Pipe cleaning robot

Abstract

A pipe cleaning robot (1) having a robot body (10) and a cleaning body (20) provided on the outer periphery of the robot body (10), the pipe cleaning robot (1) being characterized in that: a first reaction force generated when an outer peripheral end (20a) of the cleaning body (20) is subjected to an external force toward one side in the axial direction is configured to be greater than a second reaction force generated when the outer peripheral end (20a) of the cleaning body (20) is subjected to an external force toward the other side in the axial direction; the cleaning body (20) is configured from a brush; and a restricting body (21) is attached to one side in the axial direction of the cleaning body (20) of the robot body (10), which restricts the inclination of the cleaning body (20) toward one side in the axial direction.

Description

Pipe cleaning robot

[0001] The present invention relates to a pipe cleaning robot that cleans the inside of a pipe.

[0002] Office buildings, factories, detached houses, etc. are filled with thin, winding pipes, such as air ducts for air conditioners. In order to clean the inside of such pipes, pipe cleaning robots that can move around and clean the inside of the pipes have been developed.

[0003] For example, Patent Document 1 describes an in-pipe cleaning robot having a robot body with six telescopic units that expand radially and contract axially when fluid is supplied to each of them, and a brush-like cleaning body that protrudes radially outward from the outer periphery of the robot body, and is configured so that the six telescopic units perform peristaltic motion in a predetermined pattern, causing the robot body to move inside the pipe and clean the inside of the pipe with the cleaning body.

[0004] Japanese Patent Application Laid-Open No. 2018-69125

[0005] However, the conventional pipe cleaning robots described above sometimes fail to sufficiently clean the dirt inside the pipes.

[0006] The present invention has been made in consideration of these problems, and its purpose is to provide a pipe cleaning robot that can clean dirt inside pipes that cannot be cleaned by conventional pipe cleaning robots.

[0007] The pipe cleaning robot of the present invention comprises a robot main body having at least three extendable units that expand radially and contract axially when fluid is supplied thereto, and a cleaning body that protrudes radially outward from the outer periphery of the robot main body, and is configured such that the extendable units perform peristaltic movement in a predetermined pattern, causing the robot main body to move inside the pipe and clean the inside of the pipe with the cleaning body, wherein a first reaction force generated when the outer peripheral end of the cleaning body is subjected to an external force toward one side in the axial direction is greater than a second reaction force generated when the outer peripheral end of the cleaning body is subjected to an external force toward the other side in the axial direction, the cleaning body being a brush, and a regulating body attached to the robot main body in the axial direction is disposed on one side of the cleaning body and that comes into contact with the cleaning body to regulate tilt of the cleaning body to one side in the axial direction when the outer peripheral end of the cleaning body is subjected to an external force toward one side in the axial direction while the cleaning body is in contact with the inner surface of the pipe.

[0008] In the pipe cleaning robot of the present invention having the above configuration, it is preferable that a plurality of the cleaning bodies are provided on the robot body at intervals in the axial direction.

[0009] In the above-described configuration, the pipe cleaning robot of the present invention is preferably configured such that, of the pair of cleaning bodies adjacent in the axial direction, a first reaction force generated when the outer peripheral end of the cleaning body on one side in the axial direction is subjected to an external force toward that side in the axial direction is greater than a first reaction force generated when the outer peripheral end of the cleaning body on the other side in the axial direction is subjected to an external force toward that side in the axial direction.

[0010] According to the present invention, it is possible to provide an in-pipe cleaning robot that can clean dirt inside pipes that cannot be cleaned by conventional in-pipe cleaning robots.

[0011] 1 is a perspective view of a pipe cleaning robot according to a first embodiment of the present invention; FIG. 2 is a diagram illustrating the operating pattern of the extendable unit during the peristaltic movement of the robot main body; (a) is a perspective view schematically illustrating a part of the pipe cleaning robot according to the first embodiment in which a cleaning body is provided, and (b) is a cross-sectional view taken along the axis of the part of the pipe cleaning robot according to the first embodiment in which a cleaning body is provided (the cross-section of the robot main body is omitted); (a) is a cross-sectional view showing the state of the cleaning body when it is moving toward one axial side inside the pipe, and (b) is a cross-sectional view showing the state of the cleaning body when it is moving toward the other axial side inside the pipe, of the pipe cleaning robot according to the first embodiment; (a) is a cross-sectional view showing the state of the cleaning body when it is moving toward one axial side inside the pipe, and (b) is a cross-sectional view showing the state of the cleaning body when it is moving toward the other axial side inside the pipe, of the pipe cleaning robot according to a modified example in which the reaction forces of the three cleaning bodies are different, and (b) is a cross-sectional view showing the state of the cleaning body when it is moving toward one axial side inside the pipe, of the pipe cleaning robot according to the modified example; 1A is a cross-sectional view of a pipe cleaning robot according to another modified example, showing the state of the cleaning element as it moves inside a pipe toward one axial side, and FIG. 1B is a cross-sectional view of the cleaning element as it moves inside the pipe toward the other axial side. FIG. 1C is a perspective view schematically showing a portion of a pipe cleaning robot according to a second embodiment of the present invention, in which a cleaning element is provided. FIG. 1A is a cross-sectional view of a pipe cleaning robot according to the second embodiment, showing the state of the cleaning element as it moves inside a pipe toward one axial side, and FIG. 1B is a cross-sectional view of the cleaning element as it moves inside the pipe toward the other axial side. FIG. 1C is a cross-sectional view of a pipe cleaning robot according to a third embodiment of the present invention, showing the state of the cleaning element as it moves inside a pipe toward one axial side, and FIG. 1B is a cross-sectional view of the cleaning element as it moves inside the pipe toward the other axial side. FIG. 1C is a cross-sectional view of a pipe cleaning robot according to a modified example, showing the state of the cleaning element as it moves inside a pipe toward one axial side, and FIG. 1B is a cross-sectional view of the cleaning element as it moves inside the pipe toward the other axial side.

[0012] Hereinafter, the pipe cleaning robot of the present invention will be described in detail with reference to the drawings.

[0013] The pipe cleaning robot 1 according to the first embodiment of the present invention shown in FIG. 1 moves and cleans the inside of thin, winding pipes such as air ducts for air conditioners installed in office buildings, factories, detached houses, etc.

[0014] The pipe cleaning robot 1 has a robot body 10 and a cleaning body 20.

[0015] The robot body 10 is also called an earthworm-type robot, a peristaltic robot, or the like, and has an elongated shape extending along an axis O. The robot body 10 can move inside the pipe to one side and the other side in the axial direction. That is, the robot body 10 can move forward and backward inside the pipe. The axial direction is the direction along the axis O of the robot body 10, i.e., the longitudinal direction.

[0016] The robot body 10 is equipped with at least three extension units 11 as a drive source for moving inside the pipe. In this embodiment, the robot body 10 is equipped with seven extension units 11 (only four extension units 11 are shown in FIG. 1). Note that the number of extension units 11 can be changed as needed as long as the robot body 10 is equipped with at least three extension units 11.

[0017] The telescopic unit 11 is also called an artificial muscle. The telescopic unit 11 includes a tubular portion 11a formed of an elastic material such as rubber into a cylindrical shape centered on an axis O. Both axial ends of the tubular portion 11a are closed. Multiple fiber bundles (not shown) with high tensile strength are arranged axially inside the tubular portion 11a. This allows the tubular portion 11a to elastically deform so as to expand radially, but restricts elastic deformation in the axial direction. Therefore, when a fluid such as compressed air is supplied to the inside of the tubular portion 11a, the telescopic unit 11 operates by expanding radially and contracting axially. Furthermore, when the fluid is discharged from the inside of the tubular portion 11a, the telescopic unit 11 contracts radially due to the elastic force of the tubular portion 11a and expands axially, returning to its original shape. Each telescopic unit 11 can be independently operated in a predetermined pattern.

[0018] The telescopic unit 11 may have various configurations, such as a so-called McKibben type in which the outside of a cylindrical elastic body is covered with fibers woven into a sleeve shape, as long as it is configured to expand radially and contract axially when fluid is supplied.

[0019] Adjacent telescopic units 11 are axially connected to each other by connecting portions 12. In this embodiment, connecting portions 12 are universal joints. This allows the robot body 10 to bend at the connecting portions 12. Therefore, when moving inside a pipe, even if the pipe is bent, the robot body 10 can bend at the connecting portions 12 and move along the curved pipe, allowing the pipe cleaning robot 1 to move along the curved pipe.

[0020] In this embodiment, a universal joint is used as the connecting portion 12, but this is not limited to this as long as it connects adjacent extension units 11.

[0021] A control unit 14 is connected to the robot main 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 of the extension units 11 via the piping 13. By supplying fluid in a predetermined pattern from the control unit 14 to the inside of the cylindrical portion 11a of each of the extension units 11, the multiple extension units 11 perform peristaltic movements in the predetermined pattern, allowing the robot main body 10 to move inside the pipe.

[0022] FIG. 2 shows an example of a pattern of peristaltic movement of the multiple telescopic units 11 when the robot body 10 moves axially inside the pipe 2 to one side, i.e., when moving forward toward the left side in FIG. 2 .

[0023] First, as shown in Fig. 2(a), the leftmost (front) telescopic unit 11 and the second-left telescopic unit 11 in Fig. 2 are expanded radially and contracted axially. The two telescopic units 11 expanded radially each come into contact with the inner circumferential surface of the pipe 2 over the entire circumference. As a result, the robot body 10 is held in the axial direction by the two telescopic units 11 expanded radially.

[0024] Next, from the state shown in Fig. 2(a), as shown in Fig. 2(b), the leftmost telescopic unit 11 is returned to its original shape, and 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 abuts against the inner circumferential surface of the pipe 2 and maintains its axial position, so the leftmost telescopic unit 11 contracts radially and extends axially to return to its original shape, and the left end (front end) of the robot body 10 moves leftward from the position shown in Fig. 2(a). Furthermore, since the third telescopic unit 11 from the left expands radially and contracts axially while the second telescopic unit 11 abuts against the inner circumferential surface of the pipe 2 and maintains its axial position, the right end (rear end) of the robot body 10 also moves leftward from the position shown in Fig. 2(a).

[0025] Next, from the state shown in Fig. 2(b), as shown in Fig. 2(c), the second telescopic unit 11 from the left is returned to its original shape, and the fourth telescopic unit 11 from the left is expanded radially while contracting axially. At this time, the third telescopic unit 11 from the left abuts against the inner circumferential surface of the pipe 2 and maintains its axial position, so the second telescopic unit 11 from the left contracts radially and extends axially to return to its original shape, causing the left end (front end) of the robot body 10 to move further leftward from the position shown in Fig. 2(b). Furthermore, since the fourth telescopic unit 11 from the left expands radially while contracting axially while the third telescopic unit 11 abuts against the inner circumferential surface of the pipe 2 and maintains its axial position, the right end (rear end) of the robot body 10 also moves further leftward from the position shown in Fig. 2(b).

[0026] The same procedure is followed to operate the extension units 11 in the above pattern until the rightmost extension unit 11 is reached. Then, when the pattern reaches the rightmost extension unit 11, the operation returns to the beginning and the extension units 11 are operated in the above pattern, as shown in Figure 2(d).

[0027] In this way, by causing the multiple telescopic units 11 to perform peristaltic motion in the above-described pattern, the robot body 10 can move forward inside the pipe 2 toward the left in Fig. 2. Also, by operating the multiple telescopic units 11 in a pattern that is the left-right reverse of the pattern shown in Fig. 2, the robot body 10 can move backward inside the pipe 2 toward the right in Fig. 2.

[0028] The peristaltic movement pattern of the multiple extension units 11 in the robot body 10 is not limited to the above, and other patterns may be used as long as the robot body 10 can be moved forward and backward.

[0029] The robot body 10 may be provided with a transparent cover 15 at its tip (front end), and a camera (not shown) for capturing an image of the inside of the pipe 2 may be provided inside the cover 15 .

[0030] Next, the cleaning body 20 provided on the robot body 10 will be described.

[0031] The cleaning body 20 is used to clean the inside of the pipe 2 by collecting foreign matter (dirt) 3 such as dust adhering to the inner circumferential surface of the pipe 2 when the robot body 10 moves inside the pipe 2. As shown in Fig. 3, the cleaning body 20 is provided on the outer periphery of the robot body 10 so as to protrude radially outward.

[0032] 1 , in this embodiment, the robot body 10 is provided with a plurality of cleaning bodies 20 spaced apart in the axial direction of the robot body 10. More specifically, a cleaning body 20 is provided at each end of each extendable unit 11 in the axial direction. Note that, although the robot body 10 is provided with a plurality of cleaning bodies 20 in this embodiment, it is sufficient that the robot body 10 is provided with at least one cleaning body 20.

[0033] The cleaning body 20 has a substantially annular shape centered on the axis O of the robot body 10. The outer diameter of the cleaning body 20 is substantially the same as the inner diameter of the pipe 2 that is to be cleaned by the pipe cleaning robot 1. The outer diameter of the cleaning body 20 is preferably the same as or slightly larger than the inner diameter of the pipe 2 that is to be cleaned by the pipe cleaning robot 1. When the pipe cleaning robot 1 moves inside the pipe 2, the outer peripheral end 20a of the cleaning body 20 comes into contact with the inner peripheral surface of the pipe 2. Therefore, an external force is applied to the outer peripheral end 20a of the cleaning body 20 in a direction opposite to the direction in which the pipe cleaning robot 1 moves.

[0034] Here, the pipe cleaning robot 1 is configured so that a first reaction force generated when the outer peripheral end 20a of the cleaning body 20 is subjected to an external force in one axial direction is greater than a second reaction force generated when the outer peripheral end 20a of the cleaning body 20 is subjected to an external force in the other axial direction. In other words, in its natural state, the cleaning body 20 protrudes radially outward from the outer circumferential surface of the robot main body 10, and is configured so that when the outer peripheral end 20a is subjected to an external force in the axial direction from that state, the cleaning body 20 is more easily toppled in the direction toward one axial side than in the direction toward the other axial side, with the toppling reaction force being anisotropic.

[0035] More specifically, in the pipe cleaning robot 1 according to the first embodiment shown in Fig. 3, the cleaning body 20 is composed of a brush. That is, the cleaning body 20 is configured such that a large number of bristles protrude radially outward from the outer peripheral surface of the robot body 10, the bristles being arranged around the entire circumferential direction around the axis O. The large number of bristles constituting the brush are made of a flexible material, such as synthetic resin. Therefore, when an external force is applied in the axial direction to the outer peripheral end 20a, which is the radially outer end of the brush, the brush constituting the cleaning body 20 can bend and collapse in the axial direction in which the external force is applied.

[0036] A regulating body 21 is attached to the robot body 10, positioned on one side of the cleaning body 20 in the axial direction. In this embodiment, the regulating body 21 is an annular member with a smaller diameter than the cleaning body 20. More specifically, the regulating body 21 is a thin annular synthetic resin sheet with a smaller diameter than the cleaning body 20. The regulating body 21 is disposed with a gap in the axial direction relative to the cleaning body 20.

[0037] The regulating body 21 may have various configurations, such as a thin rubber sheet, a block-shaped body having a predetermined rigidity, etc. The regulating body 21 may also be disposed in contact with the cleaning body 20 without leaving any gap therebetween.

[0038] The regulating body 21 regulates tilt of the cleaning body 20 toward one axial side (the left side in FIG. 3 ). More specifically, when the cleaning body 20 tilts toward one axial side, the regulating body 21 abuts against a radially intermediate portion of the cleaning body 20. As a result, when an external force in the axial direction is applied to the outer peripheral end 20a of the cleaning body 20, the cleaning body 20 attempts to tilt toward one axial side at a portion that protrudes radially outward beyond the regulating body 21. Therefore, when the outer peripheral end 20a of the cleaning body 20 receives an external force toward one axial side, the first reaction force generated by the outer peripheral end 20a of the cleaning body 20 in response to the external force is larger than when the regulating body 21 is not provided. On the other hand, because the regulating body 21 is not provided on the other axial side of the cleaning body 20, when the outer peripheral end 20a of the cleaning body 20 receives an external force toward the other axial side, the second reaction force generated by the outer peripheral end 20a of the cleaning body 20 in response to the external force is smaller than the first reaction force.

[0039] In this way, the pipe cleaning robot 1 according to the first embodiment is configured such that the regulating body 21 is provided on one axial side of the cleaning body 20, so that the first reaction force generated when the outer peripheral end 20a of the cleaning body 20 is subjected to an external force directed toward one axial side is greater than the second reaction force generated when the outer peripheral end 20a of the cleaning body 20 is subjected to an external force directed toward the other axial side.

[0040] The first reaction force or the difference between the first reaction force and the second reaction force that occurs when the outer peripheral end 20a of the cleaning body 20 is subjected to an external force toward one side in the axial direction can be adjusted to a desired value by changing the outer diameter of the regulating body 21, the axial distance between the cleaning body 20 and the regulating body 21, the rigidity of the regulating body 21 (ease of deformation in the axial direction), etc.

[0041] According to the pipe cleaning robot 1 of the first embodiment having the above configuration, the brush constituting the cleaning body 20 is flexible enough to easily collapse so as to overcome foreign matter 3 adhering to the inner circumferential surface of the pipe 2. This makes it possible to select whether to sweep (scrape) the foreign matter 3 adhering to the inner circumferential surface of the pipe 2 to one side or the other in the axial direction by the cleaning body 20 when moving inside the pipe 2. As a result, for example, when cleaning a pipe 2 that is open at only one end and closed at the other end, the foreign matter 3 adhering to the inner circumferential surface of the pipe 2 can be swept out by the cleaning body 20 from the opening of the pipe 2 to the outside without leaving any foreign matter 3 inside the pipe 2.

[0042] That is, when cleaning a pipe 2 that is open at only one end and closed at the other end, with a conventional pipe cleaning robot that simply has a cleaning body attached to the outer periphery of the robot body, as the pipe cleaning robot moves forward from the opening of the pipe 2 toward the closed end of the pipe 2, foreign matter 3 adhering to the inner periphery of the pipe 2 is pushed by the cleaning body and pushed into the closed end of the pipe 2. Then, when the pipe cleaning robot moves backward from the closed end of the pipe 2 toward the end with the opening and returns to the opening, the foreign matter 3 pushed into the closed end of the pipe 2 during its forward movement remains inside the pipe 2. As a result, the inside of the pipe 2 cannot be cleaned effectively.

[0043] In contrast, in the pipe cleaning robot 1 according to the first embodiment, as shown in FIG. 4( a), when the cleaning body 20 moves forward from the opening of the pipe 2 toward the closed end of the pipe 2 (left side in FIG. 4), the cleaning body 20 is not restricted by the restricting body 21 and can easily tilt toward the other side in the axial direction so as to climb over foreign matter 3 adhering to the inner circumferential surface of the pipe 2. Therefore, the foreign matter 3 adhering to the inner circumferential surface of the pipe 2 is not pushed into the closed end of the pipe 2 by the cleaning body 20, and remains attached to the inner circumferential surface of the pipe 2. On the other hand, as shown in FIG. 4( b), when the pipe cleaning robot 1 moves backward from the closed end of the pipe 2 toward the end with the opening (right side in FIG. 4) and returns to the opening, the restricting body 21 restricts the cleaning body 20 from tilting toward one side in the axial direction, making it difficult for the cleaning body 20 to tilt. Therefore, the foreign matter 3 remaining attached to the inner circumferential surface of the pipe 2 is scraped off by the cleaning body 20 and pushed toward the opening of the pipe 2 as the pipe cleaning robot 1 moves backward. Therefore, according to the pipe cleaning robot 1 of this embodiment, when cleaning a pipe 2 that is open at only one end and closed at the other end, the cleaning body 20 can sweep out foreign matter 3 attached to the inner surface of the pipe 2 from the opening of the pipe 2 to the outside without leaving any foreign matter 3 inside the pipe 2.

[0044] In this way, the pipe cleaning robot 1 is configured so that the first reaction force generated when the outer peripheral end 20a of the cleaning body 20 is subjected to an external force toward one side in the axial direction is greater than the second reaction force generated when the outer peripheral end 20a of the cleaning body 20 is subjected to an external force toward the other side in the axial direction.Therefore, for example, when cleaning a pipe 2 that is open at only one end and closed at the other end, foreign matter 3 inside the pipe 2 can be swept out of the pipe 2 without remaining inside the pipe 2.

[0045] Furthermore, when the pipe cleaning robot 1 is configured with a plurality of cleaning bodies 20 spaced apart in the axial direction on the robot body 10, each cleaning body 20 can sweep foreign matter 3 inside the pipe 2 out of the pipe 2 without leaving any inside the pipe 2.

[0046] Furthermore, when the pipe cleaning robot 1 is configured such that multiple cleaning bodies 20 are provided axially spaced apart on the robot main body 10, as shown in Figure 5, it can be configured so that the first reaction force generated when the outer peripheral end 20a of the cleaning body 20 on one axial side (left side in Figure 5) of a pair of axially adjacent cleaning bodies 20 is subjected to an external force directed toward one axial side is greater than the first reaction force generated when the outer peripheral end 20a of the cleaning body 20 on the other axial side (right side in Figure 5) is subjected to an external force directed toward one axial side.

[0047] In the case shown in Figure 5, of a pair of cleaning bodies 20 adjacent in the axial direction, the outer diameter of the regulating body 21 located on one axial side (left side in Figure 5) of the cleaning body 20 on one axial side (left side in Figure 5) is made larger than the outer diameter of the regulating body 21 located on one axial side (left side in Figure 5) of the cleaning body 20 on the other axial side (right side in Figure 5), so that the cleaning body 20 on one axial side (left side in Figure 5) has a larger first reaction force generated when its outer peripheral end 20a is subjected to an external force directed toward one axial side.

[0048] With this configuration, as the pipe cleaning robot 1 retreats from the closed end of the pipe 2 toward the end with the opening (the right side in Figure 5) and returns to the opening, foreign matter 3 remaining on the inner surface of the pipe 2 is scraped off little by little by the cleaning body 20 furthest forward in the direction of travel of the retreating pipe cleaning robot 1 (the rightmost in Figure 5) to the rearmost cleaning body 20, so that foreign matter 3 can be swept out toward the opening evenly from all longitudinal parts of the pipe cleaning robot 1. This allows foreign matter 3 inside the pipe 2 to be swept out of the pipe 2 without being left inside the pipe 2.

[0049] In addition to the method of making the outer diameter of the regulating body 21 different as described above, the axial distance between the cleaning body 20 and the regulating body 21, the rigidity of the regulating body 21 (ease of deformation in the axial direction), etc. may be made different for each cleaning body 20, so that the cleaning body 20 on one side in the axial direction (left side in Figure 5) will have a larger first reaction force when its outer peripheral end 20a is subjected to an external force toward one side in the axial direction.

[0050] As shown as a modified example in Figure 6, the pipe cleaning robot 1 according to the first embodiment can also be configured such that a sub-regulator 22 is attached to the robot main body 10 on the opposite side of the cleaning body 20 from the regulator 21. In this case, the sub-regulator 22 is configured so that the second reaction force acting on the cleaning body 20 is not greater than the first reaction force. In the case shown in Figure 6, the sub-regulator 22 has a smaller outer diameter than the regulator 21, and the axial distance between the sub-regulator 22 and the cleaning body 20 is greater than the axial distance between the cleaning body 20 and the regulator 21.

[0051] In addition, the sub-regulator 22 may be configured so that the second reaction force is not greater than the first reaction force acting on the cleaning body 20 by either making the outer diameter smaller than that of the regulator 21 or by making the axial distance from the cleaning body 20 larger, or by both.

[0052] By providing the sub-regulator 22 to the pipe cleaning robot 1, the regulator 21 can set a desired value for the first reaction force generated when the outer peripheral end 20a of the cleaning body 20 is subjected to an external force toward one axial direction, and a desired value for the second reaction force generated when the outer peripheral end 20a of the cleaning body 20 is subjected to an external force toward the other axial direction. As a result, as shown in Fig. 6(a) , when the pipe cleaning robot 1 advances toward one axial direction (the left side in Fig. 6) inside the pipe 2, the sub-regulator 22 appropriately suppresses the tilt of the cleaning body 20, allowing the cleaning body 20 to overcome foreign matter 3 adhering inside the pipe 2 while ensuring that substantially the entire outer peripheral end 20a of the cleaning body 20 contacts the inner circumferential surface of the pipe 2 in portions of the pipe 2 where foreign matter 3 is not adhering. Therefore, as the pipe cleaning robot 1 advances inside the pipe 2, the robot main body 10 is accurately held (centered) in the center of the pipe 2 by the cleaning body 20, allowing the pipe cleaning robot 1 to move more efficiently inside the pipe 2. As shown in Figure 6(b), when the pipe cleaning robot 1 retreats inside the pipe 2 toward the other axial side (the right side in Figure 6), the cleaning body 20 pushes the foreign object 3 out of the pipe 2, as in the case shown in Figure 4(b), and the foreign object 3 inside the pipe 2 can be swept out of the pipe 2 without remaining inside the pipe 2.

[0053] As shown in another modified example in FIG. 7 , the regulator 21 and the sub-regulator 22 may be configured as annular blocks having the same outer diameter. In this case, the chamfered portion 21a formed between the surface of the regulator 21 facing the cleaning body 20 and the surface facing radially outward may be smaller than the chamfered portion 22a formed between the surface of the sub-regulator 22 facing the cleaning body 20 and the surface facing radially outward, thereby preventing the second reaction force acting on the cleaning body 20 from being greater than the first reaction force. The chamfered portions 21a and 22a are not limited to the linear shapes shown in FIG. 7 in cross section, but may each have a convex curved shape in cross section. Even with this configuration, the same effect as that of the pipe cleaning robot 1 shown in FIG. 6 can be achieved. That is, as shown in Figure 7(a), when the pipe cleaning robot 1 advances through the inside of the pipe 2 toward one axial side (left side in Figure 7), the sub-regulator 22 moderately restricts the tilt of the cleaning body 20, so that the cleaning body 20 moves over foreign matter 3 attached inside the pipe 2 while allowing substantially the entire outer circumferential edge 20a of the cleaning body 20 to contact the inner circumferential surface of the pipe 2 in parts of the pipe 2 where foreign matter 3 is not attached. Therefore, as the pipe cleaning robot 1 advances through the inside of the pipe 2, the robot main body 10 is more accurately held (centered) in the center of the pipe 2 by the cleaning body 20, allowing the pipe cleaning robot 1 to move more efficiently inside the pipe 2. Furthermore, as shown in Figure 7(b), when the pipe cleaning robot 1 retreats through the inside of the pipe 2 toward the other axial side (right side in Figure 7), the cleaning body 20 pushes the foreign matter 3 out of the pipe 2, sweeping the foreign matter 3 out of the pipe 2 without leaving any inside the pipe 2.

[0054] Next, a pipe cleaning robot 100 according to a second embodiment of the present invention will be described with reference to Figures 8 and 9. In Figures 8 and 9, members and parts corresponding to those previously described are given the same reference numerals. Furthermore, in the pipe cleaning robot 100 according to the second embodiment, the configuration of the robot body 10 is the same as the configuration of the robot body 10 of the pipe cleaning robot 1 according to the first embodiment, so a repeated description will be omitted.

[0055] The pipe cleaning robot 100 according to the second embodiment differs from the pipe cleaning robot 1 according to the first embodiment in the configuration of the cleaning body 20. Note that the pipe cleaning robot 100 according to the second embodiment does not have the regulating body 21 and the sub-regulating body 22.

[0056] In the pipe cleaning robot 100 according to the second embodiment, the cleaning body 20 is configured as an umbrella-shaped elastic body in which the inner peripheral end 20b, which is fixed to the robot main body 10, is offset to one side in the axial direction (left side in FIG. 8 ) relative to the outer peripheral end 20a. Various types of rubber and elastomers can be used as the elastic body constituting the cleaning body 20. The portion of the cleaning body 20 between the outer peripheral end 20a and the inner peripheral end 20b is frusto-conical in shape. The thickness of the frusto-conical portion gradually increases from the radial center toward the inner peripheral end 20b. The shape of the portion of the cleaning body 20 between the outer peripheral end 20a and the inner peripheral end 20b is not limited to a frusto-conical shape, and it may be, for example, dome-shaped, as long as the entire cleaning body 20 has an umbrella-like shape.

[0057] With this configuration, the cleaning body 20 is less likely to tilt to one side in the axial direction (the left side in Fig. 8 ) and more likely to tilt to the other side in the axial direction (the right side in Fig. 8 ). In other words, the pipe cleaning robot 100 according to the second embodiment is also configured so that the first reaction force generated when the outer peripheral end 20 a of the cleaning body 20 is subjected to an external force toward one side in the axial direction is greater than the second reaction force generated when the outer peripheral end 20 a of the cleaning body 20 is subjected to an external force toward the other side in the axial direction.

[0058] According to the pipe cleaning robot 1 of the second embodiment having the above configuration, the cleaning body 20 is flexible enough to be easily toppled over so that it can climb over foreign matter 3 adhering to the inner surface of the pipe 2. Therefore, when cleaning a pipe 2 that is open at only one end and closed at the other end, the cleaning body 20 can sweep the foreign matter 3 adhering to the inner surface of the pipe 2 out through the opening of the pipe 2 to the outside without leaving any of it inside the pipe 2.

[0059] That is, as shown in Fig. 9(a) , in the pipe cleaning robot 100 according to the second embodiment, when it moves forward from the opening of the pipe 2 toward the closed end of the pipe 2 (left side in Fig. 9 ), the cleaning body 20 easily deforms like a closing umbrella, allowing it to climb over foreign matter 3 adhering to the inner circumferential surface of the pipe 2. As a result, the foreign matter 3 adhering to the inner circumferential surface of the pipe 2 is left adhering to the inner circumferential surface of the pipe 2 without being pushed into the closed end by the cleaning body 20. On the other hand, as shown in Fig. 9(b) , when the pipe cleaning robot 100 moves backward from the closed end of the pipe 2 toward the end with the opening (right side in Fig. 9 ) and returns to the opening, the cleaning body 20 is unlikely to tilt to one side in the axial direction, so that the foreign matter 3 remaining adhering to the inner circumferential surface of the pipe 2 is scraped off by the cleaning body 20 and pushed toward the opening of the pipe 2. In this way, when cleaning a pipe 2 that is open at only one end and closed at the other end, the pipe cleaning robot 100 according to the second embodiment can sweep foreign matter 3 adhering to the inner surface of the pipe 2 out of the opening of the pipe 2 using the cleaning body 20 without leaving any foreign matter 3 inside the pipe 2.

[0060] In the pipe cleaning robot 100 according to the second embodiment, the umbrella-shaped cleaning body 20 may be divided radially around the axis O. That is, the umbrella-shaped cleaning body 20 may be divided into multiple parts arranged in the circumferential direction. This configuration makes it easier for the cleaning body 20 to tilt when the pipe cleaning robot 100 moves forward.

[0061] Next, a pipe cleaning robot 200 according to a third embodiment of the present invention will be described with reference to Figure 10. In Figure 10, members and parts corresponding to those previously described are given the same reference numerals. Furthermore, in the pipe cleaning robot 1 according to the third embodiment, the configuration of the robot body 10 is the same as the configuration of the robot body 10 of the pipe cleaning robot 1 according to the first embodiment, so a repeated description will be omitted.

[0062] The pipe cleaning robot 200 according to the third embodiment differs from the pipe cleaning robot 1 according to the first embodiment in the configuration of the cleaning body 20. Note that the pipe cleaning robot 200 according to the third embodiment does not have the regulating body 21 and the sub-regulating body 22.

[0063] In the pipe cleaning robot 200 according to the third embodiment, the cleaning body 20 is made of a plate-like member that is supported on the robot body 10 so as to be tiltable about a rotation axis 23. A plurality of cleaning bodies 20 made of plate-like members are provided on the outer circumferential surface of the robot body 10, lined up in the circumferential direction around the axis O. In other words, a plurality of cleaning bodies 20, each made of a plate-like member, are radially arranged on the outer circumferential surface of the robot body 10.

[0064] The plate-like member constituting the cleaning body 20 can be made of various materials, such as a metal plate that is a rigid body that does not substantially deform elastically, such as an aluminum alloy or steel, or an elastically deformable plate, such as a synthetic resin plate. Also, the plate-like member constituting the cleaning body 20 can be made mostly of a rigid body with the outer peripheral edge 20a being made of an elastic body.

[0065] The rotation shaft 23 is attached to the robot body 10 in a position along the tangential direction of the outer circumferential surface of the robot body 10 at the portion of the robot body 10 where the cleaning body 20 is provided. The cleaning body 20 is rotatably supported on the rotation shaft 23 at the side of the inner circumferential end 20b. Therefore, the cleaning body 20 can tilt around the rotation shaft 23 in a direction approaching or moving away from the outer circumferential surface of the robot body 10 while the outer circumferential end 20a moves in the axial direction.

[0066] A stopper body 24 is attached to the robot main body 10. The stopper body 24 is an annular block body extending in the circumferential direction and is fixed to one axial side of the cleaning body 20 (the left side in FIG. 10 ). The stopper body 24 prevents the cleaning body 20 from tilting to one axial side from its upright position along the radial direction. In other words, by abutting against the stopper body 24, the cleaning body 20 cannot tilt to one axial side from its upright position along the radial direction.

[0067] The stopper body 24 is not limited to the above configuration, and can have various configurations, such as one that restricts the rotation range of the rotating shaft 23, as long as it can prevent the cleaning body 20 from tilting to one side in the axial direction from the upright position along the radial direction.

[0068] An elastic member 25 is also attached to the robot body 10. The elastic member 25 is arranged on the other axial side of the cleaning body 20 (the right side in FIG. 10 ) and is configured to apply an elastic force to the cleaning body 20 in one axial direction. In the illustrated case, the elastic member 25 is a torsion spring and is arranged between the cleaning body 20 and the outer circumferential surface of the robot body 10. Note that the elastic member 25 is not limited to a torsion spring, and various other members can be used, such as other types of springs or members made of an elastic material such as rubber, as long as they can apply an elastic force to the cleaning body 20 in one axial direction.

[0069] With this configuration, the cleaning body 20 cannot tilt to one side in the axial direction (the left side in Fig. 10), but can easily tilt to the other side in the axial direction (the right side in Fig. 10). In other words, the pipe cleaning robot 200 according to the third embodiment is also configured so that the first reaction force generated when the outer peripheral end 20a of the cleaning body 20 is subjected to an external force toward one side in the axial direction is greater than the second reaction force generated when the outer peripheral end 20a of the cleaning body 20 is subjected to an external force toward the other side in the axial direction.

[0070] According to the pipe cleaning robot 1 of the third embodiment having the above-described configuration, the elastic member 25 is designed to generate an elastic force sufficient to allow the cleaning body 20 to easily collapse so that it can overcome foreign matter 3 adhering to the inner surface of the pipe 2. Therefore, when cleaning a pipe 2 that is open at only one end and closed at the other end, the cleaning body 20 can sweep the foreign matter 3 adhering to the inner surface of the pipe 2 out through the opening of the pipe 2 to the outside without leaving any of it inside the pipe 2.

[0071] That is, as shown in Fig. 10(a) , in the pipe cleaning robot 200 according to the third embodiment, when it moves forward from the opening of the pipe 2 toward the closed end of the pipe 2 (left side in Fig. 10 ), the cleaning body 20 can tilt by elastically deforming the elastic member 25, thereby climbing over foreign matter 3 adhering to the inner circumferential surface of the pipe 2. As a result, the foreign matter 3 adhering to the inner circumferential surface of the pipe 2 is left adhering to the inner circumferential surface of the pipe 2 without being pushed into the closed end of the pipe 2 by the cleaning body 20. On the other hand, as shown in Fig. 10(b) , when the pipe cleaning robot 200 moves backward from the closed end of the pipe 2 toward the end with the opening (right side in Fig. 10 ) and returns to the opening, the cleaning body 20 cannot tilt to one side in the axial direction, so that the foreign matter 3 remaining adhering to the inner circumferential surface of the pipe 2 is scraped off by the cleaning body 20 and pushed toward the opening of the pipe 2. In this way, when cleaning a pipe 2 that is open at only one end and closed at the other end, the pipe cleaning robot 200 according to the third embodiment can sweep foreign matter 3 adhering to the inner surface of the pipe 2 out of the opening of the pipe 2 using the cleaning body 20 without leaving any foreign matter 3 inside the pipe 2.

[0072] The pipe cleaning robot 1 according to the first embodiment, the pipe cleaning robot 100 according to the second embodiment, and the pipe cleaning robot 200 according to the third embodiment can all be used to clean pipes that are open at both ends. In this case, the pipe cleaning robot 1, 100, 200 is configured so that the cleaning body 20 generates a first reaction force when inserted into one end of the pipe and advances through the pipe, and generates a second reaction force when retreating through the pipe. This allows the cleaning body 20 to reliably sweep and remove foreign matter adhering to the inner surface of the pipe from the other end of the pipe as it advances through the pipe. Furthermore, when the pipe cleaning robot 1, 100, 200 retreats through the pipe after cleaning, the resistance between the cleaning body 20 and the inner surface of the pipe is reduced, allowing the pipe cleaning robot 1, 100, 200 to retreat faster through the pipe. This allows the pipe cleaning robot 1, 100, 200 to be quickly retrieved from one end of the pipe after cleaning.

[0073] The present invention is not limited to the above-described embodiment, and it goes without saying that various modifications can be made without departing from the spirit and scope of the present invention.

[0074] For example, in the first embodiment, the regulating body 21 is arranged on one axial side of the cleaning body 20 which is made up of a brush, in the second embodiment, the cleaning body 20 is made up of an umbrella-shaped elastic body whose inner peripheral end 20b, which is fixed to the robot main body 10, is shifted to one side in the axial direction relative to the outer peripheral end 20a, and in the third embodiment, a stopper body 24 is arranged on one axial side of the cleaning body 20 which is made up of a plate-shaped member supported so as to be able to tilt freely on the rotating shaft 23, and an elastic member 25 is arranged on the other side, so that the first reaction force generated when the outer peripheral end 20a of the cleaning body 20 is subjected to an external force toward one axial side is larger than the second reaction force generated when the outer peripheral end 20a of the cleaning body 20 is subjected to an external force toward the other axial side. However, this is not limited to this, and other configurations other than those described above may be used to make the first reaction force generated when the outer peripheral end 20a of the cleaning body 20 is subjected to an external force toward one axial side larger than the second reaction force generated when the outer peripheral end 20a of the cleaning body 20 is subjected to an external force toward the other axial side.

[0075] For example, in the first embodiment, the regulating body 21 is disposed on one axial side of the cleaning body 20 composed of a brush. However, as shown in Fig. 11 , a circular brush may be formed by bending a large number of bristles (brush fibers) so that they are of unequal lengths, passing the core wire 30 inside the bent portion, and crimping the outside with a metal plate 31, and attaching the brush to the robot body 10. The longer bristles of the brush serve as the cleaning body 20 and come into contact with the inner surface of the pipe 2, while the shorter bristles serve as the regulating body 21 and do not come into contact with the inner surface of the pipe 2. The bristles constituting the brush may be arranged in multiple rows in the direction of the axis O. Alternatively, a circular brush may be formed by bending the bristles of the brush so that they are of unequal lengths using a member other than the core wire 30 and the metal plate 31.

[0076] 11(a), when the pipe cleaning robot 1 moves forward from the opening of the pipe 2 toward the closed end of the pipe 2 (left side in FIG. 11), the cleaning body 20, which is made up of the portion of the brush with longer bristles, is not restricted by the restricting body 21, which is made up of the portion of the brush with shorter bristles, and can easily tilt toward the other axial direction so as to climb over foreign matter 3 adhering to the inner circumferential surface of the pipe 2. On the other hand, as shown in FIG. 11(b), when the pipe cleaning robot 1 moves backward from the closed end of the pipe 2 toward the end with the opening (right side in FIG. 11) and returns to the opening, the cleaning body 20, which is made up of the portion of the brush with longer bristles, is restricted from tilting toward one axial direction by the restricting body 21, which is made up of the portion of the brush with shorter bristles, and can scrape off foreign matter 3 remaining adhering to the inner circumferential surface of the pipe 2 and push it toward the opening of the pipe 2. Therefore, even with this configuration, when cleaning a pipe 2 that is open at only one end and closed at the other end, foreign matter 3 adhering to the inner surface of the pipe 2 can be swept out from the opening of the pipe 2 to the outside by the cleaning body 20 without being left inside the pipe 2.

[0077] In addition, the cleaning body 20 may be made up of a brush similar to that shown in Figure 4, and the regulating body 21 may be made up of a brush different from the brush that makes up the cleaning body 20, but with a number of bristles (brush fibers) that are shorter than the brush that makes up the cleaning body 20.

[0078] REFERENCE SIGNS LIST 1 Pipe cleaning robot 2 Pipe 3 Foreign object 10 Robot body 11 Extendable unit 11a Cylindrical part 12 Connecting part 13 Pipe 14 Control part 15 Cover 20 Cleaning body 20a Outer peripheral end 20b Inner peripheral end 21 Regulating body 21a Chamfered part 22 Sub-regulating body 22a Chamfered part 23 Rotating shaft 24 Stopper body 25 Elastic member 30 Core wire 30 31 Metal plate 31 100 Pipe cleaning robot 200 Pipe cleaning robot O Axis

Claims

1. A pipe cleaning robot comprising a robot body equipped with at least three telescopic units that expand radially and contract axially when supplied with fluid, and a cleaning body that protrudes radially outward from the outer periphery of the robot body, wherein the telescopic units perform peristaltic motion in a predetermined pattern, causing the robot body to move inside the pipe and clean the inside of the pipe with the cleaning body; wherein a first reaction force generated when the outer peripheral end of the cleaning body is subjected to an external force toward one side in the axial direction is greater than a second reaction force generated when the outer peripheral end of the cleaning body is subjected to an external force toward the other side in the axial direction, the cleaning body comprising a brush; and a regulating body attached to the robot body in the axial direction, which is positioned on one side of the cleaning body and comes into contact with the cleaning body to regulate the inclination of the cleaning body to one side in the axial direction when the outer peripheral end of the cleaning body is subjected to an external force toward one side in the axial direction while the cleaning body is in contact with the inner surface of the pipe.

2. The pipe cleaning robot according to claim 1, wherein a plurality of said cleaning bodies are provided on said robot body at intervals in said axial direction.

3. A pipe cleaning robot as described in claim 2, wherein the first reaction force generated when the outer peripheral end of the cleaning body on one side of the axial direction of a pair of adjacent cleaning bodies is subjected to an external force toward the one side in the axial direction is greater than the first reaction force generated when the outer peripheral end of the cleaning body on the other side of the axial direction is subjected to an external force toward the one side in the axial direction.

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