CN116293194B

CN116293194B - Pipeline robot running gear

Info

Publication number: CN116293194B
Application number: CN202310202260.6A
Authority: CN
Inventors: 刘锋; 黄超雄; 黄嘉锐; 杨文杰; 黄春龙; 卢伟雄
Original assignee: Shaoguan University
Current assignee: Shaoguan University
Priority date: 2023-03-03
Filing date: 2023-03-03
Publication date: 2023-09-22
Anticipated expiration: 2043-03-03
Also published as: CN116293194A

Abstract

The invention relates to a pipeline robot walking device, which comprises a front seat assembly and a rear seat assembly which are oppositely arranged along the same axial direction; the front seat assembly and the rear seat assembly are connected through a first connecting rod structure so as to realize axial relative telescopic movement between the front seat assembly and the rear seat assembly; the front seat assembly is radially provided with a second connecting rod structure along a pipeline, the rear seat assembly is radially provided with a third connecting rod structure along the pipeline, and the second connecting rod structure and the third connecting rod structure alternately act so as to realize the alternate shrinkage and support of the front seat assembly and the rear seat assembly along the pipeline. The pipeline robot running gear realizes the movement of the whole running gear through the cooperation linkage among the first connecting rod mechanism, the second connecting rod mechanism and the third connecting rod mechanism, simplifies the telescopic and driving control modes, and can realize the movement and expansion locking of the robot simultaneously only by driving a single signal source.

Description

Pipeline robot running gear

Technical Field

The invention relates to the technical field of robots, in particular to a pipeline robot walking device.

Background

The pipeline plays an important role in various aspects such as petroleum, natural gas, chemical raw materials, municipal water supply and drainage engineering and the like. Various problems such as corrosion, cracks, siltation and the like can occur along with the increase of the service time of the on-line operation pipeline, and the normal use of the pipeline can be seriously influenced. In order to increase the efficiency of use of the pipeline and extend the life of the pipeline, periodic inspection or other operations of the pipeline are required to be performed on-line. The detection device cannot enter the pipeline, and in the prior art, the detection device enters the pipeline through a robot most commonly, and various nondestructive detection methods are used for detecting the pipeline. Pipeline robots, which are intelligent carriers that move within a pipeline, can often carry various inspection equipment or work tools. In recent years, with the continuous and deep research, the development of pipeline robots enters a brand-new stage, and is mainly applied to the fields of petroleum, chemical industry, natural gas, nuclear industry and the like to finish the work of detecting flaw detection, cleaning and maintaining pipelines.

At present, the pipeline robot has a complex structure and needs a specific transmission mechanism, for example, wheels or caterpillar tracks are adopted as driving components, so that the robot body is large; the peristaltic mechanism needs three telescopic units, peristaltic is realized in the process of alternately telescopic each peristaltic unit, and peristaltic efficiency is low because the peristaltic mechanism can only advance for a certain distance in one period; pipeline robots mostly need complex control systems to control the expansion and the expansion locking of the robots.

Disclosure of Invention

Based on the defects and shortcomings of the prior art are overcome, and the walking device of the pipeline robot is provided.

The invention provides a pipeline robot walking device, comprising:

a front seat assembly and a rear seat assembly which are oppositely arranged along the same axial direction; the front seat assembly comprises a front shell, a front supporting piece and a front driver unit, wherein the front supporting piece is arranged on two opposite sides of the front shell in a radial movement mode, and the front driver unit is arranged on the front shell; the rear seat assembly comprises a rear shell, a rear supporting piece and a rear driver unit, wherein the rear supporting piece is arranged on two opposite sides of the rear shell in a radial movement mode, and the rear driver unit is arranged on the rear shell;

the front driver unit and the rear driver unit are connected through a first connecting rod mechanism so as to realize axial relative telescopic movement between the front seat assembly and the rear seat assembly; the front seat assembly is provided with a second link mechanism driven by the front driver unit, and the two front supporting pieces are connected through the second link mechanism; the rear seat assembly is provided with a third link mechanism driven by the rear driver unit, and the two rear supporting pieces are connected through the third link mechanism; the second link mechanism and the third link mechanism alternately act to achieve alternate contraction and expansion of the front support and the rear support in the radial direction.

Further, the front driver unit comprises a front cam, a front rotating shaft and a front driving motor, wherein the front rotating shaft and the front driving motor are fixed on the front shell, the output end of the front driving motor is fixedly connected with the front rotating shaft through a gear set, and the front cam is fixed on the front rotating shaft; one of the front supporting pieces is provided with an abutting part which abuts against the wheel surface of the front cam, and two ends of the second connecting rod mechanism are respectively arranged on the two front supporting pieces so that the two front supporting pieces can stretch or expand at the same time.

Further, the rear driver unit comprises a rear cam, a rear rotating shaft and a rear driving motor, wherein the rear rotating shaft and the rear driving motor are fixed on the rear shell, the output end of the rear driving motor is fixedly connected with the rear rotating shaft through a gear set, the rear cam is fixed on the rear rotating shaft, and the front cam and the rear cam are arranged in the same plane in a central symmetry manner; one of the rear supporting pieces is provided with an abutting part abutting against the wheel surface of the rear cam, the rear supporting piece in contact with the rear cam and the front supporting piece in contact with the front cam are positioned on the same side, and two ends of the third connecting rod mechanism are respectively arranged on the two rear supporting pieces so that the two rear supporting pieces can stretch or expand simultaneously.

Further, the first link mechanism comprises a first short rod and a first long rod, one end of the first short rod is fixedly connected with the rear rotating shaft, the other end of the first short rod is rotatably connected with one end of the first long rod, and the other end of the first long rod is rotatably connected with the front rotating shaft.

Further, the second link mechanism comprises a second long rod and two groups of second short rods, one ends of the two groups of second short rods are respectively and rotatably connected with the corresponding front supporting piece, the other ends of the two groups of second short rods are correspondingly and rotatably connected with two ends of the second long rod, and the middle point of the second long rod is rotatably connected with the front rotating shaft.

Further, the third link mechanism comprises an inner ring, an outer ring and two groups of third short rods, the inner ring is fixed on the side face of the rear shell, the outer ring is sleeved on the inner ring in a relatively rotatable mode, one ends of the two groups of third short rods are respectively connected with the corresponding rear supporting piece in a rotating mode, and the other ends of the two groups of third short rods are correspondingly connected with two opposite sides of the outer ring in a rotating mode.

Further, the novel rotary shaft is characterized by further comprising a fourth connecting rod mechanism, wherein the fourth connecting rod mechanism comprises a fourth short rod and a fourth long rod, one end of the fourth short rod is fixedly connected with the front rotary shaft, the other end of the fourth short rod is rotatably connected with one end of the fourth long rod, and the other end of the fourth long rod is rotatably connected with the rear rotary shaft.

Further, the first linkage, the second linkage and the third linkage are two groups in number and are correspondingly arranged on the left side and the right side of the front seat assembly and the rear seat assembly.

Further, the front support piece and the rear support piece with the abutting parts further comprise support parts and springs, two ends of each spring are fixedly connected with the corresponding support parts and the corresponding abutting parts respectively, and the support parts are used for abutting against pipe walls of the pipelines.

Further, the connecting assembly comprises a connecting clamping seat and a connecting installation seat, the connecting installation seat is fixedly connected with the rear seat assembly, and an annular clamping groove is formed in one side, far away from the rear seat assembly, of the connecting installation seat along the circumferential direction of the pipeline;

the connecting clamping seat is provided with a rotary shifting piece, a connecting short rod and a fork-shaped connecting rod, the rotary shifting piece is rotatably sleeved on the connecting clamping seat, one end of the connecting short rod is rotatably connected with the rotary shifting piece, the other end of the connecting short rod is rotatably connected with one end of the fork-shaped connecting rod, the other end of the fork-shaped connecting rod is connected with the inner wall of the connecting clamping seat through a torsion spring, and the fork-shaped connecting rod is provided with a pressing part for pressing the bottom of the annular clamping groove.

Compared with the prior art, the walking device of the pipeline robot has the following beneficial effects:

1. according to the pipeline robot walking device, the first connecting rod mechanism, the second connecting rod mechanism and the third connecting rod mechanism are matched and linked, so that the front supporting piece and the rear supporting piece alternately support the pipeline wall in a pressing mode, the movement of the whole walking device is realized, the expansion and the driving control modes are simplified, and the movement, the expansion and the locking of the robot can be realized simultaneously only by driving a single signal source.

2. According to the pipeline robot walking device, the springs are arranged in the supporting pieces, and when the springs shrink, larger supporting force is provided for the supporting parts, so that the pipeline robot walking device is prevented from toppling.

3. According to the pipeline robot walking device, the connecting assembly is arranged on the rear seat assembly, and the connecting assembly realizes rapid installation of the detection part on the pipeline robot walking device through the rapid disassembly structure, so that the installation procedure is simplified, and the working efficiency is improved.

Drawings

FIG. 1 is a schematic view of a pipe robot walking device according to an embodiment of the present invention;

FIG. 2 is an exploded view of the structure of FIG. 1;

FIG. 3 is a schematic view of the front support of FIG. 1;

FIG. 4 is a schematic view of a connection assembly according to an embodiment of the present invention;

FIG. 5 is a partial schematic view of the structure of FIG. 4;

FIG. 6 is a partial schematic view of the structure of FIG. 4;

in the figure: 10. a rear seat assembly; 11. a rear housing; 12. a rear support; 13. a rear drive motor; 14. a rear cam; 15. a rear rotating shaft; 20. a front seat assembly; 21. a front housing; 22. a front support; 221. an abutting portion; 222. a spring; 223. a support part; 23. a front drive motor; 24. a front cam; 25. a front rotating shaft; 30. a first link mechanism; 31. a first stub; 32. a first long rod; 40. a second link mechanism; 41. a second long rod; 42. a second short bar; 50. a third link mechanism; 51. an inner ring; 52. an outer ring; 53. a third short bar; 60. a fourth link mechanism; 61. a fourth short bar; 62. a fourth long rod; 71. connecting the mounting seat; 711. an annular clamping groove; 72. the connecting clamping seat; 721. the pulling piece is rotated; 722. connecting short rods; 723. a fork-shaped connecting rod; 7231. and a pressing part.

Detailed Description

The following are specific embodiments of the present invention and the technical solutions of the present invention will be further described with reference to the accompanying drawings, but the present invention is not limited to these embodiments.

In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, are merely for convenience in describing the present invention and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a specific orientation, be configured and operated in a specific orientation, and thus should not be construed as limiting the present invention.

It will be understood that when an element is referred to as being "fixed to" another element, it can be directly on the other element or intervening elements may also be present. When an element is referred to as being "connected" to another element, it can be directly connected to the other element or intervening elements may also be present.

Aiming at the technical problems of low movement efficiency and the structural structure of a general pipeline robot in the background art, an embodiment of the invention provides a pipeline robot walking device, as shown in fig. 1 and 2, in one embodiment, the pipeline robot walking device comprises a front seat assembly 20 and a rear seat assembly 10 which are oppositely arranged along the same axial direction in a pipeline; the front seat assembly 20 includes a front housing 21, front supports 22 radially movably disposed on opposite sides of the front housing 21, and front driver units disposed on the front housing 21 for driving the front supports 22; the rear seat assembly 10 includes a rear housing 11, rear supports 12 disposed on opposite sides of the rear housing 11 in a radially movable manner, and rear driver units disposed on the rear housing 11 for driving the rear supports 12.

The front and rear driver units are connected by a first linkage 30 to effect an axial relative telescopic movement between the front and rear seat assemblies 20, 10; the front seat assembly 20 is provided with a second link mechanism 40 driven by the front driver unit, the two front supports 22 are connected by the second link mechanism 40, the rear seat assembly 10 is provided with a third link mechanism 50 driven by the rear driver unit, the two rear supports 12 are connected by the third link mechanism 50, and the second link mechanism 40 and the third link mechanism 50 alternately act to achieve the alternate contraction and expansion of the front supports 22 and the rear supports 12 in the radial direction. During operation, the first link mechanism 30, the second link mechanism 40 and the third link mechanism 50 are cooperatively linked, so that the front support member 22 and the rear support member 12 alternately support the pipe wall in a pressing manner, and the movement of the whole walking device is realized.

In one embodiment, as shown in fig. 1 and 2, the front driver unit includes a front cam 24, a front rotating shaft 25, and a front driving motor 23, the front rotating shaft 25 and the front driving motor 23 are fixed on the front housing 21, an output end of the front driving motor 23 is fixedly connected with the front rotating shaft 25 through a gear set, and the front cam 24 is fixed on the front rotating shaft 25. One of the front supporting pieces 22 is provided with an abutting part 221 abutting against the wheel surface of the front cam 24, two ends of the second link mechanism 40 are respectively arranged on the two front supporting pieces 22, and when the front driving motor 23 drives the front cam 24 to rotate, the front supporting pieces 22 are driven by the connection of the second link mechanism 40 so as to enable the two front supporting pieces 22 to stretch or expand simultaneously and support the pipe wall of the pipeline.

Further, the rear driver unit includes a rear cam 14, a rear rotating shaft 15 and a rear driving motor 13, the rear rotating shaft 15 and the rear driving motor 13 are fixed on the rear housing 11, an output end of the rear driving motor 13 is fixedly connected with the rear rotating shaft 15 through a gear set, the rear cam 14 is fixed on the rear rotating shaft 15, and the front cam 24 and the rear cam 14 are arranged in the same plane in a central symmetry manner. One of the rear supports 12 has an abutment 221 abutting against the tread of the rear cam 14, and the rear support 12 contacting the rear cam 14 and the front support 22 contacting the front cam 24 are located on the same side, and both ends of the third link mechanism 50 are respectively disposed on the two rear supports 12, so that when the rear driving motor 13 drives the rear cam 14 to rotate, the rear supports 12 are simultaneously expanded or contracted by the connection of the third link mechanism 50. And because the front cam 24 and the rear cam 14 are disposed in the same plane with central symmetry, when the front support 22 is in the expanded state, the rear support 12 is in the contracted state to achieve alternate contraction and expansion of the front support 22 and the rear support 12 in the radial direction.

In one embodiment, as shown in fig. 1 and 2, the first link mechanism 30 includes a first short lever 31 and a first long lever 32, one end of the first short lever 31 is fixedly connected with the rear rotation shaft 15, the other end of the first short lever 31 is rotatably connected with one end of the first long lever 32, and the other end of the first long lever 32 is rotatably connected with the front rotation shaft 25. In the working process, the rear rotating shaft 15 rotates to drive the first short rod 31 to rotate, so as to drive the first long rod 32 to do reciprocating motion, and realize relative telescopic displacement motion between the front seat assembly 20 and the rear seat assembly 10 along the axial direction.

Preferably, the second link mechanism 40 includes a second long rod 41 and two sets of second short rods 42, one ends of the two sets of second short rods 42 are respectively rotatably connected with the corresponding front supporting members 22, the other ends of the two sets of second short rods 42 are respectively rotatably connected with two ends of the second long rod 41, and the middle point of the second long rod 41 is rotatably connected with the front rotating shaft 25. When the front support 22 on one side moves, the second long rod 41 and the two groups of second short rods 42 correspondingly rotate, so that the front support 22 on the other side is driven to move, and the two front supports 22 are simultaneously telescopic or expanded.

More preferably, the third link mechanism 50 includes an inner ring 51, an outer ring 52, and two sets of third short rods 53, the inner ring 51 is fixed on the side surface of the rear housing 11, the outer ring 52 is rotatably sleeved on the inner ring 51, one ends of the two sets of third short rods 53 are rotatably connected with the corresponding rear supporting members 12, and the other ends of the two sets of third short rods 53 are rotatably connected with two opposite sides of the outer ring 52. When the rear supporting member 12 on one side moves, the outer ring 52 and the two groups of third short rods 53 correspondingly rotate, so that the rear supporting member 12 on the other side is driven to move, and the two rear supporting members 12 are simultaneously telescopic or expanded. Since the third link mechanism 50 and the first link mechanism 30 are on the same plane, the conventional link structure is easy to interfere when the first short rod 31 rotates, so in this embodiment, the third link mechanism 50 adopts the inner ring 51 and the outer ring 52 to cooperate with each other, and the first short rod 31 moves in the inner ring 51, thereby eliminating the risk of interference.

Further, the walking device of the pipeline robot further comprises a fourth link mechanism 60, the fourth link mechanism 60 comprises a fourth short rod 61 and a fourth long rod 62, one end of the fourth short rod 61 is fixedly connected with the front rotating shaft 25, the other end of the fourth short rod 61 is rotatably connected with one end of the fourth long rod 62, and the other end of the fourth long rod 62 is rotatably connected with the rear rotating shaft 15 so as to assist in driving relative telescopic displacement movement between the front seat assembly 20 and the rear seat assembly 10 along the axial direction.

In one embodiment, as shown in fig. 1 and 2, the first, second and third link mechanisms 30, 40 and 50 are two in number and are correspondingly disposed at both left and right sides of the front and rear seat assemblies 20 and 10 to improve the movement efficiency of the pipe robot running gear.

In one embodiment, as shown in fig. 1 and 2, the front support 22 and the rear support 12 having the abutment portion 221 further include a support portion 223 and a spring 222, wherein two ends of the spring 222 are fixedly connected to the support portion 223 and the abutment portion 221, respectively, and the support portion 223 is used for abutting against the pipe wall. During operation, the spring 222 provides a greater supporting force for the supporting portion 223 when contracting, preventing the pipe robot running gear from toppling over.

In one embodiment, as shown in fig. 1 and 2, the pipe robot walking device further comprises a connection assembly, the connection assembly comprises a connection clamping seat 72 and a connection mounting seat 71, the connection mounting seat 71 is fixedly connected with the rear seat assembly 10, and an annular clamping groove 711 is formed in the side, away from the rear seat assembly 10, of the connection mounting seat 71 along the circumferential direction of the pipe.

The connection clamping seat 72 is provided with a rotary shifting piece 721, a connection short rod 722 and a fork-shaped connecting rod 723, the rotary shifting piece 721 is rotatably sleeved on the connection clamping seat 72, one end of the connection short rod 722 is rotatably connected with the rotary shifting piece 721, the other end of the connection short rod 722 is rotatably connected with one end of the fork-shaped connecting rod 723, the other end of the fork-shaped connecting rod 723 is connected with the inner wall of the connection clamping seat 72 through a torsion spring, the fork-shaped connecting rod 723 is provided with a pressing part 7231 for pressing the bottom of the annular clamping groove 711, and the connection clamping seat 72 is provided with a hollow cavity which can be used for installing a detection component. In the working process, the rotary pulling piece 721 is rotated to enable the fork-shaped connecting rod 723 to be separated from the annular clamping groove 711, so that the quick disassembly of the connecting clamping seat 72 and the connecting mounting seat 71 can be realized, after the connecting clamping seat 72 is installed and arranged, the rotary pulling piece 721 is rotated to enable the fork-shaped connecting rod 723 to be aligned with the annular clamping groove 711, the rotary pulling piece 721 is loosened, and under the action of a torsion spring, the fork-shaped connecting rod 723 tightly clamps the annular clamping groove 711.

The working principle of the pipeline robot walking device of the embodiment of the invention is as follows:

when the front support 22 is in the expanded state, the front support 22 supports the pipe wall, the friction force increases to make the front seat assembly 20 and the pipe relatively static, at this time, the rear support 12 is in the contracted state, the rear support 12 does not support the pipe wall, and the first link mechanism 30 is contracted, so that the rear seat assembly 10 can move forward.

When the rear support 12 is in the expanded state, the rear support 12 supports the pipe wall, the friction force increases to make the rear seat assembly 10 and the pipe relatively stationary, at this time the front support 22 is in the contracted state, the front support 22 does not support the pipe wall, and the first link mechanism 30 is expanded, so that the front seat assembly 20 can move forward.

1. according to the running device of the pipeline robot, through the cooperation and linkage among the first connecting rod mechanism, the second connecting rod mechanism and the third connecting rod mechanism, the front supporting piece and the rear supporting piece alternately support the pipe wall of the pipeline in a pressing mode, the movement of the whole running device is realized, the expansion and the driving control modes are simplified, and the movement, the expansion and the locking of the robot can be realized simultaneously only by driving a single signal source.

3. According to the pipeline robot walking device, the connecting assembly is arranged on the rear seat assembly, and the connecting assembly is used for realizing rapid installation of the detection part on the pipeline robot walking device through the rapid dismounting structure, so that the installation procedure is simplified, and the working efficiency is improved.

The above examples illustrate only a few embodiments of the invention, which are described in detail and are not to be construed as limiting the scope of the invention. It should be noted that it will be apparent to those skilled in the art that several variations and modifications can be made without departing from the spirit of the invention, which are all within the scope of the invention.

Claims

1. A pipe robot walking device, comprising:

a front seat assembly and a rear seat assembly which are oppositely arranged along the same axial direction; the front seat assembly comprises a front shell, two front supporting pieces and a front driver unit, wherein the two front supporting pieces are respectively arranged on two opposite sides of the front shell in a radial sliding manner, and the front driver unit is arranged on the front shell; the rear seat assembly comprises a rear shell, two rear supporting pieces and a rear driver unit, wherein the two rear supporting pieces are respectively arranged on two opposite sides of the rear shell in a radial sliding mode, and the rear driver unit is arranged on the rear shell; the radial end parts of the front shell, the front supporting piece, the rear shell and the rear supporting piece are all of arc structures, two sides of each arc structure are also provided with a cylinder structure, four arc grooves are respectively arranged on the corresponding cylinder positions of the front shell and the rear shell, and the cylinder structures can slide up and down in the arc grooves;

the front driver unit and the rear driver unit are connected through a first connecting rod mechanism so as to realize axial relative telescopic movement between the front seat assembly and the rear seat assembly; the front seat assembly is provided with a second link mechanism driven by the front driver unit, and the two front supporting pieces are connected through the second link mechanism; the rear seat assembly is provided with a third link mechanism driven by the rear driver unit, and the two rear supporting pieces are connected through the third link mechanism; the second link mechanism and the third link mechanism alternately act to realize the alternate contraction and expansion of the front support and the rear support along the radial direction;

the front driver unit comprises a front cam, a front rotating shaft and a front driving motor, wherein the front rotating shaft and the front driving motor are fixed on the front shell, the output end of the front driving motor is fixedly connected with the front rotating shaft through a gear set, and the front cam is fixed on the front rotating shaft; one of the front supporting pieces is provided with an abutting part which abuts against the wheel surface of the front cam, and two ends of the second connecting rod mechanism are respectively arranged on the two front supporting pieces so as to enable the two front supporting pieces to simultaneously stretch or expand;

the rear driver unit comprises a rear cam, a rear rotating shaft and a rear driving motor, wherein the rear rotating shaft and the rear driving motor are fixed on the rear shell, the output end of the rear driving motor is fixedly connected with the rear rotating shaft through a gear set, the rear cam is fixed on the rear rotating shaft, and the front cam and the rear cam are arranged in the same plane in a central symmetry manner; one side of the front cam and the rear cam is in a semicircular structure, and the circle centers of the semicircular structures of the front cam and the rear cam are respectively overlapped with the front rotating shaft and the rear rotating shaft; one of the rear supporting pieces is provided with an abutting part abutting against the wheel surface of the rear cam, the rear supporting piece in contact with the rear cam and the front supporting piece in contact with the front cam are positioned on the same side, and two ends of the third link mechanism are respectively arranged on the two rear supporting pieces so as to enable the two rear supporting pieces to simultaneously stretch or expand;

the first connecting rod mechanism comprises a first short rod and a first long rod, one end of the first short rod is fixedly connected with the rear rotating shaft, the other end of the first short rod is rotatably connected with one end of the first long rod, and the other end of the first long rod is rotatably connected with the front rotating shaft;

the second link mechanism comprises a second long rod and two groups of second short rods, one ends of the two groups of second short rods are respectively and rotatably connected with the corresponding front supporting pieces, the other ends of the two groups of second short rods are correspondingly and rotatably connected with the two ends of the second long rod, and the middle point of the second long rod is rotatably connected with the front rotating shaft;

the third link mechanism comprises an inner ring, an outer ring and two groups of third short rods, the inner ring is fixed on the side face of the rear shell, the outer ring is sleeved on the inner ring in a relatively rotatable manner, one ends of the two groups of third short rods are respectively connected with the corresponding rear supporting piece in a rotating manner, and the other ends of the two groups of third short rods are correspondingly connected with two opposite sides of the outer ring in a rotating manner;

the novel rotary table is characterized by further comprising a fourth connecting rod mechanism, wherein the fourth connecting rod mechanism comprises a fourth short rod and a fourth long rod, one end of the fourth short rod is fixedly connected with the front rotating shaft, the other end of the fourth short rod is rotatably connected with one end of the fourth long rod, and the other end of the fourth long rod is rotatably connected with the rear rotating shaft.

2. The pipe robot walking unit of claim 1, wherein:

the number of the first connecting rod mechanisms, the second connecting rod mechanisms and the third connecting rod mechanisms is two, and the first connecting rod mechanisms, the second connecting rod mechanisms and the third connecting rod mechanisms are correspondingly arranged on the left side and the right side of the front seat assembly and the rear seat assembly.

3. The pipe robot walking unit of claim 1, wherein:

the front support piece and the rear support piece with the abutting parts further comprise support parts and springs, two ends of each spring are fixedly connected with the corresponding support parts and the corresponding abutting parts respectively, and the support parts are used for abutting against pipe walls of pipelines.

4. The pipe robot walking unit of claim 1, wherein:

the connecting assembly comprises a connecting clamping seat and a connecting installation seat, the connecting installation seat is fixedly connected with the rear seat assembly, and an annular clamping groove is formed in one side, far away from the rear seat assembly, of the connecting installation seat along the circumferential direction of the pipeline;