Stress monitoring device for overlying strata in coal mine stope

Abstract

The invention relates to the technical field of stress monitoring, in particular to a stress monitoring device for overlying strata in a coal mine stope. The invention provides the stress monitoring device for the overlying strata in the coal mine stope, which can automatically stop injecting water into the expansion rubber sleeve and avoid excessive expansion of the expansion rubber sleeve. A coal mine stope overlying rock stress monitoring device comprises an external sleeve, a connecting assembly and the like, the lower side of the external sleeve is provided with the connecting assembly, the connecting assembly is composed of an upper connecting cylinder and a lower connecting cylinder, the connecting cylinders are connected through threads, and the connecting cylinder on the upper side is connected with the external sleeve through threads. When the expansion rubber sleeve expands, the contact block moves outwards to make contact with the inner wall of a drill hole, when the expansion rubber sleeve continues to expand, the contact block moves inwards to push the threaded column to move inwards, the threaded sleeve rotates, the rotating valve is driven to rotate, the branch pipe is closed through the rotating valve, and the purposes that water injection into the expansion rubber sleeve can be automatically stopped, and the drilling efficiency is improved are achieved. And excessive expansion of the expansion rubber sleeve is avoided.

Description

Technical Field

[0001] The invention relates to the technical field of stress monitoring, and in particular to a device for monitoring stress of overlying rock strata in a coal mine. Background Art

[0002] During coal mining, coal seam mining causes stress redistribution, which in turn causes the movement of overlying rock strata, which is the root cause of disasters such as rock burst, water inrush and sand penetration, tunnel collapse, and surface subsidence. Real-time monitoring of the movement of overlying rock strata under the influence of mining and summarizing the activity laws of overlying rock strata under the influence of mining are of great significance to the safe and efficient mining of coal resources.

[0003] Between coal seams, between thick coal seams and between coal groups, the coal seams, layers or coal groups with lower elevations are mined first, and then the coal seams, layers or coal groups with higher elevations are mined. This is called the ascending mining sequence. When the coal seams are mined in the ascending sequence, the lower coal seams have been mined. Due to the influence of the mining of the lower coal seams, the original stress state of the upper coal seams may be destroyed. Therefore, the stress state of the overburden in the mining area needs to be strengthened to ensure the safety of coal mining.

[0004] The existing overburden stress monitoring device for coal mine working sites usually injects water into an expansion rubber sleeve to expand the expansion rubber sleeve to fix the detection tube in the borehole, and then uses a fiber optic Bragg grating detector to monitor the stress in the borehole. However, since the amount of water injected into the expansion rubber sleeve is controlled by staff when water is injected into the expansion rubber sleeve, too much water may be injected, causing the expansion rubber sleeve to expand excessively, thereby reducing the service life of the expansion rubber sleeve and making the expansion rubber sleeve prone to rupture.

[0005] Therefore, a stress monitoring device for overlying strata in coal mines has been developed, which can automatically stop injecting water into the expansion rubber sleeve to avoid excessive expansion of the expansion rubber sleeve. Summary of the invention

[0006] In order to overcome the disadvantages of the existing overlying strata stress monitoring device for coal mine workings, when water is injected into the expansion rubber sleeve, the water injection amount is controlled by the staff, and too much water may be injected, resulting in excessive expansion of the expansion rubber sleeve, reducing the service life of the expansion rubber sleeve, and the expansion rubber sleeve is prone to rupture. The present invention provides a coal mine working site overlying strata stress monitoring device which can automatically stop injecting water into the expansion rubber sleeve to avoid excessive expansion of the expansion rubber sleeve.

[0007] A device for monitoring stress of overlying strata in a coal mining field comprises an external sleeve, a connecting assembly, a detection mechanism and a water shut-off mechanism. A connecting assembly is provided on the lower side of the external sleeve, and the connecting assembly consists of two upper and lower connecting tubes, which are connected by threads. The upper connecting tube is connected to the external sleeve by threads. The external sleeve and the connecting tube are provided with detection mechanisms capable of monitoring stress of overlying strata, and the detection mechanism is provided with a water shut-off mechanism capable of automatically shutting off water.

[0008] In a preferred embodiment of the present invention, the upper portion of the external sleeve is semicircular.

[0009] In a preferred embodiment of the present invention, a monitoring groove is provided on the connecting tube.

[0010] In a preferred embodiment of the present invention, the detection mechanism includes a branch pipe, a first water pipe, a second water pipe, an expansion rubber sleeve, a fixed boot, a fixed frame and a fiber optic Bragg grating detector. The branch pipe is placed inside the external sleeve and the connecting tube. The branch pipe is a hollow tube. The upper and lower parts of the branch pipe are connected to multiple first water pipes, the upper and lower parts of the branch pipe are connected to the second water pipe, the second water pipe is located below the first water pipe, an expansion rubber sleeve is connected between the vertically adjacent first water pipes and second water pipes, multiple fixed boots are connected to the outside of the expansion rubber sleeve, multiple fixed frames are connected to the outside of the expansion rubber sleeve, the fixed frame is located between two adjacent fixed boots, and the fixed frame is clamped with a fiber optic Bragg grating detector. Water is passed into the branch pipe so that water is injected from the first water pipe and the second water pipe into the expansion rubber sleeve, so that the expansion rubber sleeve expands and pushes out the fixed boot, so that the fixed boot passes through the connecting tube and contacts the inner wall of the borehole, so that the connecting tube is fixed in the borehole, and the stress of the overburden layer is monitored by the fiber optic Bragg grating detector on the fixed frame.

[0011] In a preferred embodiment of the present invention, the water shut-off mechanism includes a contact block, a threaded column, a threaded sleeve, a rotary valve and a first spring. The middle part of the expansion rubber sleeve is rotatably connected to the threaded sleeve, the outer side of the threaded sleeve is threadedly connected to the threaded column, the outer side of the threaded column is connected to the contact block, the contact blocks are in contact with adjacent fixed boots, and the rotary valve is slidably connected between two adjacent threaded sleeves. The rotary valve is rotatably connected to the branch pipe, and the first spring is arranged between the threaded column and the adjacent rotary valve. When the expansion rubber sleeve expands, the contact block moves outward and contacts the inner wall of the borehole. When the expansion rubber sleeve continues to expand, the contact block moves inward, pushing the threaded column inward, causing the threaded sleeve to rotate, driving the rotary valve to rotate, and causing the rotary valve to close the branch pipe.

[0012] In a preferred embodiment of the present invention, the contact blocks are all arc-shaped.

[0013] In a preferred embodiment of the present invention, a shock absorbing mechanism is also included, which includes a damping sleeve, a support rod, a damping block and a second spring. The upper and lower parts of the branch pipe are connected to multiple damping sleeves, and the damping sleeves are slidably connected to the support rods, which are connected to adjacent expansion rubber sleeves, and the support rods are connected to damping blocks, which are slidably connected to adjacent damping sleeves, and the second spring is connected between the damping blocks and the adjacent damping sleeves. When the expansion rubber sleeve shakes, the support rod moves, driving the damping block to move in the damping sleeve, and the damping block and the support rod are kept in relative positions by the action of the second spring to support the expansion rubber sleeve.

[0014] In a preferred embodiment of the present invention, a packaging sleeve is also included, and the fiber optic grating detector is clamped with the packaging sleeve.

[0015] In a preferred embodiment of the present invention, the packaging sleeves are all made of transparent material.

[0016] In a preferred embodiment of the present invention, an electric heat processor is also included, and the packaging sleeve is connected to the electric heat processor.

[0017] Compared with the prior art, the present invention has the following advantages: 1. In the present invention, while the expansion rubber sleeve expands, the contact block moves outward to contact the inner wall of the borehole. When the expansion rubber sleeve continues to expand, the contact block moves inward, pushing the threaded column to move inward, causing the threaded casing to rotate, driving the rotary valve to rotate, and causing the rotary valve to close the branch pipe, thereby achieving the effect of automatically stopping the injection of water into the expansion rubber sleeve and avoiding excessive expansion of the expansion rubber sleeve.

[0018] 2. When the expansion rubber sleeve shakes, the support rod moves, driving the damping block to move in the damping sleeve. The damping block and the support rod are kept in relative positions through the action of the second spring, thereby supporting the expansion rubber sleeve, thereby improving the stability of the expansion rubber sleeve and preventing the fixing boot from detaching from the inner wall of the drilled hole.

[0019] 3. The present invention seals the fiber Bragg grating detector by means of a packaging sleeve, thereby achieving the effect of preventing dust from affecting the detection result of the fiber Bragg grating detector.

[0020] 4. The present invention adjusts the temperature in the packaging sleeve through an electric heating processor, thereby achieving the effect of preventing the temperature from affecting the detection result of the fiber grating detector. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a schematic diagram of the three-dimensional structure of the present invention.

[0022] Figure 2 It is a partial three-dimensional structural schematic diagram of the present invention.

[0023] Figure 3It is a partial three-dimensional structural cross-sectional view of the present invention.

[0024] Figure 4 It is a partial three-dimensional structural schematic diagram of the present invention.

[0025] Figure 5 It is a partial three-dimensional structural schematic diagram of the present invention.

[0026] Figure 6 It is a partial three-dimensional structural schematic diagram of the present invention.

[0027] Figure 7 It is a partial three-dimensional structural cross-sectional view of the present invention.

[0028] Figure 8 It is a partial three-dimensional structural cross-sectional view of the present invention.

[0029] Fig. 9 It is a partial three-dimensional structural cross-sectional view of the present invention.

[0030] Fig.10 It is a partial three-dimensional structural schematic diagram of the present invention.

[0031] Fig.11 It is a partial three-dimensional structural schematic diagram of the present invention.

[0032] Fig.12 It is a partial three-dimensional structural cross-sectional view of the present invention.

[0033] Fig.13 It is a schematic diagram of a novel three-dimensional structure of this practical part.

[0034] Fig.14 It is a schematic diagram of a novel three-dimensional structure of this practical part.

[0035] Among them, the above-mentioned drawings include the following figure marks: 1. external sleeve, 2. connecting tube, 3. detection mechanism, 31. branch pipe, 32. first water pipe, 33. second water pipe, 34. expansion rubber sleeve, 35. fixing boot, 36. fixing frame, 37. fiber optic Bragg grating detector, 4. water shut-off mechanism, 41. contact block, 42. threaded column, 43. threaded sleeve, 44. rotary valve, 45. first spring, 5. shock absorbing mechanism, 51. damping sleeve, 52. support rod, 53. damping block, 54. second spring, 6. packaging sleeve, 7. electric heat processor. DETAILED DESCRIPTION

[0036] First of all, it should be pointed out that in the different described embodiments, the same parts are provided with the same reference numerals or the same component names, wherein the disclosure contained in the entire description can be transferred to the same parts with the same reference numerals or the same component names. Selected positional descriptions in the description, such as top, bottom, lateral, etc., also refer to the directly described and shown figures and are transferred to the new positions in the case of a change in position.

[0037] A device for monitoring stress of overburden in coal mines, such as Figure 1-Figure 14 As shown, it includes an external sleeve 1, a connecting assembly, a detection mechanism 3 and a water shut-off mechanism 4. A connecting assembly is provided on the lower side of the external sleeve 1. The upper part of the external sleeve 1 is semicircular, which is convenient for pushing into the borehole. The connecting assembly consists of two upper and lower connecting tubes 2. The connecting tubes 2 are connected by threads. The upper connecting tube 2 is connected to the external sleeve 1 by threads. A monitoring groove is opened on the connecting tube 2 to facilitate monitoring of the stress of the overburden layer. The external sleeve 1 and the connecting tube 2 are provided with a detection mechanism 3, and the detection mechanism 3 is provided with a water shut-off mechanism 4.

[0038] like Figure 1 , Figure 3 , Figure 4 , Figure 5 and Figure 6 As shown, the detection mechanism 3 includes a branch pipe 31, a first water pipe 32, a second water pipe 33, an expansion rubber sleeve 34, a fixing shoe 35, a fixing frame 36 and a fiber optic Bragg grating detector 37. The branch pipe 31 is placed inside the external sleeve 1 and the connecting tube 2. The branch pipe 31 is a hollow pipe. The upper and lower parts of the branch pipe 31 are connected to two first water pipes 32. The upper and lower parts of the branch pipe 31 are connected to the second water pipe 33. The second water pipe 33 is located below the first water pipe 32. An expansion rubber sleeve 34 is connected between the vertically adjacent first water pipes 32 and second water pipes 33. Four fixing shoes 35 are connected to the outside of the expansion rubber sleeve 34. Two fixing frames 36 are connected to the outside of the expansion rubber sleeve 34. The fixing frame 36 is located between two adjacent fixing shoes 35. The fixing frame 36 is clamped with a fiber optic Bragg grating detector 37.

[0039] like Figure 5 , Figure 7 , Figure 8 , Fig. 9 and Fig.10As shown, the water shut-off mechanism 4 includes a contact block 41, a threaded column 42, a threaded sleeve 43, a rotary valve 44 and a first spring 45. The middle part of the expansion rubber sleeve 34 is rotatably connected with the threaded sleeve 43, the outer side of the threaded sleeve 43 is threadedly connected with the threaded column 42, the outer side of the threaded column 42 is connected with the contact block 41, the contact blocks 41 are all arc-shaped, which is convenient for contacting the inner wall of the borehole, the contact blocks 41 are in contact with adjacent fixed boots 35, and the rotary valve 44 is slidably connected between two adjacent threaded sleeves 43. The rotary valve 44 is rotatably connected to the branch pipe 31, and a first spring 45 is arranged between the threaded column 42 and the adjacent rotary valve 44.

[0040] When using the present invention, the connecting tubes 2 are first connected to each other, and then the external sleeve 1 is connected to the connecting tube 2. After that, the external sleeve 1 is pushed into the preset borehole of the overburden layer through the connecting tube 2, and then the branch pipe 31 is placed in the connecting tube 2. After that, water is passed into the branch pipe 31, so that water is injected into the expansion rubber sleeve 34 from the first water pipe 32 and the second water pipe 33, so that the expansion rubber sleeve 34 expands to push out the fixing shoe 35, so that the fixing shoe 35 passes through the connecting tube 2 and contacts the inner wall of the borehole, so that the connecting tube 2 is fixed in the borehole, and the stress of the overburden layer is monitored by the fiber optic grating detector 37 on the fixing frame 36. While the expansion sleeve 34 expands, the contact block 41 moves outward and contacts the inner wall of the borehole. When the expansion sleeve 34 continues to expand, the contact block 41 moves inward, and the first spring 45 is squeezed and contracted, pushing the threaded column 42 to move inward, causing the threaded sleeve 43 to rotate, driving the rotary valve 44 to rotate, so that the rotary valve 44 closes the branch pipe 31, thereby automatically stopping the injection of water into the expansion sleeve 34 and avoiding excessive expansion of the expansion sleeve 34. When the expansion sleeve 34 retracts, the first spring 45 rebounds, causing the contact block 41 to reset.

[0041] like Figure 5 , Fig.11 and Fig.12 As shown, a shock absorbing mechanism 5 is also included, which includes a damping sleeve 51, a support rod 52, a damping block 53 and a second spring 54. The upper and lower parts of the branch pipe 31 are connected to two damping sleeves 51, and the damping sleeves 51 are slidably connected to the support rods 52. The support rods 52 are connected to adjacent expansion rubber sleeves 34. The support rods 52 are connected to damping blocks 53. The damping blocks 53 are slidably connected to adjacent damping sleeves 51, and second springs 54 are connected between the damping blocks 53 and adjacent damping sleeves 51.

[0042] When the expansion rubber sleeve 34 shakes, the support rod 52 moves, driving the damping block 53 to move in the damping sleeve 51. The damping block 53 and the support rod 52 are kept in relative positions through the force of the second spring 54 to support the expansion rubber sleeve 34, thereby improving the stability of the expansion rubber sleeve 34 and preventing the fixing boot 35 from detaching from the inner wall of the borehole.

[0043] like Fig.13 As shown, a packaging sleeve 6 is also included. The fiber optic grating detector 37 is clamped with the packaging sleeve 6. The packaging sleeve 6 is made of transparent material to facilitate detection.

[0044] like Fig.14 As shown, an electric heat processor 7 is also included, and the packaging sleeve 6 is connected to the electric heat processor 7.

[0045] The packaging sleeve 6 can seal the fiber Bragg grating detector 37 to prevent dust from affecting the detection result of the fiber Bragg grating detector 37 . The electric heat processor 7 can adjust the temperature inside the packaging sleeve 6 to prevent the temperature from affecting the detection result of the fiber Bragg grating detector 37 .

[0046] The above embodiments are only for illustrating the technical concept and features of the present invention, and their purpose is to enable people familiar with the technology to understand the content of the present invention and implement it accordingly, and they cannot be used to limit the protection scope of the present invention. Any equivalent changes or modifications made according to the spirit of the present invention should be included in the protection scope of the present invention.

Claims

1. A device for monitoring stress of overburden strata in a coal mine, characterized by: The invention comprises an external sleeve (1), a connection assembly, a detection mechanism (3) and a water shut-off mechanism (4); a connection assembly is provided on the lower side of the external sleeve (1); the connection assembly is composed of two upper and lower connection tubes (2); the connection tubes (2) are connected to each other by threads; the upper connection tube (2) is connected to the external sleeve (1) by threads; the external sleeve (1) and the connection tube (2) are provided with a detection mechanism (3) capable of monitoring the stress of the overburden stratum; and the detection mechanism (3) is provided with a water shut-off mechanism (4) capable of automatically shutting off the water.

2. The device for monitoring stress of overburden strata in a coal mine according to claim 1, characterized in that: The upper part of the external sleeve (1) is semicircular.

3. The device for monitoring stress of overburden strata in a coal mine according to claim 1, characterized in that: A monitoring groove is provided on the connecting tube (2).

4. The device for monitoring stress of overburden strata in a coal mine according to claim 1, characterized in that: The detection mechanism (3) comprises a branch pipe (31), a first water pipe (32), a second water pipe (33), an expansion rubber sleeve (34), a fixing shoe (35), a fixing frame (36) and a fiber optic Bragg grating detector (37). The branch pipe (31) is placed inside the external sleeve (1) and the connecting tube (2). The branch pipe (31) is a hollow pipe. The upper and lower parts of the branch pipe (31) are both connected to a plurality of first water pipes (32). The upper and lower parts of the branch pipe (31) are both connected to the second water pipe (33). The second water pipe (33) is located below the first water pipe (32). An expansion rubber sleeve (34) is connected between the vertically adjacent first water pipes (32) and the second water pipes (33). The expansion rubber sleeve (34) is provided outside the expansion rubber sleeve (34). A plurality of fixing boots (35) are connected to the sides of the branch pipe (31), a plurality of fixing frames (36) are connected to the outside of the expansion rubber sleeve (34), the fixing frames (36) are located between two adjacent fixing boots (35), and a fiber optic Bragg grating detector (37) is clamped on the fixing frames (36). Water is passed into the branch pipe (31), so that water is injected into the expansion rubber sleeve (34) from the first water pipe (32) and the second water pipe (33), so that the expansion rubber sleeve (34) expands to push out the fixing boot (35), so that the fixing boot (35) passes through the connecting tube (2) and contacts the inner wall of the borehole, so that the connecting tube (2) is fixed in the borehole, and the stress of the overburden layer is monitored by the fiber optic Bragg grating detector (37) on the fixing frame (36).

5. The device for monitoring stress of overburden strata in a coal mine according to claim 4, characterized in that: The water shut-off mechanism (4) comprises a contact block (41), a threaded column (42), a threaded sleeve (43), a rotary valve (44) and a first spring (45); the middle of the expansion rubber sleeve (34) is rotatably connected to the threaded sleeve (43); the outer side of the threaded sleeve (43) is threadedly connected to the threaded column (42); the outer side of the threaded column (42) is connected to the contact block (41); the contact block (41) is in contact with the adjacent fixed boot (35); the rotary valve (44) is slidably connected between two adjacent threaded sleeves (43); ), the rotary valves (44) are rotatably connected to the branch pipe (31), and a first spring (45) is arranged between the threaded column (42) and the adjacent rotary valve (44). When the expansion rubber sleeve (34) expands, the contact block (41) moves outward to contact the inner wall of the borehole. When the expansion rubber sleeve (34) continues to expand, the contact block (41) moves inward, pushing the threaded column (42) to move inward, so that the threaded sleeve (43) rotates, driving the rotary valve (44) to rotate, so that the rotary valve (44) closes the branch pipe (31).

6. The device for monitoring stress of overburden strata in a coal mine according to claim 5, characterized in that: The contact blocks (41) are all arc-shaped.

7. The device for monitoring stress of overburden strata in a coal mine according to claim 5, characterized in that: The invention also comprises a shock absorbing mechanism (5), the shock absorbing mechanism (5) comprising a damping sleeve (51), a support rod (52), a damping block (53) and a second spring (54), the upper and lower parts of the branch pipe (31) are both connected to a plurality of damping sleeves (51), the damping sleeves (51) are both slidably connected to the support rods (52), the support rods (52) are both connected to the adjacent expansion rubber sleeves (34), the support rods (52) are both connected to the damping blocks (53), and the damping blocks (53) are both ) are slidably connected to adjacent damping sleeves (51), and a second spring (54) is connected between the damping block (53) and the adjacent damping sleeves (51). When the expansion rubber sleeve (34) shakes, the support rod (52) moves, driving the damping block (53) to move in the damping sleeve (51). The damping block (53) and the support rod (52) are kept in relative positions by the action force of the second spring (54), thereby supporting the expansion rubber sleeve (34).

8. The device for monitoring stress of overburden strata in a coal mine according to claim 7, characterized in that: It also includes a packaging sleeve (6), and the fiber optic grating detector (37) is clamped with the packaging sleeve (6).

9. The device for monitoring stress of overburden strata in a coal mine according to claim 8, characterized in that: The packaging sleeves (6) are all made of transparent material.

10. The device for monitoring stress of overburden strata in a coal mine according to claim 8, characterized in that: It also includes an electric heat processor (7), and the packaging sleeve (6) is connected to the electric heat processor (7).

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