A goaf roof pressure monitoring device and a monitoring method thereof

Abstract

A goaf roof pressure monitoring device and a monitoring method thereof, which relate to the field of mine pressure monitoring, comprising a measuring unit, a fixing unit and a control unit, the measuring unit comprises a shell and a stepping motor capable of adjusting the pose thereof, the top of the shell comprises a horizontal center plate and a plurality of side inclined plates arranged around the edge thereof and facing the upper side outside the shell, the side inclined plates and the center plate are both provided with measuring ports with pressure sensors, the fixing unit comprises a plurality of anchor rods and locking pieces spirally arranged on the upper ends of the anchor rods, the stepping motor is a lead screw type stepping motor, a plurality of the stepping motors are vertically arranged along the edge of the shell, the output ends of the lead screws thereof are connected to one end of a transversely arranged connecting plate through a rolling bearing, the other end of the connecting plate is located outside the shell and is vertically provided with a positioning hole matched with the anchor rod, and the locking pieces can be matched with the anchor rods to lock the connecting plate in the reserved groove. The problems of data dimension loss, inability to level, cable damage and difficulty in maintaining the movable parts of the traditional device are solved.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of mine pressure monitoring, in particular to a goaf roof pressure monitoring device and a monitoring method thereof. BACKGROUND

[0002] Mine pressure monitoring is a key link of mining engineering, especially in goaf roof caving analysis, top cutting pressure relief effect evaluation and gob-side entry support design. Currently, traditional stress measurement methods (such as stress relief method and hydraulic fracturing method) have limitations such as inability to monitor long-term, inability to cover caving rock area, etc.

[0003] The prior art such as patent CN110748382B, a stress monitoring method and device for goaf, can monitor the pressure in the goaf, but has the following problems:

[0004] 1. The measuring device only collects the vertical pressure generated by the roof caving through a single vertically arranged stress monitoring device, and cannot synchronously obtain horizontal extrusion stress or oblique shear stress data. This single-dimensional monitoring mode leads to the lack of key data in the analysis of roof caving rock movement rules, making it difficult to accurately judge the stability of the short-wall beam structure after top cutting pressure relief.

[0005] 2. The measuring device relies on the forced synchronous movement of the four hydraulic cylinders through the equalizing pipe to maintain the horizontal bearing plate, but the installation of the installation plate cannot guarantee the horizontal, and the equalizing pipe cannot actively correct the inclination of the bearing plate, which makes it difficult for the stress monitoring device to be horizontal, and further leads to monitoring data errors.

[0006] 3. The stress monitoring device is connected to the monitoring substation through independent data lines, which need to be hung on the cable hook on one side of the coal mining equipment and moved with the equipment. When multiple measuring devices need to be densely arranged in the working face, it will lead to the interlaced winding of multiple data lines, which is easy to be damaged by extrusion, and the troubleshooting is difficult. Moreover, the length of each measuring device needs to be controlled separately, which significantly increases the operation burden.

[0007] 4. The four hydraulic cylinders of the measuring device are exposed and connected to the hydraulic pump without any protection, which is easy to be damaged. The hydraulic cylinder and its connecting pipeline are completely exposed to the harsh environment of the goaf, lack of protection structure, and the flying gangue in the roof caving process is easy to damage the hydraulic cylinder seal or pipeline, leading to the failure of the hydraulic system and seriously reducing the long-term reliability of the measuring device. SUMMARY

[0008] To solve the technical problems of the measuring device in the background art that cannot synchronously obtain horizontal extrusion stress or oblique shear stress data and the stress monitoring device that is difficult to be horizontal, the present application provides a goaf roof pressure monitoring device and a monitoring method thereof.

[0009] The technical scheme of the present application is as follows:

[0010] A goaf roof pressure monitoring device, comprising a measuring unit and a fixing unit capable of being fixed in a reserved groove, and a control unit electrically connected with the measuring unit.

[0011] As the core technical concept of the present application, the measuring unit comprises a shell and a stepping motor capable of adjusting the pose thereof, the shell comprises an upper shell and a lower shell, the upper shell comprises a horizontal center plate and a plurality of side inclined plates arranged around the edge thereof and facing upward outside the shell, and the side inclined plates and the center plate are both provided with measuring openings with pressure sensors.

[0012] Further, the fixing unit comprises a plurality of anchor rods and locking members spirally arranged on the upper ends of the anchor rods, the stepping motor is a screw stepping motor, a plurality of the screw stepping motors are vertically arranged along the edge of the shell, the output ends of the screw stepping motors are arranged downward, and the output ends are connected with the anchor rods through connecting plates, the connecting plates are horizontally arranged, one end of each connecting plate is rotatably connected with the output end of the screw stepping motor through a rolling bearing, and the other end of each connecting plate is located outside the shell and is vertically provided with a positioning hole matched with the anchor rod, the locking members can be matched with the anchor rods to lock the connecting plates in the reserved groove, and a gyroscope sensor in communication connection with the stepping motor is further arranged in the shell.

[0013] As a preferred embodiment, the stepping motor and the gyroscope sensor are both arranged inside the shell, a cable sheath is further arranged on one side of the shell, and the signal lines and power lines of the pressure sensors, the gyroscope sensor and the stepping motor are sequentially led out to the cable sheath along the inside of the shell.

[0014] The arrangement of the stepping motor and the gyroscope sensor inside the shell improves the service life of the stepping motor and the gyroscope sensor, and through the arrangement of the cable sheath, the signal lines and the power lines can be effectively prevented from being damaged by extrusion or being intertwined with soil and stones, which is beneficial to fault diagnosis and convenient for operation.

[0015] As a preferred embodiment, the detection surface of the pressure sensor penetrates through the measuring opening and is flush with the outer surface of the center plate or the side inclined plate corresponding thereto, and the upper shell is a hollow quadrangular prism structure.

[0016] Further, a plurality of support plates are arranged inside the upper shell and are respectively arranged parallel to the lower side of the center plate and the four side inclined plates, each pressure sensor is mounted on the support plate corresponding to the center plate or the side inclined plate, and the gyroscope sensor is mounted on the lower side of the support plate corresponding to the center plate.

[0017] Preferably, the shell is a steel shell, and the pressure sensors and the gyroscope sensor are both mounted on the support plates through metal glue.

[0018] In order to further protect the signal lines and the power lines, a plastic hose is sleeved outside the cable sheath, and the cable sheath is arranged in a snake shape in the plastic hose.

[0019] As a preferred embodiment, the lower shell is a rectangular box structure, four stepping motors are arranged at four corners inside the lower shell, and the output ends of the leadscrews of the stepping motors are connected with the connecting plates through the lower shell.

[0020] The application also provides a monitoring method using the goaf roof pressure monitoring device.

[0021] S1: excavating a reserved groove in the floor stratum;

[0022] S2, pre-fixing the measuring unit in the reserved groove;

[0023] Specifically,

[0024] S2.1, placing the measuring unit in the pre-installation position in the reserved groove;

[0025] S2.2, anchoring the anchor rods of the fixing unit in the reserved groove through the positioning holes in the connecting plates;

[0026] S2.3, installing the locking pieces on the upper ends of the anchor rods, and pre-locking the corresponding connecting plates at the bottom of the reserved groove;

[0027] S3, collecting the gyroscope sensor data in real time, controlling the corresponding stepping motor to level the measuring unit, and then adjusting the locking pieces to lock the connecting plates in the reserved groove;

[0028] S4, filling the reserved groove around the measuring unit with buffer materials;

[0029] S5, laying steel plates above the reserved grooves on both sides of the measuring unit;

[0030] S6, collecting the pressure sensor data in real time, and analyzing the vertical and horizontal pressure distribution of the roof stratum.

[0031] The application has the following beneficial effects compared with the prior art:

[0032] 1. Through the special design of the upper shell structure and the combination with the pressure sensor, the synchronous monitoring of the vertical and horizontal pressures is realized, and the multiple side inclined plates are distributed around, covering different directions, and filling the key data missing in the analysis of the roof collapse stratum movement law;

[0033] 2. Through the closed-loop control system of the stepping motor and the gyroscope sensor, and the cooperative leveling mechanism of the fixing unit and the stepping motor, the shell is easy to adjust and keep horizontal, thereby improving the accuracy of the monitoring data;

[0034] 3、Through the setting of the cable sheath, the signal lines and the power lines can be effectively prevented from being exposed and damaged by extrusion or being intertwined with soil and stones, which is beneficial to the troubleshooting of the lines and the wiring operation;

[0035] 4、The stepper motor and the gyroscope sensor are arranged in the interior of the shell, the service life of the stepper motor and the gyroscope sensor is improved, and the long-term reliability of the measuring unit is improved. BRIEF DESCRIPTION OF DRAWINGS

[0036] In the drawings:

[0037] Figure 1 It is a structure schematic view of a goaf roof pressure monitoring device installed in a reserved trench in the embodiment;

[0038] Figure 2 It is an internal structure schematic view of a goaf roof pressure monitoring device in the embodiment;

[0039] Figure 3 It is a use schematic view of a goaf roof pressure monitoring device in the embodiment;

[0040] Figure 4 It is Figure 3 It is a top view of a goaf roof pressure monitoring device in the embodiment (hiding the coal mining equipment, rotating 90° to the right);

[0041] The components represented by the reference numerals in the drawings are as follows:

[0042] 1, reserved trench; 2, coal mining equipment; 21, scraper conveyor; 22, coal cutter; 23, fully mechanized support; 3, measuring unit; 31, shell; 311, center plate; 312, side inclined plate; 313, support plate; 32, adjusting mechanism; 321, stepper motor; 322, gyroscope sensor; 33, pressure sensor; 34, connecting plate; 35, cable sheath; 36, plastic hose; 37, thickened bottom plate; 4, fixing unit; 41, anchor rod; 42, locking nut; 5, steel plate; 6, buffer material; 7, anchoring agent. DETAILED DESCRIPTION

[0043] Exemplary embodiments of the present disclosure will be described in greater detail below with reference to the accompanying drawings.

[0044] EMBODIMENT

[0045] In combination with Figure 1 and Figure 2 , the embodiment provides a goaf roof pressure monitoring device, which comprises a measuring unit 3, a fixing unit 4 capable of fixing the measuring unit 3 in a reserved trench 1 of a bottom stratum, and a control unit electrically connected with the measuring unit 3.

[0046] Specifically, the measuring unit 3 comprises a shell 31 and an adjusting mechanism 32 inside the shell 31, the adjusting mechanism 32 comprises a stepping motor 321 capable of adjusting the pose of the shell 31, and the shell 31 comprises an upper shell and a lower shell, the upper shell comprises a center plate 311 arranged horizontally and a plurality of side inclined plates 312 arranged around the edge of the center plate 311 and facing the upper side outside the shell 31.

[0047] The side inclined plate 312 and the center plate 311 are both provided with measuring ports, and a pressure sensor 33 is further arranged corresponding to each measuring port, and the detection surface of the pressure sensor 33 passes through the measuring port and is flush with the outer surface of the corresponding center plate 311 or side inclined plate 312.

[0048] The center plate 311 measures the vertical pressure, and the side inclined plate 312 can decompose the horizontal pressure component of the roof collapse rock layer through the inclination angle (such as 45 degrees), realizing the synchronous monitoring of vertical and horizontal pressure, and the plurality of side inclined plates 312 are distributed around and cover different directions, filling the key data missing in the analysis of the movement law of the roof collapse rock layer.

[0049] In combination Figure 2 The upper shell is a hollow quadrangular prism structure.

[0050] The upper shell is further provided with a plurality of support plates 313 arranged in parallel below the center plate 311 and the four side inclined plates 312, and each pressure sensor 33 is installed on the corresponding support plate 313 of the center plate 311 or the side inclined plate 312.

[0051] In combination Figure 1 The fixing unit 4 comprises a plurality of anchor rods 41 and locking members spirally arranged on the upper ends of the anchor rods 41, the stepping motor 321 is a lead screw type stepping motor, a plurality of which are vertically arranged along the edge of the shell 31, and the output end of the lead screw of each stepping motor 321 is arranged downward and connected with the anchor rod 41 through a connecting plate 34.

[0052] The connecting plate 34 is transversely arranged, one end of which is rotatably connected with the output end of the lead screw of the stepping motor 321 through a rolling bearing, and the other end is located outside the shell 31 and is vertically provided with a positioning hole in clearance fit with the anchor rod 41, and the locking member can lock the connecting plate 34 in the reserved groove 1 in cooperation with the anchor rod 41, and the adjusting mechanism 32 further comprises a gyroscope sensor 322 arranged in the shell 31 and in communication connection with the stepping motor 321.

[0053] In order to reduce the thickness of the connecting plate 34 while meeting the use strength of the connecting plate 34, a thickened bottom plate 37 is fixedly connected to one end of the connecting plate 34 connected with the stepping motor 321, and the output end of the lead screw of the stepping motor 321 is rotatably connected with the thickened bottom plate 37 through a rolling bearing.

[0054] The locking member is a locking nut 42, during installation, the locking nut 42 is screwed to pre-fix the connecting plate 34 in the reserved groove 1, and the levelness of the shell 31 is monitored by the gyroscope sensor 322, the step motor 321 is controlled to adjust the pose of the shell 31, until the leveling of the shell 31 is completed and the locking nut 42 locks the connecting plate 34 in the reserved groove 1, so that the data deviation problem caused by the installation inclination of the traditional device is solved.

[0055] The step motor 321 and the gyroscope sensor 322 are arranged in the shell 31, and the shell 31 is further provided with a cable sheath 35, the signal lines and power lines of the pressure sensor 33, the gyroscope sensor 322 and the step motor 321 are arranged along the inside of the shell 31 to the cable sheath 35.

[0056] Specifically Figure 2 , the lower shell is a rectangular box structure, and the top surface of the lower shell coincides with the bottom surface of the upper shell.

[0057] The gyroscope sensor 322 is installed on the lower side of the support plate 313 corresponding to the center plate 311.

[0058] The step motor 321 is arranged on four corners of the inside of the lower shell, and the lead screw output end thereof is connected with the connecting plate 34 through the lower shell.

[0059] The shell 31 is a steel shell 31, and the pressure sensor 33 and the gyroscope sensor 322 are mounted on the support plate 313 through metal glue.

[0060] The arrangement of the step motor 321 and the gyroscope sensor 322 in the shell 31 improves the service life of the step motor 321 and the gyroscope sensor 322, and through the arrangement of the cable sheath 35, the signal lines and power lines can be effectively prevented from being damaged by extrusion or being intertwined with soil and stones, which is beneficial to fault diagnosis and operation.

[0061] In this embodiment, the cable sheath 35 includes a polyvinyl chloride protective layer and a steel belt armored protective layer arranged from inside to outside, and an insulating filler arranged between the polyvinyl chloride protective layer and the signal lines and power lines.

[0062] In combination Figure 4 , the cable sheath 35 is further sleeved with a plastic hose 36, and the double-layer protection of the cable sheath 35 and the plastic hose 36 improves the impact resistance of the signal lines and power lines to the falling of the roof and stones, and improves the service life.

[0063] The cable sheath 35 is arranged in a snake shape in the plastic hose 36 to reserve the length of the signal lines or power lines, so as to avoid the deformation of the rock stratum and the breakage of the signal lines or power lines.

[0064] In combination Figure 3 The application also provides a monitoring method using the goaf roof pressure monitoring device.

[0065] S1: excavating a reserved groove 1 in the floor stratum;

[0066] Specifically, a coal cutter 22 of the coal mining equipment 2 can be used to cut a reserved groove 1 in the floor stratum of the working face at a pre-installation position, and the reserved groove 1 is arranged in a direction away from the coal mining advancing direction of the coal mining equipment 2, and preferably, the reserved groove 1 is arranged in a direction perpendicular to the coal mining advancing direction of the coal mining equipment 2;

[0067] In some cases, after the reserved groove 1 is excavated, a shovel or other tools are used to clean up the gravel or sand at the bottom of the reserved groove 1, and the shovel is used to roughly arrange and level the bottom of the reserved groove 1;

[0068] S2, pre-fixing the measuring unit 3 in the reserved groove 1;

[0069] Specifically:

[0070] S2.1, placing the measuring unit 3 horizontally in the pre-installation position in the reserved groove 1;

[0071] S2.2, anchoring each anchor rod 41 of the fixing unit 4 in the reserved groove 1 through the positioning hole on each connecting plate 34;

[0072] S2.3, installing a locking piece on the upper end of each anchor rod 41 to pre-lock the corresponding connecting plate 34 at the bottom of the reserved groove 1;

[0073] S3, collecting data of the gyroscope sensor 322 in real time, controlling the corresponding stepping motor 321 to level the measuring unit 3, and then adjusting the locking piece to lock the connecting plate 34 in the reserved groove 1;

[0074] S4, filling the reserved groove 1 around the measuring unit 3 with buffer material 6;

[0075] The buffer material 6 includes gravel, fine sand or soil, and after filling, compaction is performed, and attention should be paid to not disturbing the monitoring device during compaction;

[0076] S5, laying the steel plate 5 above the reserved groove 1 on both sides of the measuring unit 3;

[0077] Specifically, the steel plate 5 is laid above the reserved groove 1 on both sides of the measuring unit 3 corresponding to the position of the arch support 23 of the coal mining equipment 2 to assist the scraper conveyor 21 and the fully mechanized support 23 to pass through the reserved groove 1 position, and attention should be paid to avoiding the position directly above the monitoring device when laying the steel plate 5;

[0078] S6, real-time acquisition of each pressure sensor 33 data, analysis of the roof strata vertical and horizontal pressure distribution.

[0079] In step 4, before filling the reserved trench 1 around the measuring unit 3 with the buffer material 6, the signal lines and power lines in the shell 31 are led out to the cable sheath 35 along the inside of the shell 31, while the plastic hose 36 is sleeved outside the cable sheath 35, and the cable sheath 35 is arranged in a zigzag manner inside the plastic hose 36, and then connected to the downhole ring network.

[0080] In some cases, the adjustment range of the stepper motor 321 in step 3 may not be sufficient to cover the inclination of the measuring unit 3. Based on this, step 2.2 specifically includes:

[0081] Step S2.2.1: After placing the measuring unit 3 horizontally in the pre-installed position in the reserved trench 1, the initial inclination angle of the measuring unit 3 is acquired by the gyroscope sensor 322, and the initial inclination angle is compared with the preset angle;

[0082] If the initial inclination angle is greater than the preset angle, the corresponding anchor rod 41 is drilled in the opposite direction of the initial inclination angle by a preset angle through the positioning hole on the connecting plate 34, and the anchor rod 41 is anchored in the drilled hole;

[0083] Step S2.2.2: If the initial inclination angle is less than or equal to the preset angle, the anchor rod 41 is drilled and anchored in the vertical direction through the positioning hole on the connecting plate 34;

[0084] Wherein, the preset angle is determined by the following way:

[0085] According to the lead screw stroke of each stepper motor 321 and the spacing between each anchor rod 41, the maximum inclination angle that the measuring unit 3 can be leveled is calculated, and the maximum inclination angle plus 5° is taken as the preset angle.

[0086] For example, the initial inclination angle of the measuring unit 3 is 12°, and the preset angle is 10° (determined by the maximum leveling angle 5° plus 5°). Step S2.2.1 is executed: the anchor rod 41 is installed by tilting 10° in the opposite direction (e.g. tilting left, then drilling right), so that the stepper motor 321 only needs to adjust the remaining 2° inclination subsequently.

[0087] For example, the initial inclination angle of the measuring unit 3 is 8°, and the preset angle is 10°. Step S2.2.2 is executed: the anchor rod 41 is directly anchored vertically (e.g. Figure 1 The anchor rod 41 shown), and the subsequent stepper motor 321 can fully cover the leveling needs of the measuring unit 3.

[0088] Wherein the anchor rod 41 is filled with anchor agent 7 in the hole drilled, and preferably the resin anchor agent 7, the fluidity and curing strength of the resin anchor agent 7 can adapt to the inclined drill hole, and the drill hole depth is not less than 1 meter, to ensure the pull-out resistance of the anchor rod 41.

Claims

1. A monitoring method of a goaf roof pressure monitoring device, characterized in that: The monitoring device used comprises a measuring unit (3) and a fixing unit (4) capable of being fixed in a reserved groove (1), and a control unit electrically connected with the measuring unit (3); The measuring unit (3) comprises a shell (31) and a stepping motor (321) capable of adjusting the pose thereof; The shell (31) comprises an upper shell and a lower shell, the upper shell comprises a horizontal center plate (311) and a plurality of side inclined plates (312) arranged around the edge thereof and facing upward outside the shell (31), and the side inclined plates (312) and the center plate (311) are both provided with measuring ports with pressure sensors (33); The fixing unit (4) comprises a plurality of anchor rods (41) and locking members spirally arranged on the upper ends of the anchor rods (41), the stepping motor (321) is a screw stepping motor, a plurality of the stepping motors are vertically arranged along the edge of the shell (31), the screw output ends of the stepping motors are arranged downward, and the anchor rods (41) are connected with the screw output ends of the stepping motors through connecting plates (34), the connecting plates (34) are transversely arranged, one end of each connecting plate (34) is rotatably connected with the screw output end of the corresponding stepping motor (321) through a rolling bearing, the other end of each connecting plate (34) is located outside the shell (31) and is vertically provided with a positioning hole for gap-fitting with the corresponding anchor rod (41), and the locking members can lock the connecting plates (34) in the reserved groove (1) by fitting with the anchor rods (41); The shell (31) is further provided with a gyroscope sensor (322) in communication connection with the stepping motor (321); The monitoring method comprises the following steps: S1, excavating a reserved groove (1) in a floor rock stratum; S2, pre-fixing the measuring unit (3) in the reserved groove (1); Specifically: S2.1, placing the measuring unit (3) on a pre-installation position in the reserved groove (1); S2.2, anchoring each anchor rod (41) of the fixing unit (4) in the reserved groove (1) through the positioning hole on each connecting plate (34); S2.2.1, after placing the measuring unit on the pre-installation position in the reserved groove, collecting the initial inclination angle of the measuring unit by the gyroscope sensor, and comparing the initial inclination angle with a preset angle; If the initial inclination angle is greater than the preset angle, drilling a hole in the opposite direction of the initial inclination angle by a preset angle through the positioning hole on the connecting plate corresponding to the anchor rod, and anchoring the anchor rod in the drilled hole; S2.2.2, if the initial inclination angle is less than or equal to the preset angle, drilling a hole in the vertical direction through the positioning hole on the connecting plate and anchoring the anchor rod; Wherein, the preset angle is determined by the following method: according to the stroke of each stepping motor and the spacing between the anchor rods, calculating the maximum inclination angle at which the measuring unit can be leveled, and adding 5° to the maximum inclination angle as the preset angle; S2.3, installing the locking member on the upper end of each anchor rod (41) to pre-lock the corresponding connecting plate (34) at the bottom of the reserved groove (1); S3, collecting the data of the gyroscope sensor (322) in real time, controlling the corresponding stepping motor (321) to level the measuring unit (3), and then adjusting the locking member to lock the connecting plate (34) in the reserved groove (1). S4, fill the reserved groove (1) around the measuring unit (3) with buffer material (6); S5, lay steel plate (5) above the reserved groove (1) on both sides of the measuring unit (3); S6, collect data of each pressure sensor (33) in real time, and analyze vertical and horizontal pressure distribution of the roof stratum.

2. The monitoring method of a goaf roof pressure monitoring device according to claim 1, characterized in that, The stepping motor (321) and the gyroscope sensor (322) are arranged inside the shell (31), and the shell (31) is further provided with a cable sheath (35) on one side; The signal lines and power lines of the pressure sensor (33), the gyroscope sensor (322) and the stepping motor (321) are sequentially arranged from inside the shell (31) to the cable sheath (35).

3. The monitoring method of a goaf roof pressure monitoring device according to claim 1, characterized in that, The detection surface of the pressure sensor (33) passes through the measuring port and is flush with the outer surface of the corresponding central plate (311) or side inclined plate (312).

4. The monitoring method of a goaf roof pressure monitoring device according to claim 1, characterized in that, The upper shell is a hollow quadrangular frustum structure.

5. The monitoring method of a goaf roof pressure monitoring device according to claim 4, characterized in that, The upper shell is further provided with a plurality of support plates (313) arranged in parallel below the central plate (311) and the four side inclined plates (312). Each pressure sensor (33) is mounted on the corresponding support plate (313) of the central plate (311) or the side inclined plate (312).

6. A monitoring method of a goaf roof pressure monitoring device according to claim 5, characterized in that, The gyroscope sensor (322) is mounted below the corresponding support plate (313) of the central plate (311).

7. A monitoring method of a goaf roof pressure monitoring device according to claim 6, characterized in that, The shell (31) is a steel shell, and the pressure sensor (33) and the gyroscope sensor (322) are both mounted on the support plate (313) by metal glue.

8. The monitoring method of a goaf roof pressure monitoring device according to claim 2, characterized in that, The cable sheath (35) is further provided with a plastic hose (36) outside, and the cable sheath (35) is arranged in a serpentine shape in the plastic hose (36).

9. The monitoring method of a goaf roof pressure monitoring device according to claim 2, characterized in that, The lower shell is a rectangular box structure, and the stepping motor (321) is arranged at four corners inside the lower shell. The output end of the screw rod of the stepping motor (321) passes through the lower shell and is connected with the connecting plate (34).

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