Coal mine roof monitoring device based on fiber bragg grating

Abstract

The invention discloses a coal mine roof monitoring device based on a fiber bragg grating, and the device comprises a housing, the inner side of which is provided with a mounting groove; the rope winding drums are rotationally mounted at the two ends of the inner side of the mounting groove, coil springs are arranged on the inner sides of the rope winding drums, and steel wire ropes are wound on the rope winding drums; the claw is fixed at one end of the steel wire rope; the speed reducer is fixed to the edge of the inner side of the mounting groove, and one end of the speed reducer is connected with a rotating shaft; through the arrangement of the rope winding drum, the transmission wheel, the speed reducer, the rotating shaft and the fiber bragg grating detection assembly, the device is compact in structure, easy and convenient to adjust and high in reliability, and the moisture resistance and corrosion resistance of the bed separation instrument are improved based on the measurement mode of the fiber bragg grating principle; conversion from large displacement to small deformation is achieved, and large-range movement of a roof rock stratum can be measured.

Description

Technical Field

[0001] The present invention specifically relates to a coal mine roof monitoring device based on fiber Bragg grating. Background Art

[0002] A roof separation indicator is a special monitoring instrument for monitoring the movement of roof strata. By analyzing its results, the occurrence of roof collapse accidents can be effectively prevented, ensuring the safe production of coal mines. At present, most roof separation indicators use the principle of electrical measurement for measurement, and there are problems in actual application such as poor moisture and corrosion resistance of electronic devices and short service life. To overcome the above problems, sensors manufactured based on the principle of fiber optic sensing measure external physical quantities by measuring the wavelength of light, and have the advantages of strong adaptability to harsh environments, strong anti-electromagnetic interference ability, and high precision, enabling the sensors to work stably in the harsh environment of coal mine shafts, such as the patent number: 202023094956.2, titled: A fiber optic passive roof separation indicator, and the patent number: 201410033068.X, titled: A fiber Bragg grating separation device for monitoring the deformation of rock roofs.

[0003] However, due to the limited strain range monitored by fiber Bragg gratings, the designed separation indicator still has the problem of a small separation monitoring range, which is inconvenient for detecting large-scale movements. Therefore, it is necessary to develop a coal mine roof separation measuring device with a large measurement range and high reliability to achieve truly reliable measurement of the movement of roof strata in kilometer-deep shafts. For this purpose, we propose a coal mine roof monitoring device based on fiber Bragg grating. Summary of the Invention

[0004] The purpose of the present invention is to provide a coal mine roof monitoring device based on fiber Bragg grating to solve the problems raised in the above background art.

[0005] To achieve the above purpose, the present invention provides the following technical solution: A coal mine roof monitoring device based on fiber Bragg grating, comprising:

[0006] A housing, with an installation groove provided inside the housing;

[0007] A rope winding drum, rotatably installed at both ends inside the installation groove, and a coil spring is provided inside the rope winding drum, and a steel wire rope is wound around the rope winding drum;

[0008] A claw, fixed to one end of the steel wire rope;

[0009] A speed reducer, fixed to the inner edge of the installation groove, and one end of the speed reducer is connected to a rotating shaft, and a transmission wheel cooperating with the steel wire rope is provided on the rotating shaft;

[0010] A fiber Bragg grating detection assembly, arranged at the other end of the speed reducer to detect the movement of the steel wire rope.

[0011] Preferably, the fiber Bragg grating detection assembly includes a lead screw shaft, a slider, a spring, a fiber Bragg grating, a guide rail and an S-shaped fixing block. The lead screw shaft is arranged at the other end of the speed reducer. A slider is connected to the lead screw shaft through a threaded portion. The guide rail is fixed to the inner wall of the installation groove to cooperate with the slider to guide it. An S-shaped fixing block is arranged at one end of the upper surface of the guide rail. The spring is sleeved on the lead screw shaft, and the two ends of the spring correspond to the slider and the S-shaped fixing block respectively. The fiber Bragg grating is arranged on the top of the S-shaped fixing block to detect the deformation of the S-shaped fixing block.

[0012] Preferably, the cross-section of the S-shaped fixing block is "S" shaped.

[0013] Preferably, a rib is fixed on the guide rail, and a groove matching the rib is formed on the lower surface of the slider.

[0014] Preferably, there are two sets of the fiber Bragg grating detection assembly and the wire rope.

[0015] Preferably, a through hole is formed through the middle of the inner side of the housing. A transverse connecting cylinder for guiding the wire rope is arranged inside the through hole, and one end of the transverse connecting cylinder corresponds to the transmission wheel. A longitudinal connecting cylinder is fixed on the transverse connecting cylinder.

[0016] Preferably, two oil storage grooves are symmetrically arranged along the longitudinal connecting cylinder on the upper surface of the transverse connecting cylinder. A connecting hole communicating with the inside of the transverse connecting cylinder is formed through the lower end of the inner side of the oil storage groove, and an inlet is formed at the upper end of the inner side of the oil storage groove.

[0017] Preferably, a brush is arranged along the circumferential direction inside the transverse connecting cylinder.

[0018] Preferably, there are two sets of the rope winding drum and the transmission wheel.

[0019] Preferably, the housing is rectangular.

[0020] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0021] By providing a rope winding drum, a transmission wheel, a speed reducer, a rotating shaft and a fiber Bragg grating detection assembly, the present invention avoids the disadvantages of small separation detection range and poor anti-corrosion effect in the traditional technology. The device has a compact structure, simple adjustment and strong reliability. Based on the measurement method of the fiber Bragg grating principle, the moisture and corrosion resistance of the separation meter is improved. The new measurement structure realizes the conversion from large displacement to small deformation through a worm and gear speed reducer and a lead screw, and can measure the large-range movement of the roof rock formation, improving the monitoring range and effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 is a schematic structural diagram of the present invention;

[0023] Figure 2 Schematic structural diagram of the fiber Bragg grating detection component of the present invention;

[0024] Figure 3 Schematic structural diagram of the S-shaped fixing block of the present invention;

[0025] Figure 4 Schematic cross-sectional structural diagram of the horizontal connecting cylinder of the present invention.

[0026] In the figure: 1, outer shell; 101, installation groove; 102, through hole; 2, steel wire rope; 3, horizontal connecting cylinder; 4, claw; 5, rope winding drum; 6, transmission wheel; 7, reducer; 8, rotating shaft; 9, longitudinal connecting cylinder; 10, lead screw shaft; 11, slider; 12, spring; 13, fiber Bragg grating; 14, guide rail; 15, S-shaped fixing block; 16, oil storage tank; 17, inlet; 18, connection hole; 19, brush. Specific implementation manners

[0027] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0028] Please refer to Figures 1-4 , the present invention provides a technical solution: a coal mine roof monitoring device based on fiber Bragg grating, including:

[0029] Outer shell 1, with an installation groove 101 opened inside the outer shell 1;

[0030] Rope winding drum 5, rotatably installed at both ends inside the installation groove 101, and a coil spring is provided inside the rope winding drum 5, and a steel wire rope 2 is wound on the rope winding drum 5;

[0031] Claw 4, fixed to one end of the steel wire rope 2, facilitating the cooperative connection with the rock formation at the coal mine roof during monitoring;

[0032] Reducer 7, fixed to the inner edge of the installation groove 101, and one end of the reducer 7 is connected to a rotating shaft 8, facilitating the reduction of the rotation speed of the transmission wheel 6 and transmitting it to the lead screw shaft 10, and a transmission wheel 6 cooperating with the steel wire rope 2 is provided on the rotating shaft 8;

[0033] Fiber Bragg grating detection component, arranged at the other end of the reducer 7 to detect the movement of the steel wire rope 2, facilitating the detection of the reduced rotation speed and giving an early warning when movement occurs.

[0034] Preferably, the fiber Bragg grating detection assembly includes a lead screw shaft 10, a slider 11, a spring 12, a fiber Bragg grating 13, a guide rail 14 and an S-shaped fixing block 15. The lead screw shaft 10 is arranged at the other end of the speed reducer 7. A slider 11 is connected to the lead screw shaft 10 through a threaded portion. The guide rail 14 is fixed to the inner wall of the installation groove 101 to cooperate with the slider 11 to guide it. When the rock formation at the coal mine roof loosens, it drives the steel wire rope 2 to move, and then drives the slider 11 to move, so as to push one end of the spring 12 to move. An S-shaped fixing block 15 is arranged at one end of the upper surface of the guide rail 14. The spring 12 is sleeved on the lead screw shaft 10, and both ends of the spring 12 correspond to the slider 11 and the S-shaped fixing block 15 respectively. The fiber Bragg grating 13 is arranged on the top of the S-shaped fixing block 15 to detect the deformation of the S-shaped fixing block 15, so as to detect the movement of the rock formation at the coal mine roof by monitoring the extrusion force of the spring 12 on the S-shaped fixing block 15.

[0035] Preferably, the cross-section of the S-shaped fixing block 15 is "S"-shaped, which is convenient for better deformation effect.

[0036] Preferably, a convex strip is fixed on the guide rail 14, and a groove matching the convex strip is opened on the lower surface of the slider 11, which is convenient for the slider 11 to move horizontally better.

[0037] Preferably, two sets of fiber Bragg grating detection assemblies and steel wire ropes 2 are provided, which is convenient for monitoring different depths of the rock formation at the coal mine roof.

[0038] Preferably, a through hole 102 is penetrated through the middle of the inner side of the housing 1. A transverse connecting cylinder 3 for guiding the steel wire rope 2 is arranged inside the through hole 102, and one end of the transverse connecting cylinder 3 corresponds to the transmission wheel 6. A longitudinal connecting cylinder 9 is fixed on the transverse connecting cylinder 3, which is convenient for guiding the low steel wire rope 2.

[0039] Preferably, two oil storage grooves 16 are symmetrically arranged on the upper surface of the transverse connecting cylinder 3 along the longitudinal connecting cylinder 9. A connecting hole 18 communicating with the inside of the transverse connecting cylinder 3 is penetrated through the lower end of the inner side of the oil storage groove 16, and an inlet 17 is opened at the upper end of the inner side of the oil storage groove 16, which is convenient for lubricating the surface of the steel wire rope 2, improving its surface anti-wear effect, and reducing the corrosion damage of the external environment to the steel wire rope 2 through the lubricating oil.

[0040] Preferably, a brush 19 is arranged along the circumferential direction inside the transverse connecting cylinder 3, which is convenient for evenly coating the lubricating oil on the surface of the steel wire rope 2.

[0041] Preferably, two sets of rope winding drums 5 and transmission wheels 6 are provided.

[0042] Preferably, the housing 1 is rectangular, which is convenient for assembling multiple rope winding drums 5 for monitoring.

[0043] Working principle and usage process of the present invention: When in use, a borehole passing through multiple horizons is drilled in the rock formation by the roadway roof, and then the steel wire rope 2 is pulled to rotate the rope winding drum 5 to release the steel wire rope 2, so that the claw 4 at one end of the steel wire rope 2 is fixed in the borehole. At the same time, the steel wire rope 2 drives the transmission wheel 6 to rotate, and the rotation of the transmission wheel 6 is transmitted to the reducer 7 through the rotating shaft 8. After being decelerated by the reducer 7, the rotational force is transmitted to the lead screw shaft 10, and the lead screw shaft 10 rotates to drive the slider 11 to move. The slider 11 pushes one end of the spring 12 to move, and then the other end of the spring 12 causes compressive deformation of the S-shaped fixing block 15. The fiber Bragg grating 13 detects the deformation of the S-shaped fixing block 15. Similarly, another claw 4 can also be fixed in boreholes at different depths, and the deformation is detected by another fiber Bragg grating 13, so as to facilitate early warning of disasters when large-scale movement occurs in the roof rock formation. In addition, when the steel wire rope 2 is pulled out from the rope winding drum 5, the steel wire rope 2 moves inside the transverse connecting cylinder 3. Through the lubricating oil flowing out from the inside of the oil storage tank 16 and the brushing of the steel wire rope 2 surface by the brush 19, it is convenient to maintain the steel wire rope 2 and improve the corrosion resistance effect of the steel wire rope 2 surface.

[0044] Although the embodiments of the present invention have been shown and described, for those of ordinary skill in the art, it can be understood that various changes, modifications, substitutions and variations can be made to these embodiments without departing from the principles and spirit of the present invention. The scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A coal mine roof monitoring device based on fiber grating, characterized in that: include: A housing (1), wherein a mounting groove (101) is provided on the inner side of the housing (1); A rope winding drum (5) is rotatably mounted at two ends of the inner side of the mounting groove (101), and a winding spring is provided on the inner side of the rope winding drum (5). A steel wire rope (2) is wound on the rope winding drum (5); A claw (4) is fixed to one end of the steel wire rope (2); A reducer (7) is fixed to the inner edge of the mounting groove (101), and one end of the reducer (7) is connected to a rotating shaft (8), and the rotating shaft (8) has a transmission wheel (6) that cooperates with the steel wire rope (2); The fiber grating detection component is arranged at the other end of the reducer (7) to detect the movement of the steel wire rope (2).

2. A coal mine roof monitoring device based on fiber grating according to claim 1, characterized in that: The fiber grating detection assembly comprises a screw shaft (10), a slider (11), a spring (12), a fiber grating (13), a guide rail (14) and an S-shaped fixed block (15). The screw shaft (10) is arranged at the other end of the reducer (7). The screw shaft (10) is connected with the slider (11) through a threaded portion. The guide rail (14) is fixed to the inner wall of the mounting groove (101) to cooperate with the slider (11) to guide it. An S-shaped fixed block (15) is arranged at one end of the upper surface of the guide rail (14). The spring (12) is sleeved on the screw shaft (10), and the two ends of the spring (12) correspond to the slider (11) and the S-shaped fixed block (15) respectively. The fiber grating (13) is arranged on the top of the S-shaped fixed block (15) to detect the deformation of the S-shaped fixed block (15).

3. A coal mine roof monitoring device based on fiber grating according to claim 2, characterized in that: The cross section of the S-shaped fixing block (15) is "S"-shaped.

4. A coal mine roof monitoring device based on fiber grating according to claim 2, characterized in that: A convex strip is fixed on the guide rail (14), and a groove matching the convex strip is formed on the lower surface of the sliding block (11).

5. The coal mine roof monitoring device based on fiber grating according to claim 1, characterized in that: The fiber grating detection component and the steel wire rope (2) are both provided at two locations.

6. A coal mine roof monitoring device based on fiber grating according to claim 1, characterized in that: A through hole (102) is provided through the middle of the inner side of the housing (1), a transverse connecting tube (3) for guiding the steel wire rope (2) is provided inside the through hole (102), one end of the transverse connecting tube (3) corresponds to the transmission wheel (6), and a longitudinal connecting tube (9) is fixed on the transverse connecting tube (3).

7. A coal mine roof monitoring device based on fiber grating according to claim 6, characterized in that: Two oil storage grooves (16) are symmetrically arranged on the upper surface of the transverse connecting tube (3) along the longitudinal connecting tube (9), a connecting hole (18) is penetrated through the lower end of the inner side of the oil storage groove (16) and connected to the inside of the transverse connecting tube (3), and an inlet (17) is opened at the upper end of the inner side of the oil storage groove (16).

8. A coal mine roof monitoring device based on fiber grating according to claim 6, characterized in that: A brush (19) is arranged along the circumference of the inner side of the transverse connecting tube (3).

9. A coal mine roof monitoring device based on fiber grating according to claim 1, characterized in that: The rope winding drum (5) and the transmission wheel (6) are both provided at two locations.

10. The coal mine roof monitoring device based on fiber grating according to claim 1, characterized in that: The housing (1) is rectangular.

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