Device for observing dynamic settlement of overlying basic roof rock stratum in mine goaf

Abstract

The invention relates to the technical field of mining pressure observation, and discloses a device for observing the dynamic settlement of a basic roof rock stratum overlying a mine goaf, which comprises a light source, a light receiving component and a plurality of optical fibers, and further comprises a pipe body, a spiral opening is formed in the pipe wall of the pipe body, so that a hollow spiral part is formed in the pipe wall; when the pipe body is fixed in the monitoring hole, the screw pitch of the spiral part can be changed when the rock stratum settles, so that the plurality of optical fibers fixed in the pipe body are driven to be stretched or compressed, and the settlement displacement of the rock stratum is reflected by utilizing the wavelength offset in the optical fibers. According to the technical scheme, the multiple optical fibers are arranged on the pipe body with the high deformation capacity, the settlement amount of the rock stratum can be monitored in multiple directions, sufficient friction force is achieved so that the pipe body can transmit deformation force to the optical fibers, the structure of the auxiliary optical fibers can be changed, and the settlement amount of the rock stratum can be monitored; therefore, the accuracy of real-time dynamic monitoring of the settlement amount of the rock stratum can be improved.

Description

Technical Field

[0001] This invention relates to the field of mining pressure monitoring technology, specifically to a device for monitoring the dynamic settlement of the overlying basic roof strata in a mine goaf. Background Technology

[0002] The existence of mine pressure manifests itself through a series of phenomena, collectively known as mine pressure manifestations. These include roof subsidence and floor bulging, support deformation and failure, rock strata movement and collapse, direct roof collapse as the working face advances, periodic fractures and subsidence of the basic roof, and even impacts the surface to form subsidence zones, coal wall spalling, rock bursts, and gas outbursts. In actual mining activities, there are one or several thick and hard key rock strata in the overlying strata of the coal seam. These strata control the movement of all or part of the overlying strata and play a decisive role in mine pressure manifestations, fracture development, and surface subsidence. After the coal seam is mined, the weight of the overlying strata is transferred to the coal body on both sides and in front of the goaf, forming a concentrated stress much higher than the original rock stress. This stress-increased area is called the "support pressure zone," and the support pressure is the main cause of coal wall spalling, rock bursts, and difficulty in maintaining roadways. As the working face advances, the supporting pressure of the overlying strata in the goaf gradually increases. Therefore, in order to ensure the safety and stability of the mining space, it is necessary not only to proactively address the supporting pressure during mining, but also to use sensors to monitor the stress changes and settlement of the strata in concentrated stress areas in real time. For example, technologies such as micro-vibration, online stress monitoring, and fiber optic sensing can be used to monitor the mine pressure manifestation in real time, and early warning and intelligent support can be achieved based on big data and artificial intelligence.

[0003] Currently, fiber optic sensors can be assembled into gratings for large-scale monitoring, and are therefore often used to observe the dynamic settlement of the overlying roof strata in goaf areas. However, although the detection range is wide, the traditional fiber optic sensor deployment method makes it difficult to form sufficient friction with the borehole wall in the monitoring deep hole. As a result, when settlement occurs, the spiral fiber will slip due to the elastic force of the fiber itself, reducing the accuracy of the detection. Summary of the Invention

[0004] Technical problems to be solved To address the shortcomings of existing technologies, this invention provides a device for observing the dynamic settlement of the overlying basic roof strata in a mining goaf. This device solves the problem that traditional fiber optic sensors, when deployed in deep boreholes, cannot generate sufficient friction with the borehole wall, leading to slippage of the spiral fiber due to its own elasticity when settlement occurs, thus reducing the accuracy of the detection.

[0005] Technical solution To achieve the above objectives, the present invention provides the following technical solution: a device for observing the dynamic settlement of the overlying basic roof strata in a mining goaf, comprising a light source, a light-receiving component, and multiple optical fibers, and further comprising: The tube body has a spiral opening on its wall to form a hollow spiral section. When fixed in the monitoring hole, the spiral section can generate a change in pitch when the rock strata settle, thereby causing multiple optical fibers fixed inside the tube body to be stretched or compressed. The wavelength shift in the optical fibers is used to reflect the settlement displacement of the rock strata. The sleeve has a transmission mechanism installed inside. The transmission mechanism uses a central shaft to rotate and change the diameter of the tube. After the tube enters the monitoring hole, it returns to its original diameter under its own elasticity. This allows the tube to be interference-fitted into the monitoring hole to form a spiral energy-absorbing part, thereby changing the initial structure of the auxiliary optical fiber for monitoring the settlement of the rock layer. A pre-fixing component, controlled by a transmission mechanism, is capable of pre-fixing the tube body when the tube diameter is reset; A lateral monitoring component is installed inside the pipe along with an optical fiber. One end of the lateral monitoring component contacts the central axis to support the pipe, and a displacement sensor can be used to monitor the lateral displacement of the rock strata.

[0006] As a further description of the above technical solution, all of the optical fibers are U-shaped, with one end connected to a light source and the other end connected to a light-receiving component. Multiple arc-shaped sections are respectively provided on the two vertical sections of the optical fibers, and a straight mounting section is formed between two adjacent arc-shaped sections. When the spiral section on the tube is stretched or compressed, the arc-shaped section deforms, so that the wavelength shift in the optical fiber reflects the settlement displacement of the rock layer. The openings of the arc-shaped sections on the multiple optical fibers all face the spiral groove, so that the openings of the arc-shaped sections on the optical fibers are distributed in a spiral path.

[0007] As a further description of the above technical solution, a spiral groove is provided on the inner side of the tube body on the spiral part, and a spiral fiber core is installed in the spiral groove. The spiral fiber core can deform with the change of the spiral part, so that the wavelength shift in the optical fiber reflects the settlement displacement of the rock layer.

[0008] As a further description of the above technical solution, the transmission mechanism includes a central shaft and a sleeve. The lower end of the sleeve is provided with a flared part, which is inserted into the upper end of the tube body and fixedly connected by bolts. Two circular plates are fixedly connected inside the sleeve. The center of the lower circular plate is rotatably connected to the shaft wall of the central shaft through a sealed bearing. A worm gear is fixedly connected to the shaft wall of the central shaft. A worm is meshed on one side of the worm gear. A motor is fixedly connected to the lower circular plate. The output end of the motor is fixedly connected to one end of the worm. Two perforated rubber blocks are fixedly connected between the upper and lower circular plates. The lower end of the tube is fixedly connected to a ring, and a connecting component connected to the central shaft is installed inside the ring. The connecting component causes the spiral part installed on the tube to deform and reduce its diameter through the torque transmitted by the central shaft. At the same time, the reverse rotation of the transmission mechanism can also apply a certain torque to the tube, so that the tube can be stably installed in the monitoring hole.

[0009] As a further description of the above technical solution, the connecting assembly includes an annular plate and a base plate, both of which are fixed inside a ring. A plurality of rectangular blocks are fixedly connected between the annular plate and the base plate. The lower end of the central shaft is rotatably connected to the base plate through a sealed bearing. A plurality of brake rods are fixedly connected to the shaft wall of the central shaft. One end of each of the brake rods extends between the annular plate and the base plate and is located on one side of the rectangular block.

[0010] As a further description of the above technical solution, a connecting ring is installed at the upper end of the sleeve, the outer diameter of the connecting ring matches the inner diameter of the ring, and a fixing bolt connected to the connecting ring is sleeved on the side wall of the ring through a circular hole.

[0011] As a further description of the above technical solution, the pre-fixed assembly includes multiple rectangular tubes. Multiple rectangular tubes are fixedly installed on the tube wall of the sleeve through multiple rectangular openings, and one end of the rectangular tubes is a sealed structure. Fixing blocks are slidably sleeved inside each of the multiple rectangular tubes. Two guide rods are sleeved on one side of the fixing block through blind holes, and one end of the guide rod is fixed to one side of the rectangular tube. A spring is sleeved on the rod wall of the guide rod. The spring is set between the fixing block and one side of the sealed end of the rectangular tube. When the pull rope is released, the elastic force of the spring pushes the fixing block to contact the inside of the monitoring hole. A pull rope is fixedly connected to one side of the fixing block. A winding reel is fixedly connected to the shaft wall of the central shaft. One end of the pull rope passes through the rectangular tube and is fixed to the winding reel.

[0012] As a further description of the above technical solution, the side wall of the pull rope is fitted with a plastic bushing, the plastic bushing is fixed at the center of one side of the rectangular tube, and the edge of the reel is provided with an anti-detachment curling edge.

[0013] As a further description of the above technical solution, the transverse monitoring component includes a transverse tube, which is a rectangular structure with a fixed base fixedly connected to one end. The fixed base is provided with a retaining seat, and the retaining seat is provided with a fixing part matching the diameter of the optical fiber. The fixed base and the retaining seat are fixed to the inner wall of the tube by bolts. A linear displacement sensor is fixedly connected inside the transverse tube. A slider is fixedly connected to one end of the measuring rod of the linear displacement sensor. One end of the slider extends to the transverse side and contacts the shaft wall of the central axis through a set arc groove. A return spring is provided on the rod wall of the measuring rod of the linear displacement sensor.

[0014] As a further description of the above technical solution, the side wall of the tube body is fixedly connected with multiple conical blocks. The conical blocks are installed on the spiral part and distributed in a spiral route. The multiple conical blocks are distributed circumferentially relative to the tube body to form a conical fixing part, and the diameter of the conical fixing part is larger than the diameter of the tube body.

[0015] Beneficial effects Compared with the prior art, the present invention provides a device for observing the dynamic settlement of the overlying basic roof strata in a mining goaf, which has the following beneficial effects: 1. This technical solution designs a tube body capable of deformation and installs multiple optical fibers arranged in a ring inside the tube body. The optical fibers are equipped with arc-shaped sections that are sensitive to deformation. The arc-shaped sections can be used to promptly and effectively reflect the settlement of the rock strata in the monitoring hole. Moreover, the observation device designed in this technical solution can utilize the freely combined length of the tube body, or multiple units can be arranged at intervals in a monitoring hole to realize the observation of the dynamic settlement of the overlying roof rock strata in the goaf of the mine.

[0016] 2. Unlike traditional methods that directly coil the fiber core inside the monitoring hole, where insufficient friction between the hole sidewall and the fiber core prevents deformation and affects light refraction, leading to inaccurate monitoring, this method employs multiple optical fibers arranged on a highly deformable tube. This allows for monitoring of rock subsidence in multiple directions. The tube fits snugly inside the monitoring hole and provides sufficient friction to transfer deformation force to the optical fibers, altering the initial structure of the auxiliary optical fibers to monitor rock subsidence. This improves the accuracy of real-time dynamic monitoring of rock subsidence.

[0017] 3. In actual monitoring, lateral displacement can also occur during rock strata fracturing. Therefore, this technical solution designs a linear sensor that can monitor lateral displacement. The measuring rod of the linear sensor receives the lateral force on the pipe body and is supported by the central axis. When lateral displacement occurs, the linear displacement sensor can generate an electrical signal in a timely manner and transmit it to the ground receiving device. The optical fiber and spiral fiber core installed in the pipe body can also generate corresponding changes in the monitoring optical signal. At this time, the changes in the monitoring optical signal and the signal fluctuations of the linear displacement sensor occur simultaneously. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the structure of a device for observing the dynamic settlement of the overlying basic roof strata in a mining goaf, as proposed in this invention. Figure 2 This is a schematic diagram of the tube structure in a device for observing the dynamic settlement of the overlying basic roof strata in a mining goaf, as proposed in this invention. Figure 3This is a schematic diagram of the tube body and spiral fiber core in a device for observing the dynamic settlement of the overlying basic roof strata in a mining goaf area, as proposed in this invention. Figure 4 This is a schematic diagram of the optical fiber and central axis in a device for observing the dynamic settlement of the overlying basic roof strata in a mining goaf area, as proposed in this invention. Figure 5 This is a schematic diagram of the optical fiber structure in a device for observing the dynamic settlement of the overlying basic roof strata in a mining goaf area, as proposed in this invention. Figure 6 This is a diagram showing the arrangement of multiple arc-shaped sections on an optical fiber in a monitoring device for the dynamic settlement of the overlying basic roof strata in a mining goaf area, as proposed in this invention. Figure 7 This is a schematic diagram of the central axis and multiple transverse monitoring components in a monitoring device for dynamic settlement of the overlying basic roof strata in a mining goaf area proposed in this invention. Figure 8 This is a schematic diagram of the internal transmission mechanism in the casing of a device for monitoring the dynamic settlement of the overlying basic roof strata in a mining goaf, as proposed in this invention. Figure 1 ; Figure 9 This is a schematic diagram of the internal transmission mechanism in the casing of a device for monitoring the dynamic settlement of the overlying basic roof strata in a mining goaf, as proposed in this invention. Figure 1 ; Figure 10 This is a schematic diagram of the inner ring connecting component in a device for observing the dynamic settlement of the overlying basic roof strata in a mining goaf area, as proposed in this invention. Figure 11 This is a schematic diagram of the tube body, central axis, transverse monitoring components, and optical fiber in a monitoring device for dynamic settlement of the overlying basic roof strata in a mining goaf area proposed in this invention.

[0019] In the diagram: 1. Sleeve; 2. Tube body; 3. Conical block; 4. Spiral opening; 5. Ring; 6. Arc-shaped part; 7. Spiral part; 8. Fixing block; 9. Connecting ring; 10. Flared part; 11. Spiral fiber core; 12. Linear mounting part; 13. Optical fiber; 14. Slider; 15. Return spring; 16. Linear displacement sensor; 17. Arc-shaped groove; 18. Horizontal tube; 19. Fixing seat; 20. Central shaft; 21. Rubber block; 22. Motor; 23. Circular plate; 24. Worm gear; 25. Worm wheel; 26. Rectangular tube; 27. Spring; 28. Guide rod; 29. ​​Pull rope; 30. Reel; 31. Annular plate; 32. Rectangular block; 33. Brake rod; 34. Base plate. Detailed Implementation

[0020] 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, and 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.

[0021] Example: See attached document Figure 1-11 This technical solution designs a deformable tube 2 and installs multiple ring-shaped optical fibers 13 inside the tube 2. Each optical fiber 13 has an arc-shaped section 6 that is sensitive to deformation. The arc-shaped section 6 can effectively and promptly reflect the settlement of the rock strata within the monitoring hole. Furthermore, the observation device designed in this technical solution can utilize the freely combined lengths of the tube 2, or multiple units can be arranged at intervals within a single monitoring hole. This allows for the observation of the dynamic settlement of the overlying roof strata in the goaf of a mine. The observation device provided by this technical solution includes a light source, a light-receiving component, and multiple optical fibers 13. Figure 4 The diagram shows the use of three optical fibers 13. The specific technical solution also includes a tube body 2. The tube body 2 has a spiral opening 4 on its wall to form a hollow spiral part 7. When fixed in the monitoring hole, the spiral part 7 can generate a change in pitch when the rock layer settles, thereby causing multiple optical fibers 13 fixed inside the tube body 2 to be stretched or compressed. The wavelength shift in the optical fiber 13 reflects the settlement displacement of the rock layer. Since this technical solution adopts a spiral structure design for the tube body 2, and the observation hole is designed according to the rock layer thickness and observation location, the diameter of the tube body 2 needs to be reserved for installation during the design. For example, for a monitoring hole diameter of 150mm, the diameter of the tube body 2 is selected to be 140mm-145mm. It is also equipped with a sleeve 1 installed on the upper end of the tube body 2. A transmission mechanism is installed inside the sleeve 1. The transmission mechanism uses the central shaft 20 to rotate and change the diameter of the tube body 2. After the tube body 2 enters the monitoring hole, it returns to its original diameter under its own elasticity. This allows the tube body 2 to be interference-fitted into the monitoring hole to form a spiral energy-absorbing part, thereby changing the initial structure of the auxiliary optical fiber 13 for monitoring the settlement of the rock layer. Meanwhile, a pre-fixing component is also provided inside the sleeve 1. The pre-fixing component is controlled by the transmission mechanism and can pre-fix the tube body 2 when the diameter of the tube body 2 is reset. In order to monitor the possible lateral displacement of the rock strata, this technical solution also designs a lateral monitoring component. The lateral monitoring component and the optical fiber 13 are installed together in the tube body 2. One end of the lateral monitoring component can be in contact with the central shaft 20 to support the tube body 2. At the same time, the configured displacement sensor can be used to monitor the amount of lateral displacement of the rock strata.

[0022] Unlike traditional methods that directly coil the optical fiber core inside the monitoring hole, where insufficient friction between the hole sidewall and the fiber core prevents deformation and affects light refraction, leading to inaccurate monitoring, this method employs multiple optical fibers 13 arranged on a tube 2 with high deformation capacity. This allows for monitoring of rock subsidence in multiple directions. Furthermore, the tube 2 fits snugly inside the monitoring hole and provides sufficient friction to transfer deformation force to the optical fibers 13, thus altering the initial structure of the auxiliary optical fibers 13 to monitor rock subsidence. This improves the real-time dynamic monitoring of rock subsidence.

[0023] Specifically, multiple optical fibers 13 are U-shaped, with one end connected to a light source and the other end connected to a light-receiving component. Multiple arc-shaped sections 6 are respectively set on the two vertical sections of the optical fiber 13, and a straight mounting section 12 is formed between two adjacent arc-shaped sections 6. When the spiral section 7 on the tube body 2 is stretched or compressed, the arc-shaped section 6 deforms, so that the wavelength shift in the optical fiber 13 reflects the settlement displacement of the rock layer. The openings of the arc-shaped sections 6 on the multiple optical fibers 13 all face the spiral groove, so that the openings of the arc-shaped sections 6 on the optical fiber 13 are distributed in a spiral path.

[0024] like Figure 6 As shown, the arc centers of multiple arc-shaped portions 6 on multiple optical fibers 13 are distributed in a spiral path (as shown by the dashed line in the figure), and the length of the arc center of the arc portion 6 is twice that of the opening.

[0025] In addition, this technical solution also provides a spiral groove on the inner side of the tube body 2 located on the spiral part 7, and a spiral fiber core 11 is installed in the spiral groove. The spiral fiber core 11 can deform with the change of the spiral part 7, so that the wavelength shift in the optical fiber 13 reflects the settlement displacement of the rock layer.

[0026] The helical lengths of the helical section 7 and the helical core 11 are calculated using the following formula;

[0027] Total length (N laps):

[0028] Simplified formula:

[0029] Where P is the pitch; H is the drilling depth; D is the drilling diameter; and r is the helix radius. .

[0030] For general monitoring of goaf areas, the pitch P is between 0.1 and 0.4 m.

[0031] Key areas for delamination: pitch P is 0.05-0.15m (adjusted according to borehole diameter).

[0032] Specifically, the transmission mechanism designed in this technical solution includes a central shaft 20 and a sleeve 1. The lower end of the sleeve 1 is provided with a flared part 10, which is inserted into the upper end of the tube body 2 and fixedly connected by bolts. Two circular plates 23 are fixedly connected inside the sleeve 1. The center of the lower circular plate 23 is rotatably connected to the shaft wall of the central shaft 20 through a sealed bearing. A worm gear 25 is fixedly connected to the shaft wall of the central shaft 20. A worm 24 is meshed on one side of the worm gear 25. A motor 22 is fixedly connected to the lower circular plate 23. The output end of the motor 22 is fixedly connected to one end of the worm 24. Two perforated rubber blocks 21 are fixedly connected between the upper circular plate 23 and the lower circular plate 23. Multiple conical blocks 3 are fixedly connected to the side wall of the tube body 2. The conical blocks are installed on the spiral part 7 and distributed in a spiral route. The multiple conical blocks 3 are distributed circumferentially relative to the tube body 2 to form a conical fixing part, and the diameter of the conical fixing part is larger than the diameter of the tube body 2. A ring 5 is fixedly connected to the lower end of the tube body 2. A connecting assembly connected to the central shaft 20 is installed inside the ring 5. The torque transmitted by the connecting assembly through the central shaft 20 causes the spiral part 7 installed on the tube body 2 to deform and reduce its diameter. At the same time, the reverse rotation of the transmission mechanism can also apply a certain torque to the tube body 2, so that the tube body 2 can be stably installed in the monitoring hole. The connecting assembly includes an annular plate 31 and a base plate 34. Both the annular plate 31 and the base plate 34 are fixed inside the ring 5. Multiple rectangular blocks 32 are fixedly connected between the annular plate 31 and the base plate 34. The lower end of the central shaft 20 is rotatably connected to the base plate 34 through a sealed bearing. Multiple brake rods 33 are fixedly connected to the shaft wall of the central shaft 20. One end of each brake rod 33 extends between the annular plate 31 and the base plate 34 and is located on one side of the rectangular block 32.

[0033] Through the above scheme, the rotation of motor 22 drives worm gear 24 to rotate worm wheel 25. When worm wheel 25 rotates, it drives the central shaft to rotate. When the central shaft 20 rotates, it drives brake lever 33 to contact rectangular block 32. At this time, rectangular block 32 is subjected to force, which drives ring 5 to rotate. When ring 5 rotates, it drives tube body 2 to rotate. At this time, the upper part of tube body 2 is fixed, thus causing tube body 2 to twist, reducing the diameter of tube body 2. This makes the diameter of the conical fixing part composed of multiple conical blocks 3 smaller than the diameter of tube body 2, allowing the equipment to smoothly enter the monitoring hole. When the motor... When the tube 22 is flipped, under its own elastic force, the tube 2 returns to its original diameter. At this time, the conical block 3 first contacts the hole wall, so that the tube 2 and the monitoring hole can form a multi-point connection, so that the friction force can be maximized. In this way, when the rock strata undergo subsidence and fracture, the arc-shaped part 6 facing the spiral opening 4 can deform in time. At the same time, when the tube 2 is stretched or compressed, the spiral fiber core 11 embedded in it will also deform. In this way, the changes in the monitoring optical signal in the optical fiber (such as light intensity, wavelength, phase or scattering characteristics) can be used to determine whether a crack has appeared.

[0034] A connecting ring 9 is installed at the upper end of the sleeve 1. The outer diameter of the connecting ring 9 matches the inner diameter of the ring 5. The side wall of the ring 5 is fitted with a fixing bolt connected to the connecting ring 9 through a round hole. When the monitoring hole is deep, the connecting ring 9 and the ring 5 can be used to assemble the observation device, so that the length of the observation device can be adjusted according to the requirements.

[0035] Since this technical solution requires shrinking the tube body 2 and changing its diameter, a pre-fixing assembly is needed to initially fix the tube body 2 of the observation device by increasing friction. Specifically, the pre-fixing assembly includes multiple rectangular tubes 26. Multiple rectangular tubes 26 are fixedly installed on the wall of the sleeve 1 through multiple rectangular openings, and one end of each rectangular tube 26 is sealed. Fixing blocks 8 are slidably fitted inside each rectangular tube 26. Two guide rods 28 are fitted onto one side of each fixing block 8 through blind holes, and one end of each guide rod 28 is fixed to one side of the rectangular tube 26. A spring 27 is fitted onto the wall. The spring 27 is positioned between the fixed block 8 and one side of the sealed end of the rectangular tube 26. When the pull rope 29 is released, the elastic force of the spring 27 pushes the fixed block 8 to contact the inner side of the monitoring hole. A pull rope 29 is fixedly connected to one side of the fixed block 8. A take-up reel 30 is fixedly connected to the shaft wall of the central shaft 20. One end of the pull rope 29 passes through the rectangular tube 26 and is fixed to the take-up reel 30. A plastic bushing is fitted onto the side wall of the pull rope 29. The plastic bushing is fixed at the center of one side of the rectangular tube 26. An anti-detachment edge is provided at the edge of the reel 30.

[0036] When the central shaft 20 rotates, it synchronously drives the take-up reel 30 to rotate. The rotation of the take-up reel 30 causes the pull rope 29 to contract or release (according to the forward and reverse rotation of the central shaft 20). When the central shaft 20 rotates clockwise, the take-up reel 30 winds up the pull rope 29. At this time, the fixing block 8 is pulled back into the rectangular tube 26. When the tube body 2 reaches the preset position in the monitoring hole, the central shaft 20 is driven by the motor 22 to rotate. At the same time as releasing the pull rope 29, the wound tube body 2 is released. The fixing block 8 first contacts the hole wall under the push of the spring 27. Then the conical block 3 on the tube body 2 contacts the hole wall. At this time, the conical block 3 contacts the hole wall with a small contact area under the elastic force of the tube body 2. In this way, the tube body 2 with the optical fiber 13 can be tightly installed in the monitoring hole.

[0037] The lateral monitoring component includes a horizontal tube 18, which is rectangular in structure and has a fixed base 19 fixedly connected to one end. The fixed base 19 is provided with a retaining seat, and the retaining seat is provided with a fixing part that matches the diameter of the optical fiber 13. The fixed base 19 and the retaining seat are fixed to the inner wall of the tube body 2 by bolts. A linear displacement sensor 16 is fixedly connected inside the horizontal tube 18. A slider 14 is fixedly connected to one end of the measuring rod of the linear displacement sensor 16. One end of the slider 14 extends to the outside and contacts the shaft wall of the central shaft 20 through the provided arc-shaped groove 17. A return spring 15 is provided on the rod wall of the linear displacement sensor.

[0038] In actual monitoring, lateral displacement also occurs during rock fracture. Therefore, in this technical solution, a linear sensor 16 is designed to monitor lateral displacement. The measuring rod of the linear sensor 16 receives the lateral force of the tube body 2 and is supported by the central shaft 20. When lateral displacement occurs, the linear displacement sensor 16 can generate an electrical signal in a timely manner and transmit it to the ground receiving device. The optical fiber 13 and the spiral fiber core 11 installed in the tube body 2 can also generate corresponding changes in the monitoring optical signal. At this time, the changes in the monitoring optical signal and the signal fluctuations of the linear displacement sensor 16 occur simultaneously.

[0039] It should be noted that the term "comprising" or any other variation thereof is intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0040] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A device for observing the dynamic settlement of the overlying basic roof strata in a mining goaf, comprising a light source, a light-receiving component, and multiple optical fibers (13), characterized in that, Also includes: The pipe body (2) has a spiral opening (4) on its wall to form a hollow spiral part (7). When fixed in the monitoring hole, the spiral part (7) can generate a change in pitch when the rock layer settles, thereby driving multiple optical fibers (13) fixed inside the pipe body (2) to be stretched or compressed. The wavelength offset in the optical fiber (13) reflects the settlement displacement of the rock layer. The sleeve (1) is equipped with a transmission mechanism. The transmission mechanism uses the central shaft (20) to rotate and change the diameter of the tube body (2). After the tube body (2) enters the monitoring hole, it recovers its original diameter under its own elasticity. The tube body (2) can be interference-fitted into the energy-absorbing part of the spiral structure in the monitoring hole, so that the initial structure of the auxiliary optical fiber (13) changes and is used to monitor the settlement of the rock layer. A pre-fixing component, which is controlled by a transmission mechanism to pre-fix the tube body (2) when the diameter of the tube body (2) is reset; The transverse monitoring component is installed together with the optical fiber (13) inside the pipe body (2). One end of the transverse monitoring component is in contact with the central axis (20) to support the pipe body (2). At the same time, the configured displacement sensor can be used to monitor the transverse displacement of the rock layer.

2. The device for observing the dynamic settlement of the overlying roof strata in a mining goaf according to claim 1, characterized in that: Multiple optical fibers (13) are U-shaped, with one end connected to a light source and the other end connected to a light-receiving component. Multiple arc-shaped sections (6) are provided on the two vertical sections of the optical fiber (13). A straight mounting section (12) is formed between two adjacent arc-shaped sections (6). When the spiral section (7) on the tube (2) is stretched or compressed, the arc-shaped section (6) deforms, so that the wavelength shift in the optical fiber (13) reflects the settlement displacement of the rock layer. The openings of the arc-shaped sections (6) on the multiple optical fibers (13) all face the spiral groove, so that the openings of the arc-shaped sections (6) on the optical fiber (13) are distributed in a spiral path.

3. The device for observing the dynamic settlement of the overlying roof strata in a mining goaf according to claim 1, characterized in that: The inner side of the tube (2) is provided with a spiral groove on the spiral part (7), and a spiral fiber core (11) is installed in the spiral groove. The spiral fiber core (11) can deform with the change of the spiral part (7), so that the wavelength shift in the optical fiber (13) reflects the settlement displacement of the rock layer.

4. The device for observing the dynamic settlement of the overlying basic roof strata in a mining goaf according to claim 1, characterized in that: The transmission mechanism includes a central shaft (20) and a sleeve (1). The lower end of the sleeve (1) is provided with a flared part (10). The flared part (10) is inserted into the upper end of the tube body (2) and fixedly connected by bolts. Two circular plates (23) are fixedly connected inside the sleeve (1). The center of the lower circular plate (23) is rotatably connected to the shaft wall of the central shaft (20) through a sealed bearing. A worm gear (25) is fixedly connected to the shaft wall of the central shaft (20). A worm (24) is meshed on one side of the worm gear (25). A motor (22) is fixedly connected to the lower circular plate (23). The output end of the motor (22) is fixedly connected to one end of the worm (24). Two perforated rubber blocks (21) are fixedly connected between the upper circular plate (23) and the lower circular plate (23). The lower end of the tube (2) is fixedly connected to a ring (5). A connecting component connected to the central shaft (20) is installed inside the ring (5). The torque transmitted by the connecting component through the central shaft (20) causes the spiral part (7) installed on the tube (2) to deform and reduce its diameter. At the same time, the reverse rotation of the transmission mechanism can also apply a certain torque to the tube (2), so that the tube (2) can be stably installed in the monitoring hole.

5. The device for observing the dynamic settlement of the overlying basic roof strata in a mining goaf according to claim 4, characterized in that: The connecting assembly includes an annular plate (31) and a base plate (34). The annular plate (31) and the base plate (34) are both fixed inside the ring (5). A plurality of rectangular blocks (32) are fixedly connected between the annular plate (31) and the base plate (34). The lower end of the central shaft (20) is rotatably connected to the base plate (34) through a sealed bearing. A plurality of brake rods (33) are fixedly connected to the shaft wall of the central shaft (20). One end of each brake rod (33) extends between the annular plate (31) and the base plate (34) and is located on one side of the rectangular block (32).

6. The device for observing the dynamic settlement of the overlying roof strata in a mining goaf according to claim 5, characterized in that: A connecting ring (9) is installed at the upper end of the sleeve (1). The outer diameter of the connecting ring (9) matches the inner diameter of the ring (5). The side wall of the ring (5) is fitted with a fixing bolt connected to the connecting ring (9) through a round hole.

7. The device for observing the dynamic settlement of the overlying basic roof strata in a mining goaf according to claim 1, characterized in that: The pre-fixing assembly includes multiple rectangular tubes (26). Multiple rectangular tubes (26) are fixedly installed on the wall of the sleeve (1) through multiple rectangular openings. One end of each rectangular tube (26) is sealed. A fixing block (8) is slidably fitted inside each of the multiple rectangular tubes (26). Two guide rods (28) are fitted onto one side of each fixing block (8) through blind holes. One end of each guide rod (28) is fixed to one side of the rectangular tube (26). A [missing information - likely related to a specific type of guide rod] is fitted onto the wall of each guide rod (28). A spring (27) is set between the fixed block (8) and one side of the sealed end of the rectangular tube (26). When the pull rope (29) is released, the elastic force of the spring (27) pushes the fixed block (8) to contact the inner side of the monitoring hole. A pull rope (29) is fixedly connected to one side of the fixed block (8). A take-up reel (30) is fixedly connected to the shaft wall of the central shaft (20). One end of the pull rope (29) passes through the rectangular tube (26) and is fixed on the take-up reel (30).

8. The device for observing the dynamic settlement of the overlying basic roof strata in a mining goaf according to claim 7, characterized in that: The side wall of the pull rope (29) is fitted with a plastic bushing, which is fixed at the center of one side of the rectangular tube (26). The edge of the reel (30) is provided with an anti-rolling edge.

9. The device for observing the dynamic settlement of the overlying basic roof strata in a mining goaf according to claim 1, characterized in that: The transverse monitoring component includes a transverse tube (18), which is a rectangular structure and has a fixed base (19) fixedly connected to one end. The fixed base (19) is provided with a card holder, and the card holder is provided with a fixing part that matches the diameter of the optical fiber (13). The fixed base (19) and the card holder are fixed to the inner wall of the tube body (2) by bolts. A linear displacement sensor (16) is fixedly connected inside the transverse tube (18). A slider (14) is fixedly connected to one end of the measuring rod of the linear displacement sensor (16). One end of the slider (14) extends to the transverse side and contacts the shaft wall of the central shaft (20) through the provided arc groove (17). A reset spring (15) is provided on the rod wall of the measuring rod of the linear displacement sensor.

10. The device for observing the dynamic settlement of the overlying roof strata in a mining goaf according to claim 1, characterized in that: The side wall of the tube (2) is fixedly connected with a plurality of conical blocks (3). The conical blocks are installed on the spiral part (7) and distributed in a spiral route. The plurality of conical blocks (3) are distributed circumferentially relative to the tube (2) to form a conical fixing part, and the diameter of the conical fixing part is larger than the diameter of the tube (2).

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