Drilling rig for detecting fault stress field of deep coal seam in mining area

Abstract

The invention relates to the technical field of coal seam drilling, and discloses a drilling rig for detecting a fault stress field of a deep coal seam in a mining area, the drilling rig comprises a support base, the top end of the support base is provided with a main shaft motor, and the output end of the main shaft motor is connected with a flange plate; the top end of the flange plate is connected with a drilling assembly, the drilling assembly comprises a drilling rod, and the front end of the drilling rod is connected with an extension rod. According to the drilling rig for detecting the fault stress field of the deep coal seam in the mining area, slag can be temporarily stored in the cavity formed after the drilling head and the drilling rod are separated, the slag can be efficiently raised and discharged through the slag discharging groove under the action of slow rotation of the drilling rod in cooperation with air blown by the air pump through the air holes, the hidden danger of blockage caused by traditional single-channel slag discharging is thoroughly avoided, and the working efficiency is improved. The deslagging efficiency is greatly improved, and meanwhile, the gas accumulation risk is reduced. The occurrence rate of hole blockage, drill jamming and safety accidents is remarkably reduced, and reliable technical support is provided for safe and efficient mining of deep coal mines.

Description

Technical Field

[0001] The present invention relates to the technical field of coal seam drilling, and in particular to a drilling device for detecting a fault stress field of a deep coal seam in a mining area. Background Art

[0002] Coal seam drilling equipment is primarily used to accurately detect stress distribution within coal seam fault zones, providing key geological parameters for gas prevention and control, fault stability assessment, and safe production in deep coal mining. This equipment typically integrates a drilling system, stress monitoring module, slag removal mechanism, and cooling components. It uses directional drilling technology to penetrate deep into coal seam fault zones and inverts stress field characteristics based on real-time monitoring data. Its performance directly impacts the accuracy of fault structure identification and the safety of drilling operations.

[0003] In deep coal mine drilling operations, slag removal efficiency and drilling stability remain key issues limiting construction safety and efficiency. Existing drilling rigs often feature integrated drill bits, making the slag removal channel susceptible to clogging by coal and rock slag. This is particularly true in interbedded strata where hard rock and coal seams intersect, where the slag has an uneven particle size and is highly viscous. The single slag removal path of traditional drill bits often leads to hole blockage and drill bit jamming due to flow fluctuations. This not only requires frequent downtime for cleaning, reducing drilling efficiency, but also can cause frictional heating due to slag retention, increasing the risk of gas accumulation and fire. Summary of the Invention

[0004] The technical problem to be solved by the present invention is that the existing technology has the disadvantage of slag blockage in the drill bit. For this reason, we propose a drilling device for detecting the fault stress field of deep coal seams in mining areas.

[0005] To achieve the above-mentioned purpose, the present application adopts the following technical solution: a drilling device for detecting the fault stress field of a deep coal seam in a mining area, comprising a support base, a spindle motor is mounted on the top of the support base, and a flange is connected to the output end of the spindle motor; The top of the flange is connected to a drilling assembly, which includes a drilling rod, the front end of the drilling rod is connected to an extension rod, the top of the extension rod is connected to a drilling probe, the surface of the drilling probe is provided with a spiral groove, the end of the drilling probe is connected to an isolation cover, the outer surfaces of the drilling rod and the extension rod are sleeved with the drill rod, the surface of the drill rod is provided with an isolation cover, the outer surface of the drill rod is connected with a collar and a transmission sleeve, the outer surface of the transmission sleeve is sleeved with a transmission belt, a driving wheel is installed on the inner side of the transmission belt, a transmission motor is installed on the support base, the output end of the transmission motor is connected to the driving wheel, the transmission motor drives the transmission sleeve and the drill rod to rotate, and a hydraulic rod is also installed on the support base, the output end of the hydraulic rod is connected with a collar, the collar and the drill rod are rotatably connected, and the hydraulic rod drives the collar and the drill rod to move back and forth.

[0006] Preferably, a propulsion assembly is installed on the inner side of the support base, and the propulsion assembly includes a propulsion motor. The output end of the propulsion motor is connected to a threaded rod, and the bottom end of the support base is connected to a sliding rod.

[0007] Preferably, the propulsion motor drives the threaded rod to rotate, and the spindle motor moves horizontally along the guide rail on the support base under the transmission of the threaded rod.

[0008] Preferably, an extension rod is fixedly connected to the top end of the drilling rod, air holes are opened on the surface of the extension rod, the interior of the drilling rod and the extension rod are set as a hollow structure, one end of the drilling rod is connected to an air pump, and the air blown by the air pump is transported from the drilling rod to the interior of the extension rod.

[0009] Preferably, the drilling rod and the drill bit are movably connected, the transmission motor drives the driving wheel and the transmission belt to drive the transmission sleeve to rotate, the rotation of the transmission sleeve drives the drill rod to rotate, and the rotation of the drill rod and the rotation of the drill head are used for drilling the coal seam.

[0010] Preferably, the movable connection between the drill rod and the drilling rod is used for sliding back and forth between the drill rod and the drill rod, and for the drill rod to rotate on the surface of the drilling rod.

[0011] Preferably, the drilling head is configured to be conical, and the surface is provided with stepped protrusions.

[0012] Preferably, the end of the spiral groove on the surface of the drilling head corresponds to the notch on the isolation cover, and the debris generated by drilling with the drilling head is guided by the spiral groove through the notch on the isolation cover and falls to one side of the isolation cover.

[0013] Preferably, a groove is provided on the side of the isolation cover facing away from the drilling probe, and the groove wall is configured to be arc-shaped, and the arc-shaped groove wall is used to guide the air blown in by the air pump.

[0014] Preferably, during the initial drilling, the drill head and the drill rod are tightly fitted, and the drill head and the drill rod rotate simultaneously until the drill rod is embedded in the inner wall of the rock formation. Thereafter, the drill head accelerates and the drill rod rotates slowly, and the drill head and the drill rod are separated. The air hole separating the drill head and the drill rod slides out from the inside of the drill rod, and the air blown by the air pump is blown out from the inside of the air hole.

[0015] Technical effects and advantages of the present invention: The present invention uses a segmented drill bit structure to specifically address the problems of poor slag discharge, drill bit overheating, and insufficient drilling stability in the prior art. On the one hand, the cavity formed after the drill head and drill rod are separated can temporarily store slag. Combined with the air pump blowing in through the air holes, the air can efficiently lift the slag and discharge it through the slag discharge trough under the action of the slow rotation of the drill rod, completely avoiding the potential blockage risk of traditional single-channel slag discharge and significantly improving slag discharge efficiency. On the other hand, air circulation can directly cool the high-speed rotating drill head, reducing overheating losses and the risk of gas accumulation. Furthermore, the stable support after the drill rod is embedded in the rock formation and the precise spacing control of the hydraulic rod, combined with the speed adjustment of the independent dual-motor drive, effectively improve the stability of the drilling process, reduce drilling trajectory deviation, and ensure the accuracy of deep coal seam fault stress field detection data. This significantly reduces the incidence of hole blockage, drill sticking, and safety accidents, providing reliable technical support for safe and efficient mining in deep coal mines. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The disclosure of the present invention is illustrated with reference to the accompanying drawings. It should be understood that the drawings are for illustrative purposes only and are not intended to limit the scope of protection of the present invention. In the drawings, the same reference numerals are used to refer to the same components: Figure 1 It is a schematic diagram of the three-dimensional structure of the present invention; Figure 2 This is a schematic structural diagram of the propulsion motor and threaded rod of the present invention; Figure 3 It is a structural schematic diagram of the transmission belt and transmission motor of the present invention; Figure 4 It is a schematic diagram of the top view of the structure of the present invention; Figure 5 It is a structural schematic diagram of the transmission sleeve and the driving wheel of the present invention; Figure 6 This is a structural diagram of the drill rod and slag discharge trough of the present invention; Figure 7 This is a schematic structural diagram of the slag discharge chute and isolation cover of the present invention; Figure 8 This is a schematic structural diagram of the isolation cover and the extension rod of the present invention; Figure 9 This is a structural diagram of the present invention when the drilling probe and the drill rod are separated.

[0017] Legend: 11. Support base; 12. Spindle motor; 13. Flange; 2. Propulsion assembly; 21. Propulsion motor; 22. Threaded rod; 23. Sliding rod; 3. Drilling assembly; 31. Drilling rod; 32. Drill head; 33. Spiral groove; 34. Drill rod; 35. Slag discharge chute; 36. Isolation cover; 4. Drive assembly; 41. Transmission sleeve; 42. Driving wheel; 43. Transmission belt; 44. Transmission motor; 45. Ring; 46. Hydraulic rod; 47. Extension rod; 48. Air hole. DETAILED DESCRIPTION

[0018] It is easy to understand that according to the technical solution of the present invention, without changing the essential spirit of the present invention, a person skilled in the art can propose a variety of interchangeable structural modes and implementation modes. Therefore, the following specific embodiments and drawings are only exemplary descriptions of the technical solution of the present invention and should not be regarded as the entire invention or as a limitation or restriction of the technical solution of the present invention.

[0019] Reference Figure 1-9 As shown, the present invention provides a technical solution: When detecting fault stress fields in deep coal seams in mining areas, the drilling rig's slag removal efficiency, operational stability, and drill bit heat dissipation performance are directly related to the accuracy of detection data and operational safety. Currently, existing drilling rigs, due to rigid slag removal system designs and monotonous drill bit structures, often face challenges such as slag blockage, easy drilling deviation, and drill bit overheating. These issues severely restrict detection effectiveness in complex deep geological conditions and make it difficult to meet the demands of efficient and safe operations. Based on this, a drilling device for detecting fault stress fields in deep coal seams in mining areas is proposed, comprising a support base 11, a spindle motor 12 is mounted on the top of the support base 11, and a flange 13 is connected to the output end of the spindle motor 12; A propulsion assembly 2 is installed on the inner side of the support base 11. The propulsion assembly 2 includes a propulsion motor 21. The output end of the propulsion motor 21 is connected to a threaded rod 22. The bottom end of the support base 11 is connected to a slide rod 23. The propulsion motor 21 drives the threaded rod 22 to rotate. Under the transmission of the threaded rod 22, the spindle motor 12 moves horizontally along the guide rail on the support base 11.

[0020] In the coal seam drilling operation, the flange 13 is first driven to rotate by the spindle motor 12. When the drill bit required for drilling is installed on the flange 13, the rotation of the flange 13 drives the rotation of the drill bit to achieve drilling. During drilling, the threaded rod 22 is driven to rotate by the propulsion motor 21. When the threaded rod 22 rotates, the spindle motor 12 is driven forward by the propulsion of the thread, and the propulsion of the drill bit is achieved.

[0021] In order to solve the above-mentioned problems, by setting up the propulsion component 2, the drilling component 3 and the driving component 4, the space formed by the separation of the drill bit can be used to realize the temporary storage and directional discharge of the slag, and the air pump blowing can be used to enhance the slag discharge effect, effectively solving the problem of hole blockage and drill jamming; the drilling accuracy can also be improved with the help of the stable support of the drill bit, and the drill bit can be cooled by air circulation, providing a technical solution that is both efficient and safe for the detection of deep coal seam fault stress fields, which has important practical significance for promoting the safe mining of deep coal mine resources.

[0022] The operation is as follows: During the initial drilling, the drilling head 32 and the drill rod 34 fit tightly together, and the drilling head 32 and the drill rod 34 rotate simultaneously until the drill rod 34 is embedded in the inner wall of the rock formation. Then the drilling head 32 accelerates and the drill rod 34 rotates slowly, and the drilling head 32 and the drill rod 34 are separated. The drilling head 32 and the drill rod 34 separate and the air hole 48 slides out from the inside of the drill rod 34, and the air blown by the air pump is blown out from the inside of the air hole 48.

[0023] The specific operations are as follows: The top of the flange 13 is connected to the drilling assembly 3, and the drilling assembly 3 includes a drilling rod 31. The front end of the drilling rod 31 is connected to an extension rod 47, and the top of the extension rod 47 is connected to a drilling probe 32. The drilling probe 32 is configured to be conical, and a stepped protrusion is provided on the surface. The end of the spiral groove 33 opened on the surface of the drilling probe 32 corresponds to the notch opened on the isolation cover 36. The debris generated by the drilling of the drilling probe 32 is guided by the spiral groove 33 through the notch on the isolation cover 36 and falls to one side of the isolation cover 36. The surface of the drilling probe 32 is provided with a spiral groove 33, and the end of the drilling probe 32 is connected to the isolation cover 36. The isolation cover 36 has a groove on the side facing away from the drilling probe 32, and the groove wall is configured to be arc-shaped. The arc-shaped groove wall is used to guide the air blown in by the air pump. The structure consisting of the drill head 32, isolation cover 36, and other components is the core execution component that directly acts on the coal seam to crush and guide slag. Its morphological design and functional layout directly determine the efficiency of initial drilling and the smoothness of slag extraction. The drill rod 34, as the key carrier connecting the front and rear drive of the drilling system, works in conjunction with drive and connection components such as the transmission sleeve 41, driving wheel 42, and hydraulic rod 46 to achieve the important functions of controlling the speed difference, adjusting the relative position, and transmitting power between the drill head 32 and drill rod 34. The precise coordination of these components enables efficient linkage throughout the drilling process, avoiding the disconnection problems that may occur when a single structure is operated.

[0024] The outer surfaces of the drilling rod 31 and the extension rod 47 are sleeved with a drilling rod 34, and the top of the drilling rod 31 is fixedly connected to the extension rod 47. The surface of the extension rod 47 is provided with an air hole 48. The interior of the drilling rod 31 and the extension rod 47 is set to a hollow structure. One end of the drilling rod 31 is connected to the air pump, and the air pump blows air from the drilling rod 31 to the interior of the extension rod 47. The air blown by the air pump can be used to cool the drilling probe 32 to prevent the drilling probe 32 from overheating, and can also eliminate the risk of increased gas accumulation and fire under the action of air circulation. An isolation cover 36 is provided on the surface of the drill rod 34, and a collar 45 and a transmission sleeve 41 are connected to the outer surface of the drill rod 34. The drilling rod 31 and the drill rod 34 are movably connected, and the transmission motor 44 drives the driving wheel 42 and the transmission belt 43 to drive the transmission sleeve 41 to rotate. The rotation of 41 drives the drill rod 34 to rotate. The rotation of the drill rod 34 and the rotation of the drilling head 32 are used for drilling the coal seam. The active connection between the drill rod 34 and the drilling rod 31 is used for the back and forth sliding between the drilling rod 31 and the drill rod 34, and the rotation of the drill rod 34 on the surface of the drilling rod 31. The outer surface of the transmission sleeve 41 is sleeved with a transmission belt 43, and the inner side of the transmission belt 43 is installed with a driving wheel 42. A transmission motor 44 is installed on the support base 11, and the output end of the transmission motor 44 is connected to the driving wheel 42. The transmission motor 44 drives the transmission sleeve 41 and the drill rod 34 to rotate. A hydraulic rod 46 is also installed on the support base 11. The output end of the hydraulic rod 46 is connected to the collar 45. The collar 45 and the drill rod 34 are rotatably connected. The hydraulic rod 46 drives the collar 45 and the drill rod 34 to move back and forth.

[0025] When drilling the coal seam, the main shaft motor 12 drives the flange 13 to rotate. When the flange 13 rotates, it drives the drilling rod 31 to rotate. When the drilling rod 31 rotates, it drives the drilling head 32 to rotate. At the same time, the drill rod 34 also rotates synchronously. At the beginning of drilling, the drilling head 32 and the drill rod 34 are tightly connected. At this time, the rotation of the drilling head 32 can not only drive the drilling head 32 to rotate, but also drive the drill rod 34 to rotate. As the drilling head 32 rotates, it is continuously embedded in the interior of the coal seam. During the rotation of the drill head 32, the slag stripped by drilling is discharged through the spiral groove 33 on the surface of the drill head 32. When passing through the drill head 32, the slag is gradually guided to pass through the notch provided on the isolation cover 36. The spiral groove 33 and the notch provided on the isolation cover 36 are used to discharge the slag. During this period, the drill rod 34 follows the rotation of the drill head 32, and the rotation of the drill rod 34 also drills the coal seam. The drilled slag is then transported to the inside of the slag discharge trough 35 through the spiral groove 33, and then discharged from the drill hole through the slag discharge trough 35. However, when the slag is discharged, it may not be discharged in time, resulting in slag accumulation within the spiral groove 33 and the slag discharge groove 35. This not only increases the resistance to the rotation of the drill rod 31 and causes a sudden increase in the load on the spindle motor 12, but also may cause local temperature rise due to the continuous friction between the accumulated slag and the drill head 32 and drill rod 34, exacerbating drill bit wear and increasing the risk of gas ignition at high temperatures. More seriously, if the accumulated slag forms agglomerates and blocks the slots in the isolation cover 36, the drilling operation will be interrupted, requiring shutdown and cleaning before resumption. This not only prolongs the construction period, but also causes fluctuations in the contact stress between the drill rod 31 and the coal seam due to frequent starts and stops, affecting the accuracy of the drilling trajectory and, in turn, interfering with the accuracy of the coal seam fault stress field detection data.

[0026] In order to avoid such a problem, as the drill head 32 and the drill rod 34 are continuously advanced until the drill rod 34 is completely embedded in the coal seam, the drill head 32 will accelerate its rotation. When the drill head 32 accelerates its rotation, the drill head 32 and the drill rod 34 are separated. The separation of the drill head 32 and the drill rod 34 can be completed by switch control. After separation, the drill head 32 accelerates its rotation to continue drilling, and the drill rod 34 reduces its rotation speed. At this time, the rotation speed of the drill rod 34 is reduced but does not stop. At this time, the rotation of the drill rod 34 continuously discharges slag to the outside. The distance between the drill head 32 and the drill rod 34 is continuously increased, so that a cavity is formed between the drill head 32 and the drill rod 34. The cavity is used to store the slag produced by the drill head 32 during drilling. To prevent internal blockage, air is injected into the cavity. The air agitates the slag, which is then discharged from the slag discharge groove 35 provided on the drill rod 34 by the air flow. In this way, internal blockage is avoided. The above-mentioned continuous increase in the distance between the drilling head 32 and the drill rod 34 is completed by the withdrawal and contraction of the hydraulic rod 46. Since the drill rod 34 is sleeved on the surface of the drilling rod 31, the movement of the drill rod 34 is not affected by the drilling rod 31. When the hydraulic rod 46 begins to contract, it drives the collar 45 to move. When the collar 45 moves, it drives the drill rod 34 to move. At this time, the drill rod 34 slides on the drilling rod 31. In order to ensure the normal rotation of the drill rod 34 during the sliding period, the drill rod 34 and the collar 45 are rotatably connected by a movable shaft. In this way, the collar 45 drives the drill rod 34 to slide horizontally without affecting the rotation of the drill rod 34. Regarding the rotation of the drill rod 34, the driving wheel 42 is driven by the transmission motor 44 to rotate. When the driving wheel 42 rotates, the transmission belt 43 sleeved on the outer surface of the driving wheel 42 and the transmission sleeve 41 starts to rotate. Under the transmission of the transmission belt 43, the transmission sleeve 41 is driven to rotate. The rotation of the transmission sleeve 41 drives the rotation of the drill rod 34. The surface of the drill rod 34 is provided with axially arranged raised strips, and the raised blocks are embedded in the interior of the transmission sleeve 41. At this time, the rotation of the transmission sleeve 41 will drive the transmission sleeve 41 to rotate through the raised strips. The setting of the raised strips not only provides support for the rotation of the transmission sleeve 41, but also limits the lateral sliding of the drill rod 34. When the hydraulic rod 46 contracts, it drives the slide of the drill rod 34. At this time, the drill rod 34 will slide inside the transmission sleeve 41. The setting of the raised strips also ensures the stability of the drill rod 34 when sliding.

[0027] Finally, when the drilling head 32 and the drill rod 34 are separated, the air hole 48 originally covered by the drill rod 34 will be exposed during the sliding. At this time, the air pump is connected to the drilling rod 31, and the air pump blows air into the interior of the drilling rod 31. The air enters the interior of the extension rod 47 through the drilling rod 31 and is finally discharged from the interior of the air hole 48. Since the drilling head 32 is rotating, the air hole 48 also rotates continuously. The rotation of the air hole 48 changes the position of the air outlet, and air is blown into the cavity between the drilling head 32 and the drill rod 34 through the air hole 48, so that the slag in the cavity is blown up and then discharged through the slag discharge chute 35. The slag discharge efficiency is also higher. At the same time, due to the continuous injection of air into the cavity, the pressure in the cavity is high. Under such an environment, the internal slag can be pushed toward the low pressure side by the air pressure, and the slag in the cavity is discharged through the slag discharge chute 35. In addition, in order to ensure the internal ventilation, as the drill rod 34 moves, the air holes 48 originally covered by the drill rod 34 are gradually removed, from the original one air hole 48 corresponding to the cavity to the last three air holes 48 corresponding to the cavity. By increasing the amount of air outlet, the range of air blowing is ensured to be more comprehensive.

[0028] The technical scope of the present invention is not limited to the contents of the above description. Those skilled in the art can make various deformations and modifications to the above embodiments without departing from the technical idea of ​​the present invention, and these deformations and modifications should all fall within the protection scope of the present invention.

Claims

1. A drilling device for detecting fault stress fields in deep coal seams in mining areas, characterized in that: It includes a support base, a spindle motor is installed on the top of the support base, and the output end of the spindle motor is connected to a flange; The top of the flange is connected to a drilling assembly, which includes a drilling rod, the front end of the drilling rod is connected to an extension rod, the top of the extension rod is connected to a drilling probe, the surface of the drilling probe is provided with a spiral groove, the end of the drilling probe is connected to an isolation cover, the outer surfaces of the drilling rod and the extension rod are sleeved with the drill rod, the surface of the drill rod is provided with an isolation cover, the outer surface of the drill rod is connected with a collar and a transmission sleeve, the outer surface of the transmission sleeve is sleeved with a transmission belt, a driving wheel is installed on the inner side of the transmission belt, a transmission motor is installed on the support base, the output end of the transmission motor is connected to the driving wheel, the transmission motor drives the transmission sleeve and the drill rod to rotate, and a hydraulic rod is also installed on the support base, the output end of the hydraulic rod is connected with a collar, the collar and the drill rod are rotatably connected, and the hydraulic rod drives the collar and the drill rod to move back and forth.

2. The drilling device for detecting fault stress fields in deep coal seams in mining areas according to claim 1, characterized in that: A propulsion assembly is installed on the inner side of the support base. The propulsion assembly includes a propulsion motor. The output end of the propulsion motor is connected to a threaded rod. The bottom end of the support base is connected to a sliding rod.

3. The drilling device for detecting fault stress fields in deep coal seams in mining areas according to claim 2, characterized in that: The propulsion motor drives the threaded rod to rotate, and the spindle motor moves horizontally along the guide rail on the support base under the transmission of the threaded rod.

4. The drilling device for detecting fault stress fields in deep coal seams in mining areas according to claim 1, characterized in that: An extension rod is fixedly connected to the top of the drilling rod, and air holes are opened on the surface of the extension rod. The interior of the drilling rod and the extension rod is set as a hollow structure. One end of the drilling rod is connected to an air pump, and the air blown by the air pump is transported from the drilling rod to the interior of the extension rod.

5. The drilling device for detecting fault stress fields in deep coal seams in mining areas according to claim 1, characterized in that: The drilling rod and the drill bit are movably connected, the transmission motor drives the driving wheel and the transmission belt to drive the transmission sleeve to rotate, and the rotation of the transmission sleeve drives the drill rod to rotate. The rotation of the drill rod and the drilling head is used for drilling the coal seam.

6. The drilling device for detecting fault stress fields in deep coal seams in mining areas according to claim 5, characterized in that: The movable connection between the drill rod and the drilling rod is used for the forward and backward sliding between the drill rod and the drill rod, and the rotation of the drill rod on the surface of the drilling rod.

7. The drilling device for detecting fault stress fields in deep coal seams in mining areas according to claim 1, characterized in that: The drilling probe is configured to be conical, and a stepped protrusion is provided on the surface.

8. The drilling device for detecting fault stress fields in deep coal seams in mining areas according to claim 7, characterized in that: The end of the spiral groove on the surface of the drilling head corresponds to the notch on the isolation cover, and the debris generated by the drilling of the drilling head is guided by the spiral groove through the notch on the isolation cover and falls to one side of the isolation cover.

9. The drilling device for detecting fault stress fields in deep coal seams in mining areas according to claim 1, characterized in that: A groove is provided on the side of the isolation cover facing away from the drilling probe, and the groove wall is arranged in an arc shape, and the arc-shaped groove wall is used to guide the air blown in by the air pump.

10. The drilling device for detecting fault stress field of deep coal seams in a mining area according to claim 1, characterized in that: During the initial drilling, the drill head and the drill rod fit tightly together, and the drill head and the drill rod rotate at the same time until the drill rod is embedded in the inner wall of the rock formation. After that, the drill head accelerates and the drill rod rotates slowly, and the drill head and the drill rod are separated. The air hole of the drill head and the drill rod are separated slides out from the inside of the drill rod, and the air blown by the air pump is blown out from the inside of the air hole.

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