In-pipe mobile robot

JP2026125260AActive Publication Date: 2026-08-03株式会社ソラリス
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Patent Information

Authority / Receiving Office
JP · JP
Patent Type
Applications
Current Assignee / Owner
株式会社ソラリス
Filing Date
2025-01-22
Publication Date
2026-08-03

AI Technical Summary

Benefits of technology

【0013】 本発明によれば、管の屈曲部分を確実に通過することが可能な管内移動ロボットを提供することができる。

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Abstract

The objective is to provide a pipe-mobile robot capable of reliably navigating the bent sections of pipes. [Solution] A pipe-in-pipe mobile robot 1 comprising a robot body 10 having at least three telescopic units 11, the pipe-in-pipe mobile robot 1 comprising a tip body portion 21 that constitutes the tip of the pipe-in-pipe mobile robot 1, a tip attitude maintenance portion 20 having a pair of elastic bodies 22, 23 that protrude radially outward from the outer peripheral surface of the tip body portion 21 and are arranged at an axial distance from each other, and an elastically deformable elastic connection portion 40 provided between the tip attitude maintenance portion 20 and the robot body 10.
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Description

Technical Field

[0006] , ,

[0005] ,

[0001] The present invention relates to an in-pipe moving robot that moves inside a pipe.

Background Art

[0002] For example, there is known an in-pipe moving robot configured to move inside a bent pipe such as an air duct for an air conditioner provided in an office building, a factory, a detached house, etc. (see, for example, Patent Document 1). Such an in-pipe moving robot is used for various applications such as cleaning the inside of the pipe and inspecting the inside of the pipe.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] As an in-pipe moving robot, there is one provided with a robot body having at least three expansion and contraction units that expand in the radial direction and contract in the axial direction when fluids are respectively supplied, and configured to move inside the pipe by the at least three expansion and contraction units performing peristaltic motion in a predetermined pattern. In such an in-pipe moving robot, in order to be able to smoothly pass through the bent portion of the pipe, it is common to provide a tapered tip portion at the front end of the robot body via a compression spring.

[0005] However, even in a configuration where a tapered tip portion is provided at the front end of the robot body via a compression spring, if there is a step such as a connection portion of an elbow forming the bent portion on the inner peripheral surface of the bent portion of the pipe, there is a risk that the tip portion will be caught by the step and the in-pipe moving robot will not be able to move forward.

[0006] This invention has been made in view of these problems, and its objective is to provide a pipe-moving robot that can reliably pass through bent sections of pipes. [Means for solving the problem]

[0007] The pipe-moving robot of the present invention comprises a robot body equipped with at least three expandable / contractible units, each of which expands radially and contracts axially when fluid is supplied, and is configured to move inside a pipe by the peristaltic motion of the expandable / contractible units in a predetermined pattern, and is characterized by comprising: a tip body portion that constitutes the tip of the pipe-moving robot; a tip attitude maintenance portion having a pair of elastic bodies, each being annular in shape with a roughly circular or regular polygonal outer circumference centered on the axis of the tip body portion, projecting radially outward from the outer surface of the tip body portion and spaced apart from each other in the axial direction; and an elastically deformable elastic connection portion provided between the tip attitude maintenance portion and the robot body.

[0008] In the above configuration, the pipe-mobilizing robot of the present invention preferably further includes an angle-regulating joint provided between the elastic connection part and the robot body, which allows the tip attitude maintenance part to be bent at an angle of less than 90 degrees relative to the robot body.

[0009] In the pipe-mobile robot of the present invention, it is preferable that the protruding portion of the tip body that extends forward from the pair of elastic bodies is contained within the range of a virtual spherical surface in which the outer peripheral ends of each of the pair of elastic bodies are inscribed over their entire circumference.

[0010] In the pipe-mobile robot of the present invention, it is preferable that the elastic body on the rear side is more flexible than the elastic body on the front side.

[0011] In the pipe-mobile robot of the present invention, it is preferable that a camera is provided on the axis of a protruding portion that protrudes forward from the pair of elastic bodies of the tip body portion in the above configuration.

[0012] The pipe-moving robot of the present invention, in the above configuration, comprises an inner cylindrical body formed in a cylindrical shape with elasticity, and an outer cylindrical body formed in a cylindrical shape with elasticity and arranged on top of the outer surface of the inner cylindrical body, and has a cover configured such that the frictional resistance generated between the inner cylindrical body and the outer cylindrical body is smaller than the frictional resistance generated between the outer cylindrical body and the inner surface of the pipe, and preferably the cover covers the angle-regulating joint portion. [Effects of the Invention]

[0013] According to the present invention, it is possible to provide a pipe-moving robot that can reliably pass through bent sections of pipes. [Brief explanation of the drawing]

[0014] [Figure 1] This is a side view of a pipe-in-pipe mobile robot according to the first embodiment of the present invention. [Figure 2] Figure 1 is a schematic diagram illustrating the operating pattern of the retractable unit during the peristaltic motion of the robot body. [Figure 3] Figure 1 is a magnified side view showing the main components of the in-pipe mobile robot. [Figure 4] This diagram shows the state of the robot moving inside the pipe when the tip attitude maintenance unit is moving along the bent section of the pipe. [Figure 5] (a) to (f) are explanatory diagrams showing the movement of the bent portion of the tube in the tip posture maintenance section. [Figure 6] This diagram shows the state of the pipe-moving robot when the angle-regulating joint begins to move along the bent portion of the pipe. [Figure 7] This diagram shows the state of the robot moving through the pipe when the angle-regulating joint has finished moving through the bent portion of the pipe. [Figure 8] This is an enlarged side view showing the main parts of a pipe-in-pipe mobile robot according to a second embodiment of the present invention. [Figure 9] This is a cross-sectional view along line AA in Figure 8. [Figure 10]It is an explanatory diagram showing the state when passing through the bent portion of the tube of the cover shown in FIG. 9. [Figure 11] It is a side view showing an enlarged view of the main part of the in-tube moving robot according to the third embodiment of the present invention. [Figure 12] (a) to (c) are explanatory diagrams showing the angle regulation joint portions in the states where the positions of the stoppers are changed, respectively. [Figure 13] It is a side view showing an enlarged view of the main part of the in-tube moving robot according to the fourth embodiment of the present invention. [Figure 14] (a) to (f) are explanatory diagrams showing the states of movement of the tip attitude maintaining portion at the bent portion of the tube shown in FIG. 13, respectively.

Mode for Carrying Out the Invention

[0015] Hereinafter, the in-tube moving robot of the present invention will be exemplified and described in detail with reference to the drawings.

[0016] The in-tube moving robot 1 according to the first embodiment of the present invention shown in FIG. 1 is configured to move inside a meandering tube such as an air duct for an air conditioner provided in, for example, an office building, a factory, a detached house, etc.

[0017] The in-tube moving robot 1 has a robot body 10, a tip attitude maintaining portion 20, an angle regulation joint portion 30, and an elastic connection portion 40.

[0018] The robot body 10 is also called an earthworm-type robot, a creeping-type robot, etc., and has an elongated form extending along the axis O. The robot body 10 can move in the axial direction inside the tube, that is, in the direction along the axis O. That is, the robot body 10 can move forward inside the tube. Note that the robot body 10 may be configured to be able to move forward and backward inside the tube.

[0019] The robot body 10 is equipped with at least three telescopic units 11 as a drive source for moving inside the pipe. In this embodiment, the robot body 10 is equipped with seven telescopic units 11 (only four telescopic units 11 are shown in Figure 1). The number of telescopic units 11 can be changed as appropriate, as long as the robot body 10 is equipped with at least three telescopic units 11.

[0020] The expandable / contractible unit 11 is also called an artificial muscle. The expandable / contractible unit 11 has a cylindrical portion 11a formed from an elastic material such as rubber, with an axis O. Both axial ends of the cylindrical portion 11a are closed. Inside the cylindrical portion 11a, multiple fiber bundles (not shown) with high tensile strength are arranged along the axial direction. As a result, the cylindrical portion 11a can elastically deform to expand radially, but elastic deformation in the direction of extension in the axial direction is restricted. Therefore, when a fluid such as compressed air is supplied to the inside of the cylindrical portion 11a, the expandable / contractible unit 11 operates to expand radially while contracting axially. Also, when the fluid is discharged from the inside of the cylindrical portion 11a, the expandable / contractible unit 11 contracts radially due to the elastic force of the cylindrical portion 11a and extends axially to return to its original shape. Each expandable / contractible unit 11 can be operated individually in a predetermined pattern.

[0021] The expandable / contractible unit 11 can have various configurations, such as a so-called McKibben type in which the outside of a cylindrical elastic body is covered with sleeve-shaped woven fibers, as long as it is configured to expand radially and contract axially when fluid is supplied.

[0022] Adjacent telescopic units 11 are connected to each other axially by a connecting portion 12. In this embodiment, the connecting portion 12 is a universal joint. As a result, the robot body 10 can bend at the portion of the connecting portion 12. Therefore, when the robot body 10 moves inside a pipe, even if the pipe is curved, it can move along the curved pipe because the space between adjacent telescopic units 11 bends at the connecting portion 12.

[0023] In this embodiment, a universal joint is used as the connecting portion 12, but it is not limited to this as long as it connects adjacent telescopic units 11 in a foldable manner.

[0024] A control unit 14 is connected to the robot body 10 via piping 13. The control unit 14 can individually supply fluid in a predetermined pattern to the inside of the cylindrical portion 11a of each telescopic unit 11 via piping 13. As the control unit 14 supplies fluid in a predetermined pattern to the inside of the cylindrical portion 11a of each telescopic unit 11, the multiple telescopic units 11 move in a predetermined pattern, allowing the robot body 10 to move inside the pipe.

[0025] Figure 2 shows an example of the peristaltic motion pattern of the multiple telescopic units 11 when the robot body 10 moves axially to one side inside the pipe 2, that is, when it moves forward to the left in Figure 2.

[0026] First, as shown in Figure 2(a), the leftmost (front) telescopic unit 11 and the second telescopic unit 11 from the left in Figure 2 are expanded radially while contracting axially. The two radially expanded telescopic units 11 each come into contact with the inner surface of the pipe 2 over their entire circumference. As a result, the robot body 10 is held axially by the two radially expanded telescopic units 11.

[0027] Next, from the state shown in Figure 2(a), as shown in Figure 2(b), the leftmost telescopic unit 11 is returned to its original shape, while the third telescopic unit 11 from the left is expanded radially and contracted axially. At this time, the second telescopic unit 11 from the left is in contact with the inner surface of the pipe 2, maintaining its axial position. As the leftmost telescopic unit 11 contracts radially and expands axially to return to its original shape, the left end (front end) of the robot body 10 moves to the left from the position shown in Figure 2(a). Also, as the third telescopic unit 11 from the left expands radially and contracts axially while the second telescopic unit 11 from the left is in contact with the inner surface of the pipe 2 and maintaining its axial position, the right end (rear end) of the robot body 10 also moves to the left from the position shown in Figure 2(a).

[0028] Next, from the state shown in Figure 2(b), as shown in Figure 2(c), the second telescopic unit 11 from the left is returned to its original shape, while the fourth telescopic unit 11 from the left is expanded radially and contracted axially. At this time, since the third telescopic unit 11 from the left is in contact with the inner circumferential surface of the pipe 2 and its axial position is maintained, as the second telescopic unit 11 from the left contracts radially and expands axially to return to its original shape, the left end (front end) of the robot body 10 moves further to the left from the position shown in Figure 2(b). Also, since the fourth telescopic unit 11 from the left expands radially and contracts axially while the third telescopic unit 11 from the left is in contact with the inner circumferential surface of the pipe 2 and its axial position is maintained, the right end (rear end) of the robot body 10 also moves further to the left from the position shown in Figure 2(b).

[0029] The same procedure is then used to operate the telescopic units 11 in the above pattern until the rightmost telescopic unit 11 is reached. Once the pattern reaches the rightmost telescopic unit 11, the process returns to the beginning and the telescopic units 11 are operated in the above pattern, as shown in Figure 2(d).

[0030] In this way, by making the multiple telescopic units 11 perform a peristaltic motion in the pattern described above, the robot body 10 can move forward inside the pipe 2 toward the left in Figure 2. Conversely, by operating the multiple telescopic units 11 in a pattern opposite to that shown in Figure 2, the robot body 10 can move backward inside the pipe 2 toward the right in Figure 2. In other words, the pipe-mobilizing robot 1 can move forward and backward inside the pipe 2 by having the robot body 10 perform the above movements.

[0031] The peristaltic motion patterns of the multiple retractable units 11 in the robot body 10 are not limited to those described above; other patterns are also acceptable as long as they allow the robot body 10 or the pipe-mobile robot 1 to move forward and backward.

[0032] As shown in Figure 1, in this embodiment, the robot body 10 is provided with a plurality of brushes 15 spaced apart in the axial direction of the robot body 10. More specifically, a brush 15 is provided at both ends in the axial direction of each telescopic unit 11. Each of the plurality of brushes 15 has a substantially annular shape centered on the axis O of the robot body 10. That is, each of the plurality of brushes 15 has a configuration in which a large number of bristles protruding radially outward from the outer circumferential surface of the robot body 10, centered on the axis O, are arranged around the entire circumference in the circumferential direction of the axis O. The large number of bristles constituting the brush 15 are made of a flexible and elastically deformable material, such as synthetic resin. The outer diameter of the brush 15 is substantially the same as the inner diameter of the pipe 2 to which the pipe-in-mobile robot 1 moves. Preferably, the outer diameter of the brush 15 is the same as or slightly larger than the inner diameter of the pipe 2 to which the pipe-in-mobile robot 1 moves. When the pipe-in-mobile robot 1 moves inside the pipe 2, the brush 15 comes into contact with the inner circumferential surface of the pipe 2 at its outer circumferential end.

[0033] The robot body 10 is equipped with multiple brushes 15, allowing it to move along the inside of the pipe 2 while being supported approximately in the center of the pipe 2 by the multiple brushes 15. Furthermore, the robot body 10 is equipped with multiple brushes 15, allowing it to clean the inside of the pipe 2 by collecting foreign matter (dirt) such as debris attached to the inner surface of the pipe 2 with the brushes 15 as it moves inside the pipe 2.

[0034] In this embodiment, the robot body 10 is provided with multiple brushes 15, but it is not limited to brushes 15. Other members, such as flange-shaped or umbrella-shaped synthetic rubber, may be provided as long as they have a substantially annular shape centered on the axis O of the robot body 10. Alternatively, the robot body 10 may be configured without multiple brushes 15 or other members having a substantially annular shape centered on the axis O of the robot body 10.

[0035] As shown in Figures 1 and 3, the tip posture maintenance section 20, the angle regulating joint section 30, and the elastic connection section 40 are located on the side of the robot body 10 that moves forward (left side in Figure 3).

[0036] As shown in Figure 3, the tip posture maintenance unit 20 has a tip body unit 21 and a pair of elastic bodies 22 and 23.

[0037] The tip body portion 21 is the part that constitutes the tip (front end) on the side of the pipe-in-pipe mobile robot 1 in the direction of forward movement. That is, the pipe-in-pipe mobile robot 1 moves forward inside the pipe 2 with the tip body portion 21 at the front. The tip body portion 21 has a cylindrical body portion 21a centered on axis O and a dome-shaped projection portion 21b centered on axis O that is connected to the end of the body portion 21a on the side in the direction of forward movement, and the overall shape is tapered. However, the shape of the tip body portion 21 is not limited to the shape described above.

[0038] The pair of elastic bodies 22 and 23 are each configured as an annular shape with a roughly circular or polygonal outer circumference centered on axis O, protruding radially outward from the outer surface of the body portion 21a of the tip body portion 21, and are spaced apart from each other in the axial direction. In this embodiment, the pair of elastic bodies 22 and 23 are each annular (annular with a circular outer circumference) centered on axis O. The front elastic body 22 is positioned at the front end portion of the body portion 21a of the tip body portion 21, and the rear elastic body 23 is positioned on the body portion 21a at a predetermined distance to the rear of the front elastic body 22. The axial distance between the pair of elastic bodies 22 and 23 can be appropriately set according to the size of the pipe to be moved, the curvature of the bent portion, etc. The pair of elastic bodies 22 and 23 are each elastically deformable in the axial direction and in the radial direction centered on axis O.

[0039] In this embodiment, the front elastic body 22 and the rear elastic body 23 have the same shape or configuration as each other. More specifically, the pair of elastic bodies 22 and 23 are each annular brushes centered on the axis O of the body portion 21a. That is, the pair of elastic bodies 22 and 23 are configured such that numerous bristles protrude radially outward from the outer circumferential surface of the body portion 21a, centered on the axis O, and are arranged around the entire circumference in the circumferential direction around the axis O. The numerous bristles constituting the elastic bodies 22 and 23 are made of a flexible and elastically deformable material, such as synthetic resin. The outer diameter of the elastic bodies 22 and 23 is approximately the same as the inner diameter of the pipe 2 to which the pipe-in-mobile robot 1 moves. Preferably, the outer diameter of the elastic bodies 22 and 23 is the same as or slightly larger than the inner diameter of the pipe 2 to which the pipe-in-mobile robot 1 moves. When the pipe-in-mobile robot 1 moves inside the pipe 2, the elastic bodies 22 and 23 come into contact with the inner circumferential surface of the pipe 2 at their outer ends.

[0040] The tip posture maintenance unit 20 has a pair of elastic bodies 22 and 23 provided on the tip body 21 at an axial distance from each other, so that when it moves inside the pipe 2, it can move along the pipe 2 while being supported by the pair of elastic bodies 22 and 23 at approximately the center of the pipe 2. Furthermore, if brushes are used as the pair of elastic bodies 22 and 23 provided on the tip body 21 of the tip posture maintenance unit 20, when it moves inside the pipe 2, the pair of elastic bodies 22 and 23 can collect foreign matter (dirt) such as debris attached to the inner surface of the pipe 2 and clean the inside of the pipe 2.

[0041] In this embodiment, the pair of elastic bodies 22 and 23 are annular in shape with respect to the axis O, but are not limited to this. As long as the tip posture maintenance portion 20 can be supported approximately in the center of the pipe 2, they may be configured as a roughly annular shape, such as a D shape with a small portion of the outer circumference cut off, or as an annular shape with a regular polygonal outer circumference. Furthermore, in this embodiment, brushes are used as the pair of elastic bodies 22 and 23, but are not limited to this. Any annular, elastically deformable member, such as a flange-shaped or umbrella-shaped synthetic rubber member, may be provided, as long as it has an annular shape with respect to the axis O of the tip body portion 21.

[0042] Preferably, the tip posture maintenance section 20 is configured such that the protruding portion 21b of the tip body section 21, which protrudes forward from the pair of elastic bodies 22 and 23, is contained within a virtual sphere 24 (shown by a dashed line in Figure 3) in which the outer peripheral ends 22a and 23a of the pair of elastic bodies 22 and 23 are inscribed over their entire circumference. The virtual sphere 24 is a sphere whose center point is a point 24a on the axis O at the central position between the pair of elastic bodies 22 and 23, which are spaced apart along the axis O, and inscribed with the outer peripheral ends 22a and 23a of the pair of elastic bodies 22 and 23. The protruding portion 21b of the tip body section 21 is entirely located inside the virtual sphere 24 without protruding outside of it.

[0043] In this embodiment, the tip posture maintenance unit 20 has a camera 25 mounted on the axis O of a protruding portion 21b that protrudes forward from the pair of elastic bodies 22 and 23 of the tip body 21. More specifically, the protruding portion 21b is configured as a transparent dome-shaped cover, and the camera 25 is installed on the axis O inside it. The camera 25 is oriented forward, and when the pipe-in-pipe mobile robot 1 moves inside the pipe 2, it can photograph the inside of the pipe 2 on the front side of the tip body 21. The camera 25 can be configured to display the captured image of the inside of the pipe 2 on a monitor placed outside the pipe 2, for example. By providing such a camera 25, the pipe-in-pipe mobile robot 1 can check the state inside the pipe 2 using the image captured by the camera 25 when moving inside the pipe 2.

[0044] Alternatively, a lighting device 26 may be installed inside the protruding portion 21b, so that the inside of the tube 2, which is being photographed by the camera 25, is illuminated by the light emitted by the lighting device 26. For example, an LED light can be used as the lighting device 26.

[0045] The angle-regulating joint 30 is provided between the tip attitude maintenance unit 20 and the robot body 10. More specifically, the angle-regulating joint 30 is provided between the elastic connection unit 40, which is connected to the rear end of the tip attitude maintenance unit 20, and the robot body 10. The angle-regulating joint 30 connects the tip attitude maintenance unit 20 so that it can be bent at an angle of less than 90 degrees relative to the robot body 10.

[0046] In this embodiment, the angle-regulating joint portion 30 has a universal joint portion 31 and a stopper portion 32.

[0047] The universal joint section 31 is a so-called universal joint. The universal joint section 31 is provided between the front fixing section 33 fixed to the rear end of the elastic connection section 40 and the rear fixing section 34 fixed to the front end of the robot body 10, and connects the front fixing section 33 and the rear fixing section 34 so that they can rotate freely around a front rotation axis 35 perpendicular to the axis O, and also so that they can rotate freely around a rear rotation axis 36 perpendicular to the axis O and the front rotation axis 35.

[0048] The stopper portion 32 is supported by the universal joint portion 31 and is provided between the front fixing portion 33 and the rear fixing portion 34. The stopper portion 32 is configured to contact the front fixing portion 33 when the front fixing portion 33 rotates by a predetermined angle of less than 90 degrees around the front rotation axis 35 relative to the axis O. As a result, the rotation angle of the front fixing portion 33 around the front rotation axis 35 with respect to the axis O, i.e., the bending angle, is restricted to less than 90 degrees by the stopper portion 32. The stopper portion 32 is also configured to contact the rear fixing portion 34 when the rear fixing portion 34 rotates by a predetermined angle of less than 90 degrees around the rear rotation axis 36 relative to the axis O. As a result, the rotation angle of the rear fixing portion 34 around the rear rotation axis 36 with respect to the axis O, i.e., the bending angle, is restricted to less than 90 degrees by the stopper portion 32.

[0049] The angle-regulating joint 30 is provided between the tip posture maintenance unit 20 and the robot body 10 and connects them in such a way that the tip posture maintenance unit 20 can be bent at an angle of less than 90 degrees relative to the robot body 10. The configuration is not limited to the one with the universal joint 31 and stopper 32 described above, but can be configured in various ways. Furthermore, the angle-regulating joint 30 may be omitted.

[0050] The elastic connection part 40 is provided between the tip posture maintenance part 20 and the angle regulating joint part 30, connecting the tip posture maintenance part 20 and the angle regulating joint part 30. If the angle regulating joint part 30 is not provided, the elastic connection part 40 is provided between the tip posture maintenance part 20 and the robot body 10, connecting the tip posture maintenance part 20 and the robot body 10.

[0051] In this embodiment, the elastic connection portion 40 is composed of a compression coil spring extending along the axis O. The elastic connection portion 40 can be elastically deformed to contract along the axis O. Furthermore, the elastic connection portion 40 can be flexibly elastically deformed to curve relative to the axis O. Therefore, when the tip attitude maintenance portion 20 reaches the bent portion 2b of the pipe 2, the elastic connection portion 40 elastically deforms to curve relative to the axis O, allowing it to bend relative to the angle-regulating joint portion 30 in a direction along the bent portion 2b.

[0052] The elastic connecting portion 40 is not limited to the compression coil spring described above, but may be any other material, such as a rubber tube, that is provided between the tip attitude maintenance portion 20 and the angle regulating joint portion 30 to connect them and is elastically deformable to curve with respect to the axis O between the tip attitude maintenance portion 20 and the angle regulating joint portion 30.

[0053] As shown in Figure 4, the pipe-in-pipe mobile robot 1 according to this embodiment can reliably pass through a bent section 2b even if the pipe 2 to which the pipe-in-pipe mobile robot 1 moves has a bent section 2b between a pair of straight sections 2a.

[0054] In other words, in the pipe-in-robot 1 according to this embodiment, a pair of elastic bodies 22 and 23 are provided on the tip body portion 21 of the tip attitude maintenance portion 20, which is connected to the robot body 10 via the elastic connection portion 40 and the angle-regulating joint portion 30 and constitutes the tip of the pipe-in-robot 1, with a gap in the axial direction between them. For example, even if there is a step 2c (see Figure 4) at the connection point between the straight portion 2a and the bent portion 2b of the pipe 2, the tip body portion 21 can be moved along the bent portion 2b to make it less likely to get caught on the step 2c, thereby suppressing the tip body portion 21 from getting caught on the bent portion 2b of the pipe 2.

[0055] More specifically, as shown in Figure 5(a), when the tip body 21 of the tip posture maintenance unit 20 moves along the straight portion 2a of the pipe 2, the pair of elastic bodies 22 and 23 each come into contact with the inner circumferential surface of the straight portion 2a of the pipe 2, so that the tip body 21 moves inside the pipe 2 while maintaining its axis O in a position parallel to the extending direction of the straight portion 2a of the pipe 2. As shown in Figure 5(b), when the tip posture maintenance unit 20 moves forward and the tip body 21 reaches the bent portion 2b from the straight portion 2a of the pipe 2, the front elastic body 22 comes into contact with the inner circumferential surface of the bent portion 2b of the pipe 2, and the rear elastic body 23 comes into contact with the inner circumferential surface of the straight portion 2a of the pipe 2, so that the tip body 21 rotates around point 24a and begins to bend along the bent portion 2b. At this time, the elastic connection portion 40 is compressed and elastically deformed between the tip body portion 21 and the angle-regulating joint portion 30, allowing rotation of the tip body portion 21 relative to the angle-regulating joint portion 30. As shown in Figure 5(c), when the tip posture maintenance portion 20 moves further forward and the rear elastic body 23 reaches the bent portion 2b, the tip posture maintenance portion 20 moves along the bent portion 2b inside the pipe 2 while rotating around point 24a, as shown in Figure 5(d), because the pair of elastic bodies 22 and 23 each come into contact with the inner circumferential surface of the bent portion 2b of the pipe 2. As shown in Figure 5(e), when the tip attitude maintenance unit 20 moves further forward and the front elastic body 22 passes the bent portion 2b and reaches the straight portion 2a, the tip attitude maintenance unit 20 is gradually returned to a position along the straight portion 2a as the front elastic body 22 comes into contact with the inner circumferential surface of the straight portion 2a of the pipe 2 and the rear elastic body 23 comes into contact with the inner circumferential surface of the bent portion 2b of the pipe 2. Then, as shown in Figure 5(f), when the tip attitude maintenance unit 20 moves further forward and the rear elastic body 23 reaches the straight portion 2a, the pair of elastic bodies 22 and 23 come into contact with the inner circumferential surface of the straight portion 2a of the pipe 2, respectively, and the tip attitude maintenance unit 20 moves inside the pipe 2 while maintaining its axis O in a position parallel to the extending direction of the straight portion 2a of the pipe 2.

[0056] As described above, in the pipe-in-robot robot 1 according to this embodiment, a pair of elastic bodies 22 and 23 are provided on the tip body portion 21 of the tip attitude maintenance portion 20, which is connected to the robot body 10 via the elastic connection portion 40 and the angle-regulating joint portion 30 and constitutes the tip of the pipe-in-robot robot 1. These elastic bodies 22 and 23 are spaced apart in the axial direction, and when the pipe-in-robot robot 1 moves inside the pipe 2, the pair of elastic bodies 22 and 23 each come into contact with the inner circumferential surface of the pipe 2, thereby guiding the tip body portion 21 in a posture along the pipe 2. As a result, the tip body portion 21 can smoothly pass through the bent portion 2b of the pipe 2. Furthermore, in the pipe-moving robot 1 according to this embodiment, as described above, the pair of elastic bodies 22 and 23 each contact the inner circumferential surface of the pipe 2, so that the tip body portion 21 is guided in a position along the pipe 2. This prevents the tip body portion 21 from getting caught on the bent portion 2b of the pipe 2, and the elastic connecting portion 40 from elastically deforming so that it curves in the opposite direction to the bent portion 2b, thereby suppressing blockage of the tip body portion 21 in the bent portion 2b of the pipe 2.

[0057] Furthermore, in the pipe-mobile robot 1 according to this embodiment, if the pair of elastic bodies 22 and 23 are used as brushes, the tip body 21 smoothly passes through the bent portion 2b of the pipe 2, allowing the pair of elastic bodies 22 and 23 provided on the tip body 21 to effectively clean both the outer and inner surfaces of the bent portion 2b of the pipe 2. Also, if a camera 25 is provided on the protruding portion 21b, the axis of the camera 25 can be stabilized in a certain direction, allowing the camera 25 to capture the entire area of ​​the object to be photographed inside the bent portion 2b of the pipe 2.

[0058] Furthermore, in the pipe-moving robot 1 according to this embodiment, the tip body 21 can smoothly pass through the bent portion 2b of the pipe 2. Therefore, after the tip body 21 gets caught on the step 2c between the straight portion 2a and the bent portion 2b of the pipe 2, compressing the elastic connecting portion 40, the catch on the step 2c of the tip body 21 is released, which suppresses the phenomenon in which the tip body 21 moves forcefully through the bent portion 2b due to the spring force of the elastic connecting portion 40. In other words, the tip body 21 can smoothly pass through the bent portion 2b of the pipe 2 at a predetermined moving speed. As a result, if the pair of elastic bodies 22 and 23 are used as brushes, the pair of elastic bodies 22 and 23 provided on the tip body 21 can more effectively clean the inner surfaces of both the outer and inner circumferences of the bent portion 2b of the pipe 2. Also, if a camera 25 is provided on the protruding portion 21b, the camera 25 can capture images of the inside of the bent portion 2b of the pipe 2 without image skipping.

[0059] Furthermore, in the pipe-mobile robot 1 according to this embodiment, the protruding portion 21b of the tip body portion 21 that protrudes forward from the pair of elastic bodies 22 and 23 is contained within the range of a virtual spherical surface 24 inscribed over the entire circumference of the outer peripheral ends of the pair of elastic bodies 22 and 23, thereby making it even less likely for the tip body portion 21 to get caught on the bent portion 2b or step 2c of the pipe 2.

[0060] In other words, as shown in Figure 5, the tip body portion 21 rotates around point 24a, which is the center of the virtual sphere 24, when moving along the bent portion 2b of the pipe 2. By ensuring that the protruding portion 21b is contained within the range of the virtual sphere 24, the protruding portion 21 is less likely to come into contact with the inner surface of the bent portion 2b of the pipe 2 when the tip body portion 21 moves along the bent portion 2b of the pipe 2. This further effectively suppresses the protruding portion 21 of the tip body portion 21 from strongly contacting the inner surface of the bent portion 2b of the pipe 2 or getting caught on the step 2c between the straight portion 2a and the bent portion 2b. Therefore, the tip body portion 21 can pass through the bent portion 2b of the pipe 2 more smoothly.

[0061] Furthermore, in the pipe-moving robot 1 according to this embodiment, the protruding portion 21b that extends forward from the pair of elastic bodies 22 and 23 of the tip body 21 is kept within the range of a virtual spherical surface 24 inscribed by the outer peripheral ends 22a and 23a of the pair of elastic bodies 22 and 23 over its entire circumference. As a result, when the tip body 21 moves along the bent portion 2b of the pipe 2, it is possible to suppress the protruding portion 21b from being rubbed against the inner surface of the bent portion 2b and getting scratched. This allows the camera 25 to take clearer images of the inside of the pipe 2 through the transparent protruding portion 21b when the camera 25 is installed inside the transparent protruding portion 21b.

[0062] In the pipe-moving robot 1 according to this embodiment, the rear elastic body 23 can be made more flexible than the front elastic body 22. That is, the rear elastic body 23 can be configured to easily elastically deform in the axial direction with less force than the front elastic body 22. As shown in Figures 5(c) and 5(d), when the tip body 21 moves along the bent portion 2b of the pipe 2, the rear elastic body 23 may come into contact more strongly with the inner surface of the bent portion 2b than the front elastic body 22. However, by making the rear elastic body 23 more flexible than the front elastic body 22, it is possible to suppress the rear elastic body 23 from getting caught on the inner surface of the bent portion 2b. In particular... When the bent portion 2b of the pipe 2 is an injection-molded resin product, protrusions such as burrs generated during molding may be formed on the inner surface of the inner circumference of the bent portion 2b of the pipe 2. However, even in such cases, by making the rear elastic body 23 more flexible than the front elastic body 22, it is possible to prevent the rear elastic body 23 from getting caught on the protrusions on the inner surface of the inner circumference of the bent portion 2b. Therefore, the tip body portion 21 can pass through the bent portion 2b of the pipe 2 more smoothly.

[0063] Furthermore, in the pipe-mobile robot 1 according to this embodiment, an angle-regulating joint 30 is provided between the tip body 21 and the robot body 10 in addition to the elastic connection 40. This makes it less likely for the front end of the robot body 10 to get caught on the step 2c or protrusion of the bent portion 2b of the pipe 2 after or while the tip body 21 has passed through. In other words, in conventional designs, even if the tip can pass over the step, there is a risk that the front end of the robot body may get caught on the step, preventing the pipe-mobile robot from moving forward. However, in the pipe-mobile robot 1 according to this embodiment, this problem can be suppressed by having an angle-regulating joint 30 in addition to the elastic connection 40 between the tip body 21 and the robot body 10.

[0064] More specifically, as shown in Figure 6, after the tip body 21 passes through the bent portion 2b of the pipe 2, the angle-regulating joint 30 bends along the bent portion 2b in addition to the elastic connection portion 40 between the tip body 21 and the robot body 10, allowing the pipe-moving robot 1 to move smoothly inside the bent portion 2b between the tip body 21 and the robot body 10. At this time, the angle-regulating joint 30 is configured such that the stopper portion 32 abuts against the front fixing portion 33, restricting the bending angle of the tip body 21 relative to the robot body 10 to an angle of less than 90 degrees. This prevents the angle-regulating joint 30 from bending to an excessive angle of 90 degrees or more and buckling inside the bent portion 2b. As a result, as shown in Figure 7, after the tip body 21 passes through the bent portion 2b, the angle-regulating joint 30 can be pushed into the straight portion 2a without getting caught on the step 2c. Therefore, after the tip body portion 21 passes through the bent portion 2b, the angle-regulating joint portion 30 and the robot body 10 can also smoothly pass through the bent portion 2b.

[0065] Next, a pipe-in-mobile robot 100 according to the second embodiment of the present invention will be described based on Figures 8, 9, and 10. In Figures 8, 9, and 10, the same reference numerals are used for members or parts corresponding to those described above. Furthermore, in the pipe-in-mobile robot 100 according to the second embodiment, the configuration of the robot body 10, the tip attitude maintenance unit 20, the angle regulating joint unit 30, and the elastic connection unit 40 is basically the same as that of the pipe-in-mobile robot 1 according to the first embodiment, so a further explanation will be omitted.

[0066] As shown in Figure 8, the pipe-mounted mobile robot 100 according to the second embodiment differs from the pipe-mounted mobile robot 1 according to the first embodiment in that it has a cover 50 that covers the angle-regulating joint portion 30.

[0067] As shown in Figure 9, the cover 50 has a double structure comprising an inner cylindrical body 51 and an outer cylindrical body 52. ​​The inner cylindrical body 51 is formed from an expandable material into a cylindrical shape centered on axis O, and is arranged coaxially with the angle-regulating joint 30, covering the entire outside of the angle-regulating joint 30. The outer cylindrical body 52 is formed from an expandable material into a cylindrical shape that is larger in diameter than the inner cylindrical body 51 and coaxial with the inner cylindrical body 51, and is arranged on top of the outside of the inner cylindrical body 51, covering the entire outside of the inner cylindrical body 51. The outer cylindrical body 52 may be arranged in contact with the inner cylindrical body 51, or it may be arranged with a gap between it and the inner cylindrical body 51. The cover 50 is fixed to the angle-regulating joint 30 using retaining members 53 and 54 at the folded-over portions at both ends of the inner cylindrical body 51 and the outer cylindrical body 52. ​​Inclined surfaces 53a and 54a are provided between the outer circumferential surface and the side surface of the retaining members 53 and 54.

[0068] The configuration for fixing the cover 50 to the angle-regulating joint 30 can be modified as appropriate, for example, by directly fixing the ends of the inner cylindrical body 51 and the outer cylindrical body 52 to the front fixing part 33 and the rear fixing part 34 using cable ties.

[0069] In this embodiment, the inner cylindrical body 51 and the outer cylindrical body 52 are each made of a cloth (fabric) woven from nylon fibers in a predetermined pattern, and are expandable and contractible in the axial direction and radial direction around axis O, respectively. Since the inner cylindrical body 51 and the outer cylindrical body 52 are each made of a nylon cloth with relatively low frictional resistance, the frictional resistance between the inner cylindrical body 51 and the outer cylindrical body 52 is smaller than the frictional resistance between the inner cylindrical body 51 and the angle-regulating joint 30 and the frictional resistance between the outer cylindrical body 52 and the inner surface of the pipe 2. In this way, the cover 50 is configured such that the frictional resistance between the inner cylindrical body 51 and the outer cylindrical body 52 is smaller than the frictional resistance between the outer cylindrical body 52 and the inner surface of the pipe 2. Furthermore, the cover 50 may be made of other fabrics or sheets, not limited to a cloth woven from nylon fibers in a predetermined pattern, as long as the frictional resistance between the inner cylindrical body 51 and the outer cylindrical body 52 is smaller than the frictional resistance between the outer cylindrical body 52 and the inner surface of the tube 2.

[0070] As shown in Figure 10, when the pipe-mounted mobile robot 100 according to the second embodiment passes through the bent portion 2b of the pipe 2, the angle-regulating joint 30 moves forward in a bent state, causing the cover 50 covering the angle-regulating joint 30 to be strongly pressed against the inner surface on the outer circumference side of the pipe 2. At this time, since the cover 50 has a double structure comprising an inner cylindrical body 51 and an outer cylindrical body 52, even if the outer cylindrical body 52 is strongly pressed against the inner surface on the outer circumference side of the pipe 2 and cannot slide forward on the inner surface of the pipe 2 due to frictional resistance between it and the inner surface, the outer cylindrical body 52 extends in the axial direction, and the inner cylindrical body 51, which is pushed by the angle-regulating joint 30 and pressed against the outer cylindrical body 52, slips relative to the outer cylindrical body 52, allowing the angle-regulating joint 30 to move forward slightly inside the pipe 2. Then, the driving force from this slight forward movement causes the outer cylindrical body 52 to slip in the forward direction relative to the inner surface of the pipe 2, allowing the pipe-mounted mobile robot 100 to move forward inside the pipe 2.

[0071] Thus, in the pipe-in-route robot 100 according to the second embodiment, a cover 50 is provided to cover the angle-regulating joint 30. Therefore, even if the angle-regulating joint 30 is strongly pressed against the inside of the pipe 2 when the pipe-in-route robot 100 passes through the bent portion 2b of the pipe 2, the pipe-in-route robot 100 can be reliably advanced.

[0072] Furthermore, by providing an inclined surface 53a on the front retaining member 53 for fixing the cover 50, the retaining member 53 can overcome the step 2c on the inclined surface 53a, thereby enabling the pipe-in-mobile robot 100 to move forward more reliably.

[0073] Next, a pipe-in-mobile robot 200 according to the third embodiment of the present invention will be described based on Figures 11 and 12. In Figures 10 and 11, the same reference numerals are used for members or parts corresponding to those described above. Furthermore, in the pipe-in-mobile robot 200 according to the third embodiment, the configuration of the robot body 10, the tip attitude maintenance unit 20, and the elastic connection unit 40 is basically the same as that of the pipe-in-mobile robot 1 according to the first embodiment, so a further explanation will be omitted.

[0074] As shown in Figure 11, the pipe-mounted mobile robot 200 according to the third embodiment differs from the pipe-mounted mobile robot 1 according to the first embodiment in that the angle-regulating joint portion 30 has a stopper position changing device 60 that changes the axial position of the stopper portion 32.

[0075] In this embodiment, the stopper position changing device 60 includes an air cylinder 61 and a connecting body 62 fixed to the rod 61a of the air cylinder 61. The connecting body 62 is connected to the stopper portion 32, and the stopper portion 32 moves integrally with the connecting body 62. By operating the air cylinder 61, the stopper position changing device 60 can change the position of the stopper portion 32 in stages to the position closest to the front fixing portion 33 shown in Figure 12(a), a position further from the front fixing portion 33 than the position closest to the front fixing portion 33 shown in Figure 12(b), and the position furthest from the front fixing portion 33 shown in Figure 12(c). In this way, by changing the position of the stopper portion 32 with the stopper position changing device 60, the distance between the stopper portion 32 and the front fixing portion 33 can be changed, and the bending angle of the angle regulating joint portion 30 can be changed to multiple angles of less than 90 degrees to match the shape of the bent portion 2b of the pipe 2.

[0076] Furthermore, the position of the stopper portion 32, which is changed by the stopper position changing device 60, is not limited to the three positions described above, but can be set as appropriate.

[0077] The stopper position changing device 60 can be configured such that the control device (not shown) determines the bending angle of the bent portion 2b based on the image of the inside of the pipe 2 taken by the camera 25, and based on the determination result, the control device automatically controls the operation of the air cylinder 61 so that the stopper portion 32 is in a position corresponding to the bent portion 2b of the pipe 2.

[0078] Alternatively, the stopper position changing device 60 may be configured to allow manual operation of the connecting body 62 so that the stopper portion 32 is positioned according to the bent portion 2b of the pipe 2, without using an air cylinder 61. In this case, the connecting body 62 can be manually operated before inserting the pipe-moving robot 1 into the pipe 2.

[0079] Next, a pipe-mounted mobile robot 300 according to the fourth embodiment of the present invention will be described based on Figures 13 and 14. In Figures 13 and 14, the same reference numerals are used for members or parts corresponding to those described above. Furthermore, in the pipe-mounted mobile robot 300 according to the fourth embodiment, the configuration of the robot body 10, angle-regulating joint 30, and elastic connection part 40 is basically the same as that of the pipe-mounted mobile robot 1 according to the first embodiment, so a further explanation will be omitted.

[0080] As shown in Figure 13, the pipe-in-mobile robot 300 according to the fourth embodiment differs from the pipe-in-mobile robot 1 according to the first embodiment in that the tip attitude maintenance unit 20 has an intermediate elastic body 27 between the front elastic body 22 and the rear elastic body 23, in addition to the front elastic body 22 and the rear elastic body 23. More specifically, in the pipe-in-mobile robot 300 according to the fourth embodiment, the front elastic body 22 is positioned at the front end of the tip body 21, the rear elastic body 23 is positioned at the rear end of the tip body 21, and an intermediate elastic body 27 is positioned between the front elastic body 22 and the rear elastic body 23, with a gap between them relative to both the front elastic body 22 and the rear elastic body 23. The outer diameter of the intermediate elastic body 27 is the same as that of the elastic bodies 22 and 23.

[0081] In the pipe-moving robot 300 according to the fourth embodiment, as shown in Figure 14(a), when the tip body 21 of the tip attitude maintenance unit 20 moves along the straight portion 2a of the pipe 2, the pair of elastic bodies 22, 23 and elastic body 27 each come into contact with the inner circumferential surface of the straight portion 2a of the pipe 2, so that the tip body 21 moves inside the pipe 2 while maintaining its axis O in a position parallel to the extending direction of the straight portion 2a of the pipe 2. As shown in Figure 14(b), when the tip attitude maintenance unit 20 moves forward and the tip body 21 reaches the bent portion 2b from the straight portion 2a of the pipe 2, the front elastic body 22 comes into contact with the inner circumferential surface of the bent portion 2b of the pipe 2, and the tip body 21 begins to bend along the bent portion 2b while rotating around point 24a. Then, as shown in Figures 14(c) and 14(d), as the tip posture maintenance unit 20 moves forward further, the intermediate elastic body 27 catches on the inner surface of the bent portion 2b of the pipe 2, promoting rotation of the tip body 21 around point 24a. As shown in Figure 14(e), as the tip posture maintenance unit 20 moves forward further and the front elastic body 22 passes the bent portion 2b and reaches the straight portion 2a, the intermediate elastic body 27 is released from its catch on the inner surface of the bent portion 2b, and the tip posture maintenance unit 20 is gradually returned to a position along the straight portion 2a as the front elastic body 22 comes into contact with the inner surface of the straight portion 2a of the pipe 2 and the rear elastic body 23 comes into contact with the inner surface of the bent portion 2b of the pipe 2. Then, as shown in Figure 14(f), when the tip attitude maintenance unit 20 moves further forward and the rear elastic body 23 reaches the straight portion 2a, the pair of elastic bodies 22, 23 and elastic body 27 come into contact with the inner circumferential surface of the straight portion 2a of the pipe 2, and the tip attitude maintenance unit 20 moves inside the pipe 2 while maintaining its axis O in a position parallel to the extending direction of the straight portion 2a of the pipe 2.

[0082] As described above, in the pipe-in-route robot 300 according to the fourth embodiment, the tip attitude maintenance unit 20 is configured to have an intermediate elastic body 27 between the front elastic body 22 and the rear elastic body 23, in addition to the front elastic body 22 and the rear elastic body 23. As a result, the tip attitude maintenance unit 20 can pass through the bent portion 2b more smoothly. This makes it possible for the pipe-in-route robot 300 to pass through the bent portion 2b of the pipe 2 more reliably.

[0083] In the pipe-in-route robot 300 according to the fourth embodiment, it is preferable that the front elastic body 22 and the rear elastic body 23 have the same rigidity or flexibility, while the intermediate elastic body 27 is configured to deform more flexibly than the front elastic body 22 and the rear elastic body 23. As a result, as shown in Figures 14(c) and 14(d), when the intermediate elastic body 27 catches on the inner surface of the inner circumference of the bent portion 2b of the pipe 2, the rotation of the tip body portion 21 around point 24a is promoted, allowing the intermediate elastic body 27 to reliably pass through the bent portion 2b, thereby enabling the pipe-in-route robot 300 to pass through the bent portion 2b more reliably.

[0084] The present invention is not limited to the embodiments described above, and it goes without saying that various modifications are possible without departing from the spirit of the invention.

[0085] For example, in the first embodiment, the tip body portion 21 of the tip posture maintenance portion 20 is configured to have a protruding portion 21b, but the tip body portion 21 does not necessarily have to be provided. [Explanation of Symbols]

[0086] 1. In-pipe mobile robot 2 tubes 2a Straight section 2b Bent part 2c step 10 Robot body 11 Extendable Unit 12 Connecting part 13 Piping 14 Control Unit 15 brushes 20 Tip posture maintenance part 21 Tip body 21a Torso 21b Projecting part 22 Elastic body 23 Elastic body 24 Virtual Sphere 24a points 25 Cameras 26 Lighting equipment 27 Elastic body 30 Angle-restricting joint 31 Universal joint section 32 Stopper part 33 Front fixation part 34 Rear fixed part 35 Forward pivot axis 36 Rear rotation axis 40 Elastic connection part 50 Covers 51 Inner cylinder 52 Outer tubular body 53 Retaining member 53a Slope 54 Retaining member 54a Slope 60 Stopper position changing device 61 Air Cylinder 61a Rod 62 connectors 100 In-pipe mobile robots 200 In-pipe mobile robots 300 In-pipe mobile robots O axis

Claims

1. A pipe-moving robot is provided, comprising a robot body with at least three expandable / contractible units, each of which expands radially and contracts axially when fluid is supplied, and configured to move inside a pipe by the peristaltic movement of the expandable / contractible units in a predetermined pattern, The tip of the in-pipe mobile robot comprises a tip body portion that constitutes the tip of the robot, and a tip attitude maintenance portion having a pair of elastic bodies, each of which is an annular shape roughly circular or has a regular polygonal outer circumference centered on the axis of the tip body portion, protruding radially outward from the outer surface of the tip body portion and arranged at a distance from each other in the axial direction. A pipe-mobile robot characterized by having an elastically deformable elastic connecting part provided between the tip posture maintenance part and the robot body.

2. The pipe-moving robot according to claim 1, further comprising an angle-regulating joint provided between the elastic connection portion and the robot body, which allows the tip attitude maintenance portion to be bent at an angle of less than 90 degrees relative to the robot body.

3. The pipe-in-machine robot according to claim 1 or 2, wherein the protruding portion of the tip body that protrudes forward from the pair of elastic bodies is contained within the range of a virtual spherical surface in which the outer peripheral ends of each of the pair of elastic bodies are inscribed over their entire circumference.

4. The pipe-in-route robot according to claim 1 or 2, wherein the rear elastic body is more flexible than the front elastic body.

5. The pipe-in-machine robot according to claim 1 or 2, wherein a camera is provided on the axis of a protruding portion that protrudes forward from the pair of elastic bodies of the tip body.

6. The pipe-moving robot according to claim 2, comprising an inner cylindrical body formed in a stretchable cylindrical shape and an outer cylindrical body formed in a stretchable cylindrical shape and arranged on top of the outer surface of the inner cylindrical body, wherein the robot has a cover configured such that the frictional resistance between the inner cylindrical body and the outer cylindrical body is smaller than the frictional resistance between the outer cylindrical body and the inner surface of the pipe, and the cover covers the angle-regulating joint portion.