, mobile communication networks, and combinations thereof.

[0111] The memory may include volatile memory, such as random access memory; the memory may also include non-volatile memory, such as flash memory, hard disk or solid-state drive; the memory may also include a combination of the above types of memory.

[0112] The computer device also includes a communication interface for communicating with other devices or communication networks.

[0113] This invention also provides a computer-readable storage medium. The methods described above according to embodiments of the invention can be implemented in hardware or firmware, or implemented as computer code that can be recorded on a storage medium, or implemented as computer code downloaded over a network and originally stored on a remote storage medium or a non-transitory machine-readable storage medium and then stored on a local storage medium. Thus, the methods described herein can be processed by software stored on a storage medium using a general-purpose computer, a dedicated processor, or programmable or dedicated hardware. The storage medium can be a magnetic disk, optical disk, read-only memory, random access memory, flash memory, hard disk, or solid-state drive, etc.; further, the storage medium can also include combinations of the above types of memory. It is understood that computers, processors, microprocessor controllers, or programmable hardware include storage components capable of storing or receiving software or computer code, which, when accessed and executed by the computer, processor, or hardware, implements the methods shown in the above embodiments.

[0114] Although embodiments of the invention have been described in conjunction with the accompanying drawings, those skilled in the art can make various modifications and variations without departing from the spirit and scope of the invention, and all such modifications and variations fall within the scope defined by the appended claims.

Claims

1. A scraper chain dynamic characteristic eddy current detection system, characterized in that, include: The system includes a probe detection unit (20), a detection protection unit, a detection lift-off control unit (21), and a host computer. The probe detection unit (20) includes an excitation coil (16), a detection coil (18), and an iron core (17). The excitation coil (16) and the detection coil (18) are arranged in an array, with the excitation coil (16) on the inner side and the detection coil (18) on the outer side. Both the excitation coil (16) and the detection coil (18) are array structures composed of multiple independent coil units. The iron core (17) is vertically arranged at the center of the excitation coil (16). The coil units of each excitation coil (16) are connected in series to generate an alternating magnetic field. The coil units of each detection coil (18) are connected in parallel to simultaneously sense the motional eddy current signal determined by the speed of the scraper chain (22) under test, and the induced eddy current signal caused by the change in the permeability of the scraper chain (22) under test due to the change in the tension of the scraper chain (22). The detection protection unit is used to accommodate and protect the probe detection unit (20), and is provided with an openable and closable maintenance port; The detection lifting control unit (21) includes a coarse adjustment component and a fine adjustment component for controlling the distance between the probe detection unit (20) and the scraper chain (22) to be tested. The coarse adjustment component is used to realize a large range of adjustment of the distance between the probe detection unit (20) and the scraper chain (22) to be tested, and the fine adjustment component is used to realize a small adjustment of the distance between the probe detection unit (20) and the scraper chain (22) to be tested. The host computer is used to receive the motional voltage and induced voltage generated by the detection coil (18) in the probe detection unit (20) based on the motional eddy current signal and the induced eddy current signal, and calculate the running speed of the scraper chain (22) under test based on the motional voltage, and calculate the tension on the scraper chain (22) under test based on the induced voltage.

2. The eddy current detection system for the dynamic characteristics of a scraper chain according to claim 1, characterized in that, The detection and protection unit includes a first housing (24), a first drive motor (15), a first reel (23), a first gear (14), a chain (13), a membrane (19), and a traction rope; The first housing (24) is provided with an openable and closable inspection port at both the upper and lower parts, and an inspection component for sealing the inspection port is installed at each inspection port. Two first spools (23) are provided and are positioned opposite each other at the lower inspection port of the first housing (24) for winding a film (19) to seal or open the inspection port; the first drive motor (15) is mounted on the first housing (24) for driving one of the first spools (23) to rotate. Both of the first spools (23) are fixedly connected to the first gears (14), and the two first gears (14) are driven by the chain (13); one end of the film (19) is fixed to the first spool (23) connected to the first drive motor (15), and the other end of the film (19) is fixedly connected to the traction rope wound with the other first spool (23). The first drive motor (15) drives the first spool (23) to rotate forward or backward, and drives the other first spool (23) to rotate synchronously through the first gear (14) and the chain (13), thereby driving the film (19) to move in the film channel on the inner surface of the first housing (24), so as to realize the unfolding or rolling up of the film (19); When the film (19) is in the rolled-up state, the film (19) is wound on the first spool (23) connected to the first drive motor (15), and the other end of the film (19) is embedded in the film channel on the inner surface of the first housing (24), and the traction rope is located in the film channel; When the film (19) is in the unfolded state, the other end of the film (19) passes through the film channel on the inner surface of the first housing (24) and is wrapped around another first spool (23).

3. The eddy current detection system for the dynamic characteristics of a scraper chain according to claim 2, characterized in that, The maintenance assembly of the maintenance port at the upper part of the first housing (24) includes an upper door panel (1) hinged to the upper edge of the maintenance port, and a lower door panel (2) slidably connected to the lower end of the upper door panel (1); a handle (3) is fixed on the side of the lower door panel (2) away from the upper door panel (1), and sliding blocks (11) are fixedly connected to both sides of the lower door panel (2). A horizontally arranged sliding groove is opened on the side wall of the lower door panel (2) away from the detection and protection unit, and the sliding block (11) is slidably connected to the sliding groove.

4. The eddy current detection system for the dynamic characteristics of a scraper chain according to claim 3, characterized in that, A spring (12) is provided in the sliding groove. One end of the spring (12) is fixedly connected to the inner wall of the sliding groove, and the other end is fixedly connected to a baffle (10). The baffle (10) is connected to the sliding block (11). The spring (12) is used to push the sliding block (11) against the inner wall of the detection protection unit through the baffle (10).

5. The eddy current detection system for the dynamic characteristics of a scraper chain according to claim 1, characterized in that, The coarse adjustment component in the detection lift-off control unit (21) includes: a second drive motor (7), a second reel (6), a second gear (5), and a rack (4). The output shaft of the second drive motor (7) is connected to the second reel (6) via a coupling; The second gear (5) is fixedly installed in the middle of the second spool (6) and rotates synchronously with the second spool (6); The rack (4) is connected to the first housing (24) of the detection protection unit and is located on one side of the second gear (5) and meshes with the second gear (5). When the second gear (5) rotates, it drives the rack (4) to make linear motion, thereby driving the probe detection unit (20) to move to perform the initial adjustment of the distance between the probe detection unit (20) and the scraper chain (22) to be tested.

6. The eddy current detection system for the dynamic characteristics of a scraper chain according to claim 5, characterized in that, The detection lift-off control unit (21) also includes a second housing; The rack (4) is bolted to the second housing.

7. The eddy current detection system for the dynamic characteristics of a scraper chain according to claim 6, characterized in that, The fine-tuning components in the detection lift-off control unit (21) include: a horizontal plate (9), a spiral adjuster (8), and a fastening bolt (25). The screw pitch adjuster (8) includes a top knob, an internal screw, an internal nut, a moving block, a guide rod, a hollow guide post and a housing. The internal screw is threadedly connected to the internal nut. The moving block is fixedly connected to one side of the internal nut and a groove is provided on the housing corresponding to the position of the moving block. The other end of the moving block is fixedly connected to the first housing (24). The upper end of the guide rod is fixedly connected to the lower end of the outer shell, and the lower end of the guide rod is slidably connected to the hollow guide column. The hollow guide column is fixedly connected to the horizontal plate (9) through a connecting block. The side wall of the hollow guide column is provided with a threaded hole. After the initial adjustment is completed, the guide rod can be fixed by the fastening bolt (25) threadedly connected to the threaded hole. When the top knob is adjusted, the internal screw rotates, causing the internal nut and the moving block to move up and down, which in turn causes the first housing (24) connected to the moving block to move up and down, thereby realizing the secondary adjustment control of the distance between the probe detection unit (20) and the scraper chain (22) to be tested; The horizontal plate (9) is fixedly connected to the second housing, and the horizontal plate (9) is located below the probe detection unit (20).

8. A method for detecting the dynamic characteristics of a scraper chain using eddy currents, applicable to the eddy current detection system for the dynamic characteristics of a scraper chain as described in any one of claims 1-7, characterized in that, Includes the following steps: S1: The excitation coil (16) in the control probe detection unit (20) is supplied with an alternating current of preset parameters to generate an alternating magnetic field; S2: Collect the motion voltage generated by the motional eddy current signal generated by the scraper chain (22) cutting magnetic field lines when it moves in the alternating magnetic field. S3: Collect the induced eddy current signal generated by the change in magnetic permeability of the scraper chain (22) when it moves in the alternating magnetic field and convert it into the induced voltage. S4: Based on the dynamic voltage and induced voltage, and according to the preset speed-voltage relationship model and the preset tension-voltage relationship model, the real-time running speed and real-time tension of the scraper chain (22) under test during the motion process are calculated.

9. The method for detecting the dynamic characteristics of a scraper chain using eddy currents according to claim 8, characterized in that, Before step S1, the following is also included: The optimal lift-off distance between the probe detection unit (20) and the scraper chain (22) under test is determined by COMSOL simulation. Then, the probe detection unit (20) is moved to a position close to the optimal lift-off distance by the coarse adjustment component of the detection lift-off control unit (21). Finally, the probe detection unit (20) is precisely adjusted to the optimal lift-off distance by the fine adjustment component.

10. The method for detecting the dynamic characteristics of a scraper chain using eddy currents according to claim 8, characterized in that, Step S4 also includes: The dynamic voltage and induced voltage are processed by a preset signal conditioning circuit, then input into a data acquisition card and converted into digital signals. Then, based on the preset speed-voltage relationship model and the preset tension-voltage relationship model, the real-time running speed and real-time tension of the scraper chain (22) under test during its movement are calculated.

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