In-pipe mobile robot

Abstract

To provide an in-pipe mobile robot of a peristaltic motion type using pneumatic pressure that can obtain large traction and propulsion forces while maintaining flexibility.SOLUTION: An in-pipe mobile robot comprises a mobile body configured to be movable inside a pipe, and a control device which controls operation of the mobile body. The in-pipe mobile robot comprises: a gripping force generation section which is composed of an elastic material, and expands by supply of a fluid to a size that generates friction with an inner wall of the pipe, and contracts by discharge of the supplied fluid by elasticity thereof; a traction force generation section which is composed of an elastic material, and expands in a radial direction and shortens in a pipe-axis direction by supply of a fluid, and contracts in the radial direction and extends in the pipe-axis direction by discharge of the supplied fluid; and a push-pull-force generation section which is composed of an elastic material, and extends substantially only in the pipe-axis direction by supply of a fluid, and shortens substantially only in the pipe-axis direction by discharge of the supplied fluid. The mobile body has a configuration in which, in order from a front side in a traveling direction, the gripping force generation section, the push-pull-force generation section, the gripping force generation section, the traction force generation section, and the gripping force generation section are connected.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to an in-pipe mobile robot, and more particularly to an in-pipe mobile robot that moves within a pipe by utilizing peristaltic movement. [Background technology]

[0002] In recent years, there has been an increase in accidents involving pipe damage caused by corrosion and cracks. To prevent these accidents, regular inspections of the inside of pipes are necessary. For example, industrial endoscopes are often used for conventional pipe inspections. However, when inspecting complex piping with many small-diameter bends, the pushing force is not transmitted to the front due to buckling of the endoscope and friction that occurs around it, making it difficult to inspect long distances along the entire piping. Therefore, self-propelled in-pipe mobile robots equipped with endoscopes and self-propelling functions have been developed. For example, wheeled, crawler, snake-like, walking, and ciliary vibration types have been proposed as self-propelled in-pipe mobile robots. However, these robots have several problems when inspecting the inside of long-distance pipes with many small-diameter bends. For example, wheel-type, crawler-type, and snake-type robots have fast movement speeds, but their structures tend to be complicated and it is difficult to miniaturize them. Furthermore, walking-type robots have a small contact area with the pipe wall, so they lack the traction force to move long distances through the pipe. Furthermore, ciliary vibration-type robots have difficulty moving through vertically extending pipes and moving backward. To inspect the inside of complex, thin-diameter pipes over long distances, a self-propelled in-pipe mobile robot must have a small, flexible structure as well as sufficient traction force. Therefore, for example, as shown in Patent Document 1, a peristaltic movement type in-pipe mobile robot has been proposed, which focuses on the peristaltic movement of earthworms. The peristaltic in-pipe robot is constructed with multiple connected segments of the same structure, similar to an earthworm, and by increasing or decreasing the air pressure in each segment, it expands and contracts repeatedly from front to back, allowing it to propel itself even in narrow spaces.In addition, the large contact area of ​​each segment with the pipe wall allows for stable movement and high traction force. Peristaltic in-pipe robots have a better power-to-weight ratio and are more flexible than wheeled robots, making them suitable for long-distance inspection of small, complex pipes. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Publication No. 2022-58664 Summary of the Invention [Problem to be solved by the invention]

[0004] However, in long-distance pipes with many bends, the frictional forces acting on the wiring that supplies air, the working medium of a peristaltic in-pipe robot, are large, making it difficult to inspect the entire pipe even with the large traction force of the peristaltic in-pipe robot, and reducing the robot's movement speed. Furthermore, since the propulsion force depends on the passive elastic force of the material, a material with a large elastic modulus is required to achieve a large propulsion force. However, using a material with a large elastic modulus can result in a lack of flexibility in the robot, making it difficult for the robot to pass through bent pipes. Therefore, there is a need for a peristaltic in-pipe robot that can generate both traction and propulsion while maintaining flexibility.

[0005] Therefore, an object of the present invention is to provide an in-pipe mobile robot that uses air pressure to move in a peristaltic motion and that can obtain large traction and propulsion forces while maintaining flexibility. [Means for solving the problem]

[0006] In order to solve the above-mentioned problems, the in-pipe mobile robot is configured to have a mobile body configured to be able to move within a pipe and a control device that controls the operation of the mobile body, and is equipped with a gripping force generating unit made of an elastic material that expands to a size that generates friction with the inner wall of the pipe when fluid is supplied to it and contracts due to its elasticity when the supplied fluid is discharged, a traction force generating unit made of an elastic material that expands radially and contracts in the axial direction of the pipe when fluid is supplied to it, and contracts radially and extends in the axial direction when the supplied fluid is discharged, and a push / pull force generating unit made of an elastic material that expands substantially only in the axial direction of the pipe when fluid is supplied to it and contracts substantially only in the axial direction when the supplied fluid is discharged, and the mobile body is configured so that, from the front in the direction of travel, the gripping force generating unit, push / pull force generating unit, gripping force generating unit, traction force generating unit, and gripping force generating unit are connected in this order. According to this configuration, a peristaltic movement type in-pipe mobile robot using air pressure can obtain large traction and propulsion forces while maintaining flexibility. In addition, as another configuration of the in-pipe mobile robot, the traction force generating unit may comprise a cylindrical elastic body formed in a cylindrical shape, end members that close the openings at both ends of the cylindrical elastic body, and a closed space surrounded by the inner surface of the cylindrical elastic body and the end members by closing the end members, and the cylindrical elastic body may comprise fibers that restrain the radial expansion of the cylindrical elastic body when a fluid is supplied to the closed space, and the fibers may extend spirally from one end side to the other end side of the cylindrical elastic body. As another configuration of the intra-pipe mobile robot, a gripping force generating unit connected rearward of the pushing / pulling force generating unit in the direction of travel may be configured to expand radially and shorten in the axial direction of the pipe when fluid is supplied thereto, and to contract radially and extend in the axial direction of the pipe when the supplied fluid is discharged, or a gripping force generating unit connected forward of the pushing / pulling force generating unit in the direction of travel may be configured to expand radially and shorten in the axial direction of the pipe when fluid is supplied thereto, and to contract radially and extend in the axial direction of the pipe when the supplied fluid is discharged. As another configuration of the in-pipe mobile robot, the traction force generating unit may be configured to expand to a size that generates friction with the inner wall of the pipe when a fluid is supplied, or the traction force generating unit may be configured to expand to a size that does not generate friction with the inner wall of the pipe when a fluid is supplied. In addition, as another configuration of the intra-pipe mobile robot, the control device may be configured to expand the gripping force generating unit connected behind the pushing / pulling force generating unit in the direction of travel, and then extend the pushing / pulling force generating unit, move the gripping force generating unit connected in front of the pushing / pulling force generating unit forward, and then expand the gripping force generating unit connected in front of the pushing / pulling force generating unit, and cause the gripping force generating unit connected behind the pushing / pulling force generating unit, the traction force generating unit, and the gripping force generating unit to perform peristaltic movements while maintaining the expanded state of the gripping force generating unit connected in front of the pushing / pulling force generating unit. [Brief explanation of the drawings]

[0007] [Figure 1] FIG. 1 is a schematic diagram of an in-pipe mobile robot. [Figure 2] 1A and 1B show an axial cross-sectional view of an actuator constituting a gripping force generating section and a radial cross-sectional view of an outer cylinder. [Figure 3] FIG. 10 is a diagram illustrating the extension and contraction operation of the gripping unit; [Figure 4] 1A and 1B show an axial cross-sectional view of an actuator constituting a traction force generating unit and a radial cross-sectional view of an outer cylinder. [Figure 5] FIG. 10 is a diagram illustrating the extension and contraction operation of the traction unit; [Figure 6] 10A and 10B are diagrams illustrating an example of an actuator that configures a pushing / pulling force generating unit. [Figure 7] FIG. [Figure 8] FIG. 10 is a diagram illustrating an example of a unit support member. [Figure 9] FIG. 10 is a diagram illustrating an example of a propulsion operation of a moving body.

[0008] The present invention will be described in detail below through embodiments of the invention. However, the following embodiments do not limit the invention according to the claims, and not all of the combinations of features described in the embodiments are necessarily essential to the solution of the invention, and include configurations that can be selectively adopted. DETAILED DESCRIPTION OF THE INVENTION

[0009] FIG. 1 is a schematic diagram showing an example of an in-pipe mobile robot according to this embodiment. As shown in FIG. 1, the in-pipe mobile robot 1 includes a mobile object 2 that moves within a pipe, and a control device 100 that controls the operation of the mobile object 2. The moving body 2 according to this embodiment is configured to move within a pipe by using air pressure to perform an action that mimics peristaltic movement. The moving body 2 includes a gripping force generating unit 4, a traction force generating unit 6, and a pushing / pulling force generating unit 8. Hereinafter, the gripping force generating portion may be referred to as a gripping portion, the traction force generating portion may be referred to as a traction portion, and the push-pull force generating portion may be referred to as a push-pull portion, etc.

[0010] The gripping force generating unit 4 is a part that generates friction between the moving body 2 and the pipe when the moving body 2 moves through the pipe simulating peristaltic movement. As shown in Fig. 1, the gripping force generating unit 4 is provided as a front gripping unit 4 connected to the front side of the pushing / pulling force generating unit 8, an intermediate gripping unit 4 provided between the pushing / pulling force generating unit 8 and the traction force generating unit 6, and a rear gripping unit 4 connected to the rear of the traction force generating unit 6. In this embodiment, the front gripping portion 4, the middle gripping portion 4, and the rear gripping portion 4 are described as having the same configuration. In the following description, when the positions of the gripping force generating units 4 are specified, they will be referred to as the front gripping unit 4A, the middle gripping unit 4B, and the rear gripping unit 4C, and when not specified, they will simply be referred to as the gripping force generating units 4.

[0011] [Gripping force generator] Fig. 2 shows an axial cross-sectional view of a gripping unit constituting a gripping force generating section and a radial cross-sectional view of an outer cylinder, and Fig. 3 shows the extension and contraction operation of the gripping unit. Each gripping force generating unit 4 is configured as an actuator that operates by air pressure, and when compressed air is supplied, it contracts axially while expanding radially outward, and when the supplied compressed air is discharged, it expands axially while contracting radially inward. In this embodiment, the description will be given assuming that each gripping force generating unit 4 is configured by one actuator. The actuator configuring the gripping force generating unit 4 is referred to as a gripping unit 10.

[0012] As shown in Figure 2, the gripping unit 10 comprises an inner tube 12, an outer tube 14 that surrounds the outer periphery of the inner tube 12 and forms a double tube, and a pair of end members 16;16 that are provided at each end of the inner tube 12 and the outer tube 14 and close the space formed between the inner tube 12 and the outer tube 14.

[0013] The inner cylinder 12 is a cylindrical body that allows expansion and contraction in the axial direction but does not expand and contract in the radial direction. The inner cylinder 12 is preferably made of a flexible material that allows bending of the axis and is not easily deformed by pressure from the inner or outer circumferential sides.

[0014] For example, the inner tube 12 can be a cylindrical body such as a bellows made of an elastic material, or a cylindrical body made by wrapping a non-stretchable, non-breathable, yet flexible film or sheet around the outer periphery of a coil spring. In this embodiment, a case will be described in which a bellows having a spiral bellows structure and a circular cross section is used for the inner cylinder 12, but the invention is not limited to this.

[0015] The outer cylinder 14 includes a cylindrical cylinder body 14A made of an elastic material and includes a plurality of fibers 14B inside the cylinder body 14A. The cylindrical body 14A is preferably made of an elastic, non-breathable, stretchable material such as synthetic rubber such as silicone rubber or natural rubber such as natural latex rubber. The cylindrical body 14A may be made of any material as long as its shape can be changed by supplying or discharging compressed air to or from the fluid chamber S10 (described later).

[0016] The fibers 14B extend along the axial direction and are embedded in a distributed manner in the circumferential and radial directions of the cylindrical body 14A so as to obtain isotropic radial expansion when the outer cylinder 14 expands. The fibers 14B are arranged within the wall thickness of the outer cylinder 14, for example, by extending along the axis of the cylindrical body 14A so as to have a length that extends continuously from one axial end to the other end. In this embodiment, a plurality of layers are stacked and densely inserted as shown in Fig. 2. The fibers 14B may be a single layer without being stacked.

[0017] 2 and 3 are merely conceptual illustrations of the lengths and directional distribution of the fibers 14B, and the lengths and directional distribution of the fibers 14B are not limited to those shown in the figures. Furthermore, the fact that the fibers 14B extend along the axial direction does not mean that the fibers 14B extend strictly parallel to the axial direction, but rather that they may be slightly inclined (intersecting) relative to the axial direction due to the nature of the fibers 14B.

[0018] Furthermore, fibers 14B are not limited to fibers having a length dimension in the axial direction of tubular body 14A, but may be shorter than the axial length dimension of tubular body 14A and distributed so that the fibers overlap each other in the circumferential, radial, and axial directions.

[0019] The end member 16 is formed as a cylindrical body and includes an inner tube fixing portion 17 for fixing the inner tube 12, an outer tube fixing portion 18 for fixing the outer tube 14, and a unit connecting portion 19 for connecting to the connecting unit 70. The end member 16 can be made of, for example, resin, hard rubber, metal, etc. Preferably, the end member 16 is made of a lightweight material.

[0020] The inner tube fixing portion 17 is provided on one end side of the inner peripheral surface of the end member 16 so that the outer periphery of the inner tube 12 can be fitted thereto. In this embodiment, since the inner tube 12 has a spiral bellows structure, for example, the inner tube fixing portion 17 can utilize the spiral shape of the inner tube 12 to form a spiral groove into which the outer periphery of the inner tube 12 can be screwed and fixed. Hereinafter, in the axial direction of the end member 16, the side on which the inner cylinder fixing portion 17 is provided will be referred to as the inside, and the opposite side will be referred to as the outside.

[0021] When the inner tube fixing portion 17 is formed as a spiral groove, it is preferable to screw in the spiral ridge portion at least one pitch on the outer periphery of the inner tube 12, taking into consideration the airtightness with the inner tube 12. Also, by forming the inner tube fixing portion 17 to provide an interference fit when the inner tube 12 is screwed in, for example, the outer periphery of the inner tube 12 comes into close contact with the groove, thereby improving the airtightness between the end member 16 and the inner tube 12.

[0022] The fixing of the inner tube 12 to the end member 16 is not limited to the above embodiment, and may be modified as appropriate depending on the shape of the inner tube 12, etc., so that the inner tube 12 is fixed to the end member 16 in an airtight state.

[0023] The outer tube fixing portion 18 is provided on the outer peripheral surface of the end member 16. The outer tube fixing portion 18 is located a predetermined distance axially outward from the end face of the inner tube 12 fixed to the inner tube fixing portion 17. The outer tube fixing portion 18 is formed, for example, in a spherical or tapered shape so that the outer diameter gradually decreases as it goes axially outward around the outer periphery of the end member 16.

[0024] The outer tube 16 is fixed to the outer tube fixing portion 18 formed in this manner as follows: The end of the outer tube 14 is inserted into the end member 16 so that it passes the outer tube fixing portion 18 on the axially outer side. A ring-shaped crimping member 22 is placed over the outer peripheral surface of the inserted outer tube 14, and the crimping member 22 is fixed from the axially outer side with a fixing member 23 that can be tightened from the outer peripheral side of the outer tube 14 toward the end member 16, thereby making it possible to fix the end member 16 to the outer tube 14.

[0025] The method of fixing the end member 16 to the outer tube 14 is not limited to the above embodiment, and any method may be used as long as the outer tube 14 is fixed to the end member 16 in an airtight manner.

[0026] By fixing the end members 16;16 to both ends of the inner tube 12 and the outer tube 14 in this manner, a fluid chamber S10 is formed as a closed space surrounded by the outer surface of the inner tube 12, the inner surface of the outer tube 14, and the end members 16;16.

[0027] The unit connecting portion 19 is provided, for example, in a cylindrical shape that is exposed axially outward from the fixing member 23 when the outer cylinder 14 is fixed to the end member 16. By connecting a connecting unit 70 to this unit connecting portion 19, the gripping unit 10 can be connected to the gripping unit 10, the traction unit 30, the pushing unit 50, etc. This unit connecting portion 19 is provided with, for example, a pair of through holes 19h that penetrate the end member 16 in the radial direction and are used to fix the connecting unit 70.

[0028] The end member 16 is also provided with a supply / discharge hole 20 that connects the fluid chamber S to the outside. The supply / discharge hole 20 is formed so as to penetrate through the end member 16, for example, with one end opening at the inner peripheral surface of the end member 16 and the other end opening at the inner end surface of the end member 16. A tube (not shown) for supplying air to the fluid chamber S and discharging the supplied air is connected to a supply / discharge hole 20 that opens on the inner peripheral surface side of the end member 16. The supply / discharge hole 20 may be formed in any manner as long as it is capable of supplying and discharging air from the inner periphery of the end member 16 to the fluid chamber S10.

[0029] FIG. 3(a) shows the gripping unit 10 in a contracted state, and FIG. 3(b) shows the gripping unit 10 in an expanded state. The contracted state here refers to the state when the fluid chamber S10 is equal to atmospheric pressure, and the expanded state refers to the state in which the gripping unit 10 expands inside the pipe until the required friction is obtained between the pipe and the gripping unit. The gripping unit 10 functions as an actuator that operates by supplying air to the fluid chamber S10, and as shown in Figures 3(a) to 3(b), its length contracts axially from x10 to X10 while its outer diameter expands radially from d10 to D10 (hereinafter, this state will be referred to simply as the expanded state). Furthermore, by discharging air from the fluid chamber S10, the axial length increases from X10 to x10 and the radial outer diameter decreases from D10 to d10, as shown in Figure 3(b) to Figure 3(a) (hereinafter, this state will be referred to simply as the contracted state).

[0030] The dimensions of each part of the gripping unit 10 are set so that, when expanded, the desired friction is obtained between the gripping unit 10 and the inner wall of the pipe Z, i.e., so that the outer diameter D10 when expanded is greater than or equal to the inner diameter of the pipe Z to be inspected. The desired friction means, for example, a state in which a frictional force is obtained that prevents the moving body 2 from falling under its own weight when the moving body 2 moves in a portion extending in the vertical direction of the pipe Z or when the moving body 2 comes to a standstill.

[0031] [Traction force generating section] The traction force generating unit 6 according to this embodiment is configured by an actuator that operates by air pressure, and that contracts axially while expanding radially outward when compressed air is supplied, and that expands axially while contracting radially inward when the supplied compressed air is discharged. In this embodiment, the traction force generating section 6 will be described as being composed of three actuators. The actuators that make up the traction force generating section 6 will be referred to as traction units 30.

[0032] The traction unit 30 may be configured similarly to the gripping unit 10 . As shown in Figure 4, the traction unit 30 comprises an inner tube 32, an outer tube 34 that surrounds the outer periphery of the inner tube 32 and forms a double tube, and a pair of end members 36, 36 that are provided at each end of the inner tube 32 and the outer tube 34 and close the space formed between the inner tube 32 and the outer tube 34.

[0033] The inner cylinder 32 is a cylindrical body that allows expansion and contraction in the axial direction but does not expand and contract in the radial direction. The inner cylinder 32 is preferably made of a flexible material that allows bending of the axis and is not easily deformed by pressure from the inner or outer circumferential sides.

[0034] For example, the inner tube 32 can be a cylindrical body such as a bellows made of an elastic material, or a cylindrical body made by wrapping a non-stretchable, non-breathable, yet flexible film or sheet around the outer periphery of a coil spring. In this embodiment, a case will be described in which a bellows having a spiral bellows structure and a circular cross section is used for the inner cylinder 32, but the invention is not limited to this.

[0035] The outer tube 34 has a cylindrical tube body 34A made of an elastic material and includes a plurality of fibers 34B inside. The tube body 14A is preferably made of an elastic, non-breathable, stretchable material such as synthetic rubber such as silicone rubber or natural rubber such as natural latex rubber. The material forming the tube body 14A may be any material as long as its shape can be changed by supplying or discharging compressed air to or from the fluid chamber S30 (described later).

[0036] The fibers 34B extend along the axial direction and are embedded in a distributed manner in the circumferential and radial directions of the cylindrical body 34A so as to obtain isotropic radial expansion when the outer cylinder 34 expands. The fibers 34B are arranged within the wall thickness of the outer cylinder 34, for example, by extending along the axis of the fibers 34B that have a length that extends continuously from one axial end to the other axial end of the cylindrical body 34A. In this embodiment, a plurality of layers are stacked and densely inserted as shown in Fig. 4. The fibers 34B may be a single layer without being stacked.

[0037] 4 and 5 are merely conceptual illustrations of the lengths and directional distribution of the fibers 34B, and the lengths and directional distribution of the fibers 34B are not limited to those shown in the figures. Furthermore, the fact that the fibers 34B extend along the axial direction does not mean that the fibers 34B extend strictly parallel to the axial direction, but rather that they may be slightly inclined (intersecting) relative to the axial direction due to the nature of the fibers 34B.

[0038] Furthermore, fibers 34B are not limited to fibers having a length dimension in the axial direction of tubular body 34A, but may be fibers shorter than the axial length dimension of tubular body 34A, and may be distributed in the circumferential, radial, and axial directions so that the fibers overlap each other in the axial direction.

[0039] The end member 36 is formed as a cylindrical body and includes an inner tube fixing portion 37 for fixing the inner tube 32, an outer tube fixing portion 38 for fixing the outer tube 34, and a unit connecting portion 39 for connecting to other units. The end member 36 can be made of, for example, resin, hard rubber, metal, etc. Preferably, the end member 36 is made of a lightweight material.

[0040] The inner tube fixing portion 37 is provided on one end side of the inner peripheral surface of the end member 36 so that the outer periphery of the inner tube 32 can be fitted thereto. In this embodiment, since the inner tube 32 has a spiral bellows structure, for example, the inner tube fixing portion 37 can utilize the spiral shape of the inner tube 32 to form a spiral groove into which the outer periphery of the inner tube 32 can be screwed and fixed. Hereinafter, in the axial direction of the end member 36, the side where the inner cylinder fixing portion 37 is provided will be referred to as the inside, and the opposite side will be referred to as the outside.

[0041] When the inner tube fixing portion 37 is formed as a spiral groove, it is preferable to screw in the spiral ridge portion at least one pitch on the outer periphery of the inner tube 32, taking into consideration the airtightness with the inner tube 32. Also, by forming the inner tube fixing portion 37 to provide an interference fit when the inner tube 32 is screwed in, for example, the outer periphery of the inner tube 32 comes into close contact with the inner tube 32, thereby improving the airtightness between the end member 36 and the inner tube 32.

[0042] The fixing of the inner tube 32 to the end member 36 is not limited to the above embodiment, and may be modified as appropriate depending on the shape of the inner tube 32, etc., so that the inner tube 32 is fixed to the end member 36 in an airtight state.

[0043] The outer tube fixing portion 38 is provided on the outer peripheral surface of the end member 36. The outer tube fixing portion 38 is located a predetermined distance axially outward from the end face of the inner tube 32 fixed to the inner tube fixing portion 37. The outer tube fixing portion 38 is formed, for example, in a spherical or tapered shape so that the outer diameter gradually decreases as it goes axially outward around the outer periphery of the end member 36.

[0044] The outer tube 36 is fixed to the outer tube fixing portion 38 formed in this manner as follows: The end of the outer tube 34 is inserted into the end member 36 so that it passes the outer tube fixing portion 38 on the axially outer side. A ring-shaped crimping member 42 is placed over the outer peripheral surface of the inserted outer tube 34, and the crimping member 42 is fixed from the axially outer side with a fixing member 43 that can be tightened from the outer peripheral side of the outer tube 34 toward the end member 36, thereby making it possible to fix the end member 36 to the outer tube 34.

[0045] The method of fixing the end member 36 to the outer tube 34 is not limited to the above embodiment, and any method may be used as long as the outer tube 34 is fixed to the end member 36 in an airtight manner.

[0046] By fixing the end members 36;36 to both ends of the inner tube 32 and the outer tube 34 in this manner, a fluid chamber S30 is formed as a closed space surrounded by the outer surface of the inner tube 32, the inner surface of the outer tube 34, and the end members 36;36.

[0047] The unit connecting portion 39 is provided, for example, in a cylindrical shape that is exposed axially outward from the fixing member 43 when the outer cylinder 34 is fixed to the end member 36. By connecting a connecting unit 70 to this unit connecting portion 39, the traction unit 30 can be connected to the gripping unit 10, the traction unit 30, the pushing unit 50, etc. This unit connecting portion 39 is provided with, for example, a pair of through holes 39h that penetrate the end member 36 in the radial direction and are used to fix the connecting unit 70.

[0048] The end member 36 is also provided with a supply / discharge hole 40 that connects the fluid chamber S30 to the outside. The supply / discharge hole 40 is formed, for example, so that one end opens at the inner peripheral surface of the end member 36 and the other end opens at the inner end face of the end member 36 , penetrating through the end member 36 . A supply / discharge hole 40 opening on the inner peripheral surface side of the end member 36 is connected to a tube (not shown) for supplying air to the fluid chamber S30 and discharging the supplied air. The supply / discharge hole 40 may be formed in any manner as long as it is capable of supplying and discharging air from the inner periphery of the end member 36 to the fluid chamber S30.

[0049] FIG. 5(a) shows the traction unit 30 in a contracted state, and FIG. 5(b) shows the traction unit 30 in an expanded state. The contracted state here refers to the state when the fluid chamber S30 is at atmospheric pressure, and the expanded state refers to the state when it is most expanded and there is essentially no friction between it and the inner wall of the pipe Z. The traction unit 30 functions as an actuator that operates by supplying air to the fluid chamber S30, and as shown in Figures 5(a) and 5(b), its length contracts axially from x30 to X30 while its outer diameter expands radially from d30 to D30 (hereinafter, this state will be referred to simply as the expanded state). Furthermore, by discharging air from the fluid chamber S30, the axial length increases from X30 to x30 and the radial outer diameter decreases from D30 to d30, as shown in Figure 5(b) to Figure 5(a) (hereinafter, this state will be referred to simply as the contracted state).

[0050] The dimensions of each part of the towing unit 30 are set so that when expanded, there is virtually no friction between it and the inner wall of the piping Z, i.e., so that the outer diameter D30 when expanded is equal to or smaller than the inner diameter of the piping Z to be inspected.

[0051] [Push / pull force generating part] FIG. 6 is a diagram showing an example of an actuator constituting the pushing / pulling force generating unit 8. As shown in FIG. The pushing / pulling force generating unit 8 is configured by an actuator that operates by air pressure and expands substantially only in the axial direction when compressed air is supplied, and contracts substantially only in the axial direction when the supplied compressed air is discharged. "Expanding substantially only in the axial direction" and "contracting substantially only in the axial direction" mean that radial deformation is restricted, and do not mean that there is no radial deformation, but rather allow some radial deformation and include radial deformation that does not reach at least the inner diameter of the pipe Z. In this embodiment, the pushing / pulling force generating unit 8 will be described as being composed of one actuator. The actuator that composes the pushing / pulling force generating unit 8 will be referred to as a pushing / pulling unit 50.

[0052] As shown in FIG. 6, the pushing unit 50 includes a cylindrical elastic body 52 formed in a cylindrical shape, end members 54 that close openings at both ends of the cylindrical elastic body 52, and a band 56. The pushing unit 50 is configured as a so-called soft actuator in which a closed space S50 is formed, surrounded by the inner periphery of a cylindrical elastic body 52 and an end member 54 inserted into the cylindrical elastic body 52. ​​When air is supplied into the closed space S50, it expands in one direction as shown in Fig. 6(a), and when the supplied air is discharged, it contracts to its pre-expansion state as shown in Fig. 6(b).

[0053] The cylindrical elastic body 52 includes a cylindrical main body 52A made of rubber, fibers 52B oriented in a spiral at a predetermined angle relative to the circumferential direction of the cylindrical main body 52A, and fibers 52C oriented along the circumferential direction. The fibers 52B and 52C are encapsulated in the cylindrical main body 52A.

[0054] For example, one fiber 52B can be used that has a length that reaches from one axial end side to the other axial end side of the cylindrical elastic body 52. ​​Although Fig. 6 shows one fiber 52B, a plurality of fibers may be provided, shifted in position in the circumferential direction. When the cylindrical elastic body 52 is deformed, the fibers 52B restrain the deformation in the extension direction of the fibers 52B. As a result, air is supplied to the closed space S50 of the pushing unit 50, and as the pressure in the closed space S50 increases, the cylindrical elastic body 52 is allowed to stretch in the axial direction (stretching direction) while being restricted from expanding in the radial direction. The fibers 52B are preferably non-stretchable.

[0055] The angle at which the fibers 52B are inclined may be, for example, not less than 0° and less than 30°, more preferably not less than 0° and less than 20°, and even more preferably not less than 0° and less than 10°. As the angle approaches 0°, the cylindrical elastic body 52 becomes more likely to deform in synchronization with the fibers 52B, and therefore, the fibers 52 can be made to easily stretch axially outward while being prevented from stretching radially outward.

[0056] The fibers 52C, for example, have a length shorter than the circumferential length of the cylindrical elastic body 52 and are distributed throughout the cylindrical elastic body 52. ​​This makes it possible to adjust the radial expansion of the cylindrical elastic body 52.

[0057] Therefore, the angle of the fibers 52B in the cylindrical elastic body 52 and the length and distribution of the fibers 52C may be combined according to the extension amount Q required for the pushing unit 50.

[0058] The end members 54 are formed in a cylindrical shape and function as lids that close each end of the cylindrical elastic body 52. ​​The end members 54 can be made of materials such as resin, hard rubber, or metal. Preferably, the end members 54 are made of a lightweight material.

[0059] A groove (not shown) is formed around the circumference of the end member 54. The end member 54 is fixed to the cylindrical elastic body 52 by inserting the cylindrical elastic body 52 so that the cylindrical elastic body 52 covers the groove and tightening a band 56 from the outer periphery of the cylindrical elastic body 52 at a position corresponding to the groove.

[0060] The end member 54 includes a unit connecting portion 59 that protrudes axially outward when attached to the cylindrical elastic body 52 . The unit connecting portion 59 is formed, for example, in a cylindrical shape, and is provided with a pair of through holes 59h that penetrate the end member 54 in the radial direction. The unit connecting portion 59 and the through holes 59h are used to fix the connecting unit 70. By connecting the connecting unit 70 to the unit connecting portion 19, the gripping unit 10 can be connected to the gripping unit 10, the towing unit 30, the pushing unit 50, and the like.

[0061] Each end member 54 is provided with a through hole 62 for passing an air tube (pipe) connected to the gripping unit 10 connected to the pushing unit 50. Also, one of the end members 54 is formed with a supply / discharge hole 60 communicating with the closed space S50. An air tube (pipe) extending from the control device 100 is connected to the supply / discharge hole 60. The through holes 62 provided in each end member 54 and the supply / discharge hole 60 provided in one end member 54 are provided so as to extend in the axial direction. In addition, the air tube (pipe) passing through the through-hole 62 is sealed by a sealing member (not shown) for the through-hole 62 when not in use.

[0062] FIG. 6(a) shows the pushing unit 50 in its natural state, and FIG. 6(b) shows the pushing unit 50 in its extended state. The natural state here means a state in which the fluid chamber S50 is at atmospheric pressure, and the extended state means that the pushing unit 50 is extended in the axial direction from the natural state. The pushing unit 50 functions as an actuator that operates by supplying air to the fluid chamber S50, and as shown in Figure 6(a) to Figure 6(b), its length in the axial direction extends from x50 to X50 (hereinafter, this state will be simply referred to as the extended state). Furthermore, by discharging air from the fluid chamber S50, the axial length increases from X50 to x50 as shown in FIG. 6(b) to FIG. 6(a) (hereinafter, this state will be simply referred to as the contracted state). The expansion / contraction amount Q shown in the figure does not indicate the actual length, but merely indicates the change in the operation of the pushing unit 50. In the pushing unit 50, the expansion amount Q, which is the expansion of the axial length from X50 to x50, is set to be sufficiently larger than the expansion / contraction amounts in the axial direction of the gripping unit 10 and the traction unit 30 described above.

[0063] The material of the fibers 14B, 34B, 52B contained in the outer tube 14 of the gripping unit 10, the outer tube 34 of the traction unit 30, and the tubular elastic body 52 of the pushing unit 50 is preferably a material that exhibits little axial expansion and contraction change. For example, stretchable materials such as aramid fiber, carbon fiber, glass fiber, nylon, polyamide fiber, polyolefin fiber, and metal fiber can be appropriately selected and used. Furthermore, the adhesiveness can be sufficiently improved by subjecting the fibers 14B, 34B, and 52B to an appropriate primer treatment or surface oxidation treatment, but it is preferable to select the treatment depending on the adhesiveness to rubber.

[0064] The fibers 14B, 34B, and 52B may be in any form, such as filaments, yarns (spun yarns and filament yarns), or strands. Furthermore, it is also possible to use untwisted fibers that are bundled without twisting, or fibers made by twisting multiple fibers of such fibers. Depending on the type of fiber, it is also possible to combine two or more fibers made of different materials or different forms.

[0065] Furthermore, the shape of the fibers 14B, 34B contained in the outer tube 14 of the holding unit 10 or the outer tube 34 of the traction unit 30 may be set appropriately taking into consideration the responsiveness of the holding unit 10 or the traction unit 30 when expanding from a contracted state or contracting from an expanded state. Furthermore, the shape of the fibers 52B contained in the cylindrical elastic body 52 of the pushing unit 50 may be set appropriately taking into consideration the responsiveness of the pushing unit 50 when it expands from a contracted state or when it contracts from an expanded state.

[0066] In addition, the thickness of the outer tube 14 of the gripping unit 10, the tube body 34A containing the fibers 34B of the traction unit 30, and the tube body 52A containing the fibers 52B of the pushing unit 50, as well as the elastic material used, can be set according to the performance required for each unit 10; 30; 50.

[0067] Furthermore, the working medium (fluid) for operating the gripping unit 10, the towing unit 30, and the pushing unit 50 is air, but is not limited to this and may be other gases such as inert gases or fluids such as water. In this case, it is sufficient to appropriately configure the gripping unit 10, the towing unit 30, and the pushing unit 50 with a device that can supply or discharge the fluid depending on the fluid used.

[0068] [About connecting units] FIG. 7 is an external view of the connecting unit 70. As shown in FIG. The connecting unit 70 enables the connection of the gripping unit 10, the towing unit 30, the pushing unit 50, and the like. The device includes a pair of cylindrical fixed bodies 71 fixed to the gripping unit 10, the traction unit 30, the pushing unit 50, etc., a connecting ring 72 connecting the cylindrical fixed bodies 71 together, and a coil spring 73.

[0069] The cylindrical fixture 71 includes a cylindrical portion 74 and connecting pieces 75, 75. The cylindrical portion 74 is formed in a cylindrical shape having an inner diameter large enough to allow insertion of an end member, for example, so as to be in sliding contact with the outer periphery of a unit connecting portion provided on the end member of the gripping unit 10, the traction unit 30, or the pushing / pulling unit 50.

[0070] The connecting piece 75 is provided integrally with the tubular portion 74, and is formed as a plate piece extending rearward along the axial direction from one end of the tubular portion 74 so as to be continuous with the outer circumferential surface of the tubular portion 74. A pair of connecting pieces 75 are provided at positions offset by 180 degrees in the circumferential direction of the tubular portion 74, i.e., so as to face each other in the radial direction and extend the same length.

[0071] The connecting piece 75 has a connecting hole 75A on the tip side. The connecting hole 75A is provided as, for example, a circular hole. The connecting holes 75A, 75A provided in each connecting piece 75, 75 are formed so that their centers are coaxial.

[0072] The cylindrical portion 74 also has a pair of connecting holes 74A; 74A on the other end opposite to the extension of the connecting piece 75. The pair of connecting holes 74A; 74A are formed as circular holes that penetrate radially through the cylindrical portion 74. The pair of connecting holes 74A; 74A function as one of the elements that constitute the fixing means when fixing the cylindrical fixing body 71 to each unit 10; 30; 50.

[0073] The connecting ring 72 is configured as an annular member having an outer diameter that allows it to be held between the connecting pieces 75 , 75 provided on the cylindrical fixed body 71 . The connecting ring 72 has a plurality of connecting holes 72A that enable connection to the two cylindrical fixing bodies 71; 71. The connecting holes 72A are provided as four holes that penetrate the connecting ring 72 in the thickness direction at equal intervals in the circumferential direction.

[0074] The pair of cylindrical fixing bodies 71 are attached to the connecting ring 72 as follows. One of the cylindrical fixed bodies 71 is positioned so that the connecting ring 72 is sandwiched between the connecting pieces 75;75, the connecting holes 72A;72A of the connecting ring 72 are overlapped with the connecting holes 75A;75A provided in the connecting pieces 75;75, and an axial member 76 is inserted into each of the overlapping connecting holes 72A;75A so that it cannot fall off, thereby allowing the connecting ring 72 to be freely rotatably attached between the connecting pieces 75;75 of one of the cylindrical fixed bodies 71.

[0075] In addition, the other cylindrical fixed body 71 is positioned so that the connecting ring 72 is sandwiched between the connecting pieces 75;75, and the remaining connecting holes 72A;72A of the connecting ring 72 are overlapped with the connecting holes 75A;75A provided in the connecting pieces 75;75, and the shaft members 66 are inserted into each of the overlapping connecting holes 72A;75A so that they cannot fall out, thereby allowing the connecting ring 72 to be freely rotatably attached between the connecting pieces 75;75 of the other cylindrical fixed body 71. As a result, in other words, the connecting unit 70 is configured to be operable as a hollow so-called universal joint by connecting the two cylindrical fixing bodies 71 and the connecting ring 72.

[0076] 7(a) and (b), the coil spring 73 is disposed in the hollow space on the inner periphery formed by the two cylindrical fixed bodies 71, 71 connected as described above, and the connecting ring 72. For example, the outer diameter of the coil spring 73 is set to a size that allows it to pass through the inner periphery of the connecting ring 72, and the end portion on one end side and the end portion on the other end side are attached so as to seat on spring seats (not shown) provided on the cylindrical fixed body 61.

[0077] As described above, by forming the cylindrical fixing bodies 71 and the connecting ring 72 into a ring shape, the connecting unit 70 can maintain a continuous hollow space inside the connected units when connecting the gripping unit 10 and the traction unit 30, the traction units 30 together, or the gripping unit 10 and the pushing unit 50, etc. This allows the passage of tubes, cables, etc. for supplying and discharging air to and from each unit 10, 30, 50.

[0078] Furthermore, by providing a coil spring 73 in the inner space formed by the cylindrical fixed bodies 71; 71 and the connecting ring 72 that constitute the connecting unit 70, the connecting unit 70 can maintain a hollow state while allowing one cylindrical fixed body 71 to bend relative to the other cylindrical fixed body 71 (operating as a universal joint), and the elasticity of the coil spring 73 can provide a restoring force to this bending. Although not shown, a cover is attached to the connecting unit 70 to cover the outer periphery from one cylindrical fixed body 71 to the other cylindrical fixed body 71. The cover should be made of a material that does not hinder bending and can prevent foreign matter such as dust and water from entering the inside, such as elastic and waterproof material such as rubber.

[0079] The attachment of the connecting unit 70 to the gripping unit 10, the towing unit 30, and the pushing unit 50 will be explained using the gripping unit 10. The end member 16 of the gripping unit 10 is inserted into the tubular portion 74 of one of the tubular fixed bodies 71. Then, the coupling holes 74A, 74A provided in the tubular portion 74 are aligned with the through-hole 19h provided in the unit connecting portion 19 of the end member 16, and an unillustrated shaft member is inserted into the overlapping coupling hole 74A and through-hole 19h so that it cannot fall off, thereby fixing the gripping unit 10 to one of the tubular fixed bodies 71. The traction unit 30 and pushing unit 50 can be similarly coupled to the other tubular fixed body 71. As a result, the gripping unit 10 and the towing unit 30, the towing units 30, and the gripping unit 10 and the pushing unit 50 connected via the connecting unit 70 are connected in a flexible manner.

[0080] [About unit support members] FIG. 8 is a diagram showing an example of the unit support member 80. As shown in FIG. The unit support member 80 according to this embodiment includes a base 81 and a fiber group 83, and functions as a centering means for arranging the axis of extension and contraction of each unit 10; 30; 50 in the vicinity of the center line of the pipe Z.

[0081] 8, the base 81 is configured, for example, as a flat semicircular member whose inner peripheral surface extends in a semicircular arc shape along the outer peripheral shape of the end member 16, 36, 54 of each unit 10, 30, 50 so that it can be attached along the outer periphery of the end member 16, 36, 54 of each unit 10, 30, 50. The base 81 is formed so as to have a constant width in the axial direction along the circumferential direction when attached to the end member 16, 36, 54 of each unit 10, 30, 50.

[0082] When the unit support member 80 is viewed in a plane, the fiber group 83 is implanted at a predetermined density in the circumferential and axial directions on the outer surface of the base 81 so that multiple fibers 83z extend radially from the center of the inner circumference of the semicircular base 81, for example, to form a brush.

[0083] The unit support members 80 are formed in a semicircular shape and are attached in pairs so that the fibers 83z are arranged all the way around the outer periphery of the end members 16, 36, 54 of each unit 10, 30, 50. In other words, the unit support members 80 can also be said to be a partitioning means that partitions the piping Z into front and rear in the traveling direction at the position where the unit support members 80 are provided in the inspection section 2.

[0084] Preferably, the length of each fiber 83z constituting the fiber group 83 is set so that, for example, when the central axis of each unit 10; 30; 50 is coaxial with the central axis of the pipe Z, the tip thereof is in sliding contact with the entire inner wall of the pipe Z.

[0085] More preferably, the material, thickness, and planting density of the fibers 83z constituting the fiber group 83 are set so that the central axis of each unit 10; 30; 50 is positioned coaxially with the central axis of the pipe Z.

[0086] The fiber group 83 is not limited to having its tip in sliding contact with the inner wall of the pipe Z over the entire circumference, but may have its tip in sliding contact with at least the lower inner wall of the pipe Z, for example. The material of the fiber 83z is preferably a material having elasticity and stiffness, such as nylon fiber.

[0087] Furthermore, the unit support member 80 is not limited to the fiber group 83, and may be made of other materials such as rubber or resin. In this case, it is preferable that the unit support member 80 is made of a material that does not interfere with the propulsive force obtained by the propulsive force generating means 8. Furthermore, the unit support member 80 is not limited to the circular shape described above, and the outer shape as viewed in the axial direction may be appropriately set in accordance with the cross-sectional shape perpendicular to the extension direction of the pipe Z.

[0088] The control device 100 includes a compressor 102 that generates compressed air to be supplied to each unit 10; 30; 50, a regulator 104 that adjusts the compressed air output from the compressor 102 to a predetermined pressure, a solenoid valve 106 that controls the supply of compressed air to each unit 10; 30; 50 and the discharge of compressed air supplied to each unit 10; 30; 50, and a controller 108 that controls the operation of the solenoid valve 106.

[0089] The solenoid valve 106 has an input port connected to the regulator 104, an output port connected to each of the units 10, 30, and 50, and an exhaust port communicating with the atmosphere. A three-way valve can be used that includes a flow path (hereinafter referred to as a supply path) that connects an input port and an output port, a flow path (hereinafter referred to as a discharge path) that connects the output port and an exhaust port, and a valve that switches between the supply path and the discharge path based on an electrical signal.

[0090] The solenoid valve 106 is electrically connected to the controller 108, and operates the valve based on a signal input from the controller 50 to switch between the supply path and the discharge path. In this embodiment, the solenoid valve 106 will be described as closing the supply path and opening the discharge path when no signal is input, and opening the supply path and closing the discharge path when a signal is input. One end of a tube for supplying compressed air to each unit 10, 30, and 50 is connected to the output port of the solenoid valve 106. The other end of the tube is connected to each unit 10, 30, and 50. That is, the flow paths from the output ports of the solenoid valves 106 to the respective units and the closed spaces S10, S30, S50 in the respective units are kept in communication regardless of the operation of the solenoid valves 106.

[0091] The controller 108 is a so-called computer that includes hardware resources such as a processing unit such as a CPU (processor), storage units such as a ROM and a RAM, and external input units that enable connection with sensors and external devices. The storage means stores a program for operating each of the units 10, 30, and 50 in a predetermined order. The controller 108 controls the supply and discharge of compressed air to each of the units 10, 30, and 50, for example, by controlling the solenoid valves 106 provided corresponding to each of the units 10, 30, and 50 using PWM control.

[0092] FIG. 9 is a diagram showing an example of the propulsion operation of the moving body 2. As shown in FIG. 9(a) shows the initial state in which the moving body 2 is placed in the piping Z. The initial state means that the gripping units 10A, 10B, 10C, the three traction units 30, and the pushing unit 50 are in their natural states (natural lengths). (Step 1): To propel the moving body 2, first, as shown in FIG. 9(b), compressed air is supplied to the gripping unit 10B, which is expanded until a predetermined friction is achieved with the inner wall of the pipe Z. At this time, the gripping units 10A, 10C, the three traction units 30, and the pushing unit 50 maintain their natural states. This fixes it to the pipe Z. (Step 2): Next, as shown in Fig. 9(c), while maintaining the expanded state of the gripping unit 10B, compressed air is supplied to the pushing unit 50 to extend the pushing unit 50. At this time, the gripping units 10A, 10C and the three traction units 30 maintain their natural states. As a result, the gripping unit 10A of the moving body 2 is pushed deeper into the pipe Z by the extension of the pushing unit 50. (Step 3): Next, as shown in Fig. 9(d), while maintaining the expanded state of the gripping unit 10B and the extended state of the pushing unit 50, compressed air is supplied to the gripping unit 10A to expand the gripping unit 10A. At this time, the gripping unit 10C and the three traction units 30 maintain their natural states. By this operation, the moving body 2 is fixed by the gripping units 10A and 10B with the pushing unit 50 extended. (Step 4): Next, as shown in Fig. 9(e), while maintaining the expanded state of the gripping units 10A and 10B and the extended state of the pushing unit 50, compressed air is supplied to the three traction units 30 to expand the three traction units 30. At this time, the gripping unit 10C maintains its natural state. This operation causes the three traction units 30 to contract in the axial direction, pulling the rear end of the moving body 2 forward. At this time, the wiring H (air tube (pipe) for supplying and discharging air to each unit) extending rearward from the rear gripping unit 10C is pulled forward. (Step 5): Next, as shown in FIG. 9(f), while maintaining the expanded state of the gripping units 10A, 10B and the three traction units 30, and the extended state of the pushing unit 50, compressed air is supplied to the gripping unit 10C to expand the gripping unit 10C. By this operation, the moving body 2 is fixed to the pipe Z by all of the gripping units 10A, 10B, and 10C, and the position at which the moving body 2 is fixed within the pipe Z can be changed. (Step 6): Next, as shown in FIG. 9(g), while maintaining the expanded state of the gripping units 10A and 10C, the compressed air supplied from the gripping unit 10B, the three traction units 30, and the pushing unit 50 is discharged, contracting the gripping unit 10B and the three traction units 30 and shortening the pushing unit 50. With this operation, the moving body 2 is fixed by the front gripping unit 10A and the rear gripping unit 10C. At this time, between the gripping unit 10A and the gripping unit 10C, the gripping unit 10B and the three traction units 30 extend in the axial direction, and the pushing unit 50 contracts in the axial direction. In addition, due to the compressed air being discharged from the pushing unit 50, the restoring force of the pushing unit 50 acts as a pulling force in the forward direction in the extension of the gripping unit 10B and the three traction units 30. (Step 7): Next, as shown in FIG. 9(h), while maintaining the expanded state of the gripping units 10A; 10C, the contracted state of the three traction units 30, and the shortened state of the pushing unit 50, compressed air is supplied to the gripping unit 10B to expand the gripping unit 10B. By this operation, the movable body 2 is again fixed to the pipe Z by all the gripping units 10A, 10B, and 10C, making it possible to change the position at which the movable body 2 is fixed within the pipe Z. (Step 8): Next, as shown in FIG. 9(i), while maintaining the expanded state of the gripping units 10A and 10B, the contracted state of the three traction units 30, and the shortened state of the pushing unit 50, the compressed air supplied from the gripping unit 10C is discharged, causing the gripping unit 10C to contract. By this operation, the moving body 2 is fixed to the pipe Z by the gripping units 10A and 10B. (Step 9): Next, as shown in FIG. 9(j), while maintaining the expanded state of the gripping units 10A and 10B, the contracted state of the gripping unit 10C, and the shortened state of the pushing unit 50, compressed air is supplied to the three traction units 30, causing the three traction units 30 to expand. This operation causes the three traction units 30 to contract in the axial direction, pulling the rear end side of the moving body 2 forward. At this time, the wiring extending rearward from the rear gripping unit 10C is pulled forward. (Step 10): Next, as shown in FIG. 9(k), while maintaining the gripping units 10A, 10B and the three traction units 30 in the expanded state and the pushing unit 50 in the contracted state, compressed air is supplied to the gripping unit 10C to expand the gripping unit 10C. By this operation, the moving body 2 is fixed to the pipe Z by all of the gripping units 10A, 10B, and 10C, and the position at which the moving body 2 is fixed within the pipe Z can be changed. (Step 11): Next, as shown in FIG. 9(l), while maintaining the expanded state of the gripping units 10A and 10C, the compressed air supplied from the gripping unit 10B, the three traction units 30, and the pushing unit 50 is discharged, contracting the gripping unit 10B and the three traction units 30 and shortening the pushing unit 50. By this operation, the moving body 2 is fixed by the front gripping unit 10A and the rear gripping unit 10C. At this time, the gripping unit 10B, the three traction units 30, and the pushing unit 50 are expanded in the axial direction between the gripping unit 10A and the gripping unit 10C, and the pushing unit 50 is contracted in the axial direction. At this time, the distance between the gripping unit 10A and the gripping unit 10C is shorter than in step 6, the length by which the gripping unit 10B and the three traction units 30 extend in the axial direction is longer, and the length by which the pushing unit 50 contracts in the axial direction is shorter. (Step 12): Next, as shown in FIG. 9(m), while maintaining the expanded state of the gripping units 10A; 10C, the contracted state of the three traction units 30, and the shortened state of the pushing unit 50, compressed air is supplied to the gripping unit 10B to expand the gripping unit 10B. By this operation, the movable body 2 is again fixed to the pipe Z by all the gripping units 10A, 10B, and 10C, making it possible to change the position at which the movable body 2 is fixed within the pipe Z. (Step 13): Next, as shown in Figure 9(n), while maintaining the expanded state of the gripping units 10A and 10B, the contracted state of the three traction units 30, and the shortened state of the pushing unit 50, the compressed air supplied from the gripping unit 10C is discharged, causing the gripping unit 10C to contract. By this operation, the moving body 2 is fixed to the pipe Z by the gripping units 10A and 10B. (Step 14): Next, while maintaining the expanded state of the gripping unit 10B, the contracted state of the gripping unit 10C, the contracted state of the three traction units 30, and the shortened state of the pushing unit 50, the compressed air supplied from the gripping unit 10A is discharged to contract the gripping unit 10A. This returns the moving body 2 to the state shown in FIG. 9(b).

[0093] That is, the moving body 2 according to this embodiment can move forward in the direction of travel within the pipe Z by repeating steps 1 to 14 as one cycle. In this cycle, the moving body 2 is configured to move forward by performing an action including a so-called earthworm-type peristaltic movement and an inchworm-type peristaltic movement. First, as shown in Figures 9(c) and (d), the pushing unit 50 is extended to imitate the forward movement of an inchworm, and the front gripping unit 10A is moved forward (step 1). Then, the gripping unit 10A is expanded to fix the moving body 2 to the piping Z (step 2), thereby moving the front of the moving body 2 forward with the large propulsive force characteristic of inchworm-type peristaltic movement. 9(d) to 9(n), the units 10B, 10C, and 30 behind the gripping unit 10A repeat an earthworm-like peristaltic movement, starting from the gripping unit 10A, thereby moving the rear of the moving body 2 forward with a large tractive force specific to earthworm-like peristaltic movement. Also, as shown in FIG. 10(g), compressed air is discharged from the pushing unit 50 midway through the start of the earthworm-like peristaltic movement, so that the restoring force of the pushing unit 50, which tries to shorten, constantly acts on each unit behind the pushing unit 50, further increasing the tractive force due to the earthworm-like peristaltic movement. In this way, according to the configuration of the moving body 2 according to this embodiment, by utilizing the advantageous performance of both the earthworm-type peristaltic movement and the inchworm-type peristaltic movement, Great propulsion and traction forces are obtained.

[0094] As described above, by supplying compressed air to the pushing unit 50 and extending it, the front gripping unit 10A can be pushed deeper into the piping Z in step 2. For example, by setting the extension amount of the pushing unit 50 to a large value, it is effective for passing through curved pipe sections in the piping Z, particularly elbow sections that bend at right angles. For example, by making the extension amount Q of the pushing unit 50 longer than the length of the center line of the elbow portion that bends at a right angle, when the pushing unit 50 is extended, the front gripping unit 10A connected to the front of the pushing unit 50 can be pushed into the elbow portion of the piping Z, allowing the gripping unit 10A to pass through reliably.

[0095] Furthermore, as explained in step 6, by discharging the compressed air supplied to the pushing unit 50, the restoring force of the pushing unit 50 can be constantly applied to each unit behind the pushing unit 50.

[0096] In addition, the moving body 2 is equipped with a traction unit 30 (three in this embodiment) behind the pushing unit 50 in the direction of travel, so that the wiring that becomes a load as the moving body 2 travels can be pulled forward in the direction of travel in each cycle.

[0097] Furthermore, as shown in this embodiment, by performing the process of expanding the traction unit 30 twice while extending and retracting the pushing unit 50 once, the wiring that acts as a load can be reliably pulled every cycle, making it possible for the moving body 2 to move long distances. Furthermore, the number of times that the traction unit 30 expands and contracts in one cycle is not limited to two, but may be changed as appropriate according to the expansion / contraction amount Q of the pushing unit 50.

[0098] The moving body 2 described in the above embodiment is configured so that the overall length of the moving body 2 is the shortest, and the numbers of the gripping force generating units 4, traction force generating units 6, and pushing / pulling force generating units 8 are not limited to this and may be changed as appropriate.

[0099] For example, in the above embodiment, the front gripping portion 4A, the intermediate gripping portion 4B, and the rear gripping portion 4C are each described as being configured with one gripping unit 10, but the number of gripping units is not limited to one, and a plurality of gripping units may be provided. Also, the front gripping portion 4A, the intermediate gripping portion 4B, and the rear gripping portion 4C are described as being configured with the same number of gripping units 10, but the number of gripping units may be changed appropriately depending on the position on the moving body 2.

[0100] Furthermore, in the above embodiment, the traction force generating section 6 is configured by three traction units 30, but this is not limitative and the number of units may be one or more, preferably a plurality of units.

[0101] Furthermore, in the above embodiment, the gripping unit 10 constituting the front gripping portion 4A, the middle gripping portion 4B, and the rear gripping portion 4C has been described as expanding radially outward while contracting axially when compressed air is supplied, and expanding axially while contracting radially inward when the supplied compressed air is discharged, but the present invention is not limited to this. For example, the gripping unit 10 may expand to a size that generates friction with the inner wall of the pipe without shortening in the axial direction when fluid is supplied, and contract due to its elasticity when the supplied fluid is discharged without stretching in the axial direction. Alternatively, the gripping units 10 constituting the intermediate gripping portion 4B and the rear gripping portion 4C may be configured to expand radially outward while shortening in the axial direction when compressed air is supplied, and to contract radially inward while stretching in the axial direction when the supplied compressed air is discharged, or the gripping units 10 constituting the front gripping portion 4A may be configured to expand to a size that generates friction with the inner wall of the pipe without shortening in the axial direction when fluid is supplied, and to contract due to their elasticity when the supplied fluid is discharged without stretching in the axial direction.

[0102] Furthermore, in the above embodiment, the traction unit 30 constituting the traction force generating section 6 is described as being configured so that when inflated to its maximum extent, there is substantially no friction between the traction unit 30 and the inner wall of the piping Z, but this is not limited to this. The traction unit 30 constituting the traction force generating section 6 may be the same as the gripping unit 10, which, for example, contracts axially while expanding radially outward when compressed air is supplied, and contracts radially inward while expanding axially when the supplied compressed air is discharged.

[0103] According to the in-pipe mobile robot 1 of this embodiment, the extension section of the moving body 2 is equipped with a push / pull force generating section 8 (pushing unit 50) that has a long axial stroke of the gripping unit 10 and the traction unit 30, and the extension force of this pushing unit 50 provides a large breaking force for clogs (cleaning) inside curved pipes and piping. Furthermore, when the pushing unit 50 contracts, it can pull up the extension of the unit groups 10 and 30 connected behind the pushing unit 50 when they are extended, and at the same time, it can pull the load behind it with its own strong pulling force (the restoring force when the pushing unit 50 contracts). As a result, the restoring force (pulling force) when the pushing unit 50 contracts and the forward pushing force associated with the extension of the unit groups 10 and 30 connected behind the pushing unit 50 can coexist, making it possible for the moving body 2 to move over long distances even in complex piping having many bent pipes.

[0104] By connecting a unit equipped with a camera or the like to the gripping force generating unit 4 (front gripping unit 4A) at the front of the in-pipe mobile robot 1 configured as described above, it is possible to inspect even complex piping with many bent pipe sections over long distances. [Explanation of symbols]

[0105] 1 In-pipe mobile robot, 2 Mobile body, 100 Control device, 4 Gripping force generating part, 4A front gripping part, 4B intermediate gripping part, 4C rear gripping part, 6 traction force generating unit, 8 push / pull force generating unit, 10;10A;10B;10C gripping unit, 30 towing unit, 50 pushing units, 70 connecting units, 80 Unit support member

Claims

1. An in-pipe mobile robot including a mobile body configured to be movable within a pipe and a control device that controls the operation of the mobile body, a gripping force generating section made of an elastic material, which expands to a size that generates friction with the inner wall of the pipe when a fluid is supplied, and contracts due to its elasticity when the supplied fluid is discharged; a traction force generating section made of an elastic material, which expands in the radial direction and contracts in the axial direction of the pipe when a fluid is supplied, and contracts in the radial direction and extends in the axial direction of the pipe when the supplied fluid is discharged; a pushing / pulling force generating section made of an elastic material, which expands substantially only in the tube axis direction when a fluid is supplied, and contracts substantially only in the tube axis direction when the supplied fluid is discharged, The moving body is An in-pipe mobile robot characterized in that, from the front in the direction of travel, a gripping force generating unit, a pushing / pulling force generating unit, a gripping force generating unit, a traction force generating unit, and a gripping force generating unit are connected in this order.

2. The traction force generating unit is a cylindrical elastic body formed in a cylindrical shape; end members for closing openings at both ends of the cylindrical elastic body; By closing the end member, a closed space is formed surrounded by the inner circumferential surface of the cylindrical elastic body and the end member; Equipped with The cylindrical elastic body is a fiber that restrains radial expansion of the cylindrical elastic body when a fluid is supplied into the closed space; 2. The in-pipe mobile robot according to claim 1, wherein the fiber extends in a spiral shape from one end side to the other end side of the cylindrical elastic body.

3. The gripping force generating unit connected to the pushing / pulling force generating unit in the forward direction is When fluid is supplied, the tube expands in the radial direction and contracts in the axial direction.

3. The in-pipe mobile robot according to claim 1, wherein the robot contracts in the radial direction and expands in the axial direction of the pipe by discharging the supplied fluid.

4. The gripping force generating unit connected to the front side of the pushing / pulling force generating unit in the traveling direction is When fluid is supplied, the tube expands in the radial direction and contracts in the axial direction.

3. The in-pipe mobile robot according to claim 1, wherein the robot contracts in the radial direction and expands in the axial direction of the pipe by discharging the supplied fluid.

5. 3. The in-pipe mobile robot according to claim 1, wherein the traction force generating unit expands to a size that generates friction with the inner wall of the pipe when a fluid is supplied thereto.

6. 3. The in-pipe mobile robot according to claim 1, wherein the traction force generating unit expands by a size that does not cause friction with the inner wall of the pipe when a fluid is supplied thereto.

7. The control device expanding the gripping force generating unit connected to the rear of the pushing / pulling force generating unit in the traveling direction, and then extending the pushing / pulling force generating unit; a gripping force generating unit connected in front of the pushing / pulling force generating unit is moved forward, and then the gripping force generating unit connected in front of the pushing / pulling force generating unit is expanded; While maintaining the expanded state of the gripping force generating unit connected in front of the pushing / pulling force generating unit, 3. The intra-pipe mobile robot according to claim 1, wherein a gripping force generating unit connected to the rear of the pushing / pulling force generating unit, a traction force generating unit, and the gripping force generating unit cause the robot to perform peristaltic movements.

Images