A drainage robot

Abstract

The present invention relates to a drainage robot. The drainage robot includes a sealing system and a braking system; the sealing system includes: a sealing cylinder having a central flow channel; an elastic sealing component sleeved on the sealing cylinder, the elastic sealing component being used to press against the inner wall of an oil pipe; a flow channel valve, being used to control the opening and closing of the central flow channel; the braking system includes: a braking cylinder; a driving device, being in the braking cylinder, the transmission shaft of the driving device being in transmission connection with the inner cylinder; a transmission cylinder, being fixed on the transmission shaft, the cylinder wall of the transmission cylinder having a variable diameter surface; a brake block, being arranged outside the braking cylinder; a second resetting elastic member, being arranged between the braking cylinder and the corresponding brake block, being used to apply an elastic force to the brake block to make it move away from the braking cylinder; a transmission hook, being fixed on the inner side of the corresponding brake block, the transmission hook having a hook head, and the hook head being hooked on the variable diameter surface.

Description

Technical Field

[0001] The invention relates to a drainage robot and belongs to the field of oil and gas exploitation. Background Art

[0002] Plunger gas lift has been widely used as a water drainage gas production technology. This method can reduce bottom hole liquid accumulation and extend the production time of gas wells. Moreover, it can be used in oil and gas wells that are prone to wax and scale formation, eliminating the process of cleaning wax and scale.

[0003] The plungers currently in operation basically ignore speed control. During the drainage process, due to the continuous increase in well depth, when the plunger descends, it is in a state of nearly free fall. When the plunger touches the liquid surface or reaches the bottom of the well, it will inevitably produce excessive impact on itself and the bottom of the well buffer, thereby destroying the plunger or the buffer and causing serious downhole accidents. When the plunger is ascending, the high-pressure gas at the bottom of the well forms a continuous lifting force on the plunger. During the process of continuous discharge of the liquid on the top of the plunger, the plunger will continue to accelerate upward. When it reaches the wellhead position, it will also collide with the wellhead blowout preventer due to excessive speed, damaging the plunger or the wellhead blowout preventer, posing a major safety hazard. Summary of the invention

[0004] The object of the present invention is to provide a drainage robot to solve the technical problem in the prior art that a plunger will generate a large impact when moving upward and downward.

[0005] To achieve the above purpose, the technical solution of the drainage robot of the present invention is:

[0006] Drainage robot, including sealing system and braking system;

[0007] The sealing system comprises a sealing cylinder and a flow channel valve, wherein the sealing cylinder has a central flow channel; an elastic sealing assembly is sleeved on the sealing cylinder, wherein the elastic sealing assembly comprises a first resetting elastic member and a sealing body, and under the action of the first resetting elastic member, the sealing body is used to press against the inner wall of the oil pipe; the flow channel valve comprises an outer cylinder and an inner cylinder, wherein the outer cylinder is connected to the lower part of the sealing cylinder, and the inner cylinder can move relative to the outer cylinder to control the opening and closing of the central flow channel;

[0008] The braking system includes a brake cylinder body, in which a driving device and a transmission cylinder are arranged, the driving device includes a driving motor and a transmission shaft, the driving motor is connected to the inner cylinder through the transmission shaft; the transmission cylinder is fixed on the transmission shaft, and a variable diameter surface is provided in the cylinder wall of the transmission cylinder; a brake block is provided on the outside of the brake cylinder body, at least two brake blocks are arranged along the circumference of the brake cylinder body, a brake convex portion is provided on the outer side surface of the brake block, and both side surfaces of the brake convex portion in the axial direction of the brake cylinder body are inclined surfaces; a transmission hook is provided on the inner side of the brake block, and the transmission hook has a hook head, and the hook head is hooked on the variable diameter surface; a second reset elastic member is provided between the brake cylinder body and the corresponding brake block, and the second reset elastic member is used to apply an elastic force to the brake block to keep it away from the brake cylinder body.

[0009] The beneficial effect is that the drainage robot of the present invention can adjust the operating speed of the drainage robot in real time according to the current operating status and well conditions, effectively avoiding excessive impact force when the drainage robot reaches the extreme position, preventing the drainage robot from being damaged, and increasing the service life of the drainage robot. At the same time, it protects the bottom of the well and the wellhead equipment, greatly reducing the safety production accidents caused by high-speed impacts.

[0010] As a further improvement, the drive motor drives the transmission shaft to rotate along the circumference of the brake cylinder, and the inner cylinder rotates relative to the outer cylinder under the drive of the transmission shaft; a reducing groove is provided at the end of the transmission cylinder, and the reducing groove has at least two transmission groove wall segments in the circumference of the transmission cylinder, and the transmission groove wall segments gradually approach or move away from the center line of the transmission cylinder in the circumference of the transmission cylinder, and the groove wall surface of the transmission groove wall segment constitutes the reducing surface.

[0011] As a further improvement, the transmission groove wall section includes a first groove wall unit and a second groove wall unit, and the change rate of the first groove wall unit approaching or moving away from the center line of the transmission cylinder is smaller than the change rate of the second groove wall unit approaching or moving away from the center line of the transmission cylinder.

[0012] The beneficial effect is that such a design can quickly adjust the movement of the brake block along the radial direction of the brake cylinder, thereby realizing rapid opening and closing of the brake system.

[0013] As a further improvement, a driving block is convexly provided on the outer circumferential surface of the transmission shaft, a shaft mounting groove is provided at the lower part of the inner cylinder, a fan-shaped groove is provided on the groove wall of the shaft mounting groove, the shaft mounting groove is adapted to the transmission shaft, and the driving block moves circumferentially along the transmission shaft in the fan-shaped groove.

[0014] As a further improvement, at least two driving blocks are arranged at intervals along the circumference of the transmission shaft, and the fan-shaped grooves correspond to the driving blocks one by one.

[0015] The beneficial effect is that such a design can ensure uniform force during the driving process.

[0016] As a further improvement, the sealing system also includes a rubber sleeve, which is mounted on the sealing cylinder body, and the rubber sleeve and the sealing cylinder body form an annular cavity; a pressure transmission channel is provided on the sealing cylinder body, one end of the pressure transmission channel is connected to the annular cavity, and the other end of the pressure transmission channel is located below the elastic sealing assembly and is connected to the outside of the sealing cylinder body; a one-way valve is provided on the pressure transmission channel, the one-way valve includes a valve core and a third reset elastic member, the third reset elastic member is used to apply an elastic force to the valve core to close the pressure transmission channel, and a pressure relief hole is provided on the valve core, and the pressure relief hole extends through the axial direction of the valve core.

[0017] The beneficial effect is that since the rubber sleeve is relatively soft, the sealing performance between the rubber sleeve and the inner wall of the oil pipe is better, thereby ensuring sufficient lifting pressure.

[0018] As a further improvement, a pressure transmission tube is provided on the sealing cylinder, and the tube cavity of the pressure transmission tube constitutes the pressure transmission channel.

[0019] The beneficial effect is that since the pressure transmission pipe can be conveniently arranged on the sealing cylinder, it is beneficial to form a pressure transmission channel.

[0020] As a further improvement, the elastic sealing components are provided in two groups, and the rubber cylinder is located between the two groups of elastic sealing components.

[0021] The beneficial effect is: the sealing performance of the drainage robot is further guaranteed.

[0022] As a further improvement, the drive motor drives the transmission shaft to move axially along the brake cylinder body, and the inner cylinder slides axially along the transmission shaft relative to the outer cylinder under the drive of the transmission shaft; the transmission cylinder has a center hole, the center hole includes a large hole section, a small hole section and a tapered hole section, the tapered hole section is connected between the large hole section and the small hole section, and a guide groove connecting the inside and outside of the transmission cylinder is provided on the hole wall of the center hole, the guide groove extends along the axial direction of the transmission cylinder, and the inner wall surface of the tapered hole section constitutes the variable diameter surface.

[0023] As a further improvement, at least one end of the guide groove is provided with a hook through hole, and the hook through hole is used for the hook to pass through to enter the central hole of the transmission cylinder.

[0024] The beneficial effect is that such a design makes it easy to install the hook head into the central hole of the transmission cylinder. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 This is a schematic structural diagram of Embodiment 1 of the drainage robot of the present invention;

[0026] Figure 2 for Figure 1 Structural diagram of the sealing system;

[0027] Figure 3 for Figure 2 Schematic diagram of the structure of the one-way valve;

[0028] Figure 4 for Figure 1 Schematic diagram of the structure when the brake system is closed;

[0029] Figure 5 for Figure 1 A schematic diagram of the structure in which the brake pad is at the coupling when the middle brake system is turned on;

[0030] Figure 6 for Figure 1 A schematic diagram of the structure in which the brake block is above the coupling when the middle brake system is turned on;

[0031] Figure 7 for Figure 4 A schematic diagram of the structure of the middle and upper brake cylinder;

[0032] Figure 8 for Figure 4 A schematic diagram of the structure of the middle brake block and the transmission hook;

[0033] Fig. 9 for Figure 4 A schematic diagram of the structure of the middle transmission cylinder;

[0034] Fig.10 for Fig. 9 Bottom view of

[0035] Fig.11 for Figure 4 Middle AA section view;

[0036] Fig.12 for Figure 2 A schematic diagram of the structure of the inner cylinder of the mid-flow valve;

[0037] Fig.13 for Fig.12 Bottom view of

[0038] Fig.14 for Figure 4 A schematic diagram of the structure of the drive sleeve at the upper end of the middle transmission shaft;

[0039] Fig.15 for Figure 1 Schematic diagram of the structure of the drainage robot working downward;

[0040] Fig.16 for Figure 1 Schematic diagram of the structure of the drainage robot hovering or braking and decelerating underground;

[0041] Fig.17 for Figure 1 Schematic diagram of the structure of the drainage robot working upward;

[0042] Fig.18This is a schematic structural diagram of the braking system of the drainage robot of Example 2 of the present invention when it is closed;

[0043] Fig.19 for Fig.18 A schematic diagram of the structure in which the brake pad is at the coupling when the middle brake system is turned on;

[0044] Fig. 20 for Fig.18 A schematic diagram of the structure in which the brake block is above the coupling when the middle brake system is turned on;

[0045] Fig.21 for Fig.18 A schematic diagram of the structure of the middle and upper brake cylinder;

[0046] Fig. 22 for Fig.18 A schematic diagram of the structure of the middle brake block and the transmission hook;

[0047] Fig.23 for Fig.18 A schematic diagram of the structure of the middle transmission cylinder;

[0048] Figures 1 to 17 In: 1001, fishing head; 1002, sealing system; 1003, braking system; 1004, speed sensor; 1005, battery pack; 1006, centralizer; 1007, signal transmission device; 41, upper sealing cylinder; 42, upper sealing limit sleeve; 43, third compression spring positioning groove; 44, lower sealing limit sleeve; 45, rubber cylinder; 46, annular cavity; 47, lower sealing cylinder; 48, flow channel valve; 49, first return compression spring; 50, sealing body; 51, pressure transmission pipe; 52, one-way valve; 53, first limit protrusion; 54, elastic sealing assembly; 55, third return compression spring; 56, valve core; 57, annular rubber pad; 58, pressure relief hole; 59, inner cylinder; 60, flow channel port; 61, shaft mounting groove; 62, fan-shaped groove; 63, drive sleeve; 64 , driving block; 101, driving bin; 102, driving motor; 103, lower brake cylinder; 104, coupling; 105, oil pipe; 106, upper brake cylinder; 107, transmission shaft; 108, lower brake limit sleeve; 109, second return compression spring; 110, coupling gap; 111, transmission hook; 112, brake block; 113, transmission cylinder; 114, upper brake limit sleeve; 115, retaining ring; 116, avoidance hole; 117, first compression spring positioning groove; 118, limit groove; 119, hook head; 120, brake convex part; 121, second compression spring positioning groove; 122, second limit protrusion; 123, small diameter section; 124, large diameter section; 125, first slot wall unit; 126, second slot wall unit; 127, stop hole; 128, transmission slot wall section;

[0049] Figures 18 to 23In: 11. driving motor; 12. lower brake cylinder; 13. driving chamber; 14. screw nut mechanism; 15. oil pipe; 16. transmission shaft; 17. joint; 18. coupling gap; 19. lower brake limit sleeve; 20. transmission cylinder; 21. transmission hook; 22. brake block; 23. reset compression spring; 24. upper brake limit sleeve; 25. upper brake cylinder; 26. avoidance hole; 27. first compression spring positioning groove; 28. limiting groove; 29. ​​hook head; 30. braking convex part; 31. second compression spring positioning groove; 32. limiting protrusion; 33. connecting seat; 34. small hole section; 35. tapered hole section; 36. large hole section; 37. guide groove; 38. hook head perforation. DETAILED DESCRIPTION

[0050] In order to make the purpose, technical scheme and advantages of the present invention clearer, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention, that is, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments. The components of the embodiments of the present invention described and shown in the drawings herein can be arranged and designed in various different configurations.

[0051] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the invention claimed for protection, but merely represents selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without making creative work are within the scope of protection of the present invention.

[0052] It should be noted that the terms such as "first" and "second" and other relational terms that may appear are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, terms such as "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that the process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the sentence "including one..." do not exclude the existence of other identical elements in the process, method, article or device including the elements. In addition, the terms "front", "back", "up", "down", "left" and "right" are based on the orientation and positional relationship shown in the accompanying drawings, only for the convenience of describing the present invention, rather than indicating that the device or component referred to must have a specific orientation, and therefore cannot be understood as a limitation of the present invention.

[0053] The features and performance of the present invention are further described in detail below in conjunction with the embodiments.

[0054] Embodiment 1 of the drainage robot of the present invention:

[0055] like Figure 1 As shown, the drainage robot includes a salvage head 1001, a sealing system 1002, a braking system 1003, a speed sensor 1004, a battery pack 1005, a centralizer 1006 and a signal transmission device 1007, which are arranged from top to bottom. The battery pack 1005 is used to provide power to the braking system 1003, the speed sensor 1004 and the signal transmission device 1007.

[0056] In this embodiment, Figure 2 , Figure 3 as well as Fig.15 As shown, the sealing system 1002 includes a sealing cylinder, which is formed by threading an upper sealing cylinder 41 and a lower sealing cylinder 47, and the inner cavities of the upper and lower sealing cylinders constitute a central flow channel; the upper sealing cylinder 41 and the lower sealing cylinder 47 are respectively sleeved with elastic sealing components 54, and the lower sealing cylinder 47 is also sleeved with a rubber cylinder 45, and the rubber cylinder 45 is located between the two sets of elastic sealing components 54. In other embodiments, the rubber cylinder can be arranged above the elastic sealing component on the upper sealing cylinder.

[0057] In this embodiment, an annular step is provided on the lower sealing cylinder 47 , the lower end of the rubber cylinder 45 abuts on the annular step, and the upper end of the rubber cylinder 45 abuts on the lower end surface of the upper sealing cylinder 41 , so as to facilitate the installation of the rubber cylinder 45 .

[0058] In this embodiment, the structures of the two sets of elastic sealing components 54 are the same. Taking the upper elastic sealing component 54 as an example, the upper end of the upper sealing cylinder 41 is threadedly connected with the upper sealing limit sleeve 42, and the lower part of the upper sealing limit sleeve 42 and the upper sealing cylinder 41 form an upper limit ring groove; the lower end of the upper sealing cylinder 41 is threadedly connected with the lower sealing limit sleeve 44, and the upper part of the lower sealing limit sleeve 44 and the upper sealing cylinder 41 form a lower limit ring groove. The elastic sealing component includes a first return spring 49 and a sealing body 50. Under the action of the first return spring 49, the sealing body 50 is used to press against the inner wall of the oil pipe; in this embodiment, four sealing bodies 50 are arranged along the circumference of the upper sealing cylinder 41, and the two ends of each sealing body 50 are respectively provided with a first limit protrusion 53, and the two first limit protrusions 53 of the sealing body 50 are respectively limited and assembled in the upper limit ring groove and the lower limit ring groove, so that the sealing body 50 is floatingly assembled on the upper sealing cylinder 41.

[0059] In this embodiment, each sealing body 50 corresponds to two first return compression springs 49, and the two first return compression springs 49 are arranged at intervals along the axial direction of the upper sealing cylinder 41 to ensure that the sealing body 50 can be stably pressed against the inner wall of the oil pipe. Among them, the first return compression spring 49 constitutes a first return elastic member. In other embodiments, each sealing body can correspond to one or more than three first return compression springs.

[0060] like Figure 2 As shown, the sealing body 50 and the upper sealing cylinder 41 are both provided with a third compression spring positioning groove 43, and the third compression spring positioning groove 43 is arranged corresponding to the first return compression spring 49. The outer end of the first return compression spring 49 is located in the third compression spring positioning groove 43 on the sealing body 50, and the inner end of the first return compression spring 49 is located in the third compression spring positioning groove 43 on the upper sealing cylinder 41, so as to ensure the stability of the first return compression spring 49 during the expansion and contraction process.

[0061] In this embodiment, an elastic sheet is provided on the inner side of the lower side of any two adjacent sealing bodies 50, and the width of the elastic sheet along the circumference of the sealing cylinder is greater than the gap between the two adjacent sealing bodies 50, so as to reduce the axial leakage of liquid from the inside of the sealing body 50 along the upper cylinder 41, and the elastic sheet 54 can be tightly attached to the inner side of the sealing body 50 to further reduce leakage.

[0062] like Figure 2 , Figure 3 as well as Fig.15 As shown, the rubber cylinder 45 and the upper sealing cylinder 41 form an annular cavity 46; the lower sealing cylinder 47 is provided with a pressure transmission tube 51, the lumen of the pressure transmission tube 51 constitutes a pressure transmission channel, one end of the pressure transmission channel is connected to the annular cavity 46, and the other end of the pressure transmission channel is located below the elastic sealing component 54 on the lower sealing cylinder 47 and is connected to the outside of the sealing cylinder. When the high-pressure gas does not enter the annular cavity 46, the outer diameter of the rubber cylinder 45 is smaller than the outer diameter of the elastic sealing component 54.

[0063] In this embodiment, a one-way valve 52 is provided on the pressure transmission channel, and the one-way valve 52 includes a valve core 56 and a third return compression spring 55, and the third return compression spring 55 is used to apply an elastic force to the valve core 56 to close the pressure transmission channel; the valve core 56 is provided with a pressure relief hole 58, and the pressure relief hole 58 extends through the axial direction of the valve core 56. Among them, the third return compression spring 55 constitutes a third return elastic member.

[0064] In this embodiment, the valve core 56 is a screw-shaped structure, and an annular rubber pad 57 is sleeved on the valve core 56 to ensure sealing performance.

[0065] like Figure 2 , Fig.12 and Fig.13As shown, a flow channel valve 48 is provided at the lower part of the lower sealing cylinder 47, and the flow channel valve 48 includes an outer cylinder and an inner cylinder 59, and a flow channel opening 60 is provided on the cylinder wall of the outer cylinder and the inner cylinder 59. The outer cylinder is connected to the lower part of the lower sealing cylinder 47, and the inner cylinder 59 is driven by the transmission shaft 107 to be rotatably assembled in the outer cylinder. Among them, a shaft mounting groove 61 is provided at the lower part of the inner cylinder 59, and a fan-shaped groove 62 is provided on the groove wall of the shaft mounting groove 61, and two fan-shaped grooves 62 are evenly spaced along the circumferential direction of the shaft mounting groove 61. The specific structure and working principle of the above-mentioned flow channel valve are prior art and will not be described in detail here. In other embodiments, the number of fan-shaped grooves can be set as needed.

[0066] The working process of the sealing system 1002 is as follows: when descending, the rubber cylinder 45 always remains in its original state. Since the diameter of the elastic sealing component 54 is larger than that of the rubber cylinder 45, the elastic sealing component 54 can play a good protective role on the rubber cylinder 45, avoiding the rubber cylinder 45 from rubbing against the inner wall of the oil pipe when descending; when the pressure is suppressed underground, the flow channel valve 48 is closed underground, and the pressure transmission pipe 51 continues to fill the underground high-pressure gas into the annular cavity 46, so that the rubber cylinder 45 expands radially, and then closely adheres to the inner wall of the oil pipe to form a seal. Since the rubber cylinder 45 is relatively soft, the sealing performance of the rubber cylinder 45 and the inner wall of the oil pipe is good, ensuring sufficient lifting pressure. During the upward process, when the internal and external pressures of the rubber cylinder 45 reach equilibrium, the rubber cylinder 45 needs to return to its original state due to its own elasticity, so that the gas in the annular cavity 46 is slowly discharged through the pressure relief hole 58, and then the rubber cylinder 45 no longer rubs against the inner wall of the oil pipe. In addition, it can reduce the friction between the rubber cylinder and the inner wall of the oil pipe, reduce the risk of rubber cylinder damage, and extend the service life of the rubber cylinder.

[0067] like Figure 4 As shown, the brake system 1003 includes a brake cylinder, which is arranged in the oil pipe 105 along the up and down direction. The brake cylinder includes an upper brake cylinder 106 and a lower brake cylinder 103, and the upper brake cylinder 106 and the lower brake cylinder 103 are threadedly connected together.

[0068] In this embodiment, the inner cavity of the lower brake cylinder 103 constitutes a driving chamber 101, and a driving motor 102 and a coupling 104 are arranged in the driving chamber 101. The driving motor 102 is connected to the transmission shaft 107 through the coupling 104 to drive the transmission shaft 107 to move circumferentially along the brake cylinder.

[0069] In this embodiment, a transmission cylinder 113 is disposed in the inner cavity of the upper brake cylinder 106, and the transmission cylinder 113 is fixed on the transmission shaft 107 to move along the circumferential direction of the brake cylinder with the transmission shaft 107. Figure 4 and Fig.10As shown, the transmission cylinder 113 has a stop hole 127, which extends axially along the transmission cylinder 113. The transmission cylinder 113 is mounted on the transmission shaft 107, and the transmission cylinder 113 and the transmission shaft 107 are assembled together to stop rotation, and the transmission cylinder 113 is limited by the retaining ring 115 to limit the axial movement of the transmission cylinder 113 on the transmission shaft 107.

[0070] like Figure 4 and Figure 7 As shown, a lower brake limit sleeve 108 and an upper brake limit sleeve 114 are provided on the upper brake cylinder 106 , and an installation groove is formed between the two brake limit sleeves. A brake block 112 is installed in the installation groove. The brake block 112 is arranged outside the upper brake cylinder 106 , and two brake blocks 112 are arranged along the circumference of the upper brake cylinder 106 .

[0071] In this embodiment, the bottom of the installation groove is provided with an avoidance hole 116, a first compression spring positioning groove 117 and a limiting groove 118; each brake block 112 corresponds to one avoidance hole 116, and the avoidance hole 116 is located in the middle position of the installation groove in the axial direction of the upper brake cylinder 106; each brake block 112 corresponds to two first compression spring positioning grooves 117, and the two first compression spring positioning grooves 117 are located on both sides of the avoidance hole 116 in the axial direction of the upper brake cylinder 106; each brake block 112 corresponds to two limiting grooves 118, and the two limiting grooves 118 are located on both sides of the avoidance hole 116 in the axial direction of the upper brake cylinder 106. Among them, the first compression spring positioning groove 117 is between the avoidance hole 116 and the corresponding limiting groove 118.

[0072] like Figure 4 and Figure 8 As shown, the brake block 112 is provided with second limiting protrusions 122 at both ends of the upper brake cylinder 106 in the axial direction. After the second limiting protrusion 122 is inserted into the limiting groove 118, the lower brake limiting sleeve 108 and the upper brake limiting sleeve 114 cooperate to make the brake block 112 float and be assembled on the upper brake cylinder 106.

[0073] In this embodiment, a second compression spring positioning groove 121 is provided on the inner side surface of the brake block 112, and two second compression spring positioning grooves 121 are provided, and the second compression spring positioning grooves 121 are arranged one-to-one with the first compression spring positioning groove 117; a second return compression spring 109 is provided between the brake block 112 and the upper brake cylinder 106, and the second return compression spring 109 is used to apply an elastic force to the brake block 112 to make it move away from the upper brake cylinder 106; one end of the second return compression spring 109 is installed in the first compression spring positioning groove 117, and the other end of the second return compression spring 109 is installed in the second compression spring positioning groove 121, so as to ensure the stability of the second return compression spring 109 during the expansion and contraction process. Among them, the second return compression spring 109 constitutes a second return elastic member.

[0074] In this embodiment, a braking protrusion 120 is provided on the outer side of the braking block 112, and both sides of the braking protrusion 120 in the axial direction of the upper braking cylinder 106 are inclined surfaces, so that after the braking block 112 hits an obstacle, the braking block 112 is easy to retract, thereby preventing the drainage robot from getting stuck when running in the well. Among them, the inclined surface is a straight inclined surface for easy processing. In other embodiments, the inclined surface can be an arc-shaped inclined surface.

[0075] In this embodiment, a transmission hook 111 is fixed on the inner side of the brake block 112, and the transmission hook 111 is located between the two second compression spring positioning grooves 121. A hook head 119 is provided at one end of the transmission hook 111 away from the brake block 112. The hook head 119 is a cylindrical structure.

[0076] like Figure 4 , Fig. 9 , Fig.10 as well as Fig.11 As shown, a diameter reducing groove is provided at the end of the transmission cylinder 113, the notch of the diameter reducing groove faces the drive motor 102, and the diameter reducing groove has two transmission groove wall sections 128 in the circumferential direction of the transmission cylinder 113, and the transmission groove wall sections 128 gradually approach the center line of the transmission cylinder 113 in the circumferential direction (clockwise direction) of the transmission cylinder 113. Among them, the two transmission groove wall sections 128 are of a central symmetrical structure, and the groove wall surface of the transmission groove wall section 128 constitutes a diameter reducing surface.

[0077] In this embodiment, the transmission hook 11 is in a U-shaped structure as a whole, and the hook head 119 enters the reducing groove from the notch of the reducing groove and is hooked on the transmission groove wall section 128 .

[0078] In this embodiment, the transmission groove wall section 128 includes a first groove wall unit 125 and a second groove wall unit 126 , and the change rate of the first groove wall unit 125 close to the center line of the transmission cylinder 113 is smaller than the change rate of the second groove wall unit 126 close to the center line of the transmission cylinder 113 .

[0079] In this embodiment, the transmission shaft 107 passes through the transmission cylinder 113. Fig.14 As shown, a driving sleeve 63 is provided at the upper end of the transmission shaft 107, and a driving block 64 is provided on the outer circumferential surface of the driving sleeve 63, and the driving block 64 corresponds to the fan-shaped groove 62 one by one; the driving sleeve 63 is inserted into the shaft mounting groove 61, and the driving block 64 is in the fan-shaped groove 62, and the size of the fan-shaped groove 62 in the circumferential direction of the transmission shaft 107 is larger than the size of the driving block 64 in the circumferential direction of the transmission shaft 107, and the driving block 64 is used to drive the inner cylinder 59 to rotate to open and close the flow channel valve 48. Among them, the driving sleeve 63 is a part of the transmission shaft 107. In other embodiments, the driving sleeve and the transmission shaft are integrally formed.

[0080] In this embodiment, the transmission cylinder 113 includes a small diameter section 123 and a large diameter section 124. The transmission groove is arranged on the large diameter section 124. The length of the small diameter section 123 is longer, so that the contact area between the transmission shaft 107 and the transmission cylinder 113 is larger, thereby ensuring the stability of power transmission; moreover, the transmission wheel 113 is longer as a whole, which is conducive to installing the transmission wheel 113 into the upper cylinder 106.

[0081] like Fig.10 As shown, the large diameter section 124 is not a complete cylinder, so that a larger gap is formed in a partial area between the large diameter section 124 and the upper cylinder 106, so that sand or dirt entering the upper cylinder 106 can fall through the gap, avoiding the variable diameter wheel 113 from getting stuck when rotating.

[0082] The working process of the brake system 1003 is as follows: in the up and down operation, when the speed sensor 1004 detects that the current running speed exceeds the set value, the drive motor 102 is controlled to rotate forward through the signal, and the coupling 104 drives the transmission cylinder 113 to rotate forward. Under the action of the second return compression spring 109, the transmission hook 111 moves radially outward along the brake cylinder body, and the hook head 119 corresponds to the position of the second groove wall unit 126 farthest from the center line of the transmission shaft 107. At this time, Figure 5 and Figure 6 As shown, the brake block 112 can be opened to the maximum, so that the brake protrusion 120 and the oil pipe 105 generate friction and the brake protrusion 120 and the coupling gap 110 generate hooking, so as to achieve braking, thereby reducing the running speed of the robot, wherein the hooking of the brake protrusion 120 and the coupling gap 110 is the main braking force; when the speed sensor 1004 detects that the current running speed is lower than the set value, the drive motor 102 is reversed through signal control, the coupling 104 drives the transmission cylinder 113 to rotate in the opposite direction, the second groove wall unit 126, the first groove wall unit 125 and the hook head 119 are pushed and matched in turn to overcome the elastic force of the second return compression spring 109, and then drive the transmission hook 111 to move radially inward along the brake cylinder body. At this time, the hook head 119 is hooked at the set position of the first groove wall unit 125, so that the brake block 112 is contracted to the minimum to avoid friction with the oil pipe 105, and the running speed is increased under the action of the bottom hole pressure.

[0083] like Figure 5 As shown, for low-yield gas wells, when the sensor detects that the lifting pressure is insufficient, the drive motor 102 is controlled to rotate forward through a signal, and the brake block 112 is rebounded to the maximum, so that the brake protrusion 120 of the brake block 112 is stuck in the coupling gap 110 to achieve energy storage; when the speed sensor 1004 detects that the lifting pressure reaches the set value, the drive motor 102 is controlled to reverse through a signal, so that the brake block 112 shrinks to the minimum, so that the drainage robot continues to move upward and avoids falling to the bottom of the well.

[0084] The braking system 1003 of the present invention can adjust the radial movement of the brake block in real time according to the current operating state and well conditions, control the operating speed of the drainage robot, effectively avoid excessive impact force when the drainage robot reaches the extreme position, prevent the drainage robot from being damaged, and increase the service life of the drainage robot. At the same time, it protects the bottom of the well and the wellhead equipment, greatly reducing the safety production accidents caused by high-speed impacts.

[0085] The linkage process between the brake block 112 and the flow channel valve 48 is as follows: when the robot is ready to move downward, the driving motor 102 rotates forward, and drives the brake block 112 to change its diameter from large to small through the transmission shaft 107, and the brake is closed. Due to the action of the fan-shaped groove 62, the inner cylinder 59 will not rotate during the process of the brake block 112 changing from a large diameter to a medium diameter (corresponding to the second thin-walled unit 126) (in this process, the driving block 64 moves from one side of the fan-shaped groove 62 to the other side along the circumference of the transmission shaft 107), and the flow channel valve 48 is in a closed state; during the process of the brake block 112 changing from a medium diameter to a small diameter (corresponding to the first thin-walled unit 125), the inner cylinder 59 rotates with the transmission shaft 107 under the action of the driving block 64, so that the flow channel opening 60 used in conjunction with the outer cylinder and the inner cylinder 59 is connected, and the flow channel valve 48 is opened. When the robot is hovering or braking at the bottom of the well, the driving motor 102 reverses, drives the brake block 112 to change its diameter from small to large through the transmission shaft 107, and turns on the brake. Due to the action of the fan-shaped groove 62, the inner cylinder 59 will not rotate during the process of the brake block 112 changing from a small diameter to a medium diameter (in this process, the driving block 64 moves from one side of the fan-shaped groove 62 to the other side along the circumference of the transmission shaft 107), and the flow channel valve remains open; during the process of the brake block 112 changing from a medium diameter to a large diameter, the inner cylinder 59 rotates with the transmission shaft 107 under the action of the driving block 64, so that the flow channel openings 60 used in conjunction with the outer cylinder and the inner cylinder 59 are staggered, and the flow channel valve 48 is closed. When the robot is ready to go up, the driving motor 102 rotates forward, drives the brake block 112 to change its diameter from large to medium through the transmission shaft 107, and turns off the brake. Due to the action of the fan-shaped groove 62, the inner cylinder 59 will not rotate during the process of the brake block 112 changing from a large diameter to a medium diameter, and the flow channel valve 48 remains closed. The fan-shaped groove 62 plays a transition role in the process of the brake block 112 changing from a large diameter to a small diameter or from a small diameter to a large diameter, thereby realizing discontinuous control of the flow channel valve 48 .

[0086] The working process of the drainage robot is as follows: Figures 15 to 17As shown, the drainage volume is determined by the sensor monitoring data, the descending depth is determined and the robot starts to descend. At this time, the brake system 1003 is closed, the flow channel valve 48 is opened, and the liquid below the sealing end face can quickly pass through the central flow channel to the upper end of the drainage robot, so that the upper and lower pressures of the drainage robot are balanced. At the same time, the rubber tube 45 of the sealing system 1002 is kept at the minimum outer diameter, and no friction is generated with the inner wall of the oil pipe 105, and the drainage robot descends rapidly; when the drainage robot descends to the predetermined depth, the brake system 1003 is opened, so that the brake block 112 is hooked in the coupling gap 110, and the flow channel valve 48 is closed at the same time. The rubber tube 45 expands and changes diameter due to the high pressure downhole, and is close to the oil pipe 105 to achieve full sealing. At this time, the drainage robot is suspended in the downhole for energy storage; when the sensor detects that the upper and lower pressure differences reach the set value, the brake system 1003 is closed through a signal, the flow channel valve 48 remains closed, and the drainage robot pushes the upper liquid column to quickly ascend; when the speed sensor 1004 detects that the current speed of the drainage robot is too fast, the brake system 1003 is opened through a signal command, thereby controlling the working speed of the drainage robot. Its internal sensors constantly monitor the robot's operating status and various parameters in the well, and store them in the internal data storage. After the drainage robot reaches the wellhead, it transmits the stored downhole data and the robot's own operating data to the background control computer through the signal transmission device 1007, and determines the next drainage volume and prepares for the next work cycle. The drainage robot performs drainage work repeatedly in the well until the work goal is completed.

[0087] Embodiment 2 of the drainage robot of the present invention:

[0088] The difference between this embodiment and embodiment 1 lies in the structures of the braking system and the flow channel valve.

[0089] like Fig.18 As shown, the brake system includes a brake cylinder, which is arranged in the oil pipe 15 along the up and down direction, and includes an upper brake cylinder 25, a joint 17 and a lower brake cylinder 12, and the upper brake cylinder 25 and the lower brake cylinder 12 are connected together through the joint 17. Among them, the joint 17 has a transmission shaft through hole.

[0090] In this embodiment, the inner cavity of the lower brake cylinder 12 constitutes a driving chamber 13, and a driving motor 11 is arranged in the driving chamber 13. The driving motor 11 is connected to the transmission shaft 16 through a screw nut mechanism 14 to drive the transmission shaft 16 to move axially along the brake cylinder. The transmission shaft 16 passes through the transmission shaft through-hole and extends into the inner cavity of the upper brake cylinder 25.

[0091] In this embodiment, a transmission cylinder 20 is disposed in the inner cavity of the upper brake cylinder 25 . The transmission cylinder 20 is fixed on the transmission shaft 16 so as to move along the axial direction of the brake cylinder with the transmission shaft 16 .

[0092] like Fig.18and Fig.21 As shown, an upper brake limit sleeve 24 and a lower brake limit sleeve 19 are provided on the upper brake cylinder 25, and an installation groove is formed between the two brake limit sleeves. A brake block 22 is installed in the installation groove. The brake block 22 is arranged outside the upper brake cylinder 25, and two brake blocks 22 are arranged along the circumference of the upper brake cylinder 25.

[0093] In this embodiment, the bottom of the installation groove is provided with an avoidance hole 26, a first compression spring positioning groove 27 and a limiting groove 28; each brake block 22 corresponds to one avoidance hole 26, and the avoidance hole 26 is located in the middle position of the installation groove in the axial direction of the upper brake cylinder 25; each brake block 22 corresponds to two first compression spring positioning grooves 27, and the two first compression spring positioning grooves 27 are located on both sides of the avoidance hole 26 in the axial direction of the upper brake cylinder 25; each brake block 22 corresponds to two limiting grooves 28, and the two limiting grooves 28 are located on both sides of the avoidance hole 26 in the axial direction of the upper brake cylinder 25. Among them, the first compression spring positioning groove 27 is between the avoidance hole 26 and the corresponding limiting groove 28.

[0094] like Fig.18 and Fig. 22 As shown, the brake block 22 is provided with limiting protrusions 32 at both ends of the upper brake cylinder 25 in the axial direction. After the limiting protrusion 32 is inserted into the limiting groove 28, the upper brake limiting sleeve 24 and the lower brake limiting sleeve 19 cooperate to make the brake block 22 float and be assembled on the upper brake cylinder 25.

[0095] In this embodiment, a second compression spring positioning groove 31 is provided on the inner side surface of the brake block 22, and two second compression spring positioning grooves 31 are provided, and the second compression spring positioning grooves 31 are arranged one-to-one with the first compression spring positioning grooves 27; a return compression spring 23 is provided between the brake block 22 and the upper brake cylinder 25, and the return compression spring 23 is used to apply an elastic force to the brake block 22 to make it move away from the upper brake cylinder 25; one end of the return compression spring 23 is installed in the first compression spring positioning groove 27, and the other end of the return compression spring 23 is installed in the second compression spring positioning groove 31, so as to ensure the stability of the return compression spring 23 during the expansion and contraction process. Among them, the return compression spring 23 constitutes a return elastic member.

[0096] In this embodiment, a braking protrusion 30 is provided on the outer side of the brake block 22, and both sides of the braking protrusion 30 in the axial direction of the upper brake cylinder 25 are inclined surfaces, so that after the brake block 22 hits an obstacle, the brake block 22 is easy to retract, thereby preventing the drainage robot from getting stuck when running in the well. Among them, the inclined surface is a straight inclined surface for easy processing. In other embodiments, the inclined surface can be an arc inclined surface.

[0097] In this embodiment, a transmission hook 21 is fixedly disposed on the inner side of the brake block 22, the transmission hook 21 is located between the two second compression spring positioning grooves 31, and a hook head 29 is disposed at one end of the transmission hook 21 away from the brake block 22. The hook head 29 is a conical structure.

[0098] like Fig.18 and Fig.23 As shown, the transmission cylinder 20 has a central hole, which includes a large hole section 36, a tapered hole section 35 and a small hole section 34. The tapered hole section 35 is connected between the large hole section 36 and the small hole section 34. A guide groove 37 is provided on the hole wall of the central hole. The guide groove 37 connects the inside and outside of the transmission cylinder 20, and the guide groove 37 extends along the axial direction of the transmission cylinder 20. Among them, the inner wall surface of the tapered hole section 35 constitutes a variable diameter surface.

[0099] In this embodiment, a hook hole 38 is provided at the upper end of the guide groove 37, and the hook hole 38 is for the hook 29 to pass through, so as to enter the central hole of the transmission cylinder 20 along the radial direction of the transmission cylinder 20, and the hook 29 is hooked on the groove edge of the guide groove 37. The hook hole 38 is a round hole. In other embodiments, the hook hole can be set at the lower end of the guide groove.

[0100] In this embodiment, the transmission cylinder 20 includes a connection seat 33, which is located below the small hole section 34. The transmission cylinder 20 is fixed to the transmission shaft 16 through the connection seat 33. This design facilitates the processing of the center hole. The transmission shaft 16 passes through the center hole (not shown in the figure).

[0101] In this embodiment, the flow channel valve includes an outer cylinder and an inner cylinder, and the transmission shaft 16 drives the inner cylinder to move axially along the transmission shaft in the outer cylinder to open and close the flow channel valve.

[0102] In this embodiment, the transmission cylinder 20 is a cylindrical structure, which is designed so that the hole wall at the small hole section 34 is thicker to ensure the overall strength of the transmission cylinder 20.

[0103] During the up and down operation, when the speed sensor detects that the current running speed exceeds the set value, the drive motor 11 is controlled to rotate forward through the signal, and the screw nut mechanism 14 drives the transmission cylinder 20 to move axially downward. Under the action of the reset compression spring 23, the transmission hook 21 moves radially outward along the brake cylinder body, and the hook head 29 is arranged corresponding to the inner wall of the large hole section 36. At this time, Fig.19 and Fig. 20As shown, the brake block 22 can be opened to the maximum, so that the brake protrusion 30 and the oil pipe 15 produce friction and the brake protrusion 30 and the coupling gap 18 produce hooking, so as to achieve braking, thereby reducing the running speed of the robot, wherein the hooking of the brake protrusion 30 and the coupling gap 18 is the main braking force; when the speed sensor detects that the current running speed is lower than the set value, the drive motor 11 is reversed through signal control, the screw nut mechanism 14 drives the transmission cylinder 20 to move axially upward, and the inner wall surface of the tapered hole section 35 is pushed and matched with the hook head 29 to overcome the elastic force of the reset compression spring 23, thereby driving the transmission hook 21 to move radially inward along the brake cylinder body. At this time, the hook head 29 is arranged corresponding to the inner wall of the small hole section 34 and hooked on the inner wall surface of the transmission cylinder 20, so that the brake block 22 is contracted to the minimum to avoid friction with the oil pipe 15, and the running speed is increased under the action of the bottom hole pressure.

[0104] like Fig.19 As shown, for low-yield gas wells, when the sensor detects that the lifting pressure is insufficient, the drive motor 11 is controlled to rotate forward through a signal, and the brake block 22 is rebounded to the maximum, so that the brake protrusion 30 of the brake block 22 is stuck in the coupling gap 18 to achieve energy storage; when the sensor detects that the lifting pressure reaches the set value, the drive motor 11 is controlled to reverse through a signal, so that the brake block 22 shrinks to the minimum, so that the drainage robot continues to move upward and avoids falling to the bottom of the well.

[0105] Embodiment 3 of the drainage robot of the present invention:

[0106] The difference between this embodiment and embodiment 1 is that in embodiment 1, the transmission groove wall section 128 includes a first groove wall unit 125 and a second groove wall unit 126, and the change rate of the first groove wall unit 125 close to the center line of the transmission cylinder 113 is smaller than the change rate of the second groove wall unit 126 close to the center line of the transmission cylinder 113. In this embodiment, the transmission groove wall section includes only one groove wall unit, and the groove wall unit gradually approaches the center line of the transmission cylinder in the clockwise direction.

[0107] Embodiment 4 of the drainage robot of the present invention:

[0108] The difference between this embodiment and embodiment 1 is that in embodiment 1, after hovering, the two elastic sealing components 54 and the rubber tube 45 work together to seal to achieve energy storage. In this embodiment, no rubber tube and pressure transmission tube are provided, and only two elastic sealing components are used to seal to achieve energy storage.

[0109] Embodiment 5 of the drainage robot of the present invention:

[0110] The difference between this embodiment and embodiment 1 is that in embodiment 1, a pressure transmission tube 51 is provided on the lower sealing cylinder 47, and the lumen of the pressure transmission tube 51 constitutes a pressure transmission channel. In this embodiment, a pressure transmission groove is processed on the lower sealing cylinder, a sealing cover is welded to the notch of the pressure transmission groove, and the groove cavity of the pressure transmission groove constitutes a pressure transmission channel.

[0111] Embodiment 6 of the drainage robot of the present invention:

[0112] The difference between this embodiment and embodiment 1 is that in embodiment 1, two groups of elastic sealing components 54 are provided, and the rubber cylinder 45 is located between the two groups of elastic sealing components 54. In this embodiment, only one group of elastic sealing components is provided, and the rubber cylinder is located above the elastic sealing components.

[0113] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. The patent protection scope of the present invention shall be based on the claims. All equivalent structural changes made using the contents of the description and drawings of the present invention should also be included in the protection scope of the present invention.

Claims

1. A drainage robot, characterized in that: It includes a sealing system (1002) and a braking system (1003); The sealing system (1002) comprises a sealing cylinder and a flow channel valve (48), wherein the sealing cylinder has a central flow channel; an elastic sealing assembly (54) is sleeved on the sealing cylinder, wherein the elastic sealing assembly (54) comprises a first resetting elastic member and a sealing body (50), wherein under the action of the first resetting elastic member, the sealing body (50) is used to press against the inner wall of the oil pipe (105); the flow channel valve (48) comprises an outer cylinder and an inner cylinder (59), wherein the outer cylinder is connected to the lower part of the sealing cylinder, and the inner cylinder (59) can move relative to the outer cylinder to control the opening and closing of the central flow channel; The brake system (1003) comprises a brake cylinder, in which a drive device and a transmission cylinder (113) are arranged, the drive device comprises a drive motor (102) and a transmission shaft (107), the drive motor (102) is connected to the inner cylinder (59) by transmission via the transmission shaft (107); the transmission cylinder (113) is fixed on the transmission shaft (107), and a diameter-changing surface is provided in the cylinder wall of the transmission cylinder (113); a brake block (112) is provided on the outside of the brake cylinder, and the brake block (112) is arranged along the circumference of the brake cylinder There are at least two brake blocks (112), the outer surface of which is provided with a brake convex portion (120), and both side surfaces of the brake convex portion (120) in the axial direction of the brake cylinder are inclined surfaces; the inner side of the brake block (112) is provided with a transmission hook (111), and the transmission hook (111) has a hook head (119), and the hook head (119) is hooked on the diameter-changing surface; a second reset elastic member is provided between the brake cylinder and the corresponding brake block (112), and the second reset elastic member is used to apply an elastic force to the brake block (112) to make it move away from the brake cylinder.

2. The drainage robot according to claim 1, characterized in that: The drive motor (102) drives the transmission shaft (107) to rotate along the circumferential direction of the brake cylinder body, and the inner cylinder (59) rotates relative to the outer cylinder under the drive of the transmission shaft (107); a diameter-changing groove is provided at the end of the transmission cylinder (113), and the diameter-changing groove has at least two transmission groove wall sections (128) in the circumferential direction of the transmission cylinder (113); the transmission groove wall sections (128) gradually approach or move away from the center line of the transmission cylinder (113) in the circumferential direction of the transmission cylinder (113), and the groove wall surface of the transmission groove wall section (128) constitutes the diameter-changing surface.

3. The drainage robot according to claim 2, characterized in that: The transmission groove wall section (128) comprises a first groove wall unit (125) and a second groove wall unit (126), wherein the rate of change of the first groove wall unit (125) approaching or moving away from the center line of the transmission cylinder (113) is smaller than the rate of change of the second groove wall unit (126) approaching or moving away from the center line of the transmission cylinder (113).

4. The drainage robot according to claim 2 or 3, characterized in that: A driving block (64) is convexly provided on the outer circumferential surface of the transmission shaft (107); a shaft mounting groove (61) is provided at the lower portion of the inner cylinder (59); a fan-shaped groove (62) is provided on the groove wall of the shaft mounting groove (61); the shaft mounting groove (61) is adapted to fit the transmission shaft (107); and the driving block (64) moves in the fan-shaped groove (62) along the circumferential direction of the transmission shaft (107).

5. The drainage robot according to claim 4, characterized in that: At least two drive blocks (64) are arranged at intervals along the circumference of the transmission shaft (107), and the fan-shaped grooves (62) correspond to the drive blocks (64) one by one.

6. The drainage robot according to claim 1, 2 or 3, characterized in that: The sealing system (1002) further comprises a rubber sleeve (45), the rubber sleeve (45) being sleeved on the sealing cylinder body, the rubber sleeve (45) and the sealing cylinder body forming an annular cavity (46); a pressure transmission channel is provided on the sealing cylinder body, one end of the pressure transmission channel is in communication with the annular cavity (46), and the other end of the pressure transmission channel is located below the elastic sealing component (54) and in communication with the outside of the sealing cylinder body; a one-way valve (52) is provided on the pressure transmission channel, the one-way valve (52) comprising a valve core (56) and a third reset elastic member, the third reset elastic member being used to apply an elastic force to the valve core (56) to close the pressure transmission channel, and a pressure relief hole (58) is provided on the valve core (56), the pressure relief hole (58) extending through the valve core (56) axially.

7. The drainage robot according to claim 6, characterized in that: The sealing cylinder is provided with a pressure transmission tube (51), and the lumen of the pressure transmission tube (51) constitutes the pressure transmission channel.

8. The drainage robot according to claim 6, characterized in that: The elastic sealing components (54) are provided in two groups, and the rubber cylinder (45) is located between the two groups of elastic sealing components (54).

9. The drainage robot according to claim 1, characterized in that: The driving motor drives the transmission shaft to move axially along the brake cylinder body, and the inner cylinder slides axially relative to the outer cylinder along the transmission shaft under the drive of the transmission shaft; the transmission cylinder has a center hole, the center hole includes a large hole section, a small hole section and a tapered hole section, the tapered hole section is connected between the large hole section and the small hole section, and a guide groove connecting the inside and outside of the transmission cylinder is provided on the hole wall of the center hole, the guide groove extends along the axial direction of the transmission cylinder, and the inner wall surface of the tapered hole section constitutes the variable diameter surface.

10. The drainage robot according to claim 9, characterized in that: At least one end of the guide groove is provided with a hook through hole, and the hook through hole is used for the hook to pass through and enter the central hole of the transmission cylinder.

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