A downhole geophysical sensor

Abstract

This invention discloses a downhole geophone for geophysical exploration, relating to the field of downhole geophone technology. It includes an upper geophone cylinder and a lower geophone cylinder connected together, and further includes: a driving component for driving the upper and lower geophone cylinders to move closer or further apart; and an upper arm and a lower arm respectively rotatably connected to the upper and lower geophone cylinders. This invention uses an interlaced rack and pinion drive gear to unfold the arms into a three-dimensional X-shaped support, achieving rigid multi-point contact without signal attenuation. The "claw-shaped" lower arm is equipped with a tie rod to enhance stability, or a single long rack is used to optimize transmission. The symmetrical X-shaped support improves contact uniformity. Both methods avoid shear wave distortion and effectively improve the stability of the geophone when fixed in the well. Compared to traditional airbags, both rigid support systems achieve efficient seismic wave transmission, especially avoiding waveform distortion of shear waves caused by insufficient medium stiffness, providing more accurate raw signals for geological stratum determination.

Description

Technical Field

[0001] This invention belongs to the field of downhole detector technology, specifically, it relates to a downhole detector for geophysical exploration. Background Technology

[0002] In the field of geophysical exploration, accurate acquisition of downhole seismic wave signals is a core component for geological stratigraphic analysis and target material detection, widely applied in oil and gas exploration, solid mineral (such as coal and metal ores) resource exploration, and geological structure research. In this process, the geophone, as a key sensing device, needs to penetrate deep into the well and capture seismic wave signals at different depths. The typical workflow is as follows: the geophone is lowered to a predetermined depth in the well using a hoisting rope under gravity; the attached anchoring device is then activated to stably fix the geophone to the well wall; subsequently, a surface seismic source is excited, and the geophone acquires the downhole seismic wave signal; after acquiring the signal for a single layer, the anchoring device is released, and the geophone is lowered to a new depth to repeat the acquisition process. Throughout this process, the well wall stability achieved by the geophone via the anchoring device directly determines the accuracy of the seismic wave signal acquisition and is a crucial prerequisite for ensuring the reliability of subsequent geological analysis results.

[0003] Currently, among the mounting and fixing schemes for geophones in wells, the airbag push-fit mode has become one of the most widely used technical routes due to its relatively simple structure and high flexibility in adapting to different well diameters. Its working principle is as follows: compressed air is injected into an airbag placed around the geophone, causing the airbag to expand and fit tightly against the well wall. The friction between the airbag and the well wall secures the geophone. However, this mode has significant technical limitations in practical applications: because the airbag body is a hollow elastic structure and requires gas expansion for push-fitting, it inherently possesses both gas compressibility and the elastic deformation characteristics of the airbag material. When a ground seismic source is activated, as seismic waves propagate downhole and pass through the well wall, airbag, and geophone, the compressibility and elastic deformation of the airbag will significantly absorb and attenuate the seismic waves, especially affecting seismic wave components such as shear waves that are sensitive to the stiffness of the propagation medium. This signal attenuation can cause problems such as amplitude reduction and waveform distortion in the seismic wave signal ultimately received by the detector, directly causing signal acquisition errors and affecting the accuracy of subsequent geological stratum determination and target material detection. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to overcome the shortcomings of the prior art and provide a downhole geophone for geophysical exploration that can overcome or at least partially solve the above problems.

[0005] To solve the above-mentioned technical problems, the basic concept of the technical solution adopted by the present invention is as follows: a downhole geophone for geophysical exploration, including an upper geophone cylinder and a lower geophone cylinder connected together, and further including: a driving component for driving the upper geophone cylinder and the lower geophone cylinder to move closer or further apart; an upper arm and a lower arm respectively rotatably connected to the upper geophone cylinder and the lower geophone cylinder, the upper arm and the lower arm forming a " / " shape when extended, and forming a three-dimensional X-shaped support in the circumferential direction; mounting slots respectively formed on the upper geophone cylinder and the lower geophone cylinder, the upper arm and the lower arm respectively connected to the corresponding mounting slots; a plurality of telescopic rods respectively set on the upper geophone cylinder and the lower geophone cylinder, the telescopic rods being equipped with protective plates; when the upper arm and the lower arm are extended, the protective plates are extended accordingly.

[0006] Preferably, the driving component includes a cylinder, which is installed between the upper and lower cylinders of the detector; multiple racks 1 and 2 are circumferentially fixedly connected to the upper and lower cylinders of the detector, respectively, and the racks 1 and 2 are staggered; a gear is rotatably connected in the mounting groove, and one end of the upper arm and lower arm is fixedly connected to the corresponding gear, and one end of rack 1 and rack 2 respectively passes through the mounting groove and meshes with the corresponding gear.

[0007] Preferably, the plurality of telescopic rods are rotatably connected between the upper arm and the lower cylinder of the detector, and between the lower arm and the upper cylinder of the detector, forming a triangular structure area.

[0008] Preferably, the mounting groove includes a mounting cavity, a storage groove communicating with the mounting cavity, and a sliding groove formed in the storage groove and communicating with the mounting cavity. The upper arm and lower arm are located in the storage groove after being retracted. The upper cylinder and lower cylinder of the detector are both provided with guide holes, which are communicating with the mounting cavity. The rack one and rack two slide in the sliding groove through the guide holes.

[0009] Preferably, the driving component includes a cylinder, which is installed between the upper and lower cylinders of the detector; a long rack is connected between the upper and lower cylinders of the detector, and limit blocks are fixedly connected to both ends of the long rack; a gear is rotatably connected in the mounting groove, and one end of the upper arm and lower arm is fixedly connected to the corresponding gear; both ends of the long rack pass through guide holes opened on the upper and lower cylinders of the detector and enter the mounting groove, respectively, and mesh with the corresponding gear; the mounting groove includes a mounting cavity, a receiving groove communicating with the mounting cavity, and a sliding groove opened in the receiving groove, and a limit flange is formed between the sliding groove and the mounting cavity.

[0010] Preferably, the two ends of the plurality of telescopic rods are rotatably connected between the upper arm and the lower arm, respectively, and when the upper arm and the lower arm are extended, the protective plate is in contact with the well wall.

[0011] Preferably, a triangular structural region 2 is formed between the upper arm, the lower arm, and the telescopic arm.

[0012] Preferably, a tie rod is fixedly connected to the outer surface of the protective plate.

[0013] Furthermore, multiple elastic ropes are connected between the upper arm and the upper end of the detector's upper cylinder. A protective net is fixedly connected between adjacent elastic ropes, and an elastic rope is fixedly connected to the upper edge of the protective net. When the upper arm is extended, it pulls the protective net to unfold. When the upper arm is retracted, the protective net is wrapped around the outer periphery of the detector's upper cylinder by the elastic rope.

[0014] Furthermore, a limiting cavity is provided at the upper end of the detector upper cylinder, and a sliding sleeve is slidably connected in the limiting cavity. A spring is provided between the end of the sliding sleeve and the bottom wall of the limiting cavity, and one end of the elastic rope away from the upper arm is connected to the sliding sleeve.

[0015] By adopting the above technical solution, the present invention has the following beneficial effects compared with the prior art: 1. In the first embodiment of this downhole geophone for geophysical exploration, the upper and lower booms are extended by the staggered racks 1 and 2 driving gears to form a three-dimensional X-shaped support. This changes the contact between the geophone and the wellbore from a surface contact of the airbag to a rigid multi-point contact of the boom and protective plate. Seismic waves can be directly transmitted to the geophone through the wellbore via the protective plate, telescopic rod, and boom, without signal attenuation caused by elastic deformation. At the same time, when the lower boom is extended, the angle between it and the outer periphery of the lower cylinder of the geophone is less than 90°, forming a "claw-like" gripping structure. Combined with the piercing rod penetrating the surface of the wellbore, this further strengthens the stability of the rigid connection and avoids signal distortion caused by geophone displacement.

[0016] 2. In the second embodiment of the geophysical exploration downhole geophone, the transmission structure is optimized based on rigid support. A single long rack synchronously drives the gears in the upper and lower cylinders of the geophone, so that the upper and lower arms form a symmetrical three-dimensional X-shaped support. With the help of the limiting flange, the arms are fully extended, and the protective plate is vertically attached to the well wall and the tie rod is driven into the well wall, further improving the uniformity and firmness of the rigid contact. Compared with the traditional airbag, the rigid support system of both structural methods can achieve efficient transmission of seismic waves, especially avoiding the waveform distortion of shear waves caused by insufficient medium stiffness, providing more accurate original signals for geological stratum determination.

[0017] 3. Traditional airbag-type downhole geophones for geophysical exploration lack targeted protective structures, making them susceptible to damage from debris falling from the wellbore, causing additional vibrations and unsuitable for complex well conditions. This invention addresses this issue through a layered protection design, with different embodiments featuring complementary protective structures. In the first embodiment, the protective plates exhibit differentiated shapes as the boom extends: the upper boom's protective plate forms an inverted V-shape with the wellbore, guiding debris from above downhole to prevent direct impact on the geophone and interference vibrations; the lower boom's protective plate forms a V-shaped collection area with the wellbore, its narrower bottom and wider top structure quickly filling with debris, allowing the upper part of the protective plate to contact the wellbore through debris, increasing the conduction area and further improving seismic wave transmission efficiency; and when the boom retracts, debris in the V-shaped collection area automatically falls off without additional cleaning, while the protective plate surrounds the geophone's perimeter, forming a protective barrier during the lowering process.

[0018] 4. In the second embodiment of the protective structure of this geophysical exploration downhole geophone, elastic rope one, elastic rope two, and a protective net are added to the protective plate. When the upper boom extends, elastic rope one is pulled, causing the protective net to open and shield the top of the geophone. At the same time, the sliding sleeve compresses the spring, using the elastic deformation of the spring to buffer the impact force of falling debris and reduce additional vibration. When the upper boom retracts, elastic rope two contracts, causing the protective net to fit tightly against the upper cylinder of the geophone, avoiding interference with the lifting and lowering action. The spring also pushes the sliding sleeve upward, increasing the slope of the protective net to achieve automatic debris removal and prevent debris from jamming the boom structure. More importantly, the pulling action of elastic rope one causes the lower boom to extend first, and the anchor rods are driven into the well wall one by one, avoiding the huge resistance generated by simultaneous driving and ensuring a firm contact between the boom and the well wall, further improving the fixation stability.

[0019] 5. In the first embodiment of the geophysical exploration downhole detector, staggered racks one and two are used in conjunction with clearance grooves on the upper and lower booms to prevent the upper and lower booms from colliding with racks one and two during rotation, ensuring that multiple booms deploy synchronously and improving uniform support requirements. In the second embodiment, multiple racks are simplified into a single long rack, reducing the number of transmission components and lowering the probability of failure. Furthermore, the limiting block and the limiting protrusion cooperate to limit the rack displacement stroke, ensuring that the boom is fully deployed and avoiding the impact of insufficient transmission on the fixing effect.

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

[0021] In the attached diagram: Figure 1 This is a schematic diagram of the structure of a downhole detector for geophysical exploration proposed in this invention. Figure 1 ; Figure 2 This is a schematic diagram of the structure of a downhole detector for geophysical exploration proposed in this invention. Figure 2 ; Figure 3 This is a three-dimensional structural diagram of a downhole geophone for geophysical exploration proposed in this invention; Figure 4 This is a top view of a downhole geophone for geophysical exploration proposed in this invention; Figure 5 This is a schematic diagram of rack one and rack two of a downhole geophone for geophysical exploration proposed in this invention; Figure 6 This is a schematic diagram of the mounting cavity, receiving groove, sliding groove, and guide hole of a downhole geophone for geophysical exploration proposed in this invention. Figure 7 This is a schematic diagram of the protective panel after it has been vertically unfolded. Figure 8 This is a schematic diagram of the second triangular structure of a downhole geophone for geophysical exploration proposed in this invention; Figure 9 This is a schematic diagram of the limiting slide cavity, sliding sleeve, and spring of a downhole geophone for geophysical exploration proposed in this invention. Figure 10 This is a schematic diagram of the upper and lower arms of a downhole geophone for geophysical exploration proposed in this invention after they have been deployed. Figure 11 This is a schematic diagram of the limiting flange of a downhole geophone for geophysical exploration proposed in this invention; Figure 12 This is a schematic diagram of the upper and lower booms after they are retracted. Figure 13 This is a schematic diagram of the structure of an elastic rope for a downhole geophone used in geophysical exploration, as proposed in this invention. Figure 14 This is a schematic diagram of the clearance groove of a downhole geophone for geophysical exploration proposed in this invention.

[0022] In the diagram: 1. Detector upper cylinder; 10. Cylinder; 11. Rack 1; 12. Upper arm; 13. Flexible protective sleeve; 14. Long rack; 141. Limiting block; 2. Detector lower cylinder; 20. Triangular structure area one; 200. Triangular structure area two; 21. Rack two; 22. Lower arm; 3. Mounting slot; 30. Mounting cavity; 31. Storage slot; 32. Slide groove; 33. Limiting flange; 34. Guide hole; 4. Gear; 40. Clearance groove; 5. Telescopic pole; 51. Protective plate; 52. Tie rod; 6. Limiting cavity; 61. Sliding sleeve; 62. Spring; 63. Elastic rope one; 64. Protective net; 65. Elastic rope two; 7. Connecting rod. Detailed Implementation

[0023] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments will be clearly and completely described below with reference to the accompanying drawings. The following embodiments are used to illustrate the present invention, but are not intended to limit the scope of the present invention.

[0024] The following is in conjunction with the appendix Figure 1 - Appendix Figure 14 The technical solutions provided in the various embodiments of the present invention will be described in detail.

[0025] Example 1: Refer to Figures 1-6 A downhole geophone for geophysical exploration includes an upper geophone cylinder 1 and a lower geophone cylinder 2 connected together. A flexible protective sleeve 13 connects the upper geophone cylinder 1 and the lower geophone cylinder 2 to protect the area between them. The cavities in the upper geophone cylinder 1 and the lower geophone cylinder 2 can be used to install the electrical components of the geophone. The device also includes a drive unit for driving the upper geophone cylinder 1 and the lower geophone cylinder 2 to move closer or further apart; and upper arm rods 12 and lower arm rods 22 respectively rotatably connected to the upper geophone cylinder 1 and the lower geophone cylinder 2. When the opposing upper arm rods 12 and lower arm rods 22 are extended, they form a " / " shape, and multiple " / " shapes form a three-dimensional X-shaped support in the circumferential direction (see reference). Figure 3 It's important to understand that the " / " shape refers to a shape that appears in the same direction and angle, as shown in the reference diagram. Figure 1 (Viewpoint: when the upper arm 12 and lower arm 22 are extended, they form a " / " shape as observed from this direction and angle); mounting slots 3 are respectively opened on the upper cylinder 1 and lower cylinder 2 of the detector, and the upper arm 12 and lower arm 22 are respectively connected to the corresponding mounting slots 3; multiple telescopic rods 5 are respectively set on the upper cylinder 1 and lower cylinder 2 of the detector, and protective plates 51 are installed on the telescopic rods 5; when the upper arm 12 and lower arm 22 are extended, the protective plates 51 are extended accordingly.)

[0026] The driving component includes a cylinder 10, which is installed between the upper cylinder 1 and the lower cylinder 2 of the detector. Multiple racks 11 and 21 are circumferentially fixedly connected to the upper cylinder 1 and the lower cylinder 2, respectively. The racks 11 and 21 are staggered, and the upper arm 12 and lower arm 22 are also staggered. A gear 4 is rotatably connected in the mounting groove 3. One end of the upper arm 12 and lower arm 22 is fixedly connected to the corresponding gear 4. One end of each rack 11 and rack 21 passes through the mounting groove 3 and meshes with the corresponding gear 4. A clearance groove 40 is provided on the upper arm 12 and lower arm 22, through which the racks 11 and 21 pass. The clearance groove 40 prevents the upper arm 12 and lower arm 22 from colliding with the racks 11 and 21 during rotation.

[0027] Multiple telescopic rods 5 are respectively connected between the upper arm rod 12 and the lower cylinder 2 of the detector, and between the lower arm rod 22 and the upper cylinder 1 of the detector, forming a triangular structure area 20, which further improves the support of the detector.

[0028] The mounting slot 3 includes a mounting cavity 30, a storage slot 31 connected to the mounting cavity 30, and a sliding groove 32 opened in the storage slot 31 and connected to the mounting cavity 30. The upper arm 12 and the lower arm 22 are located in the storage slot 31 after being retracted. The upper cylinder 1 and the lower cylinder 2 of the detector are both provided with guide holes 34, which are connected to the mounting cavity 30. The rack 11 and the rack 21 slide in the sliding groove 32 through the guide holes 34 respectively.

[0029] A tie rod 52 is fixedly connected to the outer surface of the protective plate 51. The tie rod 52 is located on the protective plate 51 closer to the rotatable connection between the telescopic rod 5 and the upper arm rod 12 or the lower arm rod 22.

[0030] When in use, the device is connected to a rope and then dropped into a pre-drilled well. Before the device is dropped in, the upper arm 12 and the lower arm 22 are both in a retracted position, that is, they are horizontal with the upper cylinder 1 and the lower cylinder 2 of the detector. In this state, the protective plate 51 is also horizontal, and the upper cylinder 1 and the lower cylinder 2 of the detector are close to each other. Once the device is lowered to the designated depth, air is injected into cylinder 10 through the air pipe connected to the device. The telescopic end of cylinder 10 extends, pushing the upper detector cylinder 1 and the lower detector cylinder 2 away from each other. During this process, racks 11 and 21 connected to the upper detector cylinder 1 and the lower detector cylinder 2 respectively mesh, driving the corresponding gears 4 to rotate. When the gears 4 rotate, they drive the upper arm 12 and the lower arm 22 to extend outwards, and the extension direction of the upper arm 12 and the lower arm 22 is towards the space between the upper detector cylinder 1 and the lower detector cylinder 2, thus initially... In its current state, the upper boom 12 and lower boom 22 are vertical (i.e., the included angle between the upper boom 12 and lower boom 22 is approximately 180°). This changes to an angle between the upper boom 12 and lower boom 22 that is much smaller than 180°, and the upper boom 12 and lower boom 22, which are positioned opposite each other, form a " / " shape and together form a three-dimensional X-shaped support structure in the circumferential direction. The three-dimensional X-shaped support structure refers to the three-dimensional cross support form formed by adjacent upper boom 12 and lower boom 22 in the unfolded state. Its main purpose is to form evenly distributed support points on the well wall surface.

[0031] After being deployed, one end of the upper arm 12 and the lower arm 22 are in tight contact with the well wall, thereby fixing the upper cylinder 1 and the lower cylinder 2 of the geophone in the well. Compared with the existing technology that uses airbags to fix the geophone in the well, this device uses the rigid contact of mechanical transmission to replace the elastic contact of the airbag. From the structural design, it eliminates the absorption effect of compressible materials on seismic waves. At the same time, the arm design of the X-shaped support structure enhances the support stability in the circumferential direction. Furthermore, since the angle between the lower boom 22 and the outer periphery of the lower detector cylinder 2 is less than 90° when the lower boom 22 is extended, the lower boom 22 acts like an extended "claw," firmly contacting the well wall. Also, since the distance between the upper detector cylinder 1 and the lower detector cylinder 2 is controlled by the cylinder 10, the lower boom 22 will not rotate under its own weight, provided the cylinder 10 does not leak. Therefore, the extension method of the lower boom 22 can firmly support the upper detector cylinder 1 and the lower detector cylinder 2 in the well. Compared to the existing technology that uses an elastic airbag for fixing, the extended "claw" structure of the lower boom 22, with its rigid multi-point contact, provides better stability for the upper detector cylinder 1 and the lower detector cylinder 2.

[0032] In addition, a three-dimensional X-shaped support structure is formed between the deployed lower arm 22 and the deployed upper arm 12 in the circumferential direction of the detector upper cylinder 1 and the detector lower cylinder 2, which forms a constraint in the circumferential direction and enhances the contact stability between the detector and the well wall.

[0033] When the upper boom 12 and lower boom 22 are extended, the protective plate 51 installed on them will also be extended and close to the well wall. The protective plate 51 designed to be extended can protect the upper cylinder 1 and lower cylinder 2 of the geophone when the ground starts the seismic source, so as to prevent the well wall at the fixed position of the geophone from falling off due to the fixing of the geophone and hitting the geophone, causing the geophone to vibrate significantly and affecting the reception of the geophone vibration wave. The protective plate 51 of the upper boom 12 forms an inverted V-shape with the well wall, which can directly guide the debris falling off the well wall to fall down into the well (it should be understood that the debris refers to the broken soil falling off the well wall), avoiding direct impact on the detector. Through the guidance of the protective plate 51, the additional vibration waves generated by the debris falling off and hitting the detector are reduced.

[0034] The protective plate 51 of the lower boom 22 forms a V-shape with the well wall, which can form a debris collection mode. The debris is collected in the V-shaped collection area between the well wall and the protective plate 51. Since the V-shaped collection area is narrow at the bottom and wide at the top, the narrow area at the bottom can be filled with debris more quickly. This allows the upper part of the protective plate 51 to contact the well wall through the debris, increasing the contact area between the detector and the well wall, further improving the efficiency of the transmission of vibration waves to the detector, and making the detector more accurate in detecting vibration waves.

[0035] After a single test is completed, the telescopic end of cylinder 10 retracts, the upper cylinder 1 and lower cylinder 2 of the detector move closer together, the upper arm 12 and lower arm 22 retract, and the protective plate 51 also retracts. At this time, the debris on the V-shaped collection area will automatically fall off due to the retraction of the protective plate 51, without the need for additional cleaning (some damp debris will adhere to the protective plate 51, but this will not affect the subsequent use of the detector). After the protective plate 51 retracts, it surrounds the outer perimeter of the detector, providing protection for the detector.

[0036] Therefore, in this embodiment, the staggered upper arm 12 and lower arm 22 form a " / " shaped support structure in cross-section and a three-dimensional X-shaped support structure in the circumferential direction. Combined with the deployment method of the upper arm 12 and lower arm 22, compared to the existing technology using airbag fixation, this device design can change surface contact to rigid multi-point contact, forming a constraint in the circumferential direction, enhancing the contact stability between the detector and the well wall, and thus improving the stability of vibration wave transmission. Simultaneously, the protective plate 51, which deploys synchronously with the upper arm 12 and lower arm 22, can be used to guide well wall debris to fall and increase the contact area between the detector and the well wall, further improving the efficiency of vibration wave transmission to the detector, making the detector's detection of vibration waves more accurate.

[0037] Example 2: Refer to Figures 7-14A downhole geophone for geophysical exploration includes an upper geophone cylinder 1 and a lower geophone cylinder 2 connected together. It also includes a driving component for driving the upper geophone cylinder 1 and the lower geophone cylinder 2 to move closer or further apart. A flexible protective sleeve 13 is connected between the upper geophone cylinder 1 and the lower geophone cylinder 2 to protect the area between them. Upper arms 12 and lower arms 22, respectively connected to the upper geophone cylinder 1 and the lower geophone cylinder 2, are rotated. When the opposing upper arms 12 and lower arms 22 are extended, they form a " / " shape. The upper arm 12 and lower arm 22, which are adjacent to each other on the same horizontal plane, form a V-shape that opens to one side and together form a three-dimensional X-shaped support in the circumferential direction. The mounting slots 3 are respectively opened on the upper cylinder 1 and lower cylinder 2 of the detector, and the upper arm 12 and lower arm 22 are respectively connected to the corresponding mounting slots 3. Multiple telescopic rods 5 are respectively set on the upper cylinder 1 and lower cylinder 2 of the detector, and protective plates 51 are installed on the telescopic rods 5. When the upper arm 12 and lower arm 22 are extended, the protective plates 51 are extended accordingly.

[0038] The driving component includes a cylinder 10, which is installed between the upper cylinder 1 and the lower cylinder 2 of the detector. A long rack 14 is connected between the upper cylinder 1 and the lower cylinder 2 of the detector, and limit blocks 141 are fixedly connected to both ends of the long rack 14. A gear 4 is rotatably connected in the mounting groove 3. One end of the upper arm 12 and the lower arm 22 are respectively fixedly connected to the corresponding gear 4. The two ends of the long rack 14 pass through guide holes 3 opened on the upper cylinder 1 and the lower cylinder 2 of the detector. 4 passes through the mounting groove 3 and meshes with the corresponding gear 4; the mounting groove 3 includes a mounting cavity 30, a receiving groove 31 connected to the mounting cavity 30, and a sliding groove 32 opened in the receiving groove 31. A limiting flange 33 is formed between the sliding groove 32 and the mounting cavity 30. The setting of the limiting flange 33 can limit the displacement stroke of the long rack 14 in the upper cylinder 1 or the lower cylinder 2 of the detector, so that the long rack 14 can drive the upper arm 12 and the lower arm 22 to fully unfold. The upper arm 12 and the lower arm 22 are provided with clearance grooves 40. The long rack 14 passes through the clearance grooves 40 and passes through the upper arm 12 and the lower arm 22. The clearance grooves 40 can prevent the upper arm 12 and the lower arm 22 from colliding with the long rack 14 when they rotate.

[0039] The two ends of multiple telescopic rods 5 are rotatably connected between the upper arm rod 12 and the lower arm rod 22 respectively. When the upper arm rod 12 and the lower arm rod 22 are extended, the protective plate 51 is attached to the well wall.

[0040] A triangular structure area 200 is formed between the upper arm 12, the lower arm 22, and the telescopic arm 5.

[0041] A tie rod 52 is fixedly connected to the outer surface of the protective plate 51.

[0042] Unlike Embodiment 1, in this embodiment, when the cylinder 10 drives the upper cylinder 1 and the lower cylinder 2 of the detector to move away from each other, the unfolding of the upper arm 12 and the lower arm 22 is driven by the relative movement of the upper cylinder 1 and the lower cylinder 2 of the detector through the long rack 14. The two ends of the long rack 14 respectively mesh with the gear 4 located in the upper cylinder 1 and the gear 4 located in the lower cylinder 2 of the detector, so that the upper arm 12 and the lower arm 22 unfold. After deployment, the upper arm 12 and lower arm 22 form a symmetrical three-dimensional X-shaped support structure to fix the detector to the well wall. At the same time, the protective plate 51 is deployed vertically to approach and contact the well wall, while the tie rod 52 on the outer wall of the protective plate 51 is driven into the well wall to further support the detector, making the detector more stable on the well wall. The vertically extending protective plate 51 can restrict the well wall near the detector, reducing the probability of the well wall falling and hitting the detector. In addition, the vertically extending protective plate 51, together with the upper arm 12 and the lower arm 22, forms a triangular structure area 200, which can provide rigid multi-point support and overall stability after the detector is fixed to the well wall.

[0043] When the protective plate 51 is retracted, multiple protective plates 51 wrap around the outer periphery of the detector, providing protection for the detector.

[0044] In one embodiment, refer to Figure 7 , Figure 9 , Figure 10 , Figure 12 Multiple elastic ropes 63 are connected between the upper arm 12 and the upper end of the detector upper cylinder 1. A protective net 64 is fixedly connected between adjacent elastic ropes 63. An elastic rope 65 is fixedly connected to the upper edge of the protective net 64. When the upper arm 12 is extended, the protective net 64 is pulled open. When the upper arm 12 is retracted, the protective net 64 is wrapped around the outer periphery of the detector upper cylinder 1 by the elastic rope 65.

[0045] A limiting cavity 6 is provided at the upper end of the detector upper cylinder 1. A sliding sleeve 61 is slidably connected in the limiting cavity 6. A spring 62 is provided between the end of the sliding sleeve 61 and the bottom wall of the limiting cavity 6. The end of the elastic rope 63 away from the upper arm rod 12 is connected to the sliding sleeve 61.

[0046] By setting up a protective net 64, when the upper arm 12 and the lower arm 22 are extended, the increased distance between the upper arm 12 and the upper cylinder 1 of the detector will pull the elastic rope 63, thereby causing the protective net 64 to extend on the upper cylinder 1 of the detector to protect the top of the detector. When the protective net 64 is extended, it will provide downward pressure on the sliding sleeve 61, causing the sliding sleeve 61 to move downward into the limiting sliding cavity 6. Because of the spring 62, when debris falls from above the detector, the spring 62 can provide some cushioning and reduce the vibration caused by the falling debris hitting the detector.

[0047] When the upper boom 12 retracts, the protective net 64 retracts accordingly. At the same time, the elastic rope 65 set at the lower edge of the protective net 64 contracts, causing the lower edge of the protective net 64 to come close to the outer periphery of the upper cylinder 1 of the detector, reducing the extended area of ​​the protective net 64 after it is retracted. On the one hand, this reduces the area of ​​the protective net 64 after it is retracted, avoiding interference with the detector's up-and-down movement downhole. On the other hand, when the protective net 64 retracts, the downward pressure on the sliding sleeve 61 decreases, and the spring 62 pushes the sliding sleeve 61 upward, increasing the slope of the protective net 64. This allows debris on the protective net 64 to slide off automatically, achieving the function of automatic debris removal, and preventing debris from causing significant interference to the detector or jamming the upper boom 12 and lower boom 22.

[0048] Furthermore, the upper arm 12 is connected to the sliding sleeve 61 on the upper cylinder 1 of the detector via an elastic rope 63. Therefore, when the upper cylinder 1 and the lower cylinder 2 of the detector are relatively far apart, the upper arm 12, due to the pull of the elastic rope 63, will cause the gear 4 in the lower cylinder 2 of the detector to mesh with the long rack 14 first, driving the lower arm 22 to rotate and unfold. The priority unfolding of the lower arm 22 allows the tie rods 52 on the outer periphery of the protective plate 51 to be driven into the well wall one by one, avoiding simultaneous driving and generating greater resistance. This allows the protective plate 51, as well as the upper arm 12 and the lower arm 22, to be firmly in contact with the well wall, improving the stability of the detector when it is fixed.

[0049] A connecting rod 7 is installed in the upper cylinder 1 of the detector. One end of the connecting rod 7 is fixed to the bottom wall of the limiting slide cavity 6, and the other end extends to the outside of the upper cylinder 1 of the detector to be connected to the external rope. At the same time, the connecting rod 7 is hollow to facilitate the routing of the detector's cables and air pipes.

[0050] In an alternative embodiment, the driving component refers to a mechanical part that can provide a power source for linear reciprocating motion. It can be implemented by a hydraulic cylinder, an electric push rod, or a screw structure driven by a motor. For example, a ball screw driven by a servo motor can drive the nut seat to move linearly. This is mainly to achieve the relative displacement between the upper cylinder 1 and the lower cylinder 2 of the detector.

[0051] This invention addresses the core defect of traditional airbag hollow elastic structures that absorb seismic waves, leading to signal errors. Both embodiments of this invention employ a mechanical transmission and rigid arm support system, eliminating the interference of compressible materials on signals through structural design.

[0052] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any way. Although the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make some modifications or alterations to the above-described technical content to create equivalent embodiments without departing from the scope of the present invention. Any simple modifications, equivalent changes, and alterations made to the above embodiments based on the technical essence of the present invention without departing from the scope of the present invention shall still fall within the scope of the present invention.

Claims

1. A downhole geophone for geophysical exploration, comprising a connected upper geophone cylinder (1) and a lower geophone cylinder (2), characterized in that, Also includes: A driving component is used to drive the upper cylinder (1) and the lower cylinder (2) of the detector to move closer or further apart; The upper arm (12) and lower arm (22) connected to the upper cylinder (1) and lower cylinder (2) of the detector are rotated respectively. When the upper arm (12) and lower arm (22) are unfolded, they form a " / " shape and form a three-dimensional X-shaped support in the circumferential direction. Mounting slots (3) are respectively opened on the upper cylinder (1) and lower cylinder (2) of the detector, and the upper arm (12) and lower arm (22) are respectively connected in the corresponding mounting slots (3); Multiple telescopic rods (5) are respectively installed on the upper cylinder (1) and lower cylinder (2) of the detector, and protective plates (51) are installed on the telescopic rods (5). When the upper arm (12) and lower arm (22) are deployed, the protective plate (51) is deployed accordingly; The driving component includes a cylinder (10), which is installed between the upper cylinder (1) and the lower cylinder (2) of the detector; Multiple racks one (11) and rack two (21) are fixedly connected to the upper cylinder (1) and lower cylinder (2) of the detector respectively, and the racks one (11) and rack two (21) are arranged alternately. The mounting groove (3) is rotatably connected to a gear (4). One end of the upper arm (12) and lower arm (22) is fixedly connected to the corresponding gear (4). One end of the rack one (11) and rack two (21) passes through the mounting groove (3) and meshes with the corresponding gear (4).

2. The downhole geophone for geophysical exploration according to claim 1, characterized in that, Multiple telescopic rods (5) are rotatably connected between the upper arm rod (12) and the lower cylinder of the detector (2) and the lower arm rod (22) and the upper cylinder of the detector (1), forming a triangular structure area (20).

3. A downhole geophone for geophysical exploration according to claim 2, characterized in that, The mounting groove (3) includes a mounting cavity (30), a storage groove (31) connected to the mounting cavity (30), and a sliding groove (32) opened in the storage groove (31) and connected to the mounting cavity (30). The upper arm (12) and the lower arm (22) are located in the storage groove (31) after being retracted. The upper cylinder (1) and the lower cylinder (2) of the detector are both provided with guide holes (34). The guide holes (34) are connected to the mounting cavity (30). The rack one (11) and rack two (21) slide in the sliding groove (32) through the guide holes (34).

4. A downhole geophone for geophysical exploration, comprising a connected upper geophone cylinder (1) and a lower geophone cylinder (2), characterized in that, Also includes: A driving component is used to drive the upper cylinder (1) and the lower cylinder (2) of the detector to move closer or further apart; The upper arm (12) and lower arm (22) connected to the upper cylinder (1) and lower cylinder (2) of the detector are rotated respectively. When the upper arm (12) and lower arm (22) are unfolded, they form a " / " shape and form a three-dimensional X-shaped support in the circumferential direction. Mounting slots (3) are respectively opened on the upper cylinder (1) and lower cylinder (2) of the detector, and the upper arm (12) and lower arm (22) are respectively connected in the corresponding mounting slots (3); Multiple telescopic rods (5) are respectively installed on the upper cylinder (1) and lower cylinder (2) of the detector, and protective plates (51) are installed on the telescopic rods (5). When the upper arm (12) and lower arm (22) are deployed, the protective plate (51) is deployed accordingly; The driving component includes a cylinder (10), which is installed between the upper cylinder (1) and the lower cylinder (2) of the detector; A long rack (14) is connected between the upper cylinder (1) and the lower cylinder (2) of the detector, and a limit block (141) is fixedly connected to both ends of the long rack (14). The mounting groove (3) is rotatably connected to a gear (4). One end of the upper arm (12) and the lower arm (22) are respectively fixedly connected to the corresponding gear (4). The two ends of the long rack (14) pass through the guide holes (34) opened on the upper cylinder (1) and the lower cylinder (2) of the detector and enter the mounting groove (3) respectively, and mesh with the corresponding gear (4). The mounting groove (3) includes a mounting cavity (30), a storage groove (31) connected to the mounting cavity (30), and a sliding groove (32) formed in the storage groove (31). A limiting flange (33) is formed between the sliding groove (32) and the mounting cavity (30).

5. A downhole geophone for geophysical exploration according to claim 4, characterized in that, The two ends of the multiple telescopic rods (5) are respectively rotatably connected between the upper arm rod (12) and the lower arm rod (22). When the upper arm rod (12) and the lower arm rod (22) are extended, the protective plate (51) is attached to the well wall.

6. A downhole geophone for geophysical exploration according to claim 5, characterized in that, A triangular structure area 200 is formed between the upper arm (12), the lower arm (22), and the telescopic rod (5).

7. A downhole geophone for geophysical exploration according to claim 4, characterized in that, A tie rod (52) is fixedly connected to the outer surface of the protective plate (51).

8. A downhole geophone for geophysical exploration according to claim 7, characterized in that, Multiple elastic ropes (63) are connected between the upper arm (12) and the upper end of the detector upper cylinder (1). A protective net (64) is fixedly connected between adjacent elastic ropes (63). An elastic rope (65) is fixedly connected to the upper edge of the protective net (64). When the upper arm (12) is extended, the protective net (64) is pulled open. When the upper arm (12) is retracted, the protective net (64) is wrapped around the outer periphery of the detector upper cylinder (1) by the elastic rope (65).

9. A downhole geophone for geophysical exploration according to claim 8, characterized in that, The upper end of the detector upper cylinder (1) is provided with a limiting slide cavity (6), and a sliding sleeve (61) is slidably connected in the limiting slide cavity (6). A spring (62) is provided between the end of the sliding sleeve (61) and the bottom wall of the limiting slide cavity (6). The end of the elastic rope (63) away from the upper arm rod (12) is connected to the sliding sleeve (61).

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