Miniature wheel type pipeline robot

Abstract

The invention relates to the technical field of pipeline robots, and discloses a miniature wheel type pipeline robot which comprises a bending assembly, walking units are connected to the two ends of the bending assembly correspondingly, each walking unit comprises two wheel train assemblies, each wheel train assembly comprises a walking mechanism and a reducing mechanism, and each walking mechanism comprises a stator coil, a rotor, a rotating disc and a plurality of elastic wheel legs. The stator coil is matched with the rotor, the rotating disc and the rotor are coaxially fixed, the elastic wheel leg comprises an elastic piece and a walking wheel, the walking wheel is rotatably arranged at one end of the elastic piece, the other end of the elastic piece is fixedly connected with the rotating disc, the end, provided with the walking wheel, of the elastic piece stretches outwards, and a rotating shaft of the walking wheel inclines relative to the axis of the rotating disc. The elastic wheel legs are evenly distributed on the circumference, and the two wheel train assemblies are connected and symmetrically arranged. The diameter changing mechanism can enable the ends, away from the rotating disc, of the elastic pieces to be synchronously retracted inwards, and the bending assembly can enable the two walking units to be bent. The miniature wheel type pipeline robot is suitable for being used in a small-pipe-diameter multi-way pipe network.

Description

Technical Field

[0001] The invention relates to the technical field of pipeline robots, in particular to a micro wheeled pipeline robot. Background Art

[0002] In the fields of metallurgy, petroleum, biochemistry and other industrial applications, pipelines are often used for material transportation. With long-term operation, corrosion will inevitably occur on the inner wall of the pipeline. In order to prevent pipeline leakage and ensure production safety, the pipeline needs to be inspected and repaired regularly. The pipeline robot is a device that can automatically walk along the inside of the pipeline. It can be equipped with a variety of sensors to detect the inner wall of the pipeline.

[0003] Existing pipeline robots usually have two types of structures: peristaltic and wheeled. The wheeled pipeline robot structure can be found in a Chinese patent for a pipeline inspection robot (application number: CN201921190328.9), which includes a base and two wheel train components, which are coaxially arranged on the base and symmetrical to each other. The wheel train components include a driving wheel and a plurality of driven secondary wheels, each of which is connected to the driving wheel through a corresponding telescopic rod and evenly distributed around the driving wheel, and the rotation axis of the driven secondary wheels is inclined to the axis of the driving wheel. When in use, the pipeline inspection robot is arranged inside the pipeline, and each driven secondary wheel is pressed against the inner wall of the pipeline. By driving the two driving wheels to rotate on the base, the pipeline inspection robot can be driven to walk in the pipeline. Although the pipeline inspection robot can be used for walking in a single-line pipeline, in actual pipeline networks, it often involves multi-way pipelines such as tees and crosses. In multi-way pipelines, the pipeline inspection robot is difficult to pass through the multi-way joint position and cannot turn autonomously. In addition, the above-mentioned pipeline inspection robot also has the following defects: First, the two active wheels in the pipeline inspection robot are driven by a motor and a gear set structure. This structure occupies a large space, is not conducive to lightweight and simplified design, and cannot be applied to small-diameter pipelines; Second, the telescopic rod of the pipeline inspection robot is used to adjust the wheel train assembly to match the diameter of the pipeline to be measured before use. It does not have an active adjustment function after entering the pipeline, and is difficult to pass in some special cases, such as when there is a boss inside the variable-diameter pipeline.

[0004] In order to enable the wheeled pipeline robot to autonomously turn in multi-pass pipelines, corresponding research has also been carried out in the prior art. For example, a flexible pipeline robot (application number: CN201910356697.9) is provided with a walking motor, a rotating motor, a variable diameter motor, and a turning motor. The walking motor drives the driving wheel to rotate to drive the robot forward or backward, and the rotating motor rotates the driving wheel group to change the direction of travel of the driving wheel. The variable diameter motor adjusts the opening angle of the driving wheel group and the driven wheel group, and the turning motor realizes active turning control. Although the flexible pipeline robot can also realize the active turning of multi-pass pipelines and the passage of variable diameter pipelines, the setting of the above-mentioned motors makes the overall structure and control of the pipeline robot more complicated, which is not conducive to light simplification of design and cannot be applied in small-diameter pipelines. Summary of the invention

[0005] The purpose of the present invention is to overcome the shortcomings of the prior art and provide a micro wheeled pipeline robot which has a light and simple structure and has the functions of active turning and changing diameter in addition to walking in the pipeline. It is particularly suitable for use in pipelines of small diameter multi-pass pipeline networks.

[0006] The objective of the present invention is achieved through the following technical solutions: A miniature wheeled pipeline robot comprises a walking unit, wherein the walking unit comprises a housing assembly and two wheel train assemblies; the housing assembly comprises a coaxially arranged shell and a central axis, wherein the central axis penetrates the shell and is fixedly connected to the shell; the wheel train assembly comprises a walking mechanism, wherein the walking mechanism comprises a stator coil, a rotor, a rotating disk and a plurality of elastic wheel legs, wherein the stator coil is fixedly installed in the shell, wherein the rotor is rotatably sleeved on the central axis, wherein the stator coil and the rotor are adapted to each other, wherein the rotating disk is coaxially fixedly connected to the rotor, wherein the rotor can be driven to rotate when the stator coil is energized, thereby driving the rotating disk to rotate; wherein the elastic wheel leg comprises an elastic sheet and a walking wheel, wherein one end of the elastic sheet is connected to the The rotating disk is fixedly connected, and the other end of the elastic sheet is opened outwardly in the axial direction away from the central axis. The walking wheel is rotatably connected to the end of the elastic sheet away from the rotating disk. The rotating axis of the walking wheel is inclined to the axis of the central axis. A plurality of elastic wheel legs are evenly distributed around the circumference. When the walking unit is placed in a pipeline, each walking wheel can be pressed against the inner wall of the pipeline through each elastic sheet, and the walking unit can be centered to a position coaxial with the pipeline; the two wheel train assemblies are symmetrically arranged at both ends of the shell, and when the two rotating disks rotate synchronously in opposite directions, the walking unit can be driven to move axially in the pipeline and keep the casing assembly from rotating; when the two rotating disks rotate synchronously in the same direction, the casing assembly can be driven to rotate in situ.

[0007] Furthermore, the wheel train assembly also includes a diameter-changing mechanism, which is used to make the ends of the plurality of elastic sheets away from the rotating disk converge toward the axial direction of the central axis synchronously, and in the converged state, the radial dimensions of the positions of the running wheels become smaller.

[0008] Specifically, the variable diameter mechanism includes a first SMA spring, a pull disk, a pull ring, a wire ring and a plurality of pull ropes. The first SMA spring, pull ring and wire ring are coaxially arranged outside the central axis in sequence. The pull disk and the pull ring are coaxially rotatably connected. One end of the first SMA spring is fixedly connected to the central axis, and the other end of the first SMA spring is fixedly connected to the pull disk. The pull ring and the wire ring are slidably connected, and the wire ring is fixedly connected to the rotating disk. A plurality of pull ropes are respectively adapted to a plurality of elastic sheets. One end of the pull rope is fixedly connected to an end of the elastic sheet away from the rotating disk, and the other end of the pull rope is fixedly connected to the pull ring after passing around the wire ring. The pull disk can be driven to slide by the first SMA spring, and then each elastic sheet can be pulled toward the direction of the wire ring by the pull ring and the pull rope to complete the aforementioned contraction process.

[0009] Specifically, the wire ring is provided with a plurality of wire holes, the wire holes comprising a first guide hole and a second guide hole, the first guide hole is arranged along the radial direction of the wire ring, the second guide hole is parallel to the central axis, one end of the second guide hole is connected to the first guide hole, and the other end of the second guide hole is arranged toward the pull ring, and the end of the pull rope away from the elastic sheet passes through the first guide hole and the second guide hole in sequence and is fixedly connected to the pull ring.

[0010] Furthermore, the central axis is a hollow tube structure, and the wires of each stator coil and the first SMA spring can be placed in the inner hollow position of the central axis.

[0011] Furthermore, the micro wheeled pipeline robot includes the two aforementioned walking units, and is also provided with a bending assembly, wherein the bending assembly includes a central block and two swinging mechanisms, wherein the swinging mechanism includes a swing arm and a driving element, wherein one end of the swing arm is rotatably connected to the central block, and the driving element is used to drive the swing arm to swing around the central block, and the two swinging mechanisms are symmetrically arranged at both ends of the central block, and the ends of the two swing arms away from the central block are respectively fixedly connected to the ends of the two central axes, and the two swing arms can be swung until the two central axes are coaxial, and the bending assembly and the wheel train components cooperate to realize the active steering of the micro wheeled pipeline robot in a multi-pass pipeline network.

[0012] Specifically, a limiting portion is provided on the central block, and the limiting portion is used to limit the two swing arms when the two central axes are coaxial. The driving element includes a second SMA spring and a torsion spring, and the torsion spring is used to provide an elastic force for causing the swing arm to swing toward a direction close to the limiting portion. Both ends of the second SMA spring are respectively connected to the central block and the swing arm, and the second SMA spring can cause the swing arm to swing toward a direction away from the limiting portion.

[0013] The beneficial effects of the present invention are: A miniature wheeled pipeline robot comprises a bending component and two walking units.

[0014] The walking unit includes a housing assembly and two wheel train assemblies, and the wheel train assemblies include a walking mechanism, and the walking mechanism includes a stator coil, a rotor, a rotating disk and a plurality of elastic wheel legs, and the plurality of elastic wheel legs are evenly distributed around the circumference; the elastic wheel legs include an elastic sheet and a walking wheel, one end of the elastic sheet is fixedly connected to the rotating disk, and the other end of the elastic sheet is opened outward, and the walking wheel is rotatably connected to the end of the elastic sheet away from the rotating disk, and the rotating shaft of the walking wheel is inclined to the axis of the rotating disk. When the walking unit is placed in a pipeline, the elastic force of each elastic sheet can press each walking wheel against the inner wall of the pipeline on the one hand, and the walking unit can be centered to the axis position of the pipeline on the other hand. The rotating disk and the rotor are coaxially fixedly connected. The casing assembly includes a coaxially arranged shell and a central axis. The central axis passes through the shell and is fixedly connected to the shell. The stator coil is fixedly installed on the shell. The rotor is rotatably mounted on the central axis. When the stator coil is energized, the rotor can be driven to rotate, thereby driving the rotating disk and each elastic wheel leg to rotate. Since the axis of each walking wheel is inclined with the axis of the rotating disk and the pipeline, when the rotating disk rotates, each walking wheel position is subjected to a reaction force along the axial direction of the walking wheel. The reaction force can be decomposed into an axial component and a tangential component. The two wheel train assemblies are symmetrically arranged at both ends of the casing assembly, so that the two walking mechanisms are symmetrical to each other. When the two rotating disks rotate synchronously in opposite directions, the walking unit can be driven to move axially in the pipeline and keep the casing assembly from rotating; when the two rotating disks rotate synchronously in the same direction, the casing assembly can be driven to rotate in situ. It can be seen that the walking unit can be used alone as a pipeline robot. When in use, the walking wheels can be pressed against the inner wall of the pipeline through the action of various elastic sheets to ensure stable driving. At the same time, the walking unit can be centered to the pipeline axis to maintain accurate position. In terms of drive structure, the frameless motor design concept is adopted, which makes the overall structure of the walking unit simpler and has smaller radial and axial dimensions, making it suitable for use in small-diameter pipelines.

[0015] The wheel train assembly also includes a reducing mechanism, which can make several elastic sheets converge inward synchronously away from one end of the rotating disk. On the one hand, when the walking unit encounters a large protruding obstacle in the pipeline, the reducing mechanism can actively converge the elastic sheets to pass smoothly; on the other hand, when the walking unit moves to the multi-way joint position of the multi-way pipeline, the reducing mechanism can actively converge the elastic sheets to avoid interference, thereby improving the passing capacity of the walking unit and being suitable for different types of pipelines.

[0016] The bending assembly includes a central block and two swinging mechanisms, the swinging mechanism includes a swing arm and a driving element, one end of the swing arm is rotatably connected to the central block, and the driving element is used to drive the swing arm to swing around the central block; the two swinging mechanisms are symmetrically arranged at both ends of the central block, and the ends of the two swing arms away from the central block are respectively fixedly connected to the ends of the two central axes, and the two swing arms can be swung until the two central axes are coaxial. As the overall implementation structure of the micro wheeled pipeline robot, it includes four wheel train components. When the two central axes are in a coaxial position, the four wheel train components are arranged in sequence, and the two wheel train components at the two ends are symmetrically structured. When the two wheel train components in the middle are in a convergent state, the micro wheeled pipeline robot is similar to the structural form of a single walking unit, and can be driven to move axially and rotate in situ in the pipeline in the aforementioned manner; at the same time, when the two wheel train components of a walking unit are in a convergent state, the two wheel train components of another walking unit can be opened to keep the centering support of the micro wheeled pipeline robot in the pipeline stable and drive the micro wheeled pipeline robot to move axially and rotate in situ in the pipeline; in addition, the driving element can drive the swing arm to swing, and the swinging action cooperates with the convergent action of each wheel train component, the axial walking and situ rotation action of the micro wheeled pipeline robot in the pipeline, so that the micro wheeled pipeline robot can actively turn and pass smoothly in the multi-channel pipeline. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 This is a schematic diagram of the structure of a walking unit in a micro wheeled pipeline robot of the present invention; Figure 2 for Figure 1 A schematic diagram of the structure of the gear train assembly in the walking unit shown; Figure 3 for Figure 2 A schematic diagram of the disassembled structure of the gear train assembly shown; Figure 4 for Figure 1 A schematic diagram of the structure of the housing assembly in the walking unit shown; Figure 5 This is a schematic diagram of the overall structure of a micro wheeled pipeline robot of the present invention; Figure 6This is a schematic structural diagram of a bending component in a micro wheeled pipeline robot of the present invention; In the figure, 10-casing assembly, 11-casing, 12-center axis, 20-gear train assembly, 21-stator coil, 22-rotor, 23-rotating disk, 24-elastic sheet, 25-traveling wheel, 26-first SMA spring, 27-pull disk, 28-pull ring, 29-wire ring, 30-wire hole, 31-center block, 32-swing arm, 33-limiting part, 34-second SMA spring, 35-torsion spring. DETAILED DESCRIPTION

[0018] The technical solution of the present invention is further described in detail below in conjunction with the accompanying drawings, but the protection scope of the present invention is not limited to the following.

[0019] A micro wheeled pipeline robot comprises Figure 1 The walking unit shown includes a casing assembly 10 and two wheel train assemblies 20 .

[0020] like Figure 4 As shown, the housing assembly 10 includes a shell 11 and a central axis 12 . The central axis 12 is coaxial with the shell 11 . The central axis 12 passes through the shell 11 and is fixedly connected to the shell 11 . Installation cavities are machined inwardly at both ends of the shell 11 .

[0021] like Figure 2 , Figure 3 As shown, the wheel train assembly 20 includes a walking mechanism, which includes a stator coil 21, a rotor 22, a rotating disk 23 and a plurality of elastic wheel legs. The stator coil 21 is fixedly installed in the installation cavity of the housing 11, and the rotor 22 is rotatably sleeved on the central shaft 12 through a bearing. The stator coil 21 and the rotor 22 are adapted to each other, and the rotating disk 23 is coaxially fixedly connected with the rotor 22. A frameless motor structure design is adopted here. When the stator coil 21 is energized, the rotor 22 and the rotating disk 23 can be driven to rotate. The speed of the rotor 22 can be adjusted by adjusting the magnitude of the energized current, and the rotation direction of the rotor 22 can be changed by changing the energization direction. The above-mentioned elastic wheel legs include an elastic sheet 24 and a walking wheel 25, one end of the elastic sheet 24 is fixedly connected to the outer peripheral side of the rotating disk 23, and the other end of the elastic sheet 24 is outwardly opened in the axial direction away from the central shaft 12; the walking wheel 25 is rotatably connected to one end of the elastic sheet 24 away from the rotating disk 23, and the rotating axis of the walking wheel 25 is inclined to the axis of the central shaft 12. In the wheel train assembly 20 , a plurality of elastic wheel legs are evenly distributed around the circumference of the central shaft 12 .

[0022] like Figure 1As shown, in the walking unit, two wheel train assemblies 20 are symmetrically arranged at both ends of the housing 11. As an implementation form, the walking unit can be used alone as a pipeline robot. When the walking unit is placed in a pipeline (the diameter of the pipeline is smaller than the distance between the walking wheels 25 and the axis of the central axis 12 when each walking wheel 25 in the wheel train assembly 20 is naturally opened outward), each elastic sheet 24 makes one end of the walking wheel 25 installed have the elasticity to open outward, so each walking wheel 25 can be pressed against the inner wall of the pipeline. At the same time, since a plurality of elastic wheel legs are arranged in the wheel train assembly 20 and each elastic wheel leg is evenly distributed around the circumference, it is similar to the principle of a claw, and the position of the walking unit can also be located so that the central axis 12 is centered to be coaxial with the pipeline. Thereafter, energizing the two stator coils 21 can respectively drive the two rotating disks 23 to rotate, thereby driving the travel unit to move axially or rotate in the pipeline. Specifically: in a wheel train assembly 20, since the rotation axis of each travel wheel 25 is inclined to the axis of the central axis 12, when the rotating disk 23 drives the elastic wheel legs connected thereto to rotate, each travel wheel 25 will be subjected to a force along the direction of its rotation axis (similar to the McRae wheel principle), and the force can be decomposed into an axial component and a tangential component, wherein the axial component is parallel to the axis of the pipeline, and the tangential component is equivalent to the rotational torque. Since the two wheel train assemblies 20 are symmetrically arranged, the walking wheels 25 in the two wheel train assemblies 20 are tilted in opposite directions. When the two rotating disks 23 rotate synchronously in opposite directions, the rotational torques received by the two elastic wheel legs cancel each other out and the axial forces are superimposed on each other. At this time, the walking unit can be driven to move axially in the pipeline and maintain the posture of the casing assembly 10 (the casing assembly 10 will not rotate); when the two rotating disks 23 rotate synchronously in the same direction, the rotational torques received by the two elastic wheel legs are superimposed on each other and the axial forces are superimposed on each other. At this time, the casing assembly 10 can be driven to rotate in situ to adjust the posture; in addition, when the rotation speeds of the two rotating disks 23 are not synchronized, the walking unit can move axially in the pipeline, and the casing assembly 10 will rotate during the walking process.

[0023] According to the above, the walking unit can move axially in the pipeline and can rotate in situ. After the corresponding sensor is installed on the housing component 10, it can be used to detect the inner wall of the pipeline. In specific applications, taking the pipe diameter measurement as an example, by measuring the diameter of each part in the pipeline, it can be identified whether the inner wall of the pipeline is worn, rusted, scaled, etc., at this time, the housing component 10 can be equipped with a distance sensor, so that the distance sensor is set along the radial direction of the central axis 12, and the circumferential distance scanning can be achieved by driving the housing component 10 to rotate in situ, and the axial position of the scanning slice can be adjusted by driving the walking unit to move axially. Since the walking unit can be centered at the pipeline axis position through the elastic force of each elastic sheet 24 as mentioned above, the position between the distance sensor and the pipeline axis can be kept fixed, which is conducive to ensuring the accuracy of its measurement; at the same time, the setting of the elastic sheet 24 is also conducive to keeping each walking wheel 25 pressed against the inner wall of the pipeline to ensure reliable driving, and also has a higher obstacle crossing ability when there are raised areas such as rust and scale on the inner wall of the pipeline. In terms of driving, each wheel train assembly 20 is composed of only a stator coil 21 and a rotor 22 to form a driving structure. The aforementioned motion control can be achieved by adjusting the current direction and magnitude of the two stator coils 21. The entire control process is simple. At the same time, the frameless motor design concept is adopted to make the walking unit highly integrated in structure. The casing assembly 10 can have smaller radial and axial dimensions and can be suitable for use in small-diameter pipelines.

[0024] Furthermore, the above-mentioned wheel train assembly 20 also includes a diameter-changing mechanism, which is used to make the end of the plurality of elastic sheets 24 away from the rotating disk 23 converge toward the axis direction of the central axis 12 synchronously, so as to adjust the radial distance between each running wheel 25 and the axis of the central axis 12. In some special cases, such as when there is a large boss inside the variable diameter pipeline, since each elastic sheet 24 presses the running wheel 25 against the inner wall of the pipeline by elastic force, in the process of moving from the large diameter part to the small diameter part of the variable diameter pipeline, the running unit will find it difficult to cross the large raised obstacle. The setting of the diameter-changing mechanism can actively converge each elastic sheet 24 when encountering this situation, so that it can smoothly pass through these raised obstacles and enter the small diameter part; in addition, when used for active steering of multi-way pipelines (see below for details), the diameter-changing mechanism can also be used to converge the elastic sheet 24 to avoid interference caused by the wheel train assembly 20 at the multi-way joint position. The above-mentioned diameter-changing mechanism can adopt a variety of structural forms. For example, a closing ring is set in the wheel train assembly 20, and the closing ring is coaxially arranged with the housing assembly 10 and slidably connected, so that each elastic sheet 24 of the wheel train assembly 20 passes through the closing ring, and the closing ring is driven to slide in the direction of the running wheel 25 to complete the above-mentioned diameter-changing and closing process.

[0025] In this embodiment, Figures 1 to 3As shown, the diameter-changing mechanism includes a first SMA spring 26, a pull disc 27, a pull ring 28, a wire ring 29 and a plurality of pull ropes (not shown). The first SMA spring 26, the pull ring 28 and the wire ring 29 are coaxially arranged outside the central axis 12 in sequence, the pull disc 27 and the pull ring 28 are coaxially rotatably connected, one end of the first SMA spring 26 is fixedly connected to the central axis 12, the other end of the first SMA spring 26 is fixedly connected to the pull disc 27, the pull ring 28 is slidably connected to the wire ring 29, and the wire ring 29 is fixedly connected to the rotating disc 23 through a plurality of connecting plates. The plurality of pull ropes are respectively adapted to the plurality of elastic sheets 24, one end of the pull rope is fixedly connected to the end of the elastic sheet 24 away from the rotating disc 23, and the other end of the pull rope is fixedly connected to the pull ring 28 after passing the wire ring 29. The wire loop 29 is used to limit and guide the pull rope. In the specific implementation, a plurality of wire holes 30 are provided on the wire loop 29. The wire holes 30 include a first guide hole and a second guide hole. The first guide hole is arranged along the radial direction of the wire loop 29, and the second guide hole is parallel to the central axis 12. One end of the second guide hole is connected to the first guide hole, and the other end of the second guide hole is arranged toward the pull ring 28. The end of the pull rope away from the elastic sheet 24 passes through the first guide hole and the second guide hole in sequence and is fixedly connected to the pull ring 28. The first SMA spring 26 is made of shape memory alloy material. After being energized, it can be deformed and contracted under the thermal effect, thereby pulling the pull disk 27 to slide toward the housing 11, and further tightening the end of each elastic sheet 24 away from the rotating disk 23 toward the wire loop 29 through each pull rope, thereby completing the aforementioned diameter-changing and convergence process; because each elastic sheet 24 has an outward elastic force, the first SMA spring 26 can be quickly restored by de-energizing in the convergence state. The diameter-changing mechanism adopts the above-mentioned design, and its overall structure surrounds the central axis 12, which is conducive to reducing the radial size and is suitable for use in small-diameter pipes. When it is in use, the pull ring 28 and the wire ring 29 can rotate with the rotating disk 23 to avoid the entanglement of the pull rope and ensure the reliability of the diameter-changing and converging process.

[0026] Specifically, the central shaft 12 is a hollow tube structure. In the aforementioned structure, the central shaft 12, the stator coil 21, and the first SMA spring 26 are relatively fixed. The wires of the stator coil 21 and the first SMA spring 26 can directly pass through the hollow inner cavity of the central shaft 12 and be connected to the external power supply and control equipment of the pipeline. There is no need to set an unwinding structure for the wires, and the wiring is convenient. The wires are stored in the central shaft 12, which also makes the overall structure of the walking unit compact and clean.

[0027] Further, such as Figure 5 As shown in FIG. 1 , as an overall implementation form, the micro wheeled pipeline robot includes two walking units as described above, and a bending component is also provided between the two walking units. Figure 6As shown, the bending assembly includes a central block 31 and two swing mechanisms, the swing mechanisms include swing arms 32 and a driving element, one end of the swing arm 32 is rotatably connected to the central block 31, and the driving element is used to drive the swing arm 32 to swing around the central block 31. The two swing mechanisms are symmetrically arranged at both ends of the central block 31, and the ends of the two swing arms 32 away from the central block 31 are respectively fixedly connected to the ends of the two central shafts 12, and the two swing arms 32 can swing to make the two central shafts 12 coaxial. The micro wheeled pipeline robot includes four wheel train components 20, which are described in order for convenience. Figure 5 As shown, from left to right, they are named as the No. 1 gear train, the No. 2 gear train, the No. 3 gear train, and the No. 4 gear train. Since the two swing mechanisms are symmetrically arranged at both ends of the central block 31, when the two central axes 12 are coaxial, the two walking units are symmetrical to each other. At this time, the No. 1 gear train and the No. 2 gear train, the No. 1 gear train and the No. 4 gear train, and the No. 3 gear train and the No. 4 gear train are all in a symmetrical relationship.

[0028] The above-mentioned micro wheeled pipeline robot can be used in multi-way pipelines. When in use, the micro wheeled pipeline robot is first adjusted to the coaxial state of the two central axes 12 and placed in one of the pipelines in the multi-way pipeline. The corresponding diameter reducing mechanism is used to reduce the diameter of each elastic sheet 24 of the second and third gear trains, so that each walking wheel 25 of the second and third gear trains is away from the inner wall of the pipeline. At this time, the micro wheeled pipeline robot is supported by the first and fourth gear trains. Its overall structure is similar to that of a single walking unit, and it can walk axially and rotate in place in the pipeline in the above-mentioned manner. Assuming that the direction of the first gear train is the front of the axial travel, when the front is close to the multi-way joint position, it can actively turn according to the following steps: S1, releasing the contracted state through the diameter reducing mechanism of the third gear train, so that each running wheel 25 of the third gear train is stretched outward and pressed against the inner wall of the pipe; S2, the diameter-changing mechanism of the first gear train is used to reduce the diameters of the elastic sheets 24 of the first gear train, and the running wheels 25 of the first and second gear trains are all reduced to a position away from the inner wall of the pipeline, and the micro wheeled pipeline robot is supported by the third and fourth gear trains; S3, the central shaft 12 is rotated by the actions of the third and fourth gear trains, thereby driving the bending assembly to rotate to match the direction to be turned; S4, the swing arm 32 is driven to swing by the driving element, so that the front walking unit (the walking unit to which the No. 1 and No. 2 gear trains belong) is gradually bent in the direction to be turned, and at the same time, the No. 3 and No. 4 gear trains drive the pipeline robot to move axially while keeping the bending assembly fixed, and the bending action and the axial movement action are controlled in coordination until the front walking unit extends into another pipeline to be turned; S5, the diameter reducing mechanism of the first and second gear trains is released from the contracted state, and the running wheels 25 of the first and second gear trains are stretched outward and pressed against the inner wall of the pipe into which they turn; S6, the diameter-changing mechanisms of the third and fourth gear trains perform a diameter-changing and convergence action, so that the running wheels 25 of the third and fourth gear trains are away from the inner wall of the pipe where they are located. At this time, the micro wheeled pipeline robot is supported by the first and second gear trains; S7, the swing arm 32 is driven to swing by the driving element, so that the rear travel unit (the travel unit to which the No. 3 and No. 4 gear trains belong) is gradually reset, and at the same time, the No. 1 and No. 2 gear trains drive the pipeline robot to move axially forward while keeping the bending assembly fixed, and the reset action and the axial movement action are coordinated and controlled until the rear travel unit is transferred into the pipeline to be turned; S8, the diameter-changing mechanism of the fourth gear train releases the contracting state, and then the diameter-changing mechanism of the second gear train performs the diameter-changing contracting action, and the micro-wheeled pipeline robot returns to the state supported by the first gear train and the fourth gear train.

[0029] According to the above working process, the micro wheeled pipeline robot can walk along the axial direction of the pipeline in a multi-pass pipeline and can rotate in situ in the pipeline. It can also actively turn in all directions at the multi-pass joint position to meet the use requirements in multi-pass pipelines. In terms of specific structural design, each walking unit can effectively reduce its radial and axial dimensions in the converged state through a compact design, which is also conducive to its smooth turning in a small-diameter multi-pass pipeline network.

[0030] The driving element can be in various structural forms. For example, in the application scenario where the pipe diameter is large, a steering gear can be used, so that the steering gear is fixedly connected to the central block 31, and the output shaft of the steering gear is connected to the swing arm 32 as the rotating shaft for the swing arm 32 to rotate relative to the central block 31, so that the swing arm 32 can be driven by the steering gear to swing. Figure 6 As shown, a limiting portion 33 is provided on the center block 31, and the limiting portion 33 is used to limit and block the two swing arms 32 when the two center axes 12 are coaxial. The aforementioned driving element includes a second SMA spring 34 and a torsion spring 35, and the torsion spring 35 is used to provide an elastic force to swing the swing arm 32 toward the limiting portion 33. In a natural state, the elastic force of the torsion spring 35 makes the swing arm 32 lean against the limiting portion 33. At this time, the two center axes 12 are coaxial, and the elastic force of the torsion spring 35 enables this state to maintain the required stiffness, and the coaxial state of the two center axes 12 is always maintained in the aforementioned step S3; the two ends of the second SMA spring 34 are respectively connected to the center block 31 and the swing arm 32, and the second SMA spring 34 is energized to compress it, which can drive the swing arm 32 to swing in the direction away from the limiting portion 33. It should be noted that Figure 6The figure is only a schematic diagram of the structure of the bending assembly. Since the bending action or the resetting action in the aforementioned steps S4 and S7 needs to be coordinated with the axial movement action, in actual applications, the second SMA spring 34 is composed of multiple sections of memory alloy springs connected in series, and each section of the memory alloy spring can be controlled separately to facilitate coordination with the axial movement action described in steps S4 and S7.

[0031] The above is only a preferred embodiment of the present invention. It should be understood that the present invention is not limited to the form disclosed herein, and should not be regarded as excluding other embodiments, but can be used in various other combinations, modifications and environments, and can be modified within the scope of the concept described herein through the above teachings or the technology or knowledge of the relevant field. The changes and modifications made by those skilled in the art shall not deviate from the spirit and scope of the present invention, and shall be within the scope of protection of the claims attached to the present invention.

Claims

1. A miniature wheeled pipeline robot, characterized in that: It includes a walking unit, and the walking unit includes a housing assembly and two wheel train assemblies; The housing assembly comprises a coaxially arranged housing and a central axis, wherein the central axis penetrates the housing and is fixedly connected to the housing; The wheel train assembly includes a walking mechanism, which includes a stator coil, a rotor, a rotating disk and a plurality of elastic wheel legs. The stator coil is fixedly installed in the housing, the rotor is rotatably sleeved on the central axis, the stator coil and the rotor are adapted to each other, and the rotating disk is coaxially and fixedly connected with the rotor. The elastic wheel leg comprises an elastic sheet and a running wheel, one end of the elastic sheet is fixedly connected to the rotating disk, the other end of the elastic sheet is outwardly opened in the axial direction away from the central axis, the running wheel is rotatably connected to the end of the elastic sheet away from the rotating disk, the rotating axis of the running wheel is inclined to the axis of the central axis, and a plurality of the elastic wheel legs are evenly distributed around the circumference; The two wheel train assemblies are symmetrically arranged at two ends of the housing.

2. A micro wheeled pipeline robot according to claim 1, characterized in that: The gear train assembly further comprises a diameter-changing mechanism, and the diameter-changing mechanism is used to make the ends of the plurality of elastic sheets away from the rotating disk converge toward the axial direction of the central axis synchronously.

3. A micro wheeled pipeline robot according to claim 2, characterized in that: The diameter-changing mechanism includes a first SMA spring, a pull disc, a pull ring, a wire ring and a plurality of pull ropes. The first SMA spring, the pull ring, and the wire ring are coaxially arranged outside the central axis in sequence, the pull disk is coaxially rotatably connected to the pull ring, one end of the first SMA spring is fixedly connected to the central axis, the other end of the first SMA spring is fixedly connected to the pull disk, the pull ring is slidably connected to the wire ring, and the wire ring is fixedly connected to the rotating disk. The plurality of pull ropes are respectively matched with the plurality of elastic sheets, one end of the pull rope is fixedly connected to one end of the elastic sheet away from the rotating disk, and the other end of the pull rope is fixedly connected to the pull ring after passing around the wire ring.

4. A micro wheeled pipeline robot according to claim 3, characterized in that: The wire ring is provided with a plurality of wire holes, the wire holes comprising a first guide hole and a second guide hole, the first guide hole being arranged along the radial direction of the wire ring, the second guide hole being parallel to the central axis, one end of the second guide hole being connected to the first guide hole, the other end of the second guide hole being arranged toward the pull ring, and the end of the pull rope away from the elastic sheet passing through the first guide hole and the second guide hole in sequence and then being fixedly connected to the pull ring.

5. The micro wheeled pipeline robot according to claim 3, characterized in that: The central axis is a hollow tube structure.

6. A micro wheeled pipeline robot according to any one of claims 2 to 5, characterized in that: It includes two walking units, and is also provided with a bending assembly, wherein the bending assembly includes a central block and two swing mechanisms. The swing mechanism comprises a swing arm and a driving element, one end of the swing arm is rotatably connected to the central block, and the driving element is used to drive the swing arm to swing around the central block. The two swing mechanisms are symmetrically arranged at two ends of the central block, and the ends of the two swing arms away from the central block are fixedly connected to the ends of the two central shafts respectively, and the two swing arms can swing until the two central shafts are coaxial.

7. The micro wheeled pipeline robot according to claim 6, characterized in that: A limiting portion is provided on the central block, and the limiting portion is used to limit the two swing arms when the two central axes are coaxial. The driving element includes a second SMA spring and a torsion spring, wherein the torsion spring is used to provide an elastic force to make the swing arm swing toward a direction close to the limiting portion, and the two ends of the second SMA spring are respectively connected to the center block and the swing arm, and the second SMA spring can make the swing arm swing toward a direction away from the limiting portion.

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