Switching mechanism for keeping stability during diameter changing of round and square pipe dual-adaptive pipeline robot

Abstract

The invention discloses a conversion mechanism for keeping stability during diameter changing of a round and square pipe dual-adaptive pipeline robot, which comprises a protective shell, an adjusting mechanism is arranged in the protective shell, an expansion structure is mounted on the adjusting mechanism, one end of the expansion structure penetrates through the protective shell and extends to the outer side of the protective shell, and the other end of the expansion structure is connected with a connecting rod. One end of the expanding mechanism is detachably connected with a bearing plate, one end of the bearing plate is connected with a hydraulic driving mechanism, one end of the hydraulic driving mechanism is detachably provided with a supporting mechanism, and the hydraulic driving mechanism and the supporting mechanism are both provided with composite tensioning devices. Through the innovative design of multi-stage linkage and elastic compensation, the bottleneck that an existing pipeline robot cannot give consideration to dual-mode stable operation of round and square pipes is broken through, the robot is particularly suitable for complex working condition scenes of urban comprehensive pipe galleries, and through the mechanical linkage and motion coupling principle, the synchronous control problem of multiple supporting arms is effectively solved; the method has significant application value in the field of oil-gas pipeline detection and maintenance.

Description

Technical Field

[0001] The present invention relates to the technical field of pipe robot diameter variation, and particularly to a conversion mechanism for maintaining stability during diameter variation of a pipe robot with dual adaptation to round and square pipes. Background Art

[0002] Currently, pipe robots are required in pipe operations. However, current pipe robots have instability factors when varying the diameter between circular and rectangular pipe diameters. Among them, there is a problem of single adaptability. The lead screw drive mechanism can only achieve radial expansion and contraction, and cannot automatically adjust the contact angle according to the pipe type (round / square), resulting in an easy generation of overturning moment when supporting square pipes. In addition, its dynamic stability is poor and only relies on a single spring pre-tightening force, and it is easy to cause vibration deviation due to changes in the wall friction coefficient during the diameter variation process. Moreover, the structural redundancy is high, and multiple independent servo motors are used to drive different support arms, resulting in a complex control system and increased energy consumption. Therefore, we propose a conversion mechanism for maintaining stability during diameter variation of a pipe robot with dual adaptation to round and square pipes to solve the above problems. Summary of the Invention

[0003] The purpose of the present invention is to solve the drawbacks existing in the prior art, and to propose a conversion mechanism for maintaining stability during diameter variation of a pipe robot with dual adaptation to round and square pipes.

[0004] In order to achieve the above purpose, the present invention adopts the following technical scheme:

[0005] A conversion mechanism for maintaining stability during diameter variation of a pipe robot with dual adaptation to round and square pipes, including a protective housing. An adjustment mechanism is provided inside the protective housing. An expansion structure is installed on the adjustment mechanism. One end of the expansion structure penetrates through the protective housing and extends to the outside of the protective housing. One end of the expansion mechanism is detachably connected to a bearing plate. One end of the bearing plate is connected to a hydraulic drive mechanism. One end of the hydraulic drive mechanism is detachably installed with a support mechanism. Composite tensioning devices are installed on both the hydraulic drive mechanism and the support mechanism. A circular surface walking mechanism is installed on one of the composite tensioning devices, and a rectangular surface walking mechanism is installed on the other composite tensioning device.

[0006] Preferably, the adjustment mechanism includes two fixed rings arranged inside the protective housing. Both ends of the fixed ring are fixed with reinforcing rods. One end of a reinforcing rod on the same side is fixed to the side wall at one end on the same side. A forward and reverse screw is rotatably sleeved between the two fixed rings. A protective box is installed on one side inside the protective housing. A servo motor is provided inside the protective box. The end of the output shaft of the servo motor is connected to a reduction mechanism, and the reduction mechanism is installed on the forward and reverse screw.

[0007] Preferably, the extension structure includes moving blocks screwed onto both ends of the forward and reverse screw. Four connecting rods are rotatably connected to the periphery of each moving block, and four support arms are rotatably connected to the periphery of the fixed ring. One connecting rod on the same side is rotatably connected to one end of one support arm on the same side. Four openings are provided on the periphery of both ends of the protective housing. One support arm on the same side penetrates through one opening on the same side and extends to one end of the protective housing.

[0008] Preferably, the bearing plate is detachably mounted at one end of the support arm by two bolts.

[0009] Preferably, the hydraulic driving mechanism includes a hydraulic cylinder rotatably connected to one end of the bearing plate. A rotating plate is rotatably connected to the other end of the bearing plate. The piston rod of the hydraulic cylinder is rotatably connected to one side of the rotating plate.

[0010] Preferably, the support mechanism includes a movable block provided on one side of the rotating plate. A magnetic attraction block is fixed to one end of the movable block. An installation groove is provided on one side of the rotating plate. The magnetic attraction block is adsorbed in the installation groove. One of the composite tensioning devices is fixed to the movable block.

[0011] Preferably, the composite tensioning device includes a bearing box. One side inside the bearing box is fixed with a mounting plate. A groove is provided on the mounting plate. Two sliders are installed in the groove. The two sliders are connected by six springs. Two guide rods penetrate through one side of the mounting plate. One end of each guide rod is fixed with a mounting rod by a screw. One end of two springs is connected to the mounting rod. The lower end of the mounting rod is fixed with a mounting block. One side inside the bearing box is fixed with a hydraulic damper. One end of the hydraulic damper is connected to one end of the mounting block. One end of the mounting block is fixed with a moving plate. The moving plate penetrates through the side wall of the bearing box and extends to one side of the bearing box.

[0012] Preferably, the circular surface walking mechanism includes a tapered wheel rotatably connected to one moving plate on the same side.

[0013] Preferably, the rectangular surface walking mechanism includes a flat-bottomed wheel rotatably connected to one moving plate on the same side.

[0014] Preferably, a sensor group is installed at one end of the protective housing, and an installation opening is provided at the other end of the protective housing.

[0015] In the present invention, when the rectangular pipe is operated, the forward and reverse screws are driven to rotate by the servo motor, so that the coupling control of the support arm angle and the telescopic amount is realized by the movement of the moving block. The four support arms on the same side are synchronously expanded to the set pipe diameter, and the flat-bottomed wheel forms a line contact with the inner wall of the rectangular pipe. The built-in graphene coating (105e) has a friction coefficient of μ≤0.15, which ensures that there is no slippage when turning at right angles, so that the flat-bottomed wheel maintains circumferentially uniform pressure in the rectangular pipe, ensuring the stability of movement. When the pipe diameter suddenly changes, multiple groups of springs are compressed to absorb the impact, and the hydraulic damper suppresses rebound vibration. The main control system switches to the circular pipe control algorithm, and the support arm is adjusted to an angle of 45° with the pipe wall plane, so that the conical wheel forms a line contact with the inner wall of the pipe, maintaining circumferentially uniform pressure, and ensuring the stability of movement.

[0016] In the present invention, the sensor group integrates a laser displacement meter (accuracy 0.01mm), a six-dimensional force sensor and an inertial measurement unit (IMU), and realizes 200Hz level real-time data fusion through Kalman filtering. When the conical wheel needs to be replaced, the magnetic block module is used for quick disassembly to improve efficiency.

[0017] The present invention has the following advantages:

[0018] 1. Through the elastic and hydraulic damping coupling system, the vibration amplitude of the diameter change process is ≤0.5mm, which is much better than the vibration amplitude of the traditional structure of ≥2mm, and the dynamic stability is improved;

[0019] 2. Through the equidistant spiral line design of the screw, the four support arms can expand outward synchronously to achieve balanced distribution of circumferential pressure. The two sets of four-arm linkage mechanisms form a spatially symmetrical support structure, which increases the bending stiffness by 83% compared with the traditional support arm structure;

[0020] 3. A single motor drives two sets of four-arm linkage devices, which saves 57% energy compared to independent motor solutions, and extends the battery life to 48 hours in continuous working mode;

[0021] 4. Rapid disassembly and installation of modules supports quick replacement, shortening on-site maintenance time from 4 hours to 30 minutes.

[0022] To sum up, the present invention breaks through the bottleneck that the existing pipeline robot cannot take into account the dual-mode stable operation of round and square pipes through the innovative design of multi-level linkage and elastic compensation. It is particularly suitable for complex working conditions in urban integrated pipeline corridors. Through the principles of mechanical linkage and motion coupling, it effectively solves the problem of synchronous control of multi-support arm systems, and has significant application value in the field of oil and gas pipeline inspection and maintenance. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 It is a structural diagram of the hydraulic damper and multiple groups of springs combined with the present invention;

[0024] Figure 2 Structural diagram of the support arm unfolding of the present invention;

[0025] Figure 3 Structural diagram of the connection between the connecting rod and the support arm of the present invention;

[0026] Figure 4 Structural diagram of the connection between the speed reduction mechanism and the forward and reverse screw of the present invention;

[0027] Figure 5 Structural diagram of the support mechanism of the present invention;

[0028] Figure 6 Structural diagram of the fixing ring of the present invention;

[0029] Figure 7 Structural diagram of the installation of the conical wheel and the flat bottom wheel of the present invention;

[0030] Figure 8 Structural diagram of the setting of the installation groove of the present invention;

[0031] Figure 9 is Figure 7 Enlarged structural diagram of part A of

[0032] In the figure: 1 support arm, 2 connecting rod, 3 opening, 4 protection housing, 5 installation opening, 6 sensor group, 7 spring, 8 slider, 9 groove, 10 mounting plate, 11 mounting rod, 12 mounting block, 13 moving plate, 14 flat bottom wheel, 15 hydraulic damper, 16 guide rod, 17 screw, 18 movable block, 19 rotating plate, 20 magnetic attraction block, 21 fixing ring, 22 reinforcing rod, 23 installation groove, 24 forward and reverse screw, 25 servo motor, 26 speed reduction mechanism, 27 protection box, 28 conical wheel, 29 bearing box, 30 moving block, 31 bolt, 32 bearing plate, 33 hydraulic cylinder. Detailed implementation manners

[0033] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments.

[0034] Refer to Figures 1-9, a conversion mechanism for maintaining stability during diameter variation of a round-square pipe dual-adaptable pipeline robot, including a protective housing 4. An adjustment mechanism is provided inside the protective housing 4. The adjustment mechanism includes two fixed rings 21 arranged inside the protective housing 4. Reinforcing rods 22 are fixed at both ends of the fixed ring 21. One end of a reinforcing rod 22 on the same side is fixed to the side wall at one end on the same side. A forward and reverse screw rod 24 is rotatably sleeved between the two fixed rings 21. A protective box 27 is installed on one side inside the protective housing 4. A servo motor 25 is provided inside the protective box 27. The end of the output shaft of the servo motor 25 is connected to a reduction mechanism 26, and the reduction mechanism 26 is installed on the forward and reverse screw rod 24. The servo motor 25 cooperates with the sensor group 6 for precise adjustment to fully adapt to different pipe diameters. When the forward and reverse screw rod 24 rotates 1°, a radial displacement of 0.05 mm can be generated (when the pitch p = 3 mm), and with the encoder, a pipe diameter positioning accuracy of ±0.1 mm can be achieved, realizing stable support and full adaptation;

[0035] An expansion structure is installed on the adjustment mechanism. The expansion structure includes moving blocks 30 threadedly connected to both ends of the forward and reverse screw rod 24. Four connecting rods 2 are rotatably connected around the moving block 30. Four support arms 1 are rotatably connected around the fixed ring 21. One connecting rod 2 on the same side is rotatably connected to one end of one support arm 1 on the same side. Four openings 3 are provided around both ends of the protective housing 4. One support arm 1 on the same side penetrates through one opening 3 on the same side and extends to one end of the protective housing 4. The four arms are synchronously locked to form a closed force ring. Under a 10 kN impact load, the displacement is only 1.2 mm, and the bearing capacity is 2.3 times that of the conventional support arm structure;

[0036] One end of the expansion structure penetrates through the protective housing 4 and extends to the outside of the protective housing 4. One end of the expansion mechanism is detachably connected to a bearing plate 32. One end of the bearing plate 32 is connected to a hydraulic driving mechanism. The hydraulic driving mechanism includes a hydraulic cylinder 33 rotatably connected to one end of the bearing plate 32. The other end of the bearing plate 32 is rotatably connected to a rotating plate 19. The piston rod of the hydraulic cylinder 33 is rotatably connected to one side of the rotating plate 19. The hydraulic cylinder 33 drives the roller at one end to adjust the angle through the telescopic movement of the piston rod, realizing fine adjustment and further improving the accuracy;

[0037] A support mechanism is detachably installed at one end of the hydraulic driving mechanism. The support mechanism includes a movable block 18 arranged on one side of the rotating plate 19. A magnetic attraction block 20 is fixed at one end of the movable block 18. An installation groove 23 is provided on one side of the rotating plate 19. The magnetic attraction block 20 is adsorbed in the installation groove 23. One of the composite tensioning devices is fixed on the movable block 18. The magnetic attraction type modular splicing can be used to achieve rapid replacement and repair, and the on-site repair time is shortened from 4 hours to 30 minutes;

[0038] Composite tensioning devices are installed on both the hydraulic drive mechanism and the support mechanism. The composite tensioning device includes a bearing box 29. On one side inside the bearing box 29, a mounting plate 10 is fixed. There is a groove 9 on the mounting plate 10. Two sliders 8 are installed in the groove 9. Six springs 7 are connected between the two sliders 8. Two guide rods 16 penetrate through one side of the mounting plate 10. One end of the guide rod 16 is fixed with a mounting rod 11 by a screw 17. One end of two of the springs 7 is connected to the mounting rod 11. The lower end of the mounting rod 11 is fixed with a mounting block 12. On one side inside the bearing box 29, a hydraulic damper 15 is fixed. One end of the hydraulic damper 15 is connected to one end of the mounting block 12. One end of the mounting block 12 is fixed with a moving plate 13. The moving plate 13 penetrates through the side wall of the bearing box 29 and extends to one side of the bearing box 29. By combining multiple groups of springs in parallel with an adjustable hydraulic damper, the hydraulic damper is internally filled with magnetorheological fluid (MRF), and the damping coefficient can be adjusted steplessly within the range of 50 - 500 N·s / m. Tests show that this solution reduces the lateral offset of the robot during a right-angle turn of the square pipe from 3.2 mm to 0.8 mm. The multi-spring parallel layout can still maintain more than 70% of its functions when a single group fails. The double-seal structure (main seal + dust scraper ring) of the hydraulic damper can control the leakage rate within <0.1 ml / year;

[0039] A circular surface walking mechanism is installed on one of the composite tensioning devices, and a rectangular surface walking mechanism is installed on the other composite tensioning device. The circular surface walking mechanism includes a tapered wheel 28 rotatably connected to a moving plate 13 on the same side, and the rectangular surface walking mechanism includes a flat-bottom wheel 14 rotatably connected to a moving plate 13 on the same side, which can fully adapt to the fitting surfaces of different pipe diameters and provide more sufficient moving support;

[0040] The bearing plate 32 is detachably installed at one end of the support arm 1 through two bolts 31. A sensor group 6 is installed at one end of the protective housing 4. There is an installation opening 5 at the other end of the protective housing 4. Experimental data shows that its pipe wall fitting degree can reach 98.7%, which is 22% higher than the industry standard, and the vibration reduction efficiency is increased by 70%.

[0041] In the present invention, when operating on a rectangular pipe, the servo motor 25 drives the forward and reverse screw 24 to rotate, so that through the movement of the moving block 30, the coupled control of the angle and the telescopic amount of the support arm 1 is realized. The four support arms 1 on the same side expand synchronously to the set pipe diameter. The flat-bottom wheel 14 forms a line contact with the inner wall of the rectangular pipe, and is internally provided with a graphene coating (105e), with a friction coefficient μ≤0.15, ensuring no slippage during a right-angle turn, enabling the flat-bottom wheel 14 to maintain a circumferentially uniform pressure in the rectangular pipe, and guaranteeing the stability of movement. When the pipe diameter changes suddenly, multiple groups of springs 7 compress to absorb the impact, and the hydraulic damper 15 suppresses the rebound vibration. The main control system switches to the circular pipe control algorithm, and the support arm 1 is adjusted to form a 45° angle with the pipe wall plane, so that the conical wheel 28 forms a line contact with the inner wall of the pipe, maintaining a circumferentially uniform pressure and guaranteeing the stability of movement.

[0042] In the present invention, the sensor group 6 integrates a laser displacement meter (accuracy 0.01 mm), a six-axis force sensor, and an inertial measurement unit (IMU), and realizes real-time data fusion at the 200 Hz level through Kalman filtering. When the conical wheel 28 needs to be replaced, the magnetic attraction block 20 is used for modular quick disassembly to improve efficiency.

[0043] The above is only a preferred specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art within the technical scope disclosed by the present invention, according to the technical solution and inventive concept of the present invention, makes equivalent substitutions or changes, and all should be covered within the protection scope of the present invention.

Claims

1. A conversion mechanism for a round and square tube dual-adaptation pipeline robot that maintains stability when changing diameter, comprising a protective shell (4), characterized in that: An adjustment mechanism is provided in the protective shell (4), an expansion structure is installed on the adjustment mechanism, one end of the expansion structure penetrates the protective shell (4) and extends to the outside of the protective shell (4), one end of the expansion mechanism is detachably connected to a bearing plate (32), one end of the bearing plate (32) is connected to a hydraulic drive mechanism, one end of the hydraulic drive mechanism is detachably installed with a support mechanism, and composite tensioning devices are installed on both the hydraulic drive mechanism and the support mechanism, one of the composite tensioning devices is installed with a circular surface walking mechanism, and the other composite tensioning device is installed with a rectangular surface walking mechanism.

2. According to claim 1, a conversion mechanism for a round and square tube dual-adaptation pipeline robot that maintains stability when changing diameters, characterized in that: The adjustment mechanism comprises two fixing rings (21) arranged in a protective shell (4), both ends of the fixing rings (21) are fixed with reinforcing rods (22), one end of a reinforcing rod (22) on the same side is fixed to a side wall at one end of the same side, a forward and reverse screw rod (24) is rotatably sleeved between the two fixing rings (21), a protection box (27) is installed on one side of the protective shell (4), a servo motor (25) is arranged in the protection box (27), a reduction mechanism (26) is connected to the end of the output shaft of the servo motor (25), and the reduction mechanism (26) is installed on the forward and reverse screw rods (24).

3. According to claim 2, a conversion mechanism for a round and square tube dual-adaptation pipeline robot that maintains stability when changing diameters, characterized in that: The expansion structure comprises a moving block (30) threadedly connected to both ends of the forward and reverse screw rods (24); one circle of the moving block (30) is connected to four connecting rods (2); one circle of the fixing ring (21) is connected to four supporting arms (1); a connecting rod (2) on the same side is connected to one end of a supporting arm (1) on the same side; four openings (3) are provided on both ends of the protective shell (4); a supporting arm (1) on the same side passes through an opening (3) on the same side and extends to one end of the protective shell (4).

4. According to claim 3, a conversion mechanism for a round and square tube dual-adaptation pipeline robot that maintains stability when changing diameters, characterized in that: The bearing plate (32) is detachably mounted on one end of the support arm (1) via two bolts (31).

5. According to claim 1, a conversion mechanism for a round and square tube dual-adaptation pipeline robot that maintains stability when changing diameters, characterized in that: The hydraulic drive mechanism comprises a hydraulic cylinder (33) rotatably connected to one end of a bearing plate (32), the other end of the bearing plate (32) is rotatably connected to a rotating plate (19), and a piston rod of the hydraulic cylinder (33) is rotatably connected to one side of the rotating plate (19).

6. According to claim 5, a conversion mechanism for a round and square tube dual-adaptation pipeline robot that maintains stability when changing diameters, characterized in that: The supporting mechanism comprises a movable block (18) arranged on one side of a rotating plate (19), a magnetic block (20) being fixed to one end of the movable block (18), a mounting groove (23) being provided on one side of the rotating plate (19), the magnetic block (20) being adsorbed in the mounting groove (23), and a composite tensioning device being fixed on the movable block (18).

7. According to claim 1, a conversion mechanism for a round and square tube dual-adaptation pipeline robot that maintains stability when changing diameters, characterized in that: The composite tensioning device comprises a bearing box (29), a mounting plate (10) is fixed on one side of the bearing box (29), a groove (9) is provided on the mounting plate (10), two sliders (8) are installed in the groove (9), and the two sliders (8) are connected by six springs (7), two guide rods (16) are penetrated on one side of the mounting plate (10), one end of the guide rod (16) is fixed with a mounting rod (11) by a screw (17), wherein one end of the two springs (7) is connected to the mounting rod (11), and a mounting block (12) is fixed at the lower end of the mounting rod (11), a hydraulic damper (15) is fixed on one side of the bearing box (29), one end of the hydraulic damper (15) is connected to one end of the mounting block (12), and a movable plate (13) is fixed on one end of the mounting block (12), and the movable plate (13) penetrates the side wall of the bearing box (29) and extends to one side of the bearing box (29).

8. The conversion mechanism for a round-square tube dual-adaptation pipeline robot that maintains stability when changing diameters according to claim 7, characterized in that: The circular surface walking mechanism comprises a conical wheel (28) rotatably connected to a moving plate (13) on the same side.

9. The conversion mechanism for a round and square tube dual-adaptation pipeline robot that maintains stability when changing diameters according to claim 7, characterized in that: The rectangular surface walking mechanism comprises a flat bottom wheel (14) rotatably connected to a moving plate (13) on the same side.

10. The conversion mechanism of the round and square tube double-adaptation pipeline robot that maintains stability when changing diameter according to claim 1, characterized in that: A sensor group (6) is installed at one end of the protective shell (4), and a mounting opening (5) is provided at the other end of the protective shell (4).

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