Hydraulic transmission structure, geological drilling device and method of use

Abstract

This invention discloses a hydraulic transmission structure, a geological drilling device, and a method of use, relating to the field of hydraulic transmission. The hydraulic transmission mechanism is equipped with a gear transmission component and an elastic switching assembly. A first seal and a second seal are provided on the circumferential side of the piston. When the connecting rod is retracted to its minimum extension, the elastic switching assembly resets, drives the gear transmission component to rotate forward, and pre-drives the extrusion plate to compress the air bladder, pre-establishing a seal by radially expanding the second seal and increasing the contact force with the inner wall of the cylinder. When the connecting rod is in the retraction phase, the elastic switching assembly drives the gear transmission component to rotate in the opposite direction, and the extrusion plate releases the air bladder, achieving radial contraction of the second seal and reducing friction with the inner wall of the cylinder. This solves the problem that existing expansion seals or pressure adaptive seals cannot pre-establish a seal before pressure increases or timely reduce friction at the start of the return stroke.

Description

Technical Field

[0001] This invention relates to the technical field of hydraulic transmission, and more particularly to a hydraulic transmission structure, a geological drilling device, and a method of using it. Background Technology

[0002] During the construction of deep underground tunnels, the uncertainty of the strata ahead of the tunnel face directly affects construction safety, support parameters, and construction organization. Failure to identify adverse geological bodies such as fault fracture zones, water-rich structures, karst caves, and weak interlayers in advance can easily lead to risks such as water and mud inrushes, collapses, equipment jamming, and over- or under-excavation. Existing projects typically employ a comprehensive approach using geological sketching, TSP (Through-Slip Perimeter), ground-penetrating radar, advanced horizontal drilling, and core sampling analysis. Horizontal drilling provides direct samples, while ground-penetrating radar provides continuous anomalous reflection information; combining these methods improves the reliability of advance prediction for deep underground tunnels. However, this combination of detection methods primarily addresses the issue of geological information acquisition and cannot directly resolve the hydraulic sealing resistance problem encountered by the drilling actuator during frequent loading and retrieval processes.

[0003] However, when advanced drilling rigs operate in hard rock, fractured rock masses, or water-rich soft zones, the feed resistance of the drill bit changes significantly, requiring the hydraulic feed mechanism to possess both high sealing reliability and low motion resistance. Traditional hydraulic cylinders typically require a large pre-tight contact force between the piston seal and the cylinder wall to reduce leakage during high-pressure loading; however, during unloading and recovery, this large contact force translates into additional frictional resistance, leading to increased hydraulic pump load, accelerated seal wear, and affecting stroke control accuracy during long-distance cyclic drilling.

[0004] Existing expansion seals or pressure-adaptive seal structures mostly rely on hydraulic oil pressure, back pressure chamber pressure, or sealing chamber pressure to deform the sealing ring. Although they can adjust the sealing force to some extent with pressure changes, their adjustment usually lags behind the oil pressure build-up process, and the timing of the sealing chamber pressurization is still affected by the hydraulic pressure itself. In other words, this type of structure solves the problem of "how to enhance the seal after the pressure increases," but does not solve the problem of "how to pre-establish the seal before the pressure increases and how to reduce friction in time at the start of the return stroke." When the drilling load changes abruptly or the connecting rod stroke switches frequently, the establishment and release of the sealing force cannot match the drilling action in time, which can easily lead to micro-leakage in the initial loading stage, excessive friction in the recovery stage, and accumulation of feed position control errors. Therefore, there is an urgent need for a hydraulic sealing transmission structure that can mechanically switch in advance according to the connecting rod stroke position and direction, and to apply it to deep underground tunnel advanced drilling equipment with integrated radar detection. Summary of the Invention

[0005] Purpose of the invention: The purpose of this invention is to provide a hydraulic transmission structure, a geological drilling device and a method of use, which solves the technical problem that existing expansion seal or pressure adaptive seal structures cannot achieve pre-establishment of a seal before pressure rise and timely reduction of friction at the start of the return stroke.

[0006] Technical solution: A hydraulic transmission mechanism includes a cylinder, a piston disposed within the cylinder and capable of reciprocating along the axial direction of the cylinder, and a connecting rod connected to the piston and passing through the cylinder. A first seal and a variable-diameter sealing unit are disposed on the circumferential side of the piston. The first seal is slidably connected to the inner wall of the cylinder. The variable-diameter sealing unit includes a second seal, the second seal having an annular cavity formed therein that, when filled with a compressed medium, can drive the second seal to expand radially outward and increase the contact force with the inner wall of the cylinder. The cylinder is provided with an elastic switching component for switching the sealing force of the second seal according to the position and direction of the connecting rod stroke. A compression assembly is provided on the piston. The compression assembly includes an air bladder communicating with the annular cavity and containing a compression medium, a compression plate for squeezing or releasing the air bladder, and a gear transmission component pulverizedly connected to the compression plate. The gear transmission component and the elastic switching assembly are adapted to each other. When the connecting rod is in the extended stage, the compression plate keeps squeezing the air bladder. When the connecting rod is in the retracted stage, the elastic switching assembly drives the gear transmission component to rotate in the opposite direction, and the compression plate releases the air bladder. When the connecting rod is retracted to the minimum extension amount, the elastic switching assembly resets, and the elastic switching assembly drives the gear transmission component to rotate in the forward direction, pre-driving the compression plate to squeeze the air bladder. The hydraulic transmission mechanism of this application is provided with a gear transmission component and an elastic switching component, and a first seal and a second seal are provided on the circumferential side of the piston. When the connecting rod is retracted to the minimum extension, the elastic switching component resets, drives the gear transmission component to rotate forward, and drives the extrusion plate to squeeze the air bladder in advance, thereby pre-expanding the second seal radially and increasing the contact force between it and the inner wall of the cylinder, thus pre-establishing a seal. When the connecting rod is in the retraction stage, the elastic switching component drives the gear transmission component to rotate in the reverse direction, and the extrusion plate releases the air bladder, thereby achieving radial contraction of the second seal and reducing the friction between it and the inner wall of the cylinder. This solves the technical problem that existing expansion seals or pressure adaptive seal structures cannot achieve pre-establishment of a seal before pressure rise and timely reduction of friction at the start of the return stroke.

[0007] Preferably, at least two elastic switching components and at least two gear transmission components are arranged circumferentially along the connecting rod, with each elastic switching component and gear transmission component corresponding to the other. Arranging at least two elastic switching components and at least two gear transmission components circumferentially along the connecting rod ensures stable compression or release of the air bladder on the piston, thus ensuring the stability of the entire mechanism.

[0008] Preferably, the gear transmission component includes a support platform, a threaded sleeve, a gear, a lead screw, and a guide shaft. The support platform is fixedly mounted on the piston, the threaded sleeve is rotatably mounted on the support platform, the gear is coaxially and fixedly connected to the threaded sleeve, and the lead screw is threadedly connected to the threaded sleeve. One end of the lead screw is connected to the extrusion plate, and the other end is provided with a guide shaft that passes through the support platform and provides sliding guidance. The guide shaft restricts the lead screw to rotate synchronously with the threaded sleeve. When the threaded sleeve rotates, the lead screw can drive the extrusion plate to move axially closer to or away from the airbag. The sector-shaped rack plate drives the gear and the threaded sleeve to rotate, causing the extrusion plate to move away from or closer to the airbag, thereby releasing or compressing to increase the pressure in the annular cavity.

[0009] Preferably, the elastic switching assembly includes a follower sleeve, a sector-shaped rack plate, a cylindrical spring, and a switching groove. The follower sleeve is rotatably mounted on the connecting rod. The sector-shaped rack plate is connected to the follower sleeve and meshes with a gear. One end of the cylindrical spring is connected to the follower sleeve, and the other end is connected to the piston. The switching groove is located on the outer circumferential wall of the follower sleeve. The cylinder body has a convex shaft that matches the switching groove and controls whether the follower sleeve can rotate. One end of the cylindrical spring is connected to the follower sleeve, and the other end is connected to the piston, used to apply a restoring torsional tendency to the follower sleeve. The switching groove and the convex shaft are provided to control whether the follower sleeve can rotate.

[0010] Preferably, the switching groove includes a first straight groove, an arc-shaped groove, a second straight groove, a spiral groove, and an extension. The first straight groove and the second straight groove extend axially along the follower sleeve. One end of the first straight groove and the second straight groove are connected by the arc-shaped groove, and the other end is connected by the spiral groove. The extension is formed at the end of the first straight groove near the spiral groove. When the connecting rod extends, the cam shaft moves along the first straight groove, the follower sleeve does not rotate, and the second seal remains in an expanded sealing state. When the connecting rod retracts, the cam shaft enters the spiral groove. The cooperation between the cam shaft and the spiral groove forces the follower sleeve to rotate. The fan-shaped rack plate drives the gear and the threaded sleeve to rotate in the opposite direction, causing the extrusion plate to release the airbag. When the connecting rod retracts to the minimum extension amount, the cam shaft moves to the return end through the second straight groove. The cylindrical spring releases its stored energy and drives the follower sleeve to rotate. The fan-shaped rack plate drives the gear in the forward direction, causing the extrusion plate to re-extrude the airbag.

[0011] Preferably, a one-way guide plate is provided at the position where the spiral groove connects to the first straight groove. The one-way guide plate is mounted on the follower sleeve via a rotating shaft, and a torsion spring is provided on the rotating shaft. When the connecting rod extends, the cam shaft moves along the first straight groove, the follower sleeve does not rotate, and the second seal remains in an expanded sealing state. When the cam shaft reaches the extension, the one-way guide plate is pushed open. When the connecting rod retracts, the one-way guide plate guides the cam shaft into the spiral groove. The spiral groove and the cam shaft cooperate to replace the linear motion of the connecting rod with the rotational motion of the follower sleeve. This ensures that when the connecting rod retracts, the cooperation between the cam shaft and the spiral groove forces the follower sleeve to rotate, and the fan-shaped rack plate drives the gear and the threaded sleeve to rotate in the opposite direction, causing the extrusion plate to release the airbag.

[0012] Preferably, the follower sleeve has an annular connecting portion inside, and the connecting rod has an annular connecting groove. The annular connecting portion is rotatably connected to the annular connecting groove. That is, the follower sleeve is sleeved on the connecting rod, and the annular connecting portion inside the follower sleeve is rotatably engaged with the annular connecting groove on the connecting rod, so that the follower sleeve can move axially with the connecting rod, and at the same time can rotate circumferentially relative to the connecting rod.

[0013] Preferably, the pitch radius of the gear is smaller than that of the sector rack. This is because when the sector rack rotates through a small angle with the follower sleeve, the gear and threaded sleeve can achieve a larger rotational output, thereby increasing the axial displacement of the extrusion plate. The threaded transmission pair also has a certain labor-saving and self-locking effect, which can reduce the load of switching actions and reduce the possibility of the extrusion plate retraction caused by back pressure in the annular cavity.

[0014] Preferably, the piston has a second annular groove on its circumferential side, and the second seal is fitted inside the second annular groove. The annular cavity is either continuously arranged along the circumference of the second seal or segmented and interconnected. The second seal has an annular cavity inside, which can be continuously arranged along the circumference of the second seal or composed of multiple interconnected cavities. When the annular cavity is filled with a compressed medium, the second seal exhibits a radial outward expansion tendency, increasing the contact force between its outer circumferential surface and the inner wall of the cylinder, thereby improving the sealing reliability under high-pressure loading.

[0015] Preferably, the sidewall of the annular cavity has a bend for elastic expansion when the annular cavity is pressurized, thereby reducing the amount of medium required to drive the second seal to expand radially outward. The bend is equivalent to an expandable elastic deformation zone. When the annular cavity is pressurized, the bend deforms preferentially and pushes the second seal to expand radially outward, so that the second seal obtains a significant change in sealing force with a small change in the amount of medium.

[0016] Preferably, first annular grooves are respectively provided on both sides of the second annular groove, and the first seal is disposed within the first annular groove. The piston is located on both sides of the second annular groove, each with a first annular groove, and the first seal is disposed within the first annular groove. The first seal slides against the inner wall of the cylinder, providing a basic seal when the second seal is in its natural state or at low contact force, preventing air from entering the hydraulic system or causing significant hydraulic oil leakage. The two first seals provide a basic seal, while the second seal provides an enhanced seal during high-load drilling. The two first seals and the second seal together form a graded sealing structure.

[0017] Preferably, the piston is provided with a guiding channel, one end of which communicates with the annular cavity and the other end with the airbag. The airbag is mounted on the piston. When the airbag is squeezed by the compression plate, the medium inside the airbag enters the annular cavity through the guiding channel. When the compression plate moves away from the airbag, the medium in the annular cavity flows back to the airbag, causing the second seal to reset or reduce the adhesion force.

[0018] Preferably, the compression medium is an inert gas medium or a low-compressibility elastic medium. Using an inert gas medium or a low-compressibility elastic medium is to reduce the impact of temperature rise and repeated compression on the stability of the sealing state; the compression medium can also be nitrogen.

[0019] A geological drilling apparatus includes a frame, a main rod, a power mechanism, a detection drill bit, a wireline coring assembly, a ground-penetrating radar (GPR) detection assembly, and the aforementioned hydraulic transmission mechanism. The hydraulic transmission mechanism drives or adjusts the feed stroke of the main rod. The power mechanism drives the detection drill bit to rotate. The GPR detection assembly is positioned on the detection drill bit, the main rod, or near the drilling tip to detect surrounding rock ahead of the face of the borehole or geological anomalies around the borehole during drilling. The wireline coring assembly retrieves core samples after drilling to a predetermined depth. In this geological drilling apparatus, the hydraulic transmission mechanism can be installed between the frame and the main rod, or on the hydraulic actuator used to drive the detection drill bit feed. The power mechanism drives the detection drill bit to rotate and / or advance, and the wireline coring assembly retrieves core samples after drilling to a predetermined depth. The GPR detection assembly can be positioned on the detection drill bit, the front end of the main rod, or near the borehole tip to acquire radar echo data of the surrounding rock interface and anomalies during drilling.

[0020] Preferably, the ground-penetrating radar detection component includes a radar antenna, a radar signal transceiver module, an attitude or depth acquisition module, and a data processing module. The data processing module is configured to correlate radar echo data with drilling depth, drilling resistance, or core sampling information to form advanced geological identification results.

[0021] One method of use includes the following steps: S1. Arrange the drilling mechanism at the tunnel face or the location to be detected, and set the drilling direction, single feed depth and radar acquisition parameters. S2. Control the hydraulic transmission mechanism and the power mechanism to make the probe drill bit rotate in a set direction; before the connecting rod extends and bears the drilling load, the elastic switching component and the gear transmission component jointly drive the extrusion plate to pre-compress the air bag, thereby making the second seal in an expanded sealing state. S3. During the drilling process, the geological radar detection component is activated synchronously or in stages to collect radar echo data in front of the tunnel face or around the borehole, and to record the corresponding drilling depth and drilling conditions. S4. When the probe drill bit is rotated to a predetermined depth, the connecting rod is controlled to retract. The cooperation between the cam shaft and the spiral groove drives the follower sleeve to rotate, so that the extrusion plate releases the air bag and reduces the adhesion force between the second seal and the inner wall of the cylinder. S5. Repeat steps S2 to S4 until the predetermined detection depth is reached, and use the rope core sampling assembly to retrieve the sample. S6. Comprehensively compare the radar echo data, drilling parameters, and core information of samples taken from the wireline coring assembly to determine the location and extent of faults, fracture zones, water-rich areas, karst caves, or weak interlayers.

[0022] Preferably, in step S3, when an abnormal reflection interface appears in the radar echo or a sudden change occurs in the drilling resistance, the single feed depth is reduced and the radar sampling density is increased.

[0023] Beneficial effects: 1. The hydraulic transmission mechanism of this application is provided with a gear transmission component and an elastic switching component, and a first seal and a second seal are provided on the circumferential side of the piston. When the connecting rod is retracted to the minimum extension, the elastic switching component resets, drives the gear transmission component to rotate in the forward direction, and drives the extrusion plate to squeeze the air bag in advance, thereby pre-emptively expanding the second seal radially outward and increasing the contact force between it and the inner wall of the cylinder, thus pre-establishing a seal. When the connecting rod is in the retraction stage, the elastic switching component drives the gear transmission component to rotate in the reverse direction, and the extrusion plate releases the air bag, thereby achieving radial contraction of the second seal and reducing the friction between it and the inner wall of the cylinder.

[0024] 2. In this application, the piston has first annular grooves on both sides of the second annular groove, and a first seal is disposed within each of the first annular grooves. The first seal slides against the inner wall of the cylinder, providing a basic seal when the second seal is in its natural state or at low contact force, preventing air from entering the hydraulic system or causing significant leakage of hydraulic oil. The two first seals provide a basic seal, while the second seal provides an enhanced seal during high-load drilling. The two first seals and the second seal together form a graded sealing structure. Attached Figure Description

[0025] Figure 1 This is a schematic diagram of the hydraulic transmission mechanism of the present invention.

[0026] Figure 2 A cross-sectional view of the hydraulic transmission mechanism of the present invention. Figure 1 .

[0027] Figure 3 A cross-sectional view of the hydraulic transmission mechanism of the present invention. Figure 2 .

[0028] Figure 4 for Figure 3 Enlarged view of the structure at point A in the middle.

[0029] Figure 5 This is a cross-sectional view of the connection between the piston and connecting rod in the hydraulic transmission mechanism of the present invention.

[0030] Figure 6 for Figure 5 Enlarged view of the structure at point B.

[0031] Figure 7 This is a cross-sectional view of the cylinder body in the hydraulic transmission mechanism of the present invention.

[0032] Figure 8 This is a schematic diagram showing the connection of the connecting rod, piston, compression assembly, and elastic switching assembly in the hydraulic transmission mechanism of the present invention.

[0033] Figure 9 for Figure 8 Enlarged view of the structure at point C.

[0034] Figure 10 This is a schematic diagram of the connection of the compression component in the hydraulic transmission mechanism of the present invention.

[0035] In the diagram: 1. Cylinder body; 101. Cam shaft; 2. Piston; 201. First annular groove; 202. Second annular groove; 203. Conducting channel; 3. Connecting rod; 301. Annular connecting groove; 4. First seal; 5. Second seal; 501. Annular cavity; 502. Bending part; 6. Airbag; 7. Follower sleeve; 701. Annular connecting part; 702. First straight groove; 703. Arc groove; 704. Second straight groove; 705. Spiral groove; 706. Extension part; 8. Sector rack plate; 9. Support platform; 10. Threaded sleeve; 11. Gear; 12. Lead screw; 13. Guide shaft; 14. Extrusion plate; 15. Columnar spring; 16. One-way guide plate. Detailed Implementation

[0036] To make the technical solution of the present invention clearer, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0037] Example 1, a hydraulic transmission mechanism, such as Figure 1 , Figure 2 , Figure 3 , Figure 4 , Figure 5 , Figure 6 , Figure 7 , Figure 8 and Figure 10As shown, the device includes a cylinder body 1, a piston 2 disposed within the cylinder body 1 and capable of reciprocating along the axial direction of the cylinder body 1, and a connecting rod 3 connected to the piston 2 and passing through the cylinder body 1. A first seal 4 and a variable-diameter sealing unit are provided on the circumferential side of the piston 2. The first seal 4 is slidably connected to the inner wall of the cylinder body 1. The variable-diameter sealing unit includes a second seal 5. An annular cavity 501 is formed within the second seal 5, which, when filled with a compressed medium, can be driven to expand radially outward and increase the contact force with the inner wall of the cylinder body 1. The cylinder body 1 is provided with an elastic switching assembly for switching the sealing force of the second seal 5 according to the stroke position and direction of the connecting rod 3. The piston 2 is provided with... A compression assembly is provided, comprising an airbag 6 communicating with the annular cavity 501 and containing a compression medium, a compression plate 14 for squeezing or releasing the airbag, and a gear transmission component pulsatingly connected to the compression plate 14. The gear transmission component is adapted to an elastic switching assembly. When the connecting rod 3 is in the extended stage, the compression plate 14 keeps squeezing the airbag 6. When the connecting rod 3 is in the retracted stage, the elastic switching assembly drives the gear transmission component to rotate in the opposite direction, and the compression plate 14 releases the airbag 6. When the connecting rod 3 is retracted to the minimum extended amount, the elastic switching assembly resets, and the elastic switching assembly drives the gear transmission component to rotate in the forward direction, pre-driving the compression plate 14 to squeeze the airbag 6. The hydraulic transmission mechanism of this application is provided with a gear transmission component and an elastic switching component, and a first seal 4 and a second seal 5 are provided on the circumferential side of the piston 2. When the connecting rod 3 is retracted to the minimum extension, the elastic switching component resets, drives the gear transmission component to rotate in the forward direction, and drives the extrusion plate 14 to extrude the air bladder 6 in advance, so as to pre-expand the second seal 5 radially outward and increase the contact force between it and the inner wall of the cylinder 1, thus pre-establishing a seal. When the connecting rod 3 is in the retraction stage, the elastic switching component drives the gear transmission component to rotate in the reverse direction, and the extrusion plate 14 releases the air bladder 6, so as to achieve the radial contraction of the second seal 5 and reduce the friction between it and the inner wall of the cylinder 1. This solves the technical problem that the existing expansion seal or pressure adaptive seal structure cannot achieve pre-establishment of a seal before the pressure rises and timely reduction of friction at the beginning of the return stroke.

[0038] Example 2, based on Example 1, provides a hydraulic transmission mechanism, as shown in the figure, in which at least two elastic switching components and at least two gear transmission components are arranged circumferentially along the connecting rod 3, with each elastic switching component and gear transmission component corresponding to the other. The arrangement of at least two elastic switching components and at least two gear transmission components circumferentially along the connecting rod 3 ensures stable compression or release of the air bladder 6 on the piston 2, thereby ensuring the stability of the entire mechanism.

[0039] Example 3, based on Example 2, provides a hydraulic transmission mechanism, as shown in the figure. The gear transmission component includes a support platform 9, a threaded sleeve 10, a gear 11, a lead screw 12, and a guide shaft 13. The support platform 9 is fixedly mounted on the piston 2, and the threaded sleeve 10 is rotatably mounted on the support platform 9. The gear 11 is coaxially and fixedly connected to the threaded sleeve 10, and the lead screw 12 is threadedly connected to the threaded sleeve 10. One end of the lead screw 12 is connected to the extrusion plate 14, and the other end is provided with a guide shaft 13 that passes through the support platform 9 and provides sliding guidance. The guide shaft 13 restricts the lead screw 12 to rotate synchronously with the threaded sleeve 10. When the threaded sleeve 10 rotates, the lead screw 12 can drive the extrusion plate 14 to move axially closer to or away from the airbag 6. The fan-shaped rack plate 8 drives the gear 11 and the threaded sleeve 10 to rotate, causing the extrusion plate 14 to move away from or closer to the airbag 6, thereby releasing or compressing and increasing the pressure in the annular cavity 501.

[0040] Example 4, based on Example 3, provides a hydraulic transmission mechanism, as shown in the figure. The elastic switching assembly includes a follower sleeve 7, a sector-shaped rack plate 8, a cylindrical spring 15, and a switching groove. The follower sleeve 7 is rotatably mounted on the connecting rod 3. The sector-shaped rack plate 8 is connected to the follower sleeve 7 and meshes with a gear 11. One end of the cylindrical spring 15 is connected to the follower sleeve 7, and the other end is connected to the piston 2. The switching groove is located on the outer circumference of the follower sleeve 7. The cylinder 1 contains a convex shaft 101 that matches the switching groove and controls whether the follower sleeve 7 can rotate. One end of the cylindrical spring 15 is connected to the follower sleeve 7, and the other end is connected to the piston 2, used to apply a restoring torsional tendency to the follower sleeve 7. The switching groove and the convex shaft 101 are provided to control whether the follower sleeve 7 can rotate.

[0041] Example 5, based on Example 4, provides a hydraulic transmission mechanism, such as... Figure 3 , Figure 4 , Figure 8 and Figure 9As shown, the switching groove includes a first straight groove 702, an arc-shaped groove 703, a second straight groove 704, a spiral groove 705, and an extension 706. The first straight groove 702 and the second straight groove 704 extend along the axial direction of the follower sleeve 7. One end of the first straight groove 702 and the second straight groove 704 are connected by the arc-shaped groove 703, and the other end is connected by the spiral groove 705. The extension 706 is formed at the end of the first straight groove 702 near the spiral groove 705. When the connecting rod 3 extends, the cam 101 moves along the first straight groove 702, and the follower sleeve 7 does not move. When the connecting rod 3 is retracted, the second seal 5 remains in an expanded and sealed state. When the connecting rod 3 is retracted, the cam shaft 101 enters the spiral groove 705. The cooperation between the cam shaft 101 and the spiral groove 705 forces the follower sleeve 7 to rotate. The fan-shaped rack plate 8 drives the gear 11 and the threaded sleeve 10 to rotate in the opposite direction, causing the extrusion plate 14 to release the airbag 6. When the connecting rod 3 is retracted to the minimum extension, the cam shaft 101 moves to the return end through the second straight groove 704. The column spring 15 releases its stored energy and drives the follower sleeve 7 to rotate. The fan-shaped rack plate 8 drives the gear 11 in the forward direction, causing the extrusion plate 14 to re-extrude the airbag 6.

[0042] Example 6, based on Example 5, provides a hydraulic transmission mechanism, such as... Figure 7 and Figure 9 As shown, a one-way guide plate 16 is provided at the position where the spiral groove 705 connects to the first straight groove 702. The one-way guide plate 16 is mounted on the follower sleeve 7 via a rotating shaft, on which a torsion spring is provided. When the connecting rod 3 extends, the convex shaft 101 moves along the first straight groove 702, the follower sleeve 7 does not rotate, and the second seal 5 remains in an expanded sealing state. When the convex shaft 101 reaches the extension 706, the one-way guide plate 16 is pushed open. When the connecting rod 3 retracts, the one-way guide plate 16 guides the convex shaft 101 into the spiral groove 705. The spiral groove 705 and the convex shaft 101 cooperate to replace the linear motion of the connecting rod 3 with the rotational motion of the follower sleeve 7. This ensures that when the connecting rod 3 retracts, the cooperation between the convex shaft 101 and the spiral groove 705 forces the follower sleeve 7 to rotate, and the fan-shaped rack plate 8 drives the gear 11 and the threaded sleeve 10 to rotate in the opposite direction, causing the compression plate 14 to release the airbag 6.

[0043] Example 7, based on Example 6, provides a hydraulic transmission mechanism, such as... Figure 5 and Figure 10 As shown, the follower sleeve 7 has an annular connecting portion 701 inside, and the connecting rod 3 has an annular connecting groove 301. The annular connecting portion 701 is rotatably connected to the annular connecting groove 301. That is, the follower sleeve 7 is sleeved on the connecting rod 3, and the annular connecting portion 701 inside the follower sleeve 7 rotatably engages with the annular connecting groove 301 on the connecting rod 3, so that the follower sleeve 7 can move axially with the connecting rod 3, and at the same time can rotate circumferentially relative to the connecting rod 3.

[0044] Example 8, based on Example 7, provides a hydraulic transmission mechanism, such as... Figure 4 and Figure 10 As shown, the pitch radius of the gear 11 is smaller than that of the sector rack plate 8. This is because when the sector rack plate 8 rotates through a small angle with the follower sleeve 7, the gear 11 and the threaded sleeve 10 can achieve a larger rotational output, thereby increasing the axial displacement of the extrusion plate 14. The threaded transmission pair also has a certain force-saving and self-locking effect, which can reduce the load of the switching action and decrease the possibility of the extrusion plate 14 retracting due to back pressure in the annular cavity 501.

[0045] Example 9, based on Example 8, provides a hydraulic transmission mechanism, such as... Figure 8 As shown, a second annular groove 202 is provided on the circumferential side of the piston 2, and the second seal 5 is sleeved in the second annular groove 202. The annular cavity 501 is continuously arranged or segmented and connected along the circumference of the second seal 5. The annular cavity 501 is formed inside the second seal 5. The annular cavity 501 can be continuously arranged along the circumference of the second seal 5, or it can be composed of multiple interconnected cavity segments. When the annular cavity 501 is filled with compressed medium, the second seal 5 exhibits a radial outward expansion tendency, and the contact force between its outer circumferential surface and the inner wall of the cylinder 1 increases, thereby improving the sealing reliability under high pressure loading conditions.

[0046] Example 10, based on Example 9, provides a hydraulic transmission mechanism, such as... Figure 5 and Figure 6 As shown, a bent portion 502 is formed on the sidewall of the annular cavity 501 to elastically expand when the annular cavity 501 is pressurized, thereby reducing the amount of medium required to drive the second seal 5 to expand radially outward. The bent portion 502 is equivalent to an expandable elastic deformation zone. When the annular cavity 501 is pressurized, the bent portion 502 deforms preferentially and pushes the second seal 5 to expand radially outward, so that the second seal 5 obtains a significant change in sealing force under a small change in the amount of medium.

[0047] Example 11, based on Example 10, a hydraulic transmission mechanism, such as... Figure 8As shown, first annular grooves 201 are respectively provided on both sides of the second annular groove 202, and the first seal 4 is disposed in the first annular groove 201. The piston 2 is located on both sides of the second annular groove 202, and the first annular groove 201 is respectively provided, with the first seal 4 disposed in the first annular groove 201. The first seal 4 slides against the inner wall of the cylinder 1, and is used to provide a basic seal when the second seal 5 is in a natural state or a low contact force state, to prevent air from mixing into the hydraulic system or hydraulic oil from leaking significantly. The two first seals 4 provide a basic seal, while the second seal 5 is used to provide an enhanced seal during the high-load drilling stage. The two first seals 4 and the second seal 5 together form a graded sealing structure.

[0048] Example 12, based on Example 11, provides a hydraulic transmission mechanism, such as... Figure 5 and Figure 6 As shown, the piston 2 is provided with a guiding channel 203, one end of which is connected to the annular cavity 501 and the other end is connected to the airbag 6. The airbag 6 is mounted on the piston 2. When the airbag 6 is squeezed by the compression plate 14, the medium inside it enters the annular cavity 501 through the guiding channel 203. When the compression plate 14 moves away from the airbag 6, the medium in the annular cavity 501 flows back to the airbag 6, causing the second sealing element 5 to reset or reduce the adhesion force.

[0049] Example 13, based on any one of Examples 1 to 12, a hydraulic transmission mechanism, such as Figure 5 and Figure 6 As shown, the compression medium is an inert gas medium or a low-compressibility elastic medium. Using an inert gas medium or a low-compressibility elastic medium is to reduce the impact of temperature rise and repeated compression on the stability of the sealing state. The compression medium can also be nitrogen.

[0050] When embodiment 12 is implemented, when the connecting rod 3 extends, the cam shaft 101 moves along the first straight groove 702, the follower sleeve 7 does not rotate, and the second seal 5 remains in an expanded sealing state; when the cam shaft 101 reaches the extension 706, the guide plate 16 is pushed open, allowing the cam shaft 101 to enter the extension 706.

[0051] When the connecting rod 3 is retracted in the reverse direction, the guide plate 16 guides the cam shaft 101 into the spiral groove 705. The engagement of the cam shaft 101 and the spiral groove 705 forces the follower sleeve 7 to rotate. The fan-shaped rack plate 8 drives the gear 11 and the threaded sleeve 10 to rotate, causing the extrusion plate 14 to move away from the airbag 6, thereby releasing the pressure in the annular cavity 501.

[0052] When the connecting rod 3 retracts to its minimum extension, the cam shaft 101 moves to the return end via the second straight groove 704. The cylindrical spring 15 releases its stored energy and drives the follower sleeve 7 to rotate actively. The fan-shaped rack plate 8 drives the gear 11 in the opposite direction, causing the compression plate 14 to recompress the airbag 6. As a result, the second seal 5 has already returned to its expanded state before the next extension and loading of the connecting rod 3, realizing the early establishment of sealing force, instead of passively deforming after the hydraulic oil pressure rises.

[0053] Example 14, based on any one of Examples 1 to 13, a geological drilling apparatus, such as Figure 1 , Figure 2 , Figure 3 , Figure 4 , Figure 5 , Figure 6 , Figure 7 , Figure 8 and Figure 10 As shown, the system includes a frame, main rod, power mechanism, detection drill bit, wireline coring assembly, ground-penetrating radar (GPR) detection assembly, and the aforementioned hydraulic transmission mechanism. The hydraulic transmission mechanism drives or adjusts the feed stroke of the main rod. The power mechanism drives the detection drill bit to rotate. The GPR detection assembly is positioned on the detection drill bit, main rod, or near the drilling front end to detect surrounding rock ahead of the face of the borehole or geological anomalies around the borehole during drilling. The wireline coring assembly is used to retrieve core samples after drilling to a predetermined depth. In the geological drilling apparatus, the hydraulic transmission mechanism can be installed between the frame and the main rod, or on the hydraulic actuator used to drive the detection drill bit feed. The power mechanism drives the detection drill bit to rotate and / or advance, and the wireline coring assembly retrieves core samples after drilling to a predetermined depth. The GPR detection assembly can be positioned on the detection drill bit, the front end of the main rod, or near the borehole front end to acquire radar echo data of the surrounding rock interface and anomalies during drilling.

[0054] Example 15, based on Example 14, a geological drilling device, such as... Figure 1 , Figure 2 , Figure 3 , Figure 4 , Figure 5 , Figure 6 , Figure 7 , Figure 8 and Figure 10 As shown, the ground-penetrating radar detection component includes a radar antenna, a radar signal transceiver module, an attitude or depth acquisition module, and a data processing module. The data processing module is configured to correlate radar echo data with drilling depth, drilling resistance, or core sampling information to form advanced geological identification results.

[0055] In Example 15, when using the aforementioned geological drilling device for detection, the equipment is first positioned at the tunnel face or the area to be detected, and the drilling direction and radar acquisition parameters are set. Then, the stroke pre-switching, labor-saving hydraulic transmission structure and power mechanism are activated to rotate the detection drill bit. Before the connecting rod extends and enters the loading stage, the second seal 5 is already in an expanded sealing state, which reduces initial loading leakage and improves stroke response accuracy. After drilling to the predetermined depth, the connecting rod is retracted, and the second seal 5 promptly reduces the contact force, minimizing recovery resistance and seal wear. The drilling and recovery actions are repeated until the designed detection depth is reached. Samples are then retrieved using the wireline coring assembly, and geological identification is performed by combining radar echoes and sample core data.

[0056] Example 16, based on Example 14 or 15, a method of use, such as Figure 1 , Figure 2 , Figure 3 , Figure 4 , Figure 5 , Figure 6 , Figure 7 , Figure 8 and Figure 10 As shown, it includes the following steps: S1. Arrange the drilling mechanism at the tunnel face or the location to be detected, and set the drilling direction, single feed depth and radar acquisition parameters. S2. Control the hydraulic transmission mechanism and the power mechanism to make the probe drill bit rotate in a set direction; before the connecting rod 3 extends and bears the drilling load, the elastic switching component and the gear transmission component jointly drive the extrusion plate 14 to pre-compress the air bag 6, thereby making the second sealing member 5 in an expanded sealing state. S3. During the drilling process, the geological radar detection component is activated synchronously or in stages to collect radar echo data in front of the tunnel face or around the borehole, and to record the corresponding drilling depth and drilling conditions. S4. When the probe drill bit is rotated to a predetermined depth, the connecting rod 3 is controlled to retract. The cooperation of the convex shaft 101 and the spiral groove 705 drives the follower sleeve 7 to rotate, so that the extrusion plate 14 releases the airbag 6 and reduces the adhesion force between the second seal 5 and the inner wall of the cylinder 1. S5. Repeat steps S2 to S4 until the predetermined detection depth is reached, and use the rope core sampling assembly to retrieve the sample. S6. Comprehensively compare the radar echo data, drilling parameters, and core information of samples taken from the wireline coring assembly to determine the location and extent of faults, fracture zones, water-rich areas, karst caves, or weak interlayers.

[0057] Example 17, based on Example 16, a method of use, such as... Figure 1 , Figure 2, Figure 3 , Figure 4 , Figure 5 , Figure 6 , Figure 7 , Figure 8 and Figure 10 As shown, in step S3, when the radar echo shows an abnormal reflection interface or the drilling resistance changes abruptly, the single feed depth is reduced and the radar sampling density is increased.

[0058] In Example 17, S1, the drilling mechanism is placed at the tunnel face or the location to be detected, and the drilling direction, single feed depth and radar acquisition parameters are set. S2. Control the hydraulic transmission mechanism and the power mechanism to make the probe drill bit rotate in a set direction; before the connecting rod 3 extends and bears the drilling load, the elastic switching component and the gear transmission component jointly drive the extrusion plate 14 to pre-compress the air bag 6, thereby making the second sealing member 5 in an expanded sealing state. S3. During the drilling process, the geological radar detection component is activated synchronously or in stages to collect radar echo data in front of the tunnel face or around the borehole, and record the corresponding drilling depth and drilling conditions. When the radar echo shows an abnormal reflection interface or the drilling resistance changes abruptly, the single feed depth is reduced and the radar sampling density is increased. S4. When the probe drill bit is rotated to a predetermined depth, the connecting rod 3 is controlled to retract. The cooperation of the convex shaft 101 and the spiral groove 705 drives the follower sleeve 7 to rotate, so that the extrusion plate 14 releases the airbag 6 and reduces the adhesion force between the second seal 5 and the inner wall of the cylinder 1. S5. Repeat steps S2 to S4 until the predetermined detection depth is reached, and use the rope core sampling assembly to retrieve the sample. S6. Comprehensively compare the radar echo data, drilling parameters, and core information of samples taken from the wireline coring assembly to determine the location and extent of faults, fracture zones, water-rich areas, karst caves, or weak interlayers.

[0059] The above embodiments merely illustrate several implementation methods of the present invention, and their descriptions are relatively specific and detailed, but they should not be construed as limiting the scope of the present invention. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these all fall within the protection scope of the present invention. Therefore, the protection scope of this patent should be determined by the appended claims.

Claims

1. A hydraulic transmission mechanism, comprising a cylinder (1), a piston (2) disposed within the cylinder (1) and capable of reciprocating along the axial direction of the cylinder (1), and a connecting rod (3) connected to the piston (2) and passing through the cylinder (1), characterized in that, The piston (2) is provided with a first seal (4) and a variable diameter sealing unit on its circumferential side. The first seal (4) is slidably connected to the inner wall of the cylinder (1). The variable diameter sealing unit includes a second seal (5). An annular cavity (501) is formed inside the second seal (5) that can drive the second seal (5) to expand radially outward and increase the contact force with the inner wall of the cylinder (1) when a compressed medium is filled in. The cylinder (1) is provided with an elastic switching component for switching the sealing force of the second seal (5) according to the stroke position and stroke direction of the connecting rod (3). A compression component is provided on the piston (2). The compression component includes components that communicate with the annular cavity (501) and An airbag (6) containing a compression medium, a compression plate (14) for squeezing or releasing the airbag, and a gear transmission component connected to the compression plate (14) are adapted to the elastic switching component. When the connecting rod (3) is in the extended stage, the compression plate (14) keeps squeezing the airbag (6). When the connecting rod (3) is in the retracted stage, the elastic switching component drives the gear transmission component to rotate in the opposite direction, and the compression plate (14) releases the airbag (6). When the connecting rod (3) is retracted to the minimum extension amount, the elastic switching component resets, and the elastic switching component drives the gear transmission component to rotate in the forward direction, pre-driving the compression plate (14) to squeeze the airbag (6).

2. The hydraulic transmission mechanism according to claim 1, characterized in that, At least two elastic switching components and at least two gear transmission components are arranged along the circumference of the connecting rod (3), with the elastic switching components and gear transmission components corresponding one to one.

3. The hydraulic transmission mechanism according to claim 2, characterized in that, The gear transmission component includes a support platform (9), a threaded sleeve (10), a gear (11), a lead screw (12), and a guide shaft (13). The support platform (9) is fixedly mounted on the piston (2), the threaded sleeve (10) is rotatably mounted on the support platform (9), the gear (11) is coaxially fixedly connected to the threaded sleeve (10), the lead screw (12) is threadedly connected to the threaded sleeve (10), one end of the lead screw (12) is connected to the extrusion plate (14), and the other end is provided with a guide shaft (13) that passes through the support platform (9) and slides and guides.

4. The hydraulic transmission mechanism according to claim 3, characterized in that, The elastic switching assembly includes a follower sleeve (7), a fan-shaped rack plate (8), a cylindrical spring (15), and a switching groove. The follower sleeve (7) is rotatably mounted on the connecting rod (3). The fan-shaped rack plate (8) is connected to the follower sleeve (7) and meshes with the gear (11). One end of the cylindrical spring (15) is connected to the follower sleeve (7), and the other end is connected to the piston (2). The switching groove is set on the outer circumference of the follower sleeve 7. The cylinder (1) is provided with a convex shaft (101) that is adapted to the switching groove and controls whether the follower sleeve (7) can rotate.

5. The hydraulic transmission mechanism according to claim 4, characterized in that, The switching groove includes a first straight groove (702), an arc groove (703), a second straight groove (704), a spiral groove (705), and an extension (706). The first straight groove (702) and the second straight groove (704) extend along the axial direction of the follower sleeve (7). One end of the first straight groove (702) and the second straight groove (704) are connected by the arc groove (703), and the other end is connected by the spiral groove (705). The extension (706) is formed at the end of the first straight groove (702) near the spiral groove (705). When the connecting rod (3) extends, the cam (101) moves along the first straight groove (702), and the follower sleeve (7) does not rotate. When the connecting rod 3 is retracted, the second seal (5) remains in an expanded sealing state; when the connecting rod 3 is retracted, the cam shaft (101) enters the spiral groove (705), and the cooperation between the cam shaft (101) and the spiral groove (705) forces the follower sleeve (7) to rotate. The fan-shaped rack plate (8) drives the gear (11) and the threaded sleeve (10) to rotate in the opposite direction, so that the extrusion plate (14) releases the airbag (6); when the connecting rod (3) is retracted to the minimum extension, the cam shaft (101) moves to the return end through the second straight groove (704), the column spring (15) releases the stored energy and drives the follower sleeve (7) to rotate. The fan-shaped rack plate (8) drives the gear (11) in the forward direction, so that the extrusion plate (14) re-extrudes the airbag (6).

6. The hydraulic transmission mechanism according to claim 5, characterized in that, A one-way guide plate (16) is provided at the position where the spiral groove (705) connects with the first straight groove (702). The one-way guide plate (16) is mounted on the follower sleeve (7) via a rotating shaft. A torsion spring is provided on the rotating shaft. When the connecting rod (3) extends, the convex shaft (101) moves along the first straight groove (702), and the follower sleeve (7) does not rotate. The second seal (5) remains in an expanded sealing state. When the convex shaft (101) reaches the extension (706), the one-way guide plate (16) is pushed open. When the connecting rod 3 is retracted, the one-way guide plate (16) guides the convex shaft (101) into the spiral groove (705).

7. The hydraulic transmission mechanism according to claim 6, characterized in that, The follower sleeve (7) has an annular connecting part (701) inside, and the connecting rod (3) is provided with an annular connecting groove (301). The annular connecting part (701) is rotatably connected to the annular connecting groove (301).

8. The hydraulic transmission mechanism according to claim 7, characterized in that, The pitch radius of the gear (11) is smaller than that of the sector rack (8).

9. The hydraulic transmission mechanism according to claim 8, characterized in that, The piston (2) has a second annular groove (202) on its circumferential side, and the second seal (5) is fitted inside the second annular groove (202). The annular cavity (501) is continuously arranged or segmentedly connected along the circumference of the second seal (5).

10. The hydraulic transmission mechanism according to claim 9, characterized in that, The annular cavity (501) has a bend (502) formed on its sidewall for elastic expansion when the annular cavity (501) is pressurized, so as to reduce the amount of medium required to drive the second seal (5) to expand radially outward.

11. The hydraulic transmission mechanism according to claim 10, characterized in that, The second annular groove (202) has a first annular groove (201) on each side, and the first sealing member (4) is disposed in the first annular groove (201).

12. The hydraulic transmission mechanism according to claim 11, characterized in that, The piston (2) is provided with a connecting channel (203), one end of which is connected to the annular cavity (501) and the other end is connected to the airbag (6).

13. The hydraulic transmission mechanism according to any one of claims 1 to 12, characterized in that, The compression medium is an inert gas medium or a low-compressibility elastic medium.

14. A geological drilling device, characterized in that, The system includes a frame, a main rod, a power mechanism, a detection drill bit, a wireline coring assembly, a ground-penetrating radar (GPR) detection assembly, and a hydraulic transmission mechanism as described in any one of claims 1 to 13. The hydraulic transmission mechanism is used to drive or adjust the feed stroke of the main rod, the power mechanism is used to drive the detection drill bit to rotate, the GPR detection assembly is located at the detection drill bit, the main rod, or near the drilling front end to detect the surrounding rock in front of the face of the hole or geological anomalies around the borehole during drilling, and the wireline coring assembly is used to retrieve core samples after drilling to a predetermined depth.

15. The geological drilling apparatus according to claim 14, characterized in that, The ground-penetrating radar detection component includes a radar antenna, a radar signal transceiver module, an attitude or depth acquisition module, and a data processing module. The data processing module is configured to correlate radar echo data with drilling depth, drilling resistance, or core sampling information to form advanced geological identification results.

16. A method of using the geological drilling apparatus of claim 14 or 15, characterized in that, Includes the following steps: S1. Arrange the drilling mechanism at the tunnel face or the location to be detected, and set the drilling direction, single feed depth and radar acquisition parameters. S2. Control the hydraulic transmission mechanism and the power mechanism to make the probe drill bit rotate in the set direction; before the connecting rod (3) extends and bears the drilling load, the elastic switching component and the gear transmission component jointly drive the extrusion plate (14) to pre-compress the air bag (6), thereby making the second seal (5) in an expanded sealing state; S3. During the drilling process, the geological radar detection component is activated synchronously or in stages to collect radar echo data in front of the tunnel face or around the borehole, and to record the corresponding drilling depth and drilling conditions. S4. When the probe drill bit is rotated to a predetermined depth, the connecting rod (3) is controlled to retract. The cooperation of the convex shaft (101) and the spiral groove (705) drives the follower sleeve (7) to rotate, so that the extrusion plate (14) releases the airbag (6) and reduces the adhesion force between the second seal (5) and the inner wall of the cylinder (1). S5. Repeat steps S2 to S4 until the predetermined detection depth is reached, and use the rope core sampling assembly to retrieve the sample. S6. Comprehensively compare the radar echo data, drilling parameters, and core information of samples taken from the wireline coring assembly to determine the location and extent of faults, fracture zones, water-rich areas, karst caves, or weak interlayers.

17. The method of use according to claim 16, characterized in that, In step S3, when an abnormal reflection interface appears in the radar echo or a sudden change occurs in the drilling resistance, the single feed depth is reduced and the radar sampling density is increased.

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