Deep rock sampling device and sampling method for geological exploration

Abstract

The invention discloses a geological exploration deep rock sampling device and method, and belongs to the technical field of geological rock sampling. The geological exploration deep rock sampling device comprises a hollow drill rod, a drill bit is arranged at the bottom end of the hollow drill rod, a sampling barrel is arranged in the hollow drill rod, and a sampling cavity is formed in the sampling barrel; a plurality of groups of elastic supporting mechanisms for fixing a sampling rock core are axially and uniformly arranged on the inner wall of the sampling cavity, the top end of the sampling barrel is connected with the hollow drill rod through a non-synchronous rotating mechanism, and the upper part and the lower part of the sampling barrel are connected with the hollow drill rod through symmetrically arranged sliding supporting mechanisms; a conical fixing seat for allowing a sampling rock core to enter the sampling cavity is arranged in the bottom end of the hollow drill rod, and a heating element is distributed on the inner wall of the sampling cavity. The geological exploration deep rock sampling device and the geological exploration deep rock sampling method can solve the problems that a traditional sampling rock core is insufficient in supporting and protection, the rock core is prone to abrasion, and the high-temperature state of the rock core cannot be maintained.

Description

Technical Field

[0001] This invention relates to the field of geological rock sampling technology, and in particular to a deep rock sampling device and sampling method for geological exploration. Background Technology

[0002] With the increasing demands in fields such as deep mineral resource exploration and deep-earth scientific research, geological exploration rock sampling technology is developing towards "depth, accuracy, and stability." The core requirement is to obtain core samples that maintain their in-situ quality, providing a reliable basis for subsequent compositional analysis and structural testing. However, existing deep rock sampling technologies still have many key shortcomings, seriously affecting sampling effectiveness and sample quality: Insufficient support and protection for rock cores: Traditional sampling devices often use rigid claws to fix the rock cores. Rigid claws are prone to damaging the surface of the rock cores and destroying their internal structure. Furthermore, the rock cores are prone to shaking and breakage during the lifting process. Defects in the coordination between sampling tube and drill pipe: Traditional sampling tubes are mostly fixedly connected to hollow drill pipes and rotate synchronously with the drill pipes. During the rotation, the rock core and the inner wall of the sampling chamber generate severe friction, causing the rock core to wear and pulverize, and destroying the in-situ structure. At the same time, the sampling tube is fixed only through a single connection point. Vibrations during deep drilling will be transmitted to the sampling tube, causing the rock core to collide with the cavity wall, further aggravating sample damage. Defects in core sampling adaptation: Cores from deep strata are usually at high temperatures. Traditional sampling methods do not include structures to maintain high temperatures. Temperature changes after the core is removed may damage the internal structure and affect the sample. Summary of the Invention

[0003] The purpose of this invention is to provide a deep rock sampling device and method for geological exploration, which solves the problems of insufficient support and protection for traditional sampling cores, easy wear of the cores, and inability to maintain the high temperature of the cores.

[0004] To achieve the above objectives, the present invention provides a deep rock sampling device for geological exploration, comprising a hollow drill rod, a drill bit at the bottom end of the hollow drill rod, a sampling cylinder inside the hollow drill rod, a sampling cavity inside the sampling cylinder, several sets of elastic support mechanisms for fixing the sampled rock core evenly arranged axially on the inner wall of the sampling cavity, the top end of the sampling cylinder being connected to the hollow drill rod via a non-synchronous rotation mechanism, the upper and lower parts of the sampling cylinder being connected to the hollow drill rod via symmetrically arranged sliding support mechanisms, a conical fixing seat for the sampled rock core to enter the sampling cavity being provided inside the bottom end of the hollow drill rod, and heating elements being arranged on the inner wall of the sampling cavity.

[0005] Preferably, the conical fixing seat is located above the drill bit and below the bottom opening of the sampling chamber. The conical fixing seat is detachably connected to the sampling cylinder. The interior of the conical fixing seat is provided with a conical opening, and the surface of the conical opening is provided with several drill teeth.

[0006] Preferably, the lower end of the conical opening is a conical inlet and the upper end is a conical outlet. The diameter of the conical inlet is larger than the diameter of the conical outlet, and the diameter of the conical outlet is the same as the inner diameter of the sampling chamber.

[0007] Preferably, the elastic support mechanism includes an alloy support head, a telescopic hole is provided inside the sampling chamber, the alloy support head is slidably disposed in the telescopic hole, the tail of the alloy support head is connected to the telescopic hole by a spring, the tail of the alloy support head is provided with a limiting block to prevent it from falling out of the telescopic hole, and the head of the alloy support head is covered with a contact buffer layer.

[0008] Preferably, the alloy support head is made of nickel-titanium shape memory alloy, the contact buffer layer is made of polytetrafluoroethylene reinforced ceramic coating, and the spring is made of high-temperature alloy spring.

[0009] Preferably, the asynchronous rotation mechanism includes a rotating column, which is connected to a fixed block via a bearing. The fixed block is detachably connected to the hollow drill rod. The bottom end of the rotating column is connected to the top end of the sampling cylinder. An anti-detachment block is provided at the top end of the rotating column. The bottom end of the anti-detachment block is slidably connected to the top end of the fixed block via several rolling balls.

[0010] Preferably, the sliding support mechanism includes a fixed column, a through hole is provided on the inner wall of the hollow drill rod, the fixed column is inserted into the through hole and locked to the through hole, the fixed column is detachably connected to the hollow drill rod, and the end of the fixed column near the sampling tube is connected to the sampling tube through the sliding support structure.

[0011] Preferably, the sliding support structure includes a support base, a pulley is rotatably provided at one end of the support base near the sampling cylinder, the support base is connected to the outer surface of the sampling cylinder through the pulley, and support rings are provided at both the upper and lower parts of the sampling cylinder, and the support base is connected to the support rings through an elastic support sliding unit. The elastic support sliding unit includes a support sleeve mounted on a support base, a support column slidably mounted on the support sleeve, a second spring mounted on the support column, a blocking block mounted on the support column, one end of the second spring connected to the end of the support sleeve near the support column, and the other end of the second spring connected to the blocking block, a second pulley rotatably mounted on the support column, the second pulley being located below the blocking block, and the support column being connected to the top or bottom end of the support ring via the second pulley.

[0012] Preferably, the heating element is an armored nickel-chromium heating wire, which is uniformly embedded along the circumference of the inner wall of the sampling chamber, and the heating element is arranged between two adjacent rows of expansion holes.

[0013] The present invention also provides a sampling method for a deep rock sampling device for geological exploration, comprising the following steps: Step 1, Device Pre-treatment and Assembly: The fixing block is fixedly connected to the hollow drill rod of the drilling equipment, and the bottom end of the rotating column on the fixing block is connected to the top end of the sampling tube; the fixing column is inserted into the through hole of the hollow drill rod and locked, so that the first pulley of the support seat is in contact with the outer surface of the sampling tube, and the second pulley is in contact with the support ring; the conical fixing seat is installed inside the bottom end of the hollow drill rod through a detachable structure. Step 2, Drilling Positioning and Rock Breaking Preparation: The drill bit is driven by the hollow drill pipe to drill down to the target sampling depth until the drill bit reaches the target formation depth. Step 3, Core Guiding and Entry into the Sampling Chamber: The drill bit breaks the rock to form a core column. The core column moves upward to the conical inlet of the conical fixing seat. The drill teeth on the surface of the conical opening trim the irregular rock core, eliminating surface protrusions and sharp edges. Under the axial thrust of the drill rod breaking the rock, the core column moves upward along the gradual structure of the conical opening and enters the sampling chamber through the conical outlet. During the insertion process, the core column compresses the alloy support head. As the spring contracts, the alloy support head adapts to the surface of the core, forming a fully enclosed elastic fixation. Step 4, Core-assisted fixation and environmental adaptation: Once the core column is fully inserted into the sampling chamber, the heating element is activated to raise the temperature of the inner wall of the sampling chamber to the sampling ambient temperature, thus maintaining the core in its original position. Step 5: Sampling cylinder lifting and device recovery: The drilling equipment is started, and the entire sampling device is lifted upwards by the hollow drill rod. The lifting stops when the sampling device is completely lifted out of the ground. Step 6, Core extraction and device repositioning: Disassemble the conical mounting base, remove the rock core, clean the inner wall of the sampling chamber, inspect all components, and reinstall the conical mounting base in its original position to prepare for the next sampling.

[0014] The advantages and positive effects of the deep rock sampling device and sampling method for geological exploration described in this invention are as follows: 1. Reliable and non-destructive core fixation: The elastic support mechanism uses an alloy support head made of nickel-titanium shape memory alloy, which has excellent elasticity and high temperature resistance. Combined with a contact buffer layer with polytetrafluoroethylene reinforced ceramic coating, it can avoid rigid contact and damage to the core, and resist the corrosion of organic solvents. The high-temperature alloy spring ensures that it remains elastic even in the deep high-temperature environment, realizes adaptive clamping of cores of different diameters, improves fixation stability, and reduces the damage rate of the core surface. 2. Smooth and unobstructed entry of rock cores: The conical nozzle of the conical fixing seat adopts a gradual structure with a large inlet and a small outlet. The diameter of the conical outlet is consistent with the inner diameter of the sampling chamber, achieving precise matching of the rock core diameter. The drill teeth on the surface of the conical nozzle can slightly trim irregular rock cores, eliminate protrusions and sharp edges, further reduce entry resistance, and improve the sampling success rate. 3. Minimal core wear and vibration damage: The asynchronous rotation mechanism achieves relatively independent movement between the sampling cylinder and the hollow drill rod through bearings and ball bearings. When the drill rod rotates to break the rock, the sampling cylinder remains stationary, avoiding rotational friction between the core and the inner wall of the sampling chamber, thus reducing core wear. The sliding support mechanism adopts a double sliding structure with pulley one and pulley two, combined with the elastic buffer of spring two, which can offset the radial and axial vibrations of deep drilling. 4. Adaptable to high-temperature environments: Armored nickel-chromium heating wires are evenly distributed along the inner wall of the sampling chamber to maintain the high temperature state during core extraction, ensuring the core is extracted intact; at the same time, nickel-titanium shape memory alloy, high-temperature alloy spring, and polytetrafluoroethylene coating are all suitable for deep high-temperature, high-pressure, and organic solvent environments, meeting the sampling requirements at depths of 1-10km. 5. Convenient and efficient sampling operation: The conical fixing seat, fixing block and fixing column are detachable, which facilitates the assembly, maintenance and core extraction of the device; the whole sampling process does not require complicated manual intervention, and the core entry, fixing and lifting are fully automated, which improves sampling efficiency.

[0015] The technical solution of the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. Attached Figure Description

[0016] Figure 1 This is a cross-sectional view of an embodiment of a deep rock sampling device for geological exploration according to the present invention; Figure 2 This is a schematic diagram of the hollow drill rod structure of an embodiment of a deep rock sampling device for geological exploration according to the present invention; Figure 3 This is a schematic diagram of the sampling cylinder structure of an embodiment of a deep rock sampling device for geological exploration according to the present invention; Figure 4 This is a schematic diagram of the elastic support mechanism of an embodiment of a deep rock sampling device for geological exploration according to the present invention; Figure 5 This is a schematic diagram of the asynchronous rotation mechanism of an embodiment of a deep rock sampling device for geological exploration according to the present invention; Figure 6 This is a schematic diagram of the sliding support mechanism of an embodiment of a deep rock sampling device for geological exploration according to the present invention; Figure 7 This is a schematic diagram showing the distribution of heating elements in an embodiment of a deep rock sampling device for geological exploration according to the present invention.

[0017] Figure label: 1. Hollow drill rod; 2. Drill bit; 3. Sampling cylinder; 4. Sampling chamber; 5. Conical fixed seat; 501. Conical inlet; 502. Conical outlet; 503. Drill teeth; 6. Elastic support mechanism; 601. Alloy support head; 602. Telescopic hole; 603. Spring 1; 604. Limiting block; 605. Contact buffer layer; 7. Non-synchronous rotation mechanism; 701. Rotating column; 702. Anti-detachment block; 703. Rolling ball; 704. Fixed block; 705. Bearing; 8. Sliding support mechanism; 801. Fixed column; 802. Support seat; 803. Pulley 1; 804. Support ring; 805. Support sleeve; 806. Support column; 807. Spring 2; 808. Blocking block; 809. Pulley 2; 9. Heating element. Detailed Implementation

[0018] In the description of this invention, it should be noted that the terms "upper," "lower," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship commonly used when the product is in use. They are used only for the convenience of describing the invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the invention. In the description of this invention, it should also be noted that, unless otherwise explicitly specified and limited, the terms "set," "install," and "connect" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal communication between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0019] In this application, unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains. In case of any inconsistency, the meaning set forth in this specification or derived from the content described herein shall prevail. Furthermore, the terminology used herein is for the purpose of describing embodiments of this application only and is not intended to limit the scope of this application.

[0020] The embodiments of the present invention will now be described in detail with reference to the accompanying drawings.

[0021] Example: like Figure 1 , Figure 2 , Figure 3As shown, the present invention discloses a deep rock sampling device for geological exploration, comprising a hollow drill rod 1, with a drill bit 2 disposed at the bottom end of the hollow drill rod 1. A sampling cylinder 3 is disposed inside the hollow drill rod 1, and a sampling chamber 4 is disposed inside the sampling cylinder 3. The sampling cylinder 3 is integrally molded from titanium alloy and carbon fiber reinforced composite material, balancing structural strength and lightweight requirements. Its overall weight is 40% lighter than that of a traditional steel sampling cylinder 3, with a maximum temperature resistance of 600℃ and a pressure resistance rating of ≥200MPa, making it suitable for sampling environments at depths of 1-10km. The inner diameter of the sampling chamber 4 is designed to be 30-100mm according to sampling requirements, and its length can be customized within the range of 0.5-2m. The inner wall is honed to ensure smooth entry of the rock core.

[0022] like Figure 1 As shown, a conical fixing seat 5 for core sampling is installed inside the bottom end of the hollow drill rod 1, which is used to guide the core sample into the sampling chamber 4. The conical fixing seat 5 is located above the drill bit 2 and below the bottom opening of the sampling chamber 4, and is detachably connected to the sampling tube 3. The conical fixing seat 5 has a conical opening inside, and several drill teeth 503 are provided on the surface of the conical opening. The lower end of the conical opening is a conical inlet 501, and the upper end is a conical outlet 502. The diameter of the conical inlet 501 is larger than the diameter of the conical outlet 502. The diameter of the conical outlet 502 is the same as the inner diameter of the sampling chamber 4. As a key component for core guidance and diameter adaptation, the conical fixing seat 5 is made of high-strength wear-resistant alloy steel and its surface is nitrided (hardness HRC≥60), possessing excellent wear resistance and impact resistance. It is detachably connected to the bottom end of the sampling tube 3 by 4-6 sets of bolts evenly distributed around the circumference, which is convenient for disassembly and facilitates subsequent maintenance and cleaning of residual debris from the drill teeth 503. The conical fixing seat 5 has a gradually tapered opening inside, with the conical inlet 501 at a 45° angle to the axis and the conical outlet 502 at a 15° angle to the axis, forming a gradual structure of "large inlet, small outlet" to achieve a smooth transition in the core diameter. The diameter of the conical inlet 501 is 5-10 mm larger than that of the conical outlet 502, and the diameter of the conical outlet 502 is exactly the same as the inner diameter of the sampling chamber 4 (error ≤ 0.1 mm), ensuring that the core can accurately enter the sampling chamber 4 after fitting. The inner wall of the conical opening has 8-12 carbide drill teeth 503 evenly distributed in a spiral shape. The drill teeth 503 are 2 mm high and 5 mm apart, which can not only slightly trim the surface protrusions and edges of irregular cores, but also play a guiding role to prevent the core from shifting and getting stuck in the conical opening.

[0023] like Figure 1 , Figure 4As shown, several sets of elastic support mechanisms 6 for fixing the sampled rock core are uniformly arranged axially on the inner wall of the sampling chamber 4. The elastic support mechanism 6 includes an alloy support head 601. An expansion hole 602 is provided inside the sampling chamber 4. The alloy support head 601 is slidably disposed within the expansion hole 602. The tail of the alloy support head 601 is connected to the expansion hole 602 via a spring 603. A limiting block 604 is provided at the tail of the alloy support head 601 to prevent it from falling out of the expansion hole 602. The head of the alloy support head 601 is covered with a contact buffer layer 605. The alloy support head 601 is made of nickel-titanium shape memory alloy, possessing excellent shape memory effect and elastic recovery capability. Within a temperature range of -20~300℃, its elastic modulus is stable at 100-110 GPa, and its recovery rate after deformation reaches 100%. The support head has a cylindrical structure with a hemispherical head (radius 5mm) to avoid sharp contact that could damage the surface of the rock core. Spring 603 is a high-temperature alloy spring (made of Inconel 718), with a wire diameter of 1.5mm, a free length of 20mm, and an elastic modulus of 200GPa. In a working environment of -20~300℃, its elastic decay is ≤5% after long-term use. It can provide an adaptive clamping force of 0.3-1MPa, adapting to the fixing requirements of rock cores of different diameters. The contact buffer layer 605 uses a polytetrafluoroethylene (PTFE) reinforced ceramic coating, which is laminated to the head of the alloy support head 601 via plasma spraying. The coating thickness is 0.5-1mm, and the bonding strength is ≥50MPa. This coating combines the self-lubricating properties of PTFE (friction coefficient ≤0.02) with the high-temperature resistance and corrosion resistance of ceramics, preventing hard contact damage between the rock core and the support head, and resisting the erosion of organic solvents (such as DMF and NMP) within the sampling chamber 4.

[0024] like Figure 1 , Figure 5As shown, the top end of the sampling cylinder 3 is connected to the hollow drill rod 1 via a asynchronous rotation mechanism 7. The asynchronous rotation mechanism 7 includes a rotating column 701, which is connected to a fixed block 704 via a bearing 705. The fixed block 704 is detachably connected to the hollow drill rod 1 (fixed to the inner wall of the hollow drill rod 1 by multiple sets of bolts). The bottom end of the rotating column 701 is connected to the top end of the sampling cylinder 3, and an anti-detachment block 702 is provided at the top end of the rotating column 701. The bottom end of the anti-detachment block 702 is slidably connected to the top end of the fixed block 704 via several rolling balls 703 (the rolling balls 703 are silicon carbide ceramic rolling balls 703, embedded in the anti-detachment block 702 and rotatable on the anti-detachment block 702). Bearing 705 is a high-precision deep groove ball bearing with an IP67 sealing rating, a temperature resistance of ≥200℃, and a radial clearance of ≤0.02mm, ensuring that the sampling cylinder 3 remains stable and stationary even when the drill pipe rotates at high speed, with a rotational resistance torque of ≤5N·m. The rotating column 701 is made of titanium alloy, with a diameter of 50-80mm and a length of 100-150mm. Its bottom end is bolted to the top of the sampling cylinder 3 via a flange, and a locating pin is added at the connection point, with a coaxiality error of ≤0.05mm. The top of the rotating column 701 is fixedly connected to the anti-detachment block 702, resulting in a high overall structural strength capable of withstanding the weight load of the sampling cylinder 3 and the rock core.

[0025] like Figure 1 , Figure 6 As shown, the upper and lower parts of the sampling cylinder 3 are connected to the hollow drill rod 1 via symmetrically arranged sliding support mechanisms 8. The sliding support mechanism 8 includes a fixed column 801. A through hole is provided on the inner wall of the hollow drill rod 1, and the fixed column 801 is inserted into the through hole and locked in place. The fixed column 801 is detachably connected to the hollow drill rod 1, and the end of the fixed column 801 near the sampling cylinder 3 is connected to the sampling cylinder 3 via the sliding support structure. The sliding support structure includes a support base 802, and a pulley 803 is rotatably arranged at the end of the support base 802 near the sampling cylinder 3. The support base 802 is connected to the outer surface of the sampling cylinder 3 via the pulley 803. Support rings 804 are provided at both the upper and lower parts of the sampling cylinder 3, and the support base 802 is connected to the support rings 804 via an elastic support sliding unit. The elastic support sliding unit includes a support sleeve 805 disposed on the support base 802, and a support column 806 is slidably disposed on the support sleeve 805. A second spring 807 is fitted onto the support column 806, and a blocking block 808 is provided on the support column 806. One end of the second spring 807 is connected to the end of the support sleeve 805 near the support column 806, and the other end of the second spring 807 is connected to the blocking block 808. A second pulley 809 is rotatably mounted on the support column 806, located below the blocking block 808. The support column 806 is connected to the top or bottom end of the support ring 804 via the second pulley 809.

[0026] like Figure 7As shown, heating elements 9 are arranged on the inner wall of the sampling chamber 4. The heating elements 9 are armored nickel-chromium heating wires, evenly embedded along the circumference of the inner wall of the sampling chamber 4, and positioned between adjacent rows of telescopic holes 602. Four to six groups of heating elements 9 are evenly embedded along the circumference of the inner wall of the sampling chamber 4, each group having a heating wire power of 50W. They are axially positioned between adjacent rows of telescopic holes 602, ensuring that the telescopic movement of the elastic support mechanism 6 is not affected while achieving uniform heating of the inner wall of the sampling chamber 4. The heating elements 9 are fixed to a dedicated groove on the inner wall of the sampling chamber 4 using high-temperature resistant ceramic sleeves. The ceramic sleeves fit tightly against the heating wires, providing high thermal conductivity and also serving as insulation and protection.

[0027] The sampling method of the deep rock sampling device for geological exploration according to the present invention includes the following steps: Step 1, Device Pre-treatment and Assembly: The fixing block 704 is fixedly connected to the hollow drill rod 1 of the existing drilling equipment (bolted connection). The bottom end of the rotating column 701 on the fixing block 704 is connected to the top end of the sampling cylinder 3 (bolted connection). The fixing block 704, bearing 705, rotating column 701, rolling ball 703, and anti-detachment block 702 are integrally set. The fixing column 801 is inserted into the through hole of the hollow drill rod 1 and locked (bolted lock), so that the pulley 803 of the support seat 802 is in contact with the outer surface of the sampling cylinder 3, and the pulley 809 is in contact with the support ring 804. The conical fixing seat 5 is installed inside the bottom end of the hollow drill rod 1 through a detachable structure (bolted connection), ensuring that the conical outlet 502 is aligned with the bottom opening of the sampling chamber 4. Step 2, Drilling Positioning and Rock Breaking Preparation: The hollow drill rod 1 drives the drill bit 2 to drill down to the target sampling depth. During the drilling process, the sliding support mechanism 8 balances the vibration of the drill rod in real time and keeps the sampling cylinder 3 stable until the drill bit 2 reaches the target formation depth. Step 3, Core Guiding and Entry into Sampling Chamber 4: Drill bit 2 breaks the rock to form a core column. The core column moves upward to the conical inlet 501 of the conical fixing seat 5. The drill teeth 503 on the surface of the conical opening slightly trim the irregular rock core (the drill teeth 503 can also assist in the fracture of the rock core after sampling, improving sampling efficiency), eliminating surface protrusions and edges. Under the axial thrust of the drill rod breaking the rock, the core column moves upward along the gradual structure of the conical opening and enters the sampling chamber 4 through the conical outlet 502. During the insertion process, the core column compresses the alloy support head 601, the spring 603 retracts, and the alloy support head 601 adaptively conforms to the surface of the core, forming a fully enclosed elastic fixation to prevent the core from shaking (a hydraulic cylinder can be installed at the top of the sampling chamber 4 to facilitate the subsequent removal of the core; the hydraulic rod of the hydraulic cylinder is connected to the removal block, and a high-temperature resistant elastic pad is installed at the end of the removal block that contacts the core to protect the top of the core column from damage). Step 4, Core-assisted fixation and environmental adaptation: After the core rod is fully inserted into the sampling chamber 4, keep the drill rod stationary for 30-60 seconds to ensure that the elastic support mechanism 6 fully clamps the core; start the heating element 9 and raise the temperature of the inner wall of the sampling chamber 4 to the sampling environment temperature through the existing temperature control system (a temperature sensor is set in the sampling chamber 4 to monitor the temperature) to keep the core in place. Step 5: Sampling cylinder 3 is lifted and the device is retrieved. The drilling equipment is started, and the hollow drill rod 1 drives the entire sampling device upward. During the lifting process, the asynchronous rotation mechanism 7 ensures that the sampling cylinder 3 remains stationary, and the spring 807 of the sliding support mechanism 8 continuously buffers vibrations to prevent core collisions. The elastic support mechanism 6 always clamps the core to prevent it from shifting or falling off during lifting. Lifting stops when the sampling device is completely lifted out of the ground. Step 6, Core extraction and device repositioning: Disassemble the conical fixing seat 5, press down with the hydraulic cylinder to push out the rock core, clean the inner wall of the sampling chamber 4, check all components, and reinstall the conical fixing seat 5 in its original position to prepare for the next sampling.

[0028] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit them. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can still be made to the technical solutions of the present invention, and these modifications or equivalent substitutions cannot cause the modified technical solutions to deviate from the spirit and scope of the technical solutions of the present invention.

Claims

1. A deep rock sampling device for geological exploration, comprising a hollow drill rod, wherein a drill bit is disposed at the bottom end of the hollow drill rod, characterized in that: A sampling tube is installed inside the hollow drill rod, and a sampling cavity is installed inside the sampling tube. Several sets of elastic support mechanisms for fixing the sampled rock core are evenly arranged axially on the inner wall of the sampling cavity. The top of the sampling tube is connected to the hollow drill rod through a non-synchronous rotation mechanism. The upper and lower parts of the sampling tube are connected to the hollow drill rod through symmetrically arranged sliding support mechanisms. A conical fixing seat for the sampled rock core to enter the sampling cavity is installed inside the bottom end of the hollow drill rod. Heating elements are arranged on the inner wall of the sampling cavity.

2. The geological exploration deep rock sampling device according to claim 1, characterized in that: The conical fixing seat is located above the drill bit and below the bottom opening of the sampling chamber. The conical fixing seat is detachably connected to the sampling cylinder. The conical fixing seat has a conical opening inside, and the surface of the conical opening has several drill teeth.

3. The geological exploration deep rock sampling device according to claim 2, characterized in that: The lower end of the conical opening is the conical inlet, and the upper end is the conical outlet. The diameter of the conical inlet is larger than the diameter of the conical outlet, and the diameter of the conical outlet is the same as the inner diameter of the sampling chamber.

4. The geological exploration deep rock sampling device according to claim 1, characterized in that: The elastic support mechanism includes an alloy support head, a telescopic hole is provided inside the sampling chamber, the alloy support head is slidably disposed in the telescopic hole, the tail of the alloy support head is connected to the telescopic hole by a spring, the tail of the alloy support head is provided with a limiting block to prevent it from falling out of the telescopic hole, and the head of the alloy support head is covered with a contact buffer layer.

5. The geological exploration deep rock sampling device according to claim 4, characterized in that: The alloy support head is made of nickel-titanium shape memory alloy, the contact buffer layer is made of polytetrafluoroethylene reinforced ceramic coating, and the spring is a high-temperature alloy spring.

6. The geological exploration deep rock sampling device according to claim 1, characterized in that: The asynchronous rotation mechanism includes a rotating column, which is connected to a fixed block via a bearing. The fixed block is detachably connected to a hollow drill rod. The bottom end of the rotating column is connected to the top end of the sampling cylinder. An anti-detachment block is provided at the top end of the rotating column, and the bottom end of the anti-detachment block is slidably connected to the top end of the fixed block via several rolling balls.

7. The geological exploration deep rock sampling device according to claim 1, characterized in that: The sliding support mechanism includes a fixed column, and a through hole is provided on the inner wall of the hollow drill rod. The fixed column is inserted into the through hole and locked to the through hole. The fixed column and the hollow drill rod are detachably connected. The end of the fixed column near the sampling tube is connected to the sampling tube through the sliding support structure.

8. The geological exploration deep rock sampling device according to claim 7, characterized in that: The sliding support structure includes a support base, a pulley is rotatably provided at one end of the support base near the sampling cylinder, the support base is connected to the outer surface of the sampling cylinder through the pulley, and support rings are provided at the upper and lower parts of the sampling cylinder. The support base is connected to the support rings through an elastic support sliding unit. The elastic support sliding unit includes a support sleeve mounted on a support base, a support column slidably mounted on the support sleeve, a second spring mounted on the support column, a blocking block mounted on the support column, one end of the second spring connected to the end of the support sleeve near the support column, and the other end of the second spring connected to the blocking block, a second pulley rotatably mounted on the support column, the second pulley being located below the blocking block, and the support column being connected to the top or bottom end of the support ring via the second pulley.

9. The geological exploration deep rock sampling device according to claim 4, characterized in that: The heating element uses armored nickel-chromium heating wire, which is uniformly embedded along the circumference of the inner wall of the sampling chamber. The heating element is arranged between two adjacent rows of expansion holes.

10. A sampling method for a deep rock sampling device for geological exploration according to any one of claims 1-9, characterized in that, Includes the following steps: Step 1, Device Pre-treatment and Assembly: The fixing block is fixedly connected to the hollow drill rod of the drilling equipment, and the bottom end of the rotating column on the fixing block is connected to the top end of the sampling tube; the fixing column is inserted into the through hole of the hollow drill rod and locked, so that the first pulley of the support seat is in contact with the outer surface of the sampling tube, and the second pulley is in contact with the support ring; the conical fixing seat is installed inside the bottom end of the hollow drill rod through a detachable structure. Step 2, Drilling Positioning and Rock Breaking Preparation: The drill bit is driven by the hollow drill pipe to drill down to the target sampling depth until the drill bit reaches the target formation depth. Step 3, Core Guiding and Entry into the Sampling Chamber: The drill bit breaks the rock to form a core column. The core column moves upward to the conical inlet of the conical fixing seat. The drill teeth on the surface of the conical opening trim the irregular rock core, eliminating surface protrusions and sharp edges. Under the axial thrust of the drill rod breaking the rock, the core column moves upward along the gradual structure of the conical opening and enters the sampling chamber through the conical outlet. During the insertion process, the core column compresses the alloy support head. As the spring contracts, the alloy support head adapts to the surface of the core, forming a fully enclosed elastic fixation. Step 4, Core-assisted fixation and environmental adaptation: Once the core column is fully inserted into the sampling chamber, the heating element is activated to raise the temperature of the inner wall of the sampling chamber to the sampling ambient temperature, thus maintaining the core in its original position. Step 5: Sampling cylinder lifting and device recovery: The drilling equipment is started, and the entire sampling device is lifted upwards by the hollow drill rod. The lifting stops when the sampling device is completely lifted out of the ground. Step 6, Core extraction and device repositioning: Disassemble the conical mounting base, remove the rock core, clean the inner wall of the sampling chamber, inspect all components, and reinstall the conical mounting base in its original position to prepare for the next sampling.

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