An electromechanical borehole core drilling tool for polar drilling

Abstract

This invention discloses an electromechanical borehole coring tool for polar drilling, comprising a housing, a support system, a borehole coring system, and a control system. The control system, support system, and borehole coring system are sequentially assembled within the housing. The control system is connected to both the support system and the borehole coring system, controlling their operation. The housing consists of an upper housing and a lower housing, with the upper housing located above the lower housing. A cable chamber is located at the top of the upper housing, housing a cable terminal and a cable connector. The upper end of the cable terminal is connected to an armored cable, and the lower end is connected to the control system via the cable connector. Advantages include: good formation adaptability, suitable for drilling through ice layers containing rock particles; a simple and compact overall structure, small and lightweight size, large coring diameter, and long single coring length, significantly reducing auxiliary time for tripping in and out of the drill string and effectively improving drilling efficiency.

Description

Technical Field

[0001] This invention relates to a borehole core drilling tool, and more particularly to an electromechanical borehole core drilling tool for polar drilling. Background Technology

[0002] Currently, the ice layers deep within glaciers contain a wealth of climate and environmental information. This information is invaluable for studying past climate and environmental changes, monitoring current climate and environmental conditions, and predicting future climate change. Furthermore, analysis of ice cores allows for in-depth research into biogeochemical cycles, volcanic activity, and cosmic events at different periods. Therefore, obtaining ancient, deep ice cores is crucial for studying global climate and environmental change and reconstructing Earth's historical evolution, leading many countries to undertake deep ice core drilling projects in polar regions. With the development of polar science, obtaining additional ice core samples from specific well sections has become an important direction in polar research. This is because for specific ice layers of high scientific value, the combination of ice core parameters that need to be tested increases significantly, the demand for ice core samples is large, and additional ice core data can verify the results of existing ice core analyses. Moreover, in the event of sample loss, damage, or contamination during drilling, transportation, storage, or analysis, additional ice cores can be used as a backup. Therefore, obtaining additional ice cores at specific depths within the ice layer is of great significance to polar scientific research.

[0003] However, obtaining additional deep ice cores using conventional drilling methods involves numerous boreholes, high costs, and long cycles, severely hindering the development of polar scientific research. Therefore, researchers have proposed using eccentric wedges or support arms at specific borehole depths to provide directional drilling force for the drilling tool, achieving directional coring. However, this method requires frequent drill bit changes, resulting in long auxiliary times, low coring efficiency, and complex tool structure. In addition, some researchers have proposed a technique using thermomelting drill bits for borehole wall directional coring. During coring, the thermomelting drill bit first extends laterally to melt the ice layer on the borehole wall, then descends to melt the ice and drill for the ice core. After reaching the designed length, the drill bit is raised to the middle of the ice core and retracted, simultaneously pulling the ice core back into the drilling tool to complete the coring. However, this technique is difficult to advance when encountering ice layers containing rock particles, as the high melting point of the rock makes it difficult for the thermomelting drill bit to advance further, and its poor formation adaptability fails to meet drilling requirements. Therefore, a borehole wall coring tool for ice layers with strong formation adaptability, simple structure, and high coring efficiency is needed. Summary of the Invention

[0004] The purpose of this invention is to solve the problems of poor formation applicability, complex structure and low drilling efficiency of drilling tools in current ice layer core drilling, and to provide an electromechanical core drilling tool for polar drilling.

[0005] The electromechanical borehole coring tool for polar drilling provided by the present invention includes a housing, a support system, a borehole coring system, and a control system. The control system, the support system, and the borehole coring system are sequentially assembled in the housing. The control system is connected to the support system and the borehole coring system respectively, and controls the operation of the support system and the borehole coring system.

[0006] The housing is divided into an upper housing and a lower housing. The upper housing is located above the lower housing. A cable chamber is located at the top of the upper housing. The cable chamber is equipped with cable terminals and cable connectors. The upper end of the cable terminal is connected to the armored cable, and the lower end of the cable terminal is connected to the control system through the cable connector. Two support systems are provided. The support systems are assembled in the upper housing below the control system. Two through holes are opened on the side wall of the upper housing. The two through holes correspond to the two cams of the two support systems, respectively.

[0007] Each support system includes a rotating shaft, a cam, and a first electric push rod. One end of the rotating shaft is hinged to a support plate inside the upper housing cavity, and the other end is connected to the cam. The cam is configured to correspond to a through hole on the side wall of the upper housing. Driven by the rotating shaft, the cam can extend out of the side wall of the upper housing and engage with the borehole wall. One end of the first electric push rod is hinged to a horizontal plate inside the upper housing cavity corresponding to the support plate, and the other end is connected to the rotating shaft. The first electric push rod can drive the rotating shaft to rotate, thereby causing the cam to extend out of the side wall of the upper housing and engage with the borehole wall. The cam has several protruding teeth around its circumference for engaging with the borehole wall. The first electric push rod is connected to and controlled by the control system.

[0008] The borehole coring system includes a sleeve, a second electric push rod, a third electric push rod, a linkage mechanism, a drill bit drive mechanism, and a drill bit. The sleeve is mounted on the lower part of the upper housing, and its outer diameter is smaller than the inner diameter of the upper housing. The sleeve can slide up and down within the inner cavity of the upper housing. The bottom end of the sleeve is fixedly connected to the upper part of the lower housing. As the sleeve slides up and down within the inner cavity of the upper housing, it drives the lower housing to slide synchronously. The upper end of the second electric push rod is connected to a support plate at the lower part of the upper housing, and its lower end is fixedly connected to the bottom of the sleeve. The second electric push rod drives the sleeve to slide up and down within the inner cavity of the upper housing. The lower part of the second electric push rod is equipped with… The first load cell monitors the thrust of the second electric push rod and is connected to the control system. It transmits the collected data to the control system in real time. A first displacement sensor is installed at the bottom of the sleeve cavity. This sensor monitors the extension and retraction distance of the second electric push rod and is also connected to the control system. The second electric push rod is connected to and controlled by the control system. The upper end of the third electric push rod is fixed to the lower part of the sleeve base plate, and the lower end is connected to the connecting plate. The upper end of the third electric push rod is equipped with a second load cell, which monitors the thrust of the third electric push rod. The second load cell is connected to the control system and can transmit the collected data to the control system in real time. The lower part of the sleeve base plate is equipped with a second displacement sensor, which monitors the extension distance of the third electric push rod. The second displacement sensor is connected to the control system and can transmit the collected data to the control system in real time. The third electric push rod is connected to the control system and is controlled by the control system. The bottom of the connecting plate is connected to an extension rod, and the lower end of the extension rod is connected to the slider. The extension rod and slider are connected, and two are respectively assembled and installed symmetrically. The slider is installed in the groove set in the middle of the positioning block. Under the drive of the upper extension rod and the third electric push rod, the slider can slide up and down in the groove. The lower end of the slider is connected to the upper end of the linkage mechanism, and the lower end of the linkage mechanism is connected to the drill bit. The drill bit is assembled at the opening opened on the side wall of the lower housing. During the up and down sliding of the slider, it can drive the linkage mechanism to drive the drill bit to move left and right and extend out of the side wall of the lower housing for operation. The drill bit drive mechanism is connected to the drill bit and drives the drill bit to rotate. The drill bit drive mechanism is connected to the control system and is controlled by the control system.

[0009] The linkage mechanism includes a first link, a second link, and a third link. Two of each of the first, second, and third links are assembled and arranged symmetrically front to back. The upper end of the first link is connected to the slider via a pin, and the lower end of the first link is connected to the middle of the second link via a pin. The left end of the second link is connected to the positioning block via a pin, and the right end of the second link is connected to the drill bit. The second and third links are arranged parallel vertically. The left end of the third link is connected to the positioning block via a pin, and the right end of the third link is connected to the drill bit. The second and third links can drive the drill bit to move left and right.

[0010] The drill bit consists of an upper drill bit body and a lower drill bit body, which are screwed together. The drill bit drive mechanism includes a drill bit support sleeve, a first gear, a second gear, a chain, cutter heads, a telescopic universal joint, a first motor, and a first encoder. The upper and lower drill bit bodies are installed inside the drill bit support sleeve. The upper end of the first gear is mounted on the bottom of the drill bit support sleeve via a bearing, and the lower end of the first gear is connected to the output shaft of the first motor via the telescopic universal joint. The second gear is fixedly installed on the periphery of the lower drill bit body. The first gear and the second gear are connected by a chain, and several cutter heads are mounted on the bottom of the chain via pins. The cutter heads are used to cut the ice columns remaining around the ice core and can sweep the ice debris into the main borehole. The first encoder is mounted on the output shaft of the first motor and monitors the output speed of the first motor in real time. Both the first encoder and the first motor are connected to the control system. The first encoder can transmit the collected data to the control system in real time, and the control system controls the operation of the first motor.

[0011] The bottom of the lower housing is equipped with a reaming system, which includes a second motor, a second encoder, and a reaming drill bit. The second motor is installed in the lower part of the inner cavity of the lower housing, and the second encoder is installed on the output shaft of the second motor. The second encoder monitors the output speed of the second motor in real time. The reaming drill bit is screwed onto the output shaft of the second motor, and the second motor drives the reaming drill bit to rotate. The second encoder and the second motor are connected to the control system. The second encoder can transmit the collected data to the control system in real time, and the control system controls the operation of the second motor.

[0012] The control system is connected to the ground controller via an armored cable. The control system includes a signal input unit, a signal processing unit, and a signal output unit. The signal input unit is connected to the signal processing unit, which in turn is connected to the signal output unit. The signal input unit transmits received data to the signal processing unit for processing, and the processed data is then transmitted outwards via the signal output unit. The signal input unit is also connected to a first displacement sensor, a second displacement sensor, a first weighing sensor, a second weighing sensor, a first encoder, and a second encoder. The signal input unit receives data from these sensors in real time. The signal output unit is also connected to a first electric actuator, a second electric actuator, a third electric actuator, a first motor, and a second motor. The signal output unit controls the operation of these actuators. The signal input and signal output units are also connected to a ground signal unit, enabling the ground system to control the downhole drilling tools.

[0013] The first electric actuator, second electric actuator, third electric actuator, first motor, second motor, first displacement sensor, second displacement sensor, first weighing sensor, second weighing sensor, first encoder, second encoder, signal input unit, signal processing unit, and signal output unit mentioned above are all assemblies of existing equipment; therefore, their specific models and specifications are not detailed.

[0014] The working principle of this invention is as follows:

[0015] The electromechanical borehole coring tool for polar drilling provided by this invention requires the creation of a pre-defined cavity in the borehole wall above a predetermined depth to ensure the smooth extension of the borehole coring system. The drill bit is lowered into the borehole to the predetermined depth using a ground winch and armored cable. If borehole diameter reduction occurs during lowering, a second motor drives the reaming drill bit to rotate, expanding the borehole diameter and ensuring smooth lowering of the drill bit. Upon reaching the predetermined depth, two support mechanisms are simultaneously activated. The first electric push rod extends outward, and the cam rotates with the rotating shaft, extending the drill bit. The teeth on the outer periphery of the cam then engage the borehole wall, ensuring the drill bit is fixed in the predetermined position. After the drill bit is fixed, the third electric push rod retracts, pulling the extension rod, slider, and first connecting rod upward. Simultaneously, the first connecting rod rotates around the pin connected to the slider, causing the second and third connecting rods to rotate counterclockwise around the positioning block, thereby rotating the drill bit support sleeve and the drill bit, allowing the drill bit to extend from the opening in the lower housing. The retraction distance of the third electric push rod is monitored using a second displacement sensor. When the second and third connecting rods are horizontal, i.e., the drill bit is fully extended from the drill string, the third electric push rod stops operating. The control system controls the first motor to operate, which drives the first gear to rotate via a telescopic universal joint. This, in turn, drives the second gear, upper drill bit body, and lower drill bit body to rotate simultaneously via chain transmission. The speed of the first motor is monitored using a first encoder, which in turn controls the drill bit speed through the control system. The second electric push rod is controlled to extend outward, and the sleeve extends from the upper housing, which in turn drives the lower housing and the borehole core-taking system downward to achieve borehole core drilling. Several cutting heads mounted below the chain rotate with the chain, rotating to cut the remaining ice columns around the ice core and bringing the ice debris generated during drilling into the main borehole. The extension distance of the second electric push rod is monitored using a first displacement sensor. After the second electric push rod reaches its maximum extension distance, the control system controls the second electric push rod and the first motor to stop operating. The drill string is slowly lowered using an armored cable, and the cam rolls along the borehole wall to continue core drilling. Once the predetermined coring length is reached, the third electric push rod extends, driving the slider downwards. This, in turn, retracts the drill bit via a linkage mechanism. During the drill bit retraction, the ice core is broken off and retracts into the drill string along with the drill bit. After the drill bit and ice core are fully retracted, the first electric push rod retracts, causing the cam to rotate with the rotating shaft and retract into the drill string. The drill string is then lifted out of the borehole using an armored cable, completing the coring operation.

[0016] The beneficial effects of this invention are:

[0017] The electromechanical borehole core drilling tool for polar drilling provided by this invention uses a motor to drive the gears to rotate, which in turn drives the drill bit to rotate via a chain drive. It has good formation adaptability and is suitable for drilling in ice layers containing rock particles. The overall structure of the drilling tool is simple and compact, small in size and lightweight. The surface equipment can be used interchangeably with existing equipment. It also has a large core diameter and a long single core length, which greatly shortens the auxiliary time for tripping the drilling tool, effectively improves drilling efficiency, and significantly reduces the burden of polar logistics support. It is suitable for drilling in ice layers in the complex and harsh polar environment. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the overall structure of the electromechanical borehole core drilling tool for polar drilling described in this invention.

[0019] Figure 2 This is a schematic diagram of the support system structure described in this invention.

[0020] Figure 3 This is a three-dimensional structural diagram of the borehole coring system described in this invention.

[0021] Figure 4 This is a schematic diagram of the drill bit drive mechanism described in this invention.

[0022] Figure 5 This is a schematic diagram of the lower shell structure described in this invention.

[0023] Figure 6 This is a connection diagram of the control system described in this invention.

[0024] Figure 7 This is a schematic diagram of the borehole coring system of the present invention, showing the principle of the drill string extending outwards.

[0025] Figure 8 This is a schematic diagram illustrating the downward drilling principle of the borehole coring system described in this invention.

[0026] Figure 9 This is a schematic diagram illustrating the principle of the completion of coring drilling as described in this invention.

[0027] The annotations in the image above are as follows:

[0028] 1. Control system 2. Upper housing 3. Lower housing 4. Cable compartment 5. Cable terminal

[0029] 6. Cable connector 7. Armored cable 8. Through hole 9. Cam 10. Rotating shaft

[0030] 11. First electric push rod; 12. Support plate; 13. Horizontal plate; 14. Sleeve

[0031] 15. Second electric actuator; 16. Third electric actuator; 17. Drill bit; 18. First weighing sensor

[0032] 19. First displacement sensor; 20. Connecting plate; 21. Second weighing sensor

[0033] 22. Second displacement sensor; 23. Extension rod; 24. Slider; 25. Positioning block; 26. Slide groove

[0034] 27. Opening; 28. First connecting rod; 29. ​​Second connecting rod; 30. Third connecting rod; 31. Upper drill bit body.

[0035] 32. Lower drill bit body; 33. Drill bit support sleeve; 34. First gear; 35. Second gear

[0036] 36. Chain; 37. Cutter head; 38. Telescopic universal joint; 39. First motor.

[0037] 40. First encoder; 41. Second motor; 42. Second encoder; 43. Reamer bit

[0038] 44. Signal Input Unit; 45. Signal Processing Unit; 46. Signal Output Unit

[0039] 47. Ground signal unit. Detailed Implementation

[0040] Please see Figures 1 to 9 As shown:

[0041] The electromechanical borehole coring tool for polar drilling provided by the present invention includes a housing, a support system, a borehole coring system, and a control system 1. The control system 1, the support system, and the borehole coring system are sequentially assembled inside the housing. The control system 1 is connected to the support system and the borehole coring system respectively, and controls the operation of the support system and the borehole coring system.

[0042] The housing is divided into an upper housing 2 and a lower housing 3. The upper housing 2 is located above the lower housing 3. A cable chamber 4 is provided at the top of the upper housing 2. A cable terminal 5 and a cable connector 6 are installed in the cable chamber 4. The upper end of the cable terminal 5 is connected to the armored cable 7, and the lower end of the cable terminal 5 is connected to the control system 1 through the cable connector 6. Two support systems are provided. The support systems are installed in the upper housing 2 below the control system 1. Two through holes 8 are opened on the side wall of the upper housing 2. The two through holes 8 are respectively set with two cams 9 of the two support systems.

[0043] Each support system includes a rotating shaft 10, a cam 9, and a first electric push rod 11. One end of the rotating shaft 10 is hinged to a support plate 12 in the inner cavity of the upper housing 2, and the other end of the rotating shaft 10 is connected to the cam 9. The cam 9 is set with a through hole 8 on the side wall of the upper housing 2. The cam 9 can extend out of the side wall of the upper housing 2 and engage with the hole wall of the drilled hole under the drive of the rotating shaft 10. One end of the first electric push rod 11 is hinged to a horizontal plate 13 in the inner cavity of the upper housing 2 corresponding to the support plate 12, and the other end of the first electric push rod 11 is connected to the rotating shaft 10. The first electric push rod 11 can drive the rotating shaft 10 to rotate, thereby driving the cam 9 to extend out of the side wall of the upper housing 2 and engage with the hole wall of the drilled hole. The cam 9 has several protruding teeth around its circumference for engaging with the hole wall of the drilled hole. The first electric push rod 11 is connected to the control system 1 and is controlled by the control system 1.

[0044] The borehole coring system includes a sleeve 14, a second electric push rod 15, a third electric push rod 16, a linkage mechanism, a drill bit drive mechanism, and a drill bit 17. The sleeve 14 is mounted on the lower part of the upper housing 2. The outer diameter of the sleeve 14 is smaller than the inner diameter of the upper housing 2, allowing it to slide up and down within the inner cavity of the upper housing 2. The bottom end of the sleeve 14 is fixedly connected to the upper part of the lower housing 3. As the sleeve 14 slides up and down within the inner cavity of the upper housing 2, it drives the lower housing 3 to slide synchronously. The upper end of the second electric push rod 15 is connected to the support plate 12 at the lower part of the upper housing 2. The lower end of the second electric push rod 15 is fixed to the bottom of the sleeve 14. The second electric push rod 15 can drive the sleeve 14 to slide up and down in the inner cavity of the upper housing 2. The lower part of the second electric push rod 15 is equipped with a first weighing sensor 18, which is used to monitor the thrust of the second electric push rod 15. The first weighing sensor 18 is connected to the control system 1 and can transmit the collected data to the control system 1 in real time. The bottom of the inner cavity of the sleeve 14 is equipped with a first displacement sensor 19. Device 19 is used to monitor the extension distance of the second electric push rod 15. The first displacement sensor 19 is connected to the control system 1 and can transmit the collected data to the control system 1 in real time. The second electric push rod 15 is connected to the control system 1 and is controlled by the control system 1. The upper end of the third electric push rod 16 is fixed to the lower part of the bottom plate of the sleeve 14, and the lower end of the third electric push rod 16 is connected to the connecting plate 20. The upper end of the third electric push rod 16 is equipped with a second weighing sensor 21, which is used to monitor the thrust of the third electric push rod 16. The second weighing sensor 21 is connected to the control system 1 and can transmit the collected data to the control system 1 in real time. The lower part of the bottom plate of the sleeve 14 is equipped with a second displacement sensor 22, which is used to monitor the extension distance of the third electric push rod 16. The second displacement sensor 22 is connected to the control system 1 and can transmit the collected data to the control system 1 in real time. The third electric push rod 16 is connected to the control system 1 and is controlled by the control system 1.An extension rod 23 is connected to the bottom of the connecting plate 20. The lower end of the extension rod 23 is connected to the slider 24. Two extension rods 23 and two sliders 24 are respectively assembled and installed symmetrically. The slider 24 is installed in the groove 26 set in the middle of the positioning block 25. The slider 24 can slide up and down in the groove 26 under the drive of the upper extension rod 23 and the third electric push rod 16. The lower end of the slider 24 is connected to the upper end of the linkage mechanism. The lower end of the linkage mechanism is connected to the drill bit 17. The drill bit 17 is assembled at the opening 27 opened on the side wall of the lower housing 3. During the up and down sliding of the slider 24, it can drive the linkage mechanism to drive the drill bit 17 to move left and right and extend out of the side wall of the lower housing 3 for operation. The drill bit drive mechanism is connected to the drill bit 17 and drives the drill bit 17 to rotate. The drill bit drive mechanism is connected to the control system 1 and is controlled by the control system 1.

[0045] The linkage mechanism includes a first link 28, a second link 29, and a third link 30. Two of each of the first link 28, second link 29, and third link 30 are assembled and arranged symmetrically front to back. The upper end of the first link 28 is connected to the slider 24 via a pin, and the lower end of the first link 28 is connected to the middle of the second link 29 via a pin. The left end of the second link 29 is connected to the positioning block 25 via a pin, and the right end of the second link 29 is connected to the drill bit 17. The second link 29 and the third link 30 are arranged parallel to each other vertically. The left end of the third link 30 is connected to the positioning block 25 via a pin, and the right end of the third link 30 is connected to the drill bit 17. The second link 29 and the third link 30 can drive the drill bit 17 to move left and right.

[0046] Drill bit 17 consists of an upper drill bit body 31 and a lower drill bit body 32, which are screwed together. The drill bit drive mechanism includes a drill bit support sleeve 33, a first gear 34, a second gear 35, a chain 36, a cutter head 37, a retractable universal joint 38, a first motor 39, and a first encoder 40. The upper drill bit body 31 and the lower drill bit body 32 are installed inside the drill bit support sleeve 33. The upper end of the first gear 34 is mounted on the bottom of the drill bit support sleeve 33 via a bearing, and the lower end of the first gear 34 is connected to the output shaft of the first motor 39 via the retractable universal joint 38. The second gear 35 is fixedly mounted on... The lower drill bit body 32 is surrounded by a first gear 34 and a second gear 35 connected by a chain 36. Several cutter heads 37 are mounted on the bottom of the chain 36 via pins. The cutter heads 37 are used to cut the ice columns remaining around the ice core and can sweep the ice debris into the main borehole. A first encoder 40 is installed on the output shaft of a first motor 39. The first encoder 40 monitors the output speed of the first motor 39 in real time. Both the first encoder 40 and the first motor 39 are connected to the control system 1. The first encoder 40 can transmit the collected data to the control system 1 in real time. The control system 1 controls the operation of the first motor 39.

[0047] The bottom of the lower housing 3 is equipped with a hole-reaming system, which includes a second motor 41, a second encoder 42, and a hole-reaming drill bit 43. The second motor 41 is installed in the lower part of the inner cavity of the lower housing 3, and the second encoder 42 is installed on the output shaft of the second motor 41. The second encoder 42 monitors the output speed of the second motor 41 in real time. The hole-reaming drill bit 43 is screwed onto the output shaft of the second motor 41, and the second motor 41 drives the hole-reaming drill bit 43 to rotate. The second encoder 42 and the second motor 41 are connected to the control system 1. The second encoder 42 can transmit the collected data to the control system 1 in real time, and the control system 1 controls the operation of the second motor 41.

[0048] Control system 1 is connected to the ground controller via armored cable 7. Control system 1 includes a signal input unit 44, a signal processing unit 45, and a signal output unit 46. The signal input unit 44 is connected to the signal processing unit 45, and the signal processing unit 45 is also connected to the signal output unit 46. The signal input unit 44 transmits the received data to the signal processing unit 45 for processing, and the processed data is transmitted outward via the signal output unit 46. The signal input unit 44 is also connected to the first displacement sensor 19, the second displacement sensor 22, the first weighing sensor 18, the second weighing sensor 21, the first encoder 40, and the second encoder 42. Unit 44 receives data in real time from the first displacement sensor 19, the second displacement sensor 22, the first weighing sensor 18, the second weighing sensor 21, the first encoder 40, and the second encoder 42. The signal output unit 46 is also connected to the first electric push rod 11, the second electric push rod 15, the third electric push rod 16, the first motor 39, and the second motor 41. The signal output unit 46 controls the operation of the first electric push rod 11, the second electric push rod 15, the third electric push rod 16, the first motor 39, and the second motor 41. The signal input unit 44 and the signal output unit 46 are also connected to the ground signal unit 47 to realize the control of the downhole drilling tools by the ground system.

[0049] The first electric push rod 11, the second electric push rod 15, the third electric push rod 16, the first motor 39, the second motor 41, the first displacement sensor 19, the second displacement sensor 22, the first weighing sensor 18, the second weighing sensor 21, the first encoder 40, the second encoder 42, the signal input unit 44, the signal processing unit 45, and the signal output unit 46 mentioned above are all assemblies of existing equipment. Therefore, their specific models and specifications are not described in detail.

[0050] The working principle of this invention is as follows:

[0051] The electromechanical borehole coring tool for polar drilling provided by this invention requires the creation of a cavity of a predetermined size in the borehole wall above a predetermined depth to ensure the smooth extension of the borehole coring system. The drill bit is lowered into the borehole to the predetermined depth using a ground winch and armored cable 7. If borehole diameter reduction occurs during lowering, a second motor 41 drives the reaming drill bit 43 to rotate, thereby enlarging the borehole diameter and ensuring the smooth lowering of the drill bit. Upon reaching the predetermined depth, two support mechanisms are activated simultaneously. The first electric push rod 11 extends outward, and the cam 9 rotates with the rotating shaft 10, extending the drill bit. This causes the protruding teeth on the outer periphery of the cam 9 to engage with the borehole wall, ensuring the drill bit is fixed in the predetermined position. After the drill bit is fixed, the third electric push rod 16 is retracted, pulling the extension rod 23, slider 24, and first connecting rod 28 upward. Simultaneously, the first connecting rod 28 rotates around the pin connected to the slider 24, causing the second connecting rod 29 and the third connecting rod 30 to rotate counterclockwise around the positioning block 25, thereby rotating the drill bit support sleeve 33 and the drill bit 17, causing the drill bit 17 to extend from the opening 27 of the lower housing 3. The retraction distance of the third electric push rod 16 is monitored using the second displacement sensor 22. When the second connecting rod 29 and the third connecting rod 30 are horizontal, i.e., when the drill bit 17 is fully extended from the drill bit, the operation of the third electric push rod 16 stops. The control system 1 controls the first motor 39 to operate, driving the first gear 34 to rotate via the retractable universal joint 38, which in turn drives the second gear 35 and the upper drill bit body 31 and lower drill bit body 32 to rotate simultaneously via the chain 36. The speed of the first motor 39 is monitored using the first encoder 40, and the speed of the drill bit 17 is controlled by the control system 1. Control system 1 controls the second electric push rod 15 to extend outward, and the sleeve 14 extends from the upper housing 2, thereby driving the lower housing 3 and the borehole core sampling system downward to achieve borehole core drilling. Several cutter heads 37 mounted below the chain 36 rotate together with the chain 36, rotating to cut the remaining ice columns around the ice core and bringing the ice debris generated during drilling into the main borehole. The first displacement sensor 19 monitors the extension distance of the second electric push rod 15. After the second electric push rod 15 reaches its maximum extension distance, control system 1 controls the second electric push rod 15 and the first motor 39 to stop working, and slowly lowers the drill bit using the armored cable 7. The cam 9 rolls along the borehole wall to continue core drilling. After reaching the predetermined core length, control system 1 controls the third electric push rod 16 to extend, driving the slider 24 downward, and then retracting the drill bit 17 through the linkage mechanism. During the retraction of the drill bit 17, the ice core is broken off and retracted into the drill bit along with the drill bit 17. After the drill bit 17 and the core are fully retracted, the first electric push rod 11 is retracted, the cam 9 rotates with the rotating shaft 10, and is retracted into the drill bit. The drill bit is then pulled out of the borehole using the armored cable 7, thus completing the core extraction.

Claims

1. An electromechanical borehole coring tool for polar drilling, comprising a housing, a support system, a borehole coring system, and a control system, wherein the control system, the support system, and the borehole coring system are sequentially assembled within the housing, the control system is connected to both the support system and the borehole coring system, and the control system controls the operation of the support system and the borehole coring system, characterized in that: The aforementioned borehole coring system includes a sleeve, a second electric push rod, a third electric push rod, a linkage mechanism, a drill bit drive mechanism, and a drill bit. The sleeve is assembled in the lower part of the upper housing, and its outer diameter is smaller than the inner diameter of the upper housing. The sleeve can slide up and down within the inner cavity of the upper housing. The bottom end of the sleeve is fixedly connected to the upper part of the lower housing. During the up-and-down sliding motion of the sleeve within the inner cavity of the upper housing, it can drive the lower housing to slide synchronously. The upper end of the second electric push rod is connected to a support plate at the lower part of the upper housing, and the lower end of the second electric push rod is fixedly connected to the bottom of the sleeve. The second electric push rod can drive the sleeve to slide up and down within the inner cavity of the upper housing. Equipped with a first load cell, which monitors the thrust of the second electric push rod and is connected to the control system, the first load cell transmits the collected data to the control system in real time. A first displacement sensor is installed at the bottom of the sleeve's inner cavity, which monitors the extension and retraction distance of the second electric push rod and is also connected to the control system. The second electric push rod is connected to the control system and is controlled by the control system. The upper end of the third electric push rod is fixed to the lower part of the sleeve's bottom plate, and the lower end of the third electric push rod is connected to the connecting plate. The upper end of the third electric push rod is equipped with a second load cell, which monitors the thrust of the third electric push rod. The second load cell is connected to the control system and transmits the collected data to the control system in real time. The lower part of the sleeve base plate is equipped with a second displacement sensor, which monitors the extension distance of the third electric push rod. The second displacement sensor is also connected to the control system and transmits the collected data to the control system in real time. The third electric push rod is connected to the control system and is controlled by the control system. An extension rod is connected to the bottom of the connecting plate, and the lower end of the extension rod connects to the sliding... The blocks are connected, and two extension rods and sliders are respectively assembled and installed symmetrically. The slider is installed in the groove set in the middle of the positioning block. Under the drive of the upper extension rod and the third electric push rod, the slider can slide up and down in the groove. The lower end of the slider is connected to the upper end of the linkage mechanism, and the lower end of the linkage mechanism is connected to the drill bit. The drill bit is assembled at the opening on the side wall of the lower housing. During the up and down sliding of the slider, it can drive the linkage mechanism to drive the drill bit to move left and right and extend out of the side wall of the lower housing for operation. The drill bit drive mechanism is connected to the drill bit and drives the drill bit to rotate. The drill bit drive mechanism is connected to the control system and is controlled by the control system.The drill bit consists of an upper drill bit body and a lower drill bit body, which are screwed together. The drill bit drive mechanism includes a drill bit support sleeve, a first gear, a second gear, a chain, cutter heads, a retractable universal joint, a first motor, and a first encoder. The upper and lower drill bit bodies are installed inside the drill bit support sleeve. The upper end of the first gear is mounted on the bottom of the drill bit support sleeve via a bearing, and the lower end of the first gear is connected to the output shaft of the first motor via the retractable universal joint. The second gear is fixedly installed on the periphery of the lower drill bit body. The first and second gears are connected by a chain, and several cutter heads are mounted on the bottom of the chain via pins. The cutter heads are used to cut away the ice columns remaining around the ice core and can sweep ice debris into the main borehole. The first encoder is mounted on the output shaft of the first motor and monitors the output speed of the first motor in real time. Both the first encoder and the first motor are connected to the control system. The first encoder can transmit the collected data to the control system in real time, and the control system controls the operation of the first motor.

2. The electromechanical borehole core drilling tool for polar drilling according to claim 1, characterized in that: The housing is divided into an upper housing and a lower housing. The upper housing is located above the lower housing. A cable chamber is located at the top of the upper housing. The cable chamber is equipped with a cable terminal and a cable connector. The upper end of the cable terminal is connected to the armored cable, and the lower end of the cable terminal is connected to the control system through the cable connector. Two support systems are provided. The support systems are assembled in the upper housing below the control system. Two through holes are opened on the side wall of the upper housing. The two through holes correspond to the two cams of the two support systems, respectively.

3. The electromechanical borehole core drilling tool for polar drilling according to claim 2, characterized in that: Each support system includes a rotating shaft, a cam, and a first electric push rod. One end of the rotating shaft is hinged to a support plate in the inner cavity of the upper housing, and the other end of the rotating shaft is connected to the cam. The cam is configured to correspond to a through hole on the side wall of the upper housing. Driven by the rotating shaft, the cam can extend out of the side wall of the upper housing and engage with the hole wall of the drilled hole. One end of the first electric push rod is hinged to a horizontal plate in the inner cavity of the upper housing corresponding to the support plate, and the other end of the first electric push rod is connected to the rotating shaft. The first electric push rod can drive the rotating shaft to rotate, thereby driving the cam to extend out of the side wall of the upper housing and engage with the hole wall of the drilled hole. The cam has several protruding teeth around its circumference for engaging with the hole wall of the drilled hole. The first electric push rod is connected to the control system and is controlled by the control system.

4. The electromechanical borehole core drilling tool for polar drilling according to claim 1, characterized in that: The linkage mechanism includes a first link, a second link, and a third link, wherein two of each of the first, second, and third links are assembled and arranged symmetrically front to back. The upper end of the first link is connected to the slider via a pin, and the lower end of the first link is connected to the middle of the second link via a pin. The left end of the second link is connected to the positioning block via a pin, and the right end of the second link is connected to the drill bit. The second and third links are arranged parallel vertically, with the left end of the third link connected to the positioning block via a pin and the right end of the third link connected to the drill bit. The second and third links can drive the drill bit to move left and right.

5. The electromechanical borehole core drilling tool for polar drilling according to claim 2, characterized in that: The bottom of the lower housing is equipped with a hole-reaming system, which includes a second motor, a second encoder, and a hole-reaming drill bit. The second motor is installed in the lower part of the inner cavity of the lower housing, and the second encoder is installed on the output shaft of the second motor. The second encoder monitors the output speed of the second motor in real time. The hole-reaming drill bit is screwed onto the output shaft of the second motor. The second motor drives the hole-reaming drill bit to rotate. The second encoder and the second motor are connected to the control system. The second encoder can transmit the collected data to the control system in real time, and the control system controls the operation of the second motor.

6. A polar drilling electromechanical borehole core drilling tool according to any one of claims 1 to 5, characterized in that: The control system is connected to the ground controller via an armored cable. The control system includes a signal input unit, a signal processing unit, and a signal output unit. The signal input unit is connected to the signal processing unit, which in turn is connected to the signal output unit. The signal input unit transmits received data to the signal processing unit for processing, and the processed data is transmitted outwards via the signal output unit. The signal input unit is also connected to a first displacement sensor, a second displacement sensor, a first weighing sensor, a second weighing sensor, a first encoder, and a second encoder. The signal input unit receives data from these sensors in real time. The signal output unit is also connected to a first electric actuator, a second electric actuator, a third electric actuator, a first motor, and a second motor. The signal output unit controls the operation of these actuators. The signal input and signal output units are also connected to a ground signal unit, enabling the ground system to control the downhole drilling tools.

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