A monitoring and early warning device for cracks in mine subsidence areas

Abstract

This invention discloses a monitoring and early warning device for fissures in mine subsidence areas, relating to the field of monitoring and early warning technology. It includes a mine car and a support frame. A laser emitter is fixedly installed on the top of the mine car, and the laser emitter contains an emission module, a detection module, and a control module. A signal emitter is also fixedly installed on the top of the mine car. A square groove is formed on the surface of the mine car. The control module is electrically connected to the signal emitter. Support legs are fixedly installed at the bottom of the support frame, and positioning holes are formed on the surface of the support legs. Telescopic legs are slidably installed on the inner wall of the support legs, and adjustment holes are formed on the surface of the telescopic legs. A spring resets a deformation plate, which then limits the adjustment holes and positioning holes, allowing for quick adjustment of the length of the support legs and telescopic legs, reducing operational difficulty.

Description

Technical Field

[0001] The invention relates to the technical field of monitoring and early warning, and in particular to a monitoring and early warning device for cracks in a mine subsidence area. Background Art

[0002] Crack detection and early warning devices in mine subsidence areas are usually integrated systems based on modern sensing technology and data processing technology, aiming to timely detect and warn of possible risks of mine subsidence to ensure mine safety and production continuity.

[0003] The patent with the patent announcement number CN110132209B relates to a landslide monitoring and early warning device, including a fixed side fixed detection box, the fixed side fixed detection box is fixedly connected to an outer fixed detection box through a mechanical telescopic outer tube at the middle position near the collapse crack, the interior of the mechanical telescopic outer tube is provided with a plastic elastic hollow tube, and the fixed side fixed detection box and the outer fixed detection box are both located below the ground, the fixed side fixed detection box is fixedly connected to an adjustment control box at the bottom of the interior of the side near the outer fixed detection box, and the adjustment control box is provided with a signal transmitter receiver, a data comparator and a central processing unit. This patent relates to the field of natural geological disaster protection and early warning equipment. The landslide monitoring and early warning device has a high degree of automation and low cost. It is located below the ground and occupies a small space. It can automatically and accurately detect the expansion degree of the width of the mountain crack, which enhances the timeliness and accuracy of monitoring.

[0004] In the above patent, the degree of automation is high and the cost is low. It is located below the ground and occupies a small space. It can automatically and accurately detect the expansion of the width of mountain cracks, enhancing the timeliness and accuracy of monitoring. Before the early warning device works, it is necessary to install the early warning device and adjust the angle and height. The complicated installation method increases the working time of the staff and reduces work efficiency. Summary of the invention

[0005] In view of the deficiencies in the prior art, the present invention provides a monitoring and early warning device for cracks in a mine subsidence area, which solves the problems raised in the above-mentioned background technology.

[0006] To achieve the above objectives, the present invention is implemented through the following technical solutions: a monitoring and early warning device for cracks in a mine collapse area, comprising a mine car and a support frame, a laser transmitter is fixedly installed on the top of the mine car, a transmitting module, a detection module and a control module are arranged inside the laser transmitter, a signal transmitter is fixedly installed on the top of the mine car, a square groove is opened on the surface of the mine car, the control module is electrically connected to the signal transmitter, a measuring device is arranged on the top of the support frame, and a disassembly device, a protective device and an anti-mismeasurement device are arranged inside the mine car;

[0007] The disassembly device comprises a supporting leg, a telescopic leg, a limiting block, a deformation plate, a storage box, a hollow box, a triangular block, a supporting arc rod, a rotating plate, a square clamp and an unlocking rod, wherein the supporting leg is fixedly mounted on the bottom of the supporting frame, a positioning hole is opened on the surface of the supporting leg, the telescopic leg is slidably mounted on the inner wall of the supporting leg, an adjusting hole is opened on the surface of the telescopic leg, the limiting block is arranged on the surface of the supporting leg, the deformation plate is fixedly mounted on the surface of the limiting block, the storage box is arranged inside the square groove, the hollow box is fixedly mounted on the bottom of the inner wall of the storage box, the triangular block slides through the inner and outer walls of the hollow box, the supporting arc rod is fixedly mounted on the outer wall of the hollow box, the rotating plate is rotatably mounted on the circumferential surface of the supporting arc rod, the square clamp slides through the inner and outer walls of the hollow box, the square clamp is rotatably mounted on the top of the rotating plate, the unlocking rod slides through the top of the storage box, the triangular block moves to contact the rotating plate, the triangular block moves to push the rotating plate to rotate, the rotating plate rotates to drive the square clamp to move, and the square clamp moves to contact and limit the telescopic leg.

[0008] According to the above technical solution, a No. 1 spring is arranged between the deformation plates, the telescopic legs are in contact with the triangular block, and the deformation plates are driven to reset by the No. 1 spring.

[0009] According to the above technical solution, the square clamp is in contact with the telescopic leg, and a No. 1 spring is arranged between the rotating plate and the supporting arc rod, and the rotating plate is driven to reset by the No. 1 spring.

[0010] According to the above technical scheme, the protective device includes an L-shaped rotating rod, a baffle, a connecting piece, a rotating long rod and a stone turning plate. The L-shaped rotating rod is rotatably installed on the bottom of the inner wall of the storage box, the baffle is fixedly installed on the surface of the L-shaped rotating rod, the baffle arc surface is provided with a sliding groove, the connecting piece is slidably installed on the inner wall of the sliding groove, the interior of the square groove is provided with a square hole, the rotating long rod is rotatably installed on the inner wall of the square hole, the stone turning plate is slidably installed on the inner wall of the square hole, one end of the rotating long rod is rotatably installed on the surface of the connecting piece, and the other end of the rotating long rod is rotatably installed on the top of the stone turning plate. The rotation of the L-shaped rotating rod will drive the baffle to rotate, the rotation of the baffle will drive the connecting piece to slide on the inner wall of the sliding groove, the sliding of the connecting piece will drive the rotating long rod to rotate, and the rotation of the rotating long rod will drive the stone turning plate to slide.

[0011] According to the above technical solution, the protective device also includes a transmission rod, a ramp block and an arc-shaped clamp. The transmission rod is slidably installed on the bottom of the inner wall of the storage box, the ramp block is fixedly installed on the end of the transmission rod away from the triangular block, and the arc-shaped clamp is slidably installed on the inner bottom of the storage box. The rotation of the L-shaped rotating rod will drive the transmission rod to move, the movement of the transmission rod will drive the ramp block to move, the movement of the ramp block will push the arc-shaped clamp to move in the direction of the measuring device, and the movement of the arc clamp will clamp the measuring device.

[0012] According to the above technical solution, the triangular block contacts the L-shaped rotating rod, and a No. 2 spring is arranged between the L-shaped rotating rod and the storage box, and the No. 2 spring drives the L-shaped rotating rod to reset.

[0013] According to the above technical solution, the anti-misdetection device includes a V-shaped spring piece, a round rod, a limit rod, a standing foot, a return spring and a damping ball. The V-shaped spring piece is arranged between the storage box and the mine car, the round rod is rotatably installed at the bottom of the storage box, the limit rod is fixedly penetrated through the inside of the round rod, the standing foot is slidably installed inside the storage box, and the damping ball is connected to the inner wall of the standing foot through a return spring. The movement of the return spring will drive the damping ball to move. When mining is being carried out near the mine car or staff are walking nearby, the vibration generated will be offset by the damping ball and the return spring.

[0014] According to the above technical solution, a No. 2 spring is arranged between the standing foot and the storage box, the turning stone plate is in contact with the limiting rod, and the No. 2 spring drives the standing foot to reset.

[0015] The present invention provides a monitoring and early warning device for cracks in a mine subsidence area. It has the following beneficial effects:

[0016] (1) The invention limits the position of the telescopic legs and the supporting legs, so that the lengths of the supporting legs and the telescopic legs can be quickly adjusted. The operation is simple and the work difficulty is reduced. The telescopic legs are clamped by square clamps so that the telescopic legs can be fixed after the support frame is installed. This greatly reduces the installation time of the support frame, reduces the operation time of the staff, and improves work efficiency. The support frame can be disassembled by pressing the unlocking lever, further improving work efficiency.

[0017] (2) This invention uses a stone-turning plate to scrape the ground to prevent the measuring device from being damaged by the gravel on the surface when inserted into the ground, thereby improving the protection effect of the device and increasing the service life of the device. The measuring device is clamped by an arc-shaped clamp to prevent the measuring device from being affected and tilted when moving toward the bottom, resulting in early warning failure, thereby improving the stability of the device during operation.

[0018] (3) This invention supports the storage box through V-shaped springs and feet, so that when the mine car is hit or bumped, the storage box and the measuring device on the top will not be hit, and the measuring device will not be damaged due to the impact, thereby improving the protection of the device. The surrounding vibrations are offset by the damping ball and the return spring, preventing the measuring device from making erroneous measurements due to other reasons, thereby improving the accuracy of the device during measurement. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1It is a schematic diagram of the overall structure of the present invention;

[0020] Figure 2 This is a schematic diagram of the positional relationship between the laser transmitter and the signal transmitter of the present invention;

[0021] Figure 3 This is a schematic diagram of the position relationship structure of the limit block of the present invention;

[0022] Figure 4 This is a schematic diagram of the structure of the disassembly device of the present invention;

[0023] Figure 5 It is a schematic diagram of the cross-sectional structure of the hollow box of the present invention;

[0024] Figure 6 It is a schematic diagram of the structure of the protective device of the present invention;

[0025] Figure 7 It is a schematic diagram of the structure of the device for preventing misdetection of the present invention.

[0026] In the figure: 1. Mine car; 2. Laser transmitter; 3. Signal transmitter; 4. Measuring device; 51. Support frame; 52. Support leg; 53. Telescopic leg; 54. Limit block; 55. Deformation plate; 56. No. 1 spring; 57. Storage box; 58. Hollow box; 59. Triangular block; 510. Support arc rod; 511. Rotating plate; 512. Square clamp; 513. Unlocking rod; 61. L-shaped rotating rod; 62. Baffle; 63. Connecting piece; 64. Rotating long rod; 65. Turning stone board; 66. Transmission rod; 67. Inclined block; 68. Arc clamp; 71. V-shaped spring; 72. Round rod; 73. Limit rod; 74. Standing foot; 75. Reset spring; 76. Damping ball. DETAILED DESCRIPTION

[0027] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0028] See also Figure 1-Figure 7An embodiment of the present invention is: a monitoring and early warning device for cracks in a mine collapse area, comprising a mine car 1 and a support frame 51, a laser transmitter 2 is fixedly installed on the top of the mine car 1, a transmitting module, a detection module and a control module are arranged inside the laser transmitter 2, a signal transmitter 3 is fixedly installed on the top of the mine car 1, a square groove is provided on the surface of the mine car 1, the control module is electrically connected to the signal transmitter 3, a measuring device 4 is arranged on the top of the support frame 51, a disassembly device is arranged inside the mine car 1, the disassembly device comprises a support leg 52, a telescopic leg 53, a limit block 54, a deformation plate 55, a storage box 57, a hollow box 58, a triangular block 59, a support arc rod 510, a rotating plate 511, a square clamp 512, and an unlocking rod 513, the support leg 52 is fixedly installed at the bottom of the support frame 51, a positioning hole is provided on the surface of the support leg 52, the telescopic leg 53 is slidably installed on the inner wall of the support leg 52, and the telescopic leg 53 An adjustment hole is opened on the surface, and a limit block 54 is arranged on the surface of the supporting leg 52. The deformation plate 55 is fixedly installed on the surface of the limit block 54, so that the length of the supporting leg 52 and the telescopic leg 53 can be quickly adjusted, the operation is simple, and the working difficulty is reduced. The storage box 57 is arranged inside the square groove, and the hollow box 58 is fixedly installed on the bottom of the inner wall of the storage box 57. The triangular block 59 slides through the inner and outer walls of the hollow box 58, the supporting arc rod 510 is fixedly installed on the outer wall of the hollow box 58, and the rotating plate 511 is rotatably installed on the circumferential surface of the supporting arc rod 510. The square clamp 512 slides through the inner and outer walls of the hollow box 58, and the square clamp 512 is rotatably installed on the top of the rotating plate 511, which greatly reduces the installation time of the support frame 51, reduces the operation time of the staff, and improves the working efficiency. The unlocking rod 513 slides through the top of the storage box 57, so that the support frame 51 can be disassembled, further improving the working efficiency.

[0029] A No. 1 spring 56 is arranged between the deformation plates 55 , and the telescopic legs 53 are in contact with the triangular block 59 , and the deformation plates 55 are driven to reset by the No. 1 spring 56 .

[0030] The square clamp 512 is in contact with the telescopic leg 53 , and a No. 1 spring is provided between the rotating plate 511 and the supporting arc rod 510 , and the rotating plate 511 is driven to reset by the No. 1 spring.

[0031] When this embodiment is working: the telescopic leg 53 is pulled toward the bottom, and the movement of the telescopic leg 53 drives the adjustment hole to move. After being pulled to the required height, the deformation plate 55 is pressed, and the deformation plate 55 will be deformed after being squeezed. Then the limit block 54 is pushed toward the adjustment hole, and the movement of the limit block 54 drives the deformation plate 55 to move. After the deformation plate 55 completely passes through the adjustment hole, the deformation plate 55 is reset by the No. 1 spring 56. The reset of the deformation plate 55 limits the adjustment hole and the positioning hole, so that the length of the support leg 52 and the telescopic leg 53 can be quickly adjusted. The operation is simple and the work difficulty is reduced. The telescopic leg 53 is pressed in the direction of the hollow box 58. The telescopic leg 53 moves toward the bottom and contacts the triangular block 59. The movement of the telescopic leg 53 pushes the triangular block 59 to move away from the telescopic leg 53. The movement of the triangular block 59 contacts the rotating plate 511, the movement of the triangular block 59 will push the rotating plate 511 to rotate, and the rotation of the rotating plate 511 will drive the square clamp 512 to move, and the movement of the square clamp 512 will contact and limit the telescopic leg 53, so that the telescopic leg 53 can be fixed after the support frame 51 is installed, which greatly reduces the installation time of the support frame 51, reduces the operation time of the staff, and improves work efficiency. Press the unlocking rod 513 toward the bottom, and the unlocking rod 513 moves toward the bottom to contact the rotating plate 511. The movement of the unlocking rod 513 will push one end of the bottom of the rotating plate 511 to rotate toward the direction of the support leg 52. The rotation of the rotating plate 511 will drive the square clamp 512 to move away from the telescopic leg 53 and release the limit of the telescopic leg 53 by the square clamp 512, so that the support frame 51 can be disassembled, further improving work efficiency.

[0032] See also Figure 1-Figure 7 On the basis of the above embodiment, in another embodiment of the present invention, a protective device and an anti-misdetection device are arranged inside the mine car 1, wherein the protective device comprises an L-shaped rotating rod 61, a baffle 62, a connecting piece 63, a rotating long rod 64 and a stone turning plate 65, the L-shaped rotating rod 61 is rotatably mounted on the bottom of the inner wall of the storage box 57, the baffle 62 is fixedly mounted on the surface of the L-shaped rotating rod 61, a sliding groove is provided on the arc surface of the baffle 62, the connecting piece 63 is slidably mounted on the inner wall of the sliding groove, a square hole is provided inside the square groove, the rotating long rod 64 is rotatably mounted on the inner wall of the square hole, the stone turning plate 65 is slidably mounted on the inner wall of the square hole, one end of the rotating long rod 64 is rotatably mounted on the surface of the connecting piece 63, and the other end of the rotating long rod 64 is rotatably mounted on the top of the stone turning plate 65, and the sliding of the stone turning plate 65 will turn over the area at the bottom of the square hole, so that before the grounding area of ​​the measuring device 4 is inserted into the ground, the gravel on the surface will be scraped off by the stone turning plate 65, so as to prevent the measuring device 4 from being damaged by the gravel on the surface when being inserted into the ground, thereby improving the protection effect of the device.

[0033] The protective device also includes a transmission rod 66, a ramp block 67 and an arc clamp 68. The transmission rod 66 is slidably installed on the bottom of the inner wall of the storage box 57, the ramp block 67 is fixedly installed on the end of the transmission rod 66 away from the triangular block 59, and the arc clamp 68 is slidably installed on the inner bottom of the storage box 57 to prevent the measuring device 4 from being affected and tilted when moving toward the bottom, resulting in early warning failure, thereby improving the stability of the device during operation.

[0034] The triangular block 59 contacts the L-shaped rotating rod 61 . A second spring is arranged between the L-shaped rotating rod 61 and the storage box 57 . The second spring drives the L-shaped rotating rod 61 to reset.

[0035] The anti-mismeasurement device includes a V-shaped spring piece 71, a round rod 72, a limit rod 73, a standing foot 74, a reset spring 75 and a damping ball 76. The V-shaped spring piece 71 is arranged between the storage box 57 and the mining car 1, the round rod 72 is rotatably installed at the bottom of the storage box 57, the limit rod 73 is fixed and penetrates the inside of the round rod 72, and the standing foot 74 is slidably installed in the inside of the storage box 57. The measuring device 4 will not be damaged due to impact, thereby improving the protection of the device. The damping ball 76 is connected to the inner wall of the standing foot 74 through the reset spring 75 to prevent the measuring device 4 from making mismeasurements due to other reasons, thereby improving the accuracy of the device during measurement.

[0036] A No. 2 spring is provided between the standing foot 74 and the storage box 57, and the turning plate 65 contacts the limit rod 73, and the No. 2 spring drives the standing foot 74 to reset.

[0037] When the present embodiment is working, the triangular block 59 will contact the L-shaped rotating rod 61 when it moves away from the telescopic leg 53. The movement of the triangular block 59 will push the L-shaped rotating rod 61 to rotate. The rotation of the L-shaped rotating rod 61 will drive the baffle plate 62 to rotate. The rotation of the baffle plate 62 will drive the connecting member 63 to slide on the inner wall of the sliding groove. The sliding of the connecting member 63 will drive the rotating long rod 64 to rotate. The rotation of the rotating long rod 64 will drive the sliding of the stone flipping plate 65. The sliding of the stone flipping plate 65 will flip the area at the bottom of the square hole, so that the surface gravel of the grounded area of ​​the measuring device 4 will be scraped away by the stone flipping plate 65 before it is inserted into the ground, preventing The measuring device 4 is prevented from being damaged by the gravel on the surface when inserted into the ground, thereby improving the protection effect of the device and increasing the service life of the device. The L-shaped rotating rod 61 rotates to contact the transmission rod 66. The rotation of the L-shaped rotating rod 61 drives the transmission rod 66 to move. The movement of the transmission rod 66 drives the inclined block 67 to move. The movement of the inclined block 67 pushes the arc clamp 68 to move in the direction of the measuring device 4. The movement of the arc clamp 68 clamps the measuring device 4 to prevent the measuring device 4 from being affected and tilted when moving to the bottom, resulting in early warning failure, thereby improving the stability of the device during operation.

[0038] The movement of the stone flip plate 65 will contact the limit rod 73, and the movement of the stone flip plate 65 will push the limit rod 73 to rotate. After the limit rod 73 rotates, it will no longer contact the standing foot 74. After the limit rod 73 no longer contacts the standing foot 74, the standing foot 74 will be reset by the second spring and drive the standing foot 74 to move to the bottom. The standing foot 74 moves to the bottom and contacts the ground, and the storage box 57 and the mine car 1 are connected by the V-shaped spring piece 71, so that when the mine car 1 is hit and bumped, the storage box 57 and the measuring device 4 on the top will not be hit, and the measuring device 4 will not be damaged due to the impact, thereby improving the protection of the device. The movement of the standing foot 74 will drive the reset spring 75 to move, and the movement of the reset spring 75 will drive the damping ball 76 to move. When mining is being carried out near the mine car 1 or staff are walking nearby, the vibration generated will be offset by the damping ball 76 and the reset spring 75, so as to prevent the measuring device 4 from making mismeasurements due to other reasons, thereby improving the accuracy of the device during measurement.

[0039] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A monitoring and early warning device for cracks in a mine subsidence area, comprising a mine car (1) and a support frame (51), characterized in that: A laser transmitter (2) is fixedly mounted on the top of the mine car (1), a transmitter module, a detection module and a control module are arranged inside the laser transmitter (2), a signal transmitter (3) is fixedly mounted on the top of the mine car (1), a square groove is provided on the surface of the mine car (1), the control module is electrically connected to the signal transmitter (3), a measuring device (4) is arranged on the top of the support frame (51), and a disassembly device, a protection device and an anti-mismeasurement device are arranged inside the mine car (1); The disassembly device comprises a support leg (52), a telescopic leg (53), a limit block (54), a deformation plate (55), a storage box (57), a hollow box (58), a triangular block (59), a support arc rod (510), a rotating plate (511), a square clamp (512), and an unlocking rod (513); the support leg (52) is fixedly mounted on the bottom of the support frame (51); a positioning hole is provided on the surface of the support leg (52); the telescopic leg (53) is slidably mounted on the inner wall of the support leg (52); an adjustment hole is provided on the surface of the telescopic leg (53); the limit block (54) is arranged on the surface of the support leg (52); and the deformation plate (55) is arranged on the surface of the support leg (52). The storage box (57) is fixedly mounted on the surface of the limit block (54), the storage box (57) is arranged inside the square groove, the hollow box (58) is fixedly mounted on the bottom of the inner wall of the storage box (57), the triangular block (59) slides through the inner and outer walls of the hollow box (58), the supporting arc rod (510) is fixedly mounted on the outer wall of the hollow box (58), the rotating plate (511) is rotatably mounted on the circumferential surface of the supporting arc rod (510), the square clamp (512) slides through the inner and outer walls of the hollow box (58), the square clamp (512) is rotatably mounted on the top of the rotating plate (511), and the unlocking rod (513) slides through the top of the storage box (57).

2. A monitoring and early warning device for cracks in a mine subsidence area according to claim 1, characterized in that: A first spring (56) is provided between the deformation plates (55), and the telescopic legs (53) are in contact with the triangular block (59).

3. A monitoring and early warning device for cracks in a mine subsidence area according to claim 2, characterized in that: The square clamp (512) is in contact with the telescopic leg (53), and a first spring is provided between the rotating plate (511) and the supporting arc rod (510).

4. A monitoring and early warning device for cracks in a mine subsidence area according to claim 3, characterized in that: The protective device comprises an L-shaped rotating rod (61), a baffle plate (62), a connecting piece (63), a rotating long rod (64) and a stone turning plate (65), wherein the L-shaped rotating rod (61) is rotatably mounted on the bottom of the inner wall of the storage box (57), the baffle plate (62) is fixedly mounted on the surface of the L-shaped rotating rod (61), the baffle plate (62) has an arc surface with a sliding groove, the connecting piece (63) is slidably mounted on the inner wall of the sliding groove, a square hole is formed inside the square groove, the rotating long rod (64) is rotatably mounted on the inner wall of the square hole, the stone turning plate (65) is slidably mounted on the inner wall of the square hole, one end of the rotating long rod (64) is rotatably mounted on the surface of the connecting piece (63), and the other end of the rotating long rod (64) is rotatably mounted on the top of the stone turning plate (65).

5. A monitoring and early warning device for cracks in a mine subsidence area according to claim 4, characterized in that: The protective device further comprises a transmission rod (66), an inclined surface block (67) and an arc-shaped clamp (68); the transmission rod (66) is slidably mounted on the bottom of the inner wall of the storage box (57); the inclined surface block (67) is fixedly mounted on an end of the transmission rod (66) away from the triangular block (59); and the arc-shaped clamp (68) is slidably mounted on the inner bottom of the storage box (57).

6. A monitoring and early warning device for cracks in a mine subsidence area according to claim 5, characterized in that: The triangular block (59) is in contact with the L-shaped rotating rod (61), and a No. 2 spring is provided between the L-shaped rotating rod (61) and the storage box (57).

7. A monitoring and early warning device for cracks in a mine subsidence area according to claim 6, characterized in that: The anti-misdetection device comprises a V-shaped spring piece (71), a round rod (72), a limit rod (73), a standing foot (74), a return spring (75) and a damping ball (76); the V-shaped spring piece (71) is arranged between the storage box (57) and the mining car (1); the round rod (72) is rotatably mounted on the bottom of the storage box (57); the limit rod (73) is fixedly inserted into the inside of the round rod (72); the standing foot (74) is slidably mounted in the inside of the storage box (57); and the damping ball (76) is connected to the inner wall of the standing foot (74) via the return spring (75).

8. A monitoring and early warning device for cracks in a mine subsidence area according to claim 7, characterized in that: A No. 2 spring is provided between the standing foot (74) and the storage box (57), and the stone turning plate (65) is in contact with the limiting rod (73).

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