JPH09150737A - Circumferentially travelling method for pipe traveling device, and pipe traveling device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent omission of check of a weld line burnt in the pipe circumferential direction, by setting the steering angles for satisfying the specified relationship between driving raveling bodies at the front and at the tail end in the mutual opposite directions, and making the driving traveling bodies travel in the pipe in the circumferential direction. SOLUTION: A circumferential position detection means 500 for detecting the inclination ϕ from the vertical lower part of a steering shaft is provided as an attitude detector, the distance L between a pipe inner wall surface 51 and the position of center of gravity, the weights W1 of driving traveling bodies 10a, 10b, the weights W2 of driven traveling bodies 20a, 20b, the relationship; W=W1+W2, attracting force P of a pair of magnetic attracting ring bodies 13, the attaching width S, and the total attracting force K of permanent magnets per driven traveling body are stored in a storing means 501, the angles are set from the data so as to satisfy the expression; θ1=cos<-1> (W1×L×sinϕ/(SP×L×sinϕ/(SP×+S×W1×cosϕ/2)) and θ2= sin<-1> ((W1×sinϕ×(2×P+K+W×sinϕ)×μ)/(2×F)), and the steering angles θare made in the mutual opposite directions, and the driving traveling bodies travel in the pipe in the circumferential direction.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention changes the pipe diameter and the posture of the pipe (horizontal, vertical), and travels inside a pipe provided with a valve and the like while adhering to a traveling surface in the axial direction of the pipe. The present invention relates to a circumferential traveling method of an in-pipe traveling device to be inspected, and a in-pipe traveling device capable of performing such traveling.

[0002]

2. Description of the Related Art Conventionally, a magnetic attraction force has been used as an in-pipe traveling device that has branches such as teeth and can be applied in a wide range of pipe diameters (for example, 200 A to 600 A) and can travel a long distance (for example, 500 m) Therefore, there is a magnetic wheel type in-pipe traveling device in which a plurality of traveling vehicle bodies traveling in the pipe while being attracted to the inner wall surface of the pipe are connected in series. This in-pipe traveling device is a traveling mechanism that travels with a pair of magnetic attraction wheels provided at both ends of the axle, and a steering mechanism that steers the axle center and directs the magnetic attraction wheel in the pipe axis direction or the pipe circumferential direction, The driving vehicle body equipped with a camera for inspecting the inside of the piping is arranged in the front row and the rearmost, and in the middle, the cable reel necessary for traveling,
It stores equipment such as storage batteries, and attracts it to the inner surface of the pipe with a permanent magnet that is provided in non-contact with the inner wall surface of the pipe, and arranges a driven vehicle body that is pulled by the driving vehicle body and travels with spherical wheels. It is a device connected by a shaft via a 1-degree-of-freedom rotation support mechanism. The steering mechanism adjusts the magnetic attraction wheel body to the pipe axis direction, and runs in the pipe longitudinal direction while observing the pipe condition in front of the pipe with a camera. Then, at the time of inspecting the welding line constructed in the pipe circumferential direction, the steering mechanism rotates the axle center to run the magnetic attraction wheel in the circumferential direction parallel to the pipe circumferential direction.

[0003]

However, since the steering mechanism of the drive traveling vehicle body rotates the center of the axle to steer the magnetic attraction wheel body in parallel with the circumferential direction of the vehicle, the magnetic attraction of the front and rear axles. As shown in FIG. 12, when the wheel body is viewed from the pipe cross-section direction, the magnetic attraction wheel body is apt to support the point at a single point, and the momentary force generated by the weight of the vehicle body itself is not received. Therefore, in the worst case, there was a problem such as falling or overturning. In order to solve the above-mentioned problems, the drive mechanism and steering mechanism of the magnetic attraction wheel body are 4WD and 4WD.
With the WS configuration, the magnetic attraction wheels are steered around the magnetic attraction wheels not at the center of the axle and at right angles to the tube axis, and the support by the magnetic attraction wheels is run in the pipe circumferential direction as two-point support. A method can be considered. However, in order to have the 4WD and 4WS configurations, it is necessary to provide a rotation driving means on the rotation axis of the magnetic attraction wheel body and a steering means on an axis orthogonal to the rotation axis of the magnetic attraction wheel body. In the case of independently controlling the motors, a drive source with a maximum of 8 axes is required, and the structure becomes complicated. Furthermore, the volume and weight of the in-pipe traveling device increase, and it is difficult to provide a drive source in a limited space inside the pipe. In order to solve the above-mentioned problems, the present invention can adopt a method capable of easily traveling in the circumferential direction of the pipe with a simple structure without increasing the volume and weight of the traveling device, and such a method. An object is to provide a traveling device in a pipe.

[0004]

In order to solve the above-mentioned problems, the characteristics and configuration of the circumferential traveling method of the in-pipe traveling device according to the present invention are as follows.

[Structure] That is, the characteristic means of the circumferential traveling method of the in-pipe traveling device according to claim 1 is that a plurality of traveling vehicle bodies traveling in the pipe while being attracted to the inner wall surface of the pipe by magnetic attraction are connected in series. Drive means for adsorbing to the inner wall surface of the pipe by a pair of magnetic attraction wheels provided at both ends of the axle, and driving the pair of magnetic attraction wheels with the magnetic attraction wheels in the longitudinal direction of the vehicle body and the magnetic attraction. A drive traveling vehicle body provided with a pair of traveling bodies provided with steering means for steering around a steering axis perpendicular to the axis of the wheel body, which is divided into a front portion and a rear portion of the vehicle body, and a non-conducting portion with respect to the pipe inner wall surface. The driven traveling vehicle body is provided with a driven vehicle body provided with an adsorbing means for adsorbing to the inner wall surface of the pipe by a permanent magnet provided in contact with the driven traveling vehicle body and traveling means driven by spherical wheels. And place it at the end, In the case where the driven traveling vehicle body is arranged in the middle of each of the traveling vehicle bodies and the traveling vehicle bodies are circumferentially traveled in a circumferential direction, the in-pipe traveling device in which the traveling vehicle bodies are connected by a shaft through a rotation support mechanism having one degree of freedom around the shaft in the vehicle body width direction is used. It is done like this.
That is, the weight of each driving vehicle body is W1, the distance from the inner wall surface of the tube to the center of gravity is L, the attraction force of the pair of magnetic attraction wheels is P, the mounting width is S, and the weight of all the driven vehicles is 2 × W.
2, W = W1 + W2, the total attraction force of the permanent magnet per driven vehicle body is K, the friction coefficient between the inner wall surface of the pipe and the magnetic attraction wheel body is μ, and the running force that can be generated by one driving means in the driving means is F, When the inclination of the steering shaft from below vertically is φ, the absolute value of the steering angle θ with respect to the pipe axis direction is

[Equation 7] θ ≦ cos ⁻¹ (W1 × L × sin φ / (S × P
+ S × W1 × cos φ / 2)) θ ≧ sin ⁻¹ ((W × sin φ + (2 × P + K + W × c
osφ) × μ) / (2 × F)), and the steering angles θ of the front-row and rear-most driving traveling vehicle bodies are set in mutually opposite directions, and the vehicle travels in the pipe in the circumferential direction. .

[Operation and Effect] This in-pipe traveling device is provided with a drive traveling vehicle body at the front row and the rearmost portion of the traveling device, and a driven traveling vehicle body in between. These are connected by a shaft around a shaft in the vehicle width direction via a rotary mechanism having one degree of freedom. Therefore, when the pair of front and rear driving traveling vehicle bodies move in the circumferential direction of the pipe, the driven traveling vehicle body also follows this movement. The in-pipe traveling device moves a plurality of traveling bodies in a pipe axis direction to a predetermined position in a state where each of the traveling vehicle bodies is linearly arranged (schematically shown in FIG. 1 and specifically shown in FIG. 5). come. Then, using the method of the present application, traveling in the pipe circumferential direction is performed. According to this method, the steering angle of the driving traveling vehicle body arranged in the front row and the rearmost row in the in-pipe traveling device (the angle formed by the moving direction of the wheel body with respect to the vehicle body front-rear direction is 0 to 90 degrees). There is a feature in θ. That is, as shown in FIG. 1, the front row and the rearmost row are set in directions opposite to each other even though they have the same predetermined angle. Therefore, as shown in FIG. 1, when the magnetic attraction wheel is driven to rotate by the driving means, the traveling force F1 in the pipe circumferential direction and the traveling force F2 in the pipe axial direction are respectively generated in the traveling vehicle bodies in the front row and the rearmost one. Occur. And
Due to the relationship of the steering angle, the traveling force F2 in the pipe axis direction is canceled between the traveling vehicle bodies in the front row and the rearmost one, and only the traveling force F1 in the pipe circumferential direction remains. Therefore, the in-pipe traveling device can travel in the pipe circumferential direction. Furthermore, in selecting the steering angle, the steering angle is set so as to satisfy the condition shown in Expression 7. In this case, this angle satisfies the condition that a moment force capable of preventing tipping due to the support span of the magnetic attraction wheel body can be obtained and a traveling force in the pipe circumferential direction can be obtained, as will be described later in detail. . As a result, the in-pipe traveling device can perform good traveling in the pipe circumferential direction.

As an in-pipe traveling device capable of performing such traveling in the pipe circumferential direction, in the in-pipe traveling device having the above-mentioned configuration, the inclination φ of the steering shaft from the vertically downward direction is φ.
A circumferential position detecting means for detecting (0 to 180 degrees) is provided,

[Equation 8] θ1 = cos ⁻¹ (W1 × L × sin φ / (S ×
P + S × W1 × cos φ / 2)) upper limit steering angle deriving means for deriving an upper limit steering angle θ1

[Equation 9] θ2 = sin ⁻¹ ((W × sin φ + (2 × P +
K + W × cos φ) × μ) / (2 × F)) and a lower limit steering angle deriving means for deriving a lower limit steering angle θ2, and a steering intermediate between the upper limit steering angle θ1 and the lower limit steering angle θ2 Steering angle setting means for deriving as steering angle, and steering angle setting for setting steering angles θ with respect to the pipe axis direction of the front row and the rearmost driving vehicle body in directions opposite to each other with the absolute value being the derived steering angle Means should be provided. With this arrangement, according to the inclination φ of the steering shaft from below in the vertical direction detected by the circumferential position detecting means,
By the upper limit steering angle deriving means and the lower limit steering angle deriving means, the upper limit steering angle θ1 and the lower limit steering angle θ2 are derived, and a derived steering angle suitable for the posture of the traveling vehicle body is derived from these, and steering of this value is performed. By taking a corner, it is possible to perform good traveling in the pipe circumferential direction.

[Structure] The characteristic means of the circumferential traveling method of the in-pipe traveling device according to claim 3 comprises a traveling vehicle body that travels in the pipe while being attracted to the inner wall surface of the pipe by a magnetic attraction force, and is provided at both ends of the axle. A drive means for adsorbing on the inner wall surface of the pipe by a pair of magnetic attraction wheels and driving the pair of magnetic attraction wheels, and a steering shaft around the steering wheel perpendicular to the longitudinal direction of the vehicle body and the axis of the magnetic attraction wheels. In-pipe traveling apparatus in which traveling bodies having steering means for steering to each other are arranged at front and rear portions of a drive traveling vehicle body, and steering shafts of the respective traveling bodies are distributed in the front-rear direction of the drive traveling vehicle body. When traveling in the circumferential direction, the procedure is as follows. That is, the weight of each driving vehicle body is W1, the distance from the tube inner wall surface to the center of gravity is L, the attraction force of the pair of magnetic attraction wheels is P, the mounting width is S, the tube inner wall surface and the magnetic attraction wheel body. Where μ is the friction coefficient between the driving means and F, the running force that can be generated by the driving means by one driving means is F, and the inclination of the steering shaft from the vertical lower side is φ, the steering angle θ with respect to the pipe axis direction.
The absolute value is

[Equation 10] θ ≦ cos ⁻¹ (W1 × L × sin φ / (S ×
P + S × W1 × cos φ / 2)) θ ≧ sin ⁻¹ ((W1 × sin φ + (2 × P + W1 × c
osφ) × μ) / (2 × F)), and the steering angles θ of the traveling bodies arranged in the front portion and the rear portion are set in mutually opposite directions, It runs in the pipe in the circumferential direction.

[Operation and Effect] The driving traveling vehicle body of the in-pipe traveling device is provided with a pair of traveling bodies at a front portion and a rear portion. The steering angle (angle formed by the moving direction of the wheel body with respect to the vehicle body front-rear direction) θ of the pair of traveling bodies is characteristic. That is, as shown in FIG. 10 and FIG. 11, in the traveling body of the front portion and the rear portion of the single traveling vehicle body, these are set in opposite directions although they are at a predetermined angle. . Therefore, as shown in FIG. 10, when the magnetic attraction wheel body is driven by the driving means, the traveling force F1 in the pipe circumferential direction and the traveling force F2 in the pipe axis direction are generated in the traveling bodies at the front portion and the rear portion, respectively. To do. And
Due to the relationship of the steering angle, the traveling force F2 in the pipe axis direction is canceled between the traveling bodies of the front portion and the rear portion, and only the traveling force F1 in the pipe circumferential direction remains. Therefore, the in-pipe traveling device can travel in the pipe circumferential direction. Further, when the steering angle is selected, if the condition shown in Formula 10 is satisfied, this angle provides a moment force due to the support span of the magnetic attraction wheel body, as will be described later in detail, and further, This satisfies the condition that the running force in the circumferential direction can be obtained. As a result, good traveling in the pipe circumferential direction can be performed.

As an in-pipe traveling device capable of traveling in such a pipe circumferential direction, in the in-pipe traveling device having the above-mentioned configuration, a circumferential position detection for detecting an inclination φ of the steering shaft from vertically below is detected. Equipped with means,

[Equation 11] θ1 = cos ⁻¹ (W1 × L × sin φ / (S
× P + S × W1 × cos φ / 2)), which is an upper limit steering angle deriving means for deriving an upper limit steering angle θ1.

[Equation 12] θ2 = sin ⁻¹ ((W1 × sin φ + (2 ×
P + W1 × cos φ) × μ) / (2 × F)) and a lower limit steering angle deriving means for deriving a lower limit steering angle θ2, and an intermediate value between the upper limit steering angle θ1 and the lower limit steering angle θ2 is derived and steered. The steering angle determining means for deriving the angle θ is provided, and the steering angle θ with respect to the pipe axis direction of the traveling body disposed in each of the front portion and the rear portion has an absolute value which is the derived steering angle and is a reciprocal of the steering angle θ. It suffices to provide a steering angle setting means for setting the steering angle. With this configuration, the upper limit steering angle derivation unit and the lower limit steering angle derivation unit determine the upper limit steering angle θ1 and the lower limit steering angle θ according to the inclination φ of the steering shaft from the vertically downward direction detected by the circumferential position detection unit.
2 is derived, a derived steering angle suitable for the posture of the traveling vehicle body is derived from these, and the steering angle of this value is taken, so that good traveling in the pipe circumferential direction can be performed.

As a result, in any case, since the structure and method are as described above, Since the magnetic attraction wheel is steered with an angle offset with respect to the pipe circumferential direction, the magnetic attraction wheel is supported at two points even in the pipe cross-section direction, and the moment force generated by the traveling vehicle body weight may be received. Therefore, it is possible to travel in the circumferential direction while maintaining a stable posture even if a steering mechanism that rotates the mechanism around a simple axle is adopted. 2. Further, the component force of the traveling force of the magnetic attraction wheel body acts in the pipe axis direction and the pipe circumferential direction. In the case of claims 1 and 2, it is between the front row and the rearmost drive traveling vehicle body, and in the case of claims 3 and 4, it is between the front and rear traveling bodies of a single vehicle body. Since the steering angles are in opposite directions, the traveling force in the circumferential direction can be made appropriate. That is, in the case of claims 1 and 2, the resultant force of the traveling force in the pipe circumferential direction by the magnetic attraction wheels between the front row and the rearmost drive traveling vehicle body acts, and the traveling force in the pipe axis direction is Since the driven traveling vehicle body acts in a pulling-up direction, it becomes possible for the traveling device to integrally travel in the circumferential direction of the pipe. On the other hand, according to claims 3 and 4, the resultant force of the traveling force in the pipe circumferential direction by the magnetic attraction wheel between the traveling bodies of the front portion and the rear portion acts, and the same action and effect can be obtained. .

In such a pipe running apparatus, the upper limit steering angle θ1 and the lower limit steering angle θ2 described above are functions of the steering shaft inclination φ, respectively. In the case corresponding to claims 1 and 2 (when adopting the structure shown in FIGS. 1 and 5), W, W1, W2, P, K, L,
An example of a case where a predetermined set of values is adopted as F and S is
This is shown in FIGS. In the figure, the horizontal axis represents the inclination φ of the steering shaft from the vertical direction, and the vertical axis represents the steering angle. Then, the solid line shows the changing situation of the upper limit steering angle θ1, and the broken line shows the changing situation of the lower limit steering angle θ2. In FIG. 4B, the actual steering angle set value is shown as an average value of the upper limit steering angle θ1 and the lower limit steering angle θ2 (this is one of the derived steering angles). The change is indicated by a chain double-dashed line. As can be seen from such a figure, the steering angle should be originally selected as a value related to the inclination φ, and in this way, while changing the steering angle in accordance with the change of φ, traveling It is preferable to run the device in the circumferential direction, which gives the most stable running condition. Here, in the case where the traveling device travels in the circumferential direction while changing the steering angle in accordance with the change of φ, the upper limit steering angle θ1 and the lower limit steering angle θ2 described so far are detected. It is preferable that the steering angle is determined with φ as a reference and a value between these values is set.

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment of a pipe circumferential direction traveling method for a pipe traveling device according to the present invention will be described based on the drawings.
FIG. 1 shows a conceptual diagram of a traveling method in a pipe circumferential direction and a steering angle setting system diagram, and FIGS. 2 and 3 are relationship diagrams of a steering angle. FIG. 5 is a side view of a pipe traveling device. FIG. 7 is a sectional view of the steering mechanism. FIG. 7 is a sectional view of the steering mechanism. FIG. 8 is a bottom view of the driven traveling vehicle body. FIG. 9 is an adsorption action diagram of the driven traveling vehicle body. . First, the configuration of the in-pipe travel device 1 will be described. In FIG. 5, the in-pipe traveling device 1 includes drive traveling vehicle bodies 10a and 10b each having a pair of magnetic attraction wheels 13 on both ends of the axle 12 at the front row and the rearmost row, a spherical wheel 21 and an in-pipe 5 in the middle.
Permanent magnet 22 that is attached in a non-contact manner to the wall surface 51 of 0
And a driven traveling vehicle body 20a, 20b each including a vehicle body 10a-20a, 20a-20b,
20b-10b are connected by a connecting rod 31 via a bearing 30 which is rotatable around an axis in the width direction of the vehicle body and run in the pipe 50 while adsorbing to the wall surface 51 of the pipe 50. Further, in the driving traveling vehicle bodies 10a and 10b, the inside of the pipe 5 is provided at the tip of the vehicle body.
Camera 1 for checking and observing the situation and welding line in front of 0
1, a traveling mechanism 14 that rotationally drives the axle 12, a steering mechanism 15 that steers the axle, a posture detector 16 that detects the posture of the driving traveling vehicles 10a and 10b, a microcomputer,
A control device 17 which includes a driver and processes detection information of each sensor and controls each motor is provided.
Further, the driven traveling vehicle body 20a is provided with a storage battery 23 for supplying electric power to the main body of the in-pipe traveling apparatus 1 or each motor, and the driven traveling vehicle body 20b is connected to a monitoring control device provided on a ground portion (not shown). A cable reel 26 that winds up and sends out the optical cable 25, and a driver 27 that incorporates E / O and O / E that convert the signal form to be transmitted and that drives a motor that drives the cable reel 26 are provided. Further, a Teflon sheet 28 is provided over the side surfaces, the bottom surface, and the side surfaces of the main bodies of the driven traveling vehicle bodies 20a and 20b. In FIG. 6, the traveling mechanism 14 includes a traveling motor 71 and a traveling speed reducer 72 which are housed in the traveling mechanism case 70. The power from the traveling motor 71 travels along with the output shaft of the traveling motor 71 and the traveling motor 71. Pair of gears 73 meshing with the input shaft of the speed reducer 72-traveling speed reducer 72-a pair of gears 74 meshing with the output shaft of the speed reducer 72 for running and the axle 12
Is communicated. A magnet 75 is built in the axle 12 and is connected to the magnetic attraction wheel body 13. The magnetic attraction wheel body 13 is composed of an inner wheel body 80 and a hollow outer wheel body 81 that accommodates the inner wheel body 80 and is mutually movable, and the magnetic force of the magnet 75 causes the inner wheel body 80 and the hollow outer wheel body 81 to move. The driving traveling vehicle bodies 10a and 10b can be attracted by being guided to the inner wall surface 51 of the pipe via the driving shaft, and the driving motor 71 can be driven to drive the axle 12
The magnetic attraction wheel body 13 is rotated via this and can travel in the pipe 50. At this time, the traveling distance of the driving traveling vehicle bodies 10a and 10b is detected by processing the signal of the hall sensor provided in the traveling motor 71 and detecting the number of revolutions of the traveling motor 71. In FIG. 7, the steering mechanism 15 is composed of a steering motor 91 and a steering speed reducer 92 which are built in a steering mechanism case 90, and the power from the steering motor 91 is applied to the output shaft of the steering motor 91 and the steering shaft. Pair of gears 93 meshing with the input shaft of the speed reducer 92 for steering-Speed reducer 92 for steering-
It is transmitted to the traveling mechanism case 70 attached to the output shaft of the steering speed reducer 92. Furthermore, a steering angle detector 930 that detects the amount of rotation of the output shaft of the steering reduction gear 92, that is, the steering angle is provided in the steering mechanism case 90, and is connected by a pair of gears 94 that mesh with the output shaft of the steering reduction gear 92. ing. By driving the steering motor 91, the entire traveling mechanism 14 can be steered, and the magnet attraction wheel body 13 can be oriented in the pipe axis direction or the pipe circumferential direction. Further, the steering angle of the magnetic attraction wheel body 13 with respect to the driving traveling vehicle bodies 10 a and 10 b is detected by the steering angle detector 930. As described above, the pair of magnetic attraction wheels 13 on both ends of the axle 12 attract the inner wall surface 51 of the tube to drive the magnetic attraction wheels 13 and the magnetic attraction wheels 13. A mechanism provided with a steering means for steering around the axis perpendicular to the longitudinal direction of the traveling vehicle body and the axis of the magnetic attraction wheel is called a traveling body. These traveling bodies are distributed and evenly arranged on the center in the width direction of the drive traveling vehicle bodies 10a and 10b, in the front portion and the rear portion of the vehicle body. Furthermore, the steering mechanism 15 described above
The steering shaft Z (see FIG. 1, FIG. 2, and FIG. 7) in the vehicle is on this center line, and the center of the axle 12 (this axle 12
It is provided at the center position of the pair of magnetic attraction wheels 13 provided in. Further, the disposing direction of the steering axis Z coincides with the vertical direction of the driving traveling vehicle body.

In FIG. 8, a suitable number of spherical wheels 21 are provided under the driven vehicles 20a and 20b.
A thin cylindrical permanent magnet 22 built in the magnet case 100 is mounted between the spherical wheels 21 on the wall surface 5.
1, a proper number (three in the embodiment) are attached with a gap provided, and the magnetic force of the permanent magnet 22 can pass through the wall surface 51 and attract the driven vehicle bodies 20a and 20b as shown in FIG. Although the magnetic force of the permanent magnet 22 becomes weaker in proportion to the square of the gap, the wall having the largest cross-sectional area of the permanent magnet 22 (the surface having the largest magnetic force) is formed on the wall surface 5.
Since it is opposed to 1, sufficient suction force can be obtained. Further, since the Teflon sheet 28 is attached to the surface of the permanent magnet 22, it is possible to prevent rust from adhering to the inside of the pipe 50. By configuring the suction means and the traveling means of the driven traveling vehicle bodies 20a and 20b as described above, traveling in the pipe axial direction or the pipe circumferential direction is driven without the need for a steering mechanism.
It becomes possible by being pulled by a and 10b, and can be attracted by the thin cylindrical permanent magnet 22, so that the driven vehicle bodies 20a and 20b can have a low floor structure and the vehicle body space can be maximized to travel a long distance. Therefore, the necessary and sufficient storage battery 23 can be mounted.

Next, a traveling method in the pipe circumferential direction of the in-pipe traveling device configured as described above will be described. As shown in FIG. 1, the steering mechanism 15 of the front-most driving traveling vehicle body 10a and the rearmost driving traveling vehicle body 10b causes θ degrees in a direction in which the frontmost row and the rearmost magnetic adsorption wheels are opposite to the tube axis. Manipulate. The range that the steering angle θ can take is determined by the following conditions. 1) Support span of magnetic attraction wheel body In order to receive a moment force generated by the weight W1 of the drive traveling vehicle body 10a, 10b, it is necessary to provide spans d on the left and right magnetic attraction wheel bodies 13 and support them at two points. . 2, the maximum moment force M is L, the distance from the pipe wall surface (travel surface) to the position of the center of gravity of the driving traveling vehicle bodies 10a and 10b, and φ is the inclination of the steering shaft, which is the inclination from below the traveling vehicle body in the vertical direction. if,

[Expression 13] M = W1 × sin φ × L On the other hand, the required span d to support it
If the attraction force generated by the magnet 75 is P, the magnet 75 is located in the front-rear axis, and therefore, the driving traveling vehicle bodies 10a and 10b.
2 × P / 2 (see FIG. 2), and since the center of gravity of the driving traveling vehicle body is at the midpoint of span d,

## EQU14 ## d ≧ M / (2 × P / 2 + W1 × cos φ / 2) = W1 × L × sin φ / (P + W1 × cos φ / 2) Further, the span d is a function of the steering angle θ, and if the mounting width of the magnetic attraction wheel body 13 is S,

(15) There is a relationship of d = Scos θ. Therefore, the condition of the steering angle θ for receiving the moment force by the support span of the magnetic attraction wheel body 13 is as follows.

[0015]

[Equation 16] θ ≦ cos ⁻¹ (W1 × L × sin φ / (S ×
P + S × W1 × cosφ / 2))

## EQU1 ## The driven vehicles 20a, 20
b is arranged at a position that supports the spherical wheel 21 at two points, and the attraction force of the permanent magnet 22 and the mounting span of the spherical wheel 21 can receive the moment force of the driven traveling vehicle bodies 20a and 20b. 2) Pipe circumferential traveling force by magnetic attraction wheel body The traveling force of the magnetic attraction wheel body 13 acts in the pipe axis direction and the pipe circumferential direction, and the traveling force in the pipe circumferential direction is the driving traveling vehicle body 10a, 1a.
0b and the own weight of the driven traveling vehicle bodies 20a and 20b, and the force acting by the attraction force of the permanent magnet 22 and the magnet 75 must be equal to or more than the resistance force. Maximum resistance R
Is the weight of each of the driven vehicles 20a and 20b.
(2 × W2 in total), K is the total attractive force of the permanent magnet 22 per driven vehicle body, and μ is the friction coefficient,

## EQU17 ## R = 2 × (W1 + W2) × sin φ + 2 ×
It is represented by (2 × P + K + (W1 + W2) × cos φ) × μ. On the other hand, the required traveling force Fp in the pipe circumferential direction for driving the driving shaft is the frontmost row and the rearmost driving shaft, where F is the driving force obtained from the motor torque, the reduction ratio and the radius of the magnetic attraction wheel body 13. Because there are a total of four,

[Expression 18] Fp = 4 × F1 = 4 × Fsin θ, and the condition of the steering angle θ for obtaining the running force Fp in the pipe circumferential direction that is equal to or greater than the resistance R is:

Since Fp ≧ R,

[Equation 20] θ ≧ sin ⁻¹ ((W × sin φ + (2 × P +
K + W × cos φ) × μ) / (2 × F)).

3) FIG. 3 illustrates the above relationship when φ = 90 degrees. The horizontal axis represents the steering angle θ, the vertical axis represents the support span d, and the running force Fp in the pipe circumferential direction. The steering angle θ is the upper limit θ1 of the steering angle determined by the moment force.
And the angle between the lower limit value θ2 of the steering angle determined by the resistance force. Therefore, in the in-pipe traveling apparatus of the present application, as shown in FIG. 1, as one kind of the attitude detector 16 described above,
A circumferential position detecting means 500 for detecting the inclination φ of the steering shaft from below in the vertical direction is provided. Furthermore, in the control device 17 described above, L, W1, W2, W, P,
A storage unit 501 that stores the values of S and K is provided, and from the inclination φ detected by the circumferential position detection unit 500 and the data stored in the storage unit 501,

[Equation 21] θ1 = cos ⁻¹ (W1 × L × sin φ / (S
× P + S × W1 × cos φ / 2)) The upper limit steering angle derivation means 502 for deriving the upper limit steering angle θ1 represented by

[Equation 22] θ2 = sin ⁻¹ ((W × sin φ + (2 × P
+ K + W × cos φ) × μ) / (2 × F)) The lower limit steering angle deriving means 503 for deriving the lower limit steering angle θ2, and the upper limit steering angle θ1 and the lower limit steering angle θ2.
A steering angle determining means 504 for deriving an intermediate value (average value in the case shown) as a derived steering angle is provided, and a steering angle θ with respect to the pipe axis direction of the front row and the rearmost drive traveling vehicle bodies 10a, 10b is The steering angle setting means 505 is provided for setting the derived steering angle in an absolute value in mutually opposite directions.
By adopting such a structure, the setting command of the steering angle setting means 505 is output to each steering mechanism 15. Here, the storage means 501 and the upper limit steering angle derivation means 50
2, lower limit steering angle derivation means 503, steering angle determination means 50
4. The steering angle setting means 505 controls the setting of the steering angle θ with respect to the pipe axis direction of the traveling body based on the inclination φ detected by the circumferential position detecting means 500.
As shown in FIG. 5, the traveling body steering angle control means 510 is collectively referred to. With this configuration, the steering angle is obtained in a predetermined relationship, and the magnetic attraction wheel body 13 is driven to maintain the posture and the component force F2 in the tube axis direction.
As a result, an action force for pulling the driven traveling vehicle body is generated, so that the welding line can be inspected by the camera while the in-pipe traveling device 1 is integrally traveling in the pipe circumferential direction.

[Other Embodiment] In the above embodiment, the traveling vehicle bodies 10a, 10b, 20a, 20b are
In a structure in which multiple bodies are connected in series, between the front row and the rearmost traveling vehicle body, the steering angles are appropriately selected, and traveling in the pipe circumferential direction is performed while canceling the force in the pipe axial direction. Although the configuration is shown, this traveling method is such that, in the single drive traveling vehicle body 10a, 10b, the steering angle is provided between the traveling body disposed in the front portion and the traveling body disposed in the rear portion. By appropriately selecting θ (an angle within a predetermined range and further setting steering angles θ of the traveling bodies at the front portion and the rear portion in mutually opposite directions), the pipe circumferential direction is similarly set. It is possible to drive well. In the embodiment shown in FIG. 10, in the drive traveling vehicle bodies 10a and 10b provided with a single traveling vehicle body,
It shows a case where the steering angles θ of the traveling bodies at the front and rear positions are made opposite to each other and the traveling bodies rotate in the circumferential direction in the upward direction in the drawing.

The conditions for satisfying the steering angle θ of each traveling body are as follows: the weight of the driving vehicle body is W1, the distance from the inner surface of the pipe to the center of gravity is L, and the attraction force of the pair of magnetic attraction wheels is P. When the mounting width is S, the friction coefficient is μ, and the running force that can be generated by one driving means is F, the steering angle with respect to the pipe axis direction is φ when the inclination from the vertically lower side of the steering shaft is φ. The absolute value of θ is

[Equation 23] θ ≦ cos ⁻¹ (W1 × L × sin φ / (S ×
P + S × W1 × cos φ / 2)) θ ≧ sin ⁻¹ ((W1 × sin φ + (2 × P + W1 × c
osφ) × μ) / (2 × F)). Here, the above equation 21,
Comparing the correspondence with the derivation of Formula 22, since the traveling body provided in the driving vehicle body is a pair, the attraction force is
It simply becomes P. Further, the terms of the self-weight of the driven vehicle body and the attraction force are omitted. Also in this case, the in-pipe traveling device system is shown in FIG.
It will be constructed as shown in. That is, as in the previous example, the circumferential position detecting means 500 for detecting the inclination φ of the steering shaft from the vertically downward direction is provided, and the storage means 501a is provided.

Θ1 = cos ⁻¹ (W1 × L × sin φ / (S
XP + SxW1xcosφ / 2)) upper limit steering angle derivation means 502 for deriving the upper limit steering angle θ1.

Θ2 = sin ⁻¹ ((W1 × sin φ + (2 ×
P + W1 × cos φ) × μ) / (2 × F)) and a lower limit steering angle deriving means 503a for deriving a lower limit steering angle θ2, and derives an intermediate value between the upper limit steering angle θ1 and the lower limit steering angle θ2. A steering angle θ with respect to the pipe axis direction of the traveling body provided with a steering angle determination unit 504 that derives as a steering angle θ is provided in each of the front portion and the rear portion.
Can be provided with the steering angle setting means 505a for setting the absolute values of the derived steering angles in mutually opposite directions.

On the other hand, in the embodiment shown in FIG.
The in-pipe traveling device 1 is configured by connecting a plurality of traveling vehicle bodies 10a, 10b, 20a, 20b in series as in the example shown above, and each driving traveling vehicle body 10a, 10b.
In the above, the steering angles θ of the pair of traveling bodies provided in them are opposite to each other. Also in this case, traveling in the pipe circumferential direction can be favorably performed. Further, as described above, since the traveling vehicles are connected by the connecting shaft 31 via the bearing 30 which is swingable only about the axis in the width direction of the vehicle body, the linear arrangement posture of each traveling vehicle body You can run in the pipe circumferential direction while keeping the above.

[0021]

As described above, according to the present invention, there are provided: Since traveling in the pipe in the circumferential direction can be performed without complicating the structure in the limited space in the pipe, it is possible to eliminate inspection leaks of the welding line that is constructed in the pipe circumferential direction. 2. Since traveling in the pipe in the circumferential direction is possible with a minimum drive source, the volume and weight of the traveling device are not increased, and it is not necessary to increase the number of storage batteries required for driving. As a result, it is possible to travel a long distance in an arbitrary direction in a pipe inner diameter in which the pipe diameter changes in a wide range.

In the claims, reference numerals are provided for convenience of comparison with the drawings, but the present invention is not limited to the configuration shown in the attached drawings.

[Brief description of the drawings]

FIG. 1 is a diagram showing a conceptual diagram of a traveling method in the pipe circumferential direction of the present invention and a system diagram for setting a steering angle.

[Fig. 2] Relational diagram of steering angle

[Fig. 3] Relational diagram of steering angle

[Fig. 4] Relational diagram of steering angle

FIG. 5 is a side view of the in-pipe traveling device.

FIG. 6 is a sectional view of the traveling mechanism.

FIG. 7 is a sectional view of a steering mechanism.

FIG. 8 is a bottom view of a driven vehicle body.

FIG. 9 is a drawing showing the suction action of the driven vehicle body.

FIG. 10 is a diagram showing another embodiment of a circumferential traveling method in a single drive traveling vehicle body.

FIG. 11 is a diagram showing another form of the circumferential traveling method in the traveling device.

FIG. 12 is an explanatory view of a defect in the conventional pipe circumferential direction.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 In-pipe traveling device 10a Driven traveling vehicle body (front row) 10b Driven traveling vehicle body (last) 12 Axle 13 Magnetic attraction wheel body 20a Driven traveling vehicle body 20b Driven traveling vehicle body 21 Spherical wheel 22 Permanent magnet 51 Pipe inner wall surface 500 Circumferential position detecting means 502 Upper limit steering angle deriving means 503 Lower limit steering angle deriving means 503a Lower limit steering angle deriving means 504 Steering angle determining means 505 Steering angle setting means 505a Steering angle setting means 510 Traveling body steering angle control means

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Otsuo Yoshida 4-1-2, Hirano-cho, Chuo-ku, Osaka-shi, Osaka Prefecture Osaka Gas Co., Ltd. (72) Inventor Nobu Kanai Wadazaki-cho, Hyogo-ku, Kobe-shi, Hyogo 1-1-1 Mitsubishi Heavy Industries, Ltd. Kobe Shipyard (72) Inventor Yukio Fukagawa 2-1-1, Niihama, Arai-cho, Takasago-shi, Hyogo Prefecture Mitsubishi Heavy Industries Ltd. Takasago Research Laboratory (72) Inventor Reizo Miyauchi Takasago, Hyogo Prefecture 2-1-1, Niihama, Arai-machi, Yokohama-shi Takasago Laboratory, Mitsubishi Heavy Industries, Ltd.

Claims (6)

[Claims] 1. A pair of magnetic attraction wheels (13), which are configured by connecting a number of running vehicle bodies running in the pipe in series while attracting to the inner wall surface of the pipe by a magnetic attraction force and provided at both ends of an axle (12). ) Is attached to the pipe inner wall surface (51) to drive the pair of magnetic attraction wheels (13) and the magnetic attraction wheels (13) in the front-back direction of the vehicle body and the magnetic attraction wheels (13). Drive traveling vehicle body (10a) (10b) provided with a pair of traveling bodies provided with steering means for steering around a steering axis perpendicular to the axis of
And attraction means for attracting to the pipe inner wall surface (51) by a permanent magnet (22) provided in a non-contact manner with the pipe inner wall surface (51), and a spherical shape pulled by the driving traveling vehicle body (10a) (10b). A driven traveling vehicle body (20a) (20b) having traveling means for traveling on wheels (21), and the drive traveling vehicle bodies (10a) (10b) are arranged in the front row and the rearmost row, and in the middle thereof, The driven vehicle body (20a)
(20b) is arranged and each traveling vehicle body is connected in a circumferential direction about an axis in the vehicle body width direction through a rotation support mechanism having one degree of freedom by a shaft. The weight of the vehicle body (10a) (10b) is W1,
The distance from the inner wall surface of the pipe (51) to the position of the center of gravity is L, the attraction force of the pair of magnetic attraction wheels (13) is P, the mounting width is S, and the weights of all the driven vehicles (20a) (20b) are 2 × W2, W = W1 + W2, the permanent magnet (22)
K is the total attraction force per driven vehicle, the friction coefficient between the pipe inner wall surface (51) and the magnetic attraction wheel body (13) is μ, and the running force that can be generated by one drive unit in the drive unit is F, When the inclination of the steering shaft from the vertical downward direction is φ, the absolute value of the steering angle θ with respect to the pipe axis direction is as follows: θ ≦ cos ⁻¹ (W1 × L × sin φ / (S × P
+ S × W1 × cos φ / 2)) θ ≧ sin ⁻¹ ((W × sin φ + (2 × P + K + W × c
osφ) × μ) / (2 × F)), and the front row and the rearmost driving vehicle body (10a) (10)
The steering angle θ of b) is set in mutually opposite directions,
A circumferential traveling method of a traveling device in a pipe that travels in the pipe in the circumferential direction. 2. A pair of magnetic attraction wheels (13) provided on both ends of an axle (12), which are constructed by connecting a number of running vehicle bodies running in the tube in series while attracting to the inner wall surface of the tube by a magnetic attraction force. ) By a suction means to the inner wall surface (51) of the pipe to drive the pair of magnetic attraction wheels (13), and the magnetic attraction wheels (13) in the longitudinal direction of the vehicle body and the magnetic attraction wheels (13). Drive traveling vehicle body (10a) provided with a pair of traveling bodies provided with steering means for steering around a steering axis that is perpendicular to the axis of the vehicle and divided into a front portion and a rear portion of the vehicle body.
(10b), attraction means for attracting to the pipe inner wall surface (51) by a permanent magnet (22) provided in non-contact with the pipe inner wall surface (51), and towing to the drive traveling vehicle body (10a) (10b). Driven vehicle bodies (20a), (20b) provided with traveling means that are driven by spherical wheels (21), the drive traveling vehicle bodies (10a), (10b) being arranged in the front row and the rearmost, In the middle, the driven vehicle body (20a)
(20b) is arranged and each traveling vehicle body is connected by a shaft around a shaft in the width direction of the vehicle through a rotation support mechanism having one degree of freedom. A circumferential position detecting means (500) for detecting the inclination φ is provided, and the own weight of the driving traveling vehicle body (10a) (10b) is W1,
The distance from the inner wall surface of the pipe (51) to the position of the center of gravity is L, the attraction force of the pair of magnetic attraction wheels (13) is P, the mounting width is S, and the weights of all the driven vehicles (20a) (20b) are 2 × W2, W = W1 + W2, the total attraction force of the permanent magnet (22) per driven vehicle body is K, the friction coefficient between the pipe inner wall surface (51) and the magnetic attraction wheel body (13) is μ, and the drive is performed. When the driving force that can be generated by one driving means is F, the following equation is obtained: θ1 = cos ⁻¹ (W1 × L × sin φ / (S ×
P + S × W1 × cos φ / 2)) and an upper limit steering angle derivation means (502) for deriving an upper limit steering angle θ1, and θ2 = sin ⁻¹ ((W × sin φ + (2 × P +
K + W × cos φ) × μ) / (2 × F)) The lower limit steering angle deriving means (503) for deriving the lower limit steering angle θ2 represented by A steering angle determining means (504) for deriving a value as a derived steering angle is provided, and the frontmost row and the rearmost drive traveling vehicle body (10a) (10).
An in-pipe traveling device comprising steering angle setting means (505) for setting steering angles θ with respect to the pipe axis direction of b) in directions opposite to each other with the derived steering angles being absolute values. 3. A traveling vehicle body that travels in the pipe while being attracted to the inner wall surface of the pipe by a magnetic attraction force, and is attached to the inner wall surface (51) of the pipe by a pair of magnetic attraction wheels (13) provided at both ends of the axle (12). A drive means for adsorbing and driving the pair of magnetic attraction wheels (13), and the magnetic attraction wheel body (13) in the front-back direction of the vehicle body and around the steering axis perpendicular to the axis of the magnetic attraction wheel body (13). Traveling bodies equipped with steering means for steering are arranged at front and rear portions of the drive traveling vehicle bodies (10a), (10b), and the steering axes of the respective traveling bodies are set at the drive traveling vehicle bodies (10a), (10b). A method for traveling in a circumferential direction of a traveling device in a pipe arranged in the front-rear direction of the vehicle, wherein the self-weight of the drive traveling vehicle body (10a) (10b) is W1,
Between the inner wall surface of the pipe (51) and the magnetic attraction ring (13), the distance from the inner wall surface of the tube to the position of the center of gravity is L, the attraction force of the pair of magnetic attraction ring bodies (13) is P, the mounting width is S. Where μ is the friction coefficient, F is the traveling force that can be generated by the drive means by one drive means, and φ is the inclination of the steering shaft from below vertically, the steering angle θ with respect to the pipe axis direction has an absolute value of Equation 4 θ ≦ cos ⁻¹ (W1 × L × sin φ / (S × P
+ S × W1 × cos φ / 2) θ ≧ sin ⁻¹ ((W1 × sin φ + (2 × P + W1 × c
osφ) × μ) / (2 × F)), and the steering angles θ of the traveling bodies arranged in the front portion and the rear portion are set in mutually opposite directions. Then, a method of traveling in the pipe in the circumferential direction of the traveling device in the pipe in the circumferential direction. 4. A traveling vehicle body that travels inside the pipe while being attracted to the inner wall surface of the pipe by a magnetic attraction force. The pair of magnetic attraction wheels (13) provided at both ends of the axle (12) is attached to the inner wall surface (51) of the pipe. A drive means for adsorbing and driving the pair of magnetic attraction wheels (13), and the magnetic attraction wheel body (13) around the steering shaft perpendicular to the longitudinal direction of the vehicle body and the axis of the magnetic attraction wheel body (13). A traveling body having steering means for steering the vehicle is arranged at a front portion and a rear portion of the driving traveling vehicle body (10a) (10b), and the steering shaft of each traveling body is set to the driving traveling vehicle body (10a) (10b). ) Is arranged in the front-rear direction and is provided in the pipe traveling device, which is provided with a circumferential position detecting means (500) for detecting an inclination φ of the steering shaft from a vertically downward direction, and the driving traveling vehicle body (10a) (10b). Weight of W1,
Between the inner wall surface of the pipe (51) and the magnetic attraction ring (13), the distance from the inner wall surface of the tube to the position of the center of gravity is L, the attraction force of the pair of magnetic attraction ring bodies (13) is P, the mounting width is S. Where μ is the friction coefficient and F is the running force that can be generated by one driving means, θ1 = cos ⁻¹ (W1 × L × sin φ / (S ×
P + S × W1 × cos φ / 2)) upper limit steering angle derivation means (502) for deriving an upper limit steering angle θ1, and θ2 = sin ⁻¹ ((W1 × sin φ + (2 × P
+ W1 × cos φ) × μ) / (2 × F)) and a lower limit steering angle derivation means (503a) for deriving a lower limit steering angle θ2, and an intermediate value between the upper limit steering angle θ1 and the lower limit steering angle θ2. Is provided as a derived steering angle θ, and the absolute value of the steering angle θ with respect to the pipe axis direction of the traveling body disposed in each of the front part and the rear part is derived. An in-pipe traveling device comprising steering angle setting means (505a) for setting steering angles in mutually opposite directions. 5. A traveling vehicle body that travels in the pipe while being attracted to the inner wall surface of the pipe by a magnetic attraction force, and is formed on the inner wall surface (51) of the pipe by a pair of magnetic attraction wheels (13) provided at both ends of the axle (12). A drive means for adsorbing and driving the pair of magnetic attraction wheels (13), and the magnetic attraction wheel body (13) in the front-back direction of the vehicle body and around the steering axis perpendicular to the axis of the magnetic attraction wheel body (13). A drive traveling vehicle body (10a) (10) provided with a pair of traveling bodies provided with a steering means for steering, which are divided into a vehicle body front portion and a vehicle body rear portion.
b) A traveling device (1) including a circumferential position detecting means (501) for detecting an inclination φ of the steering shaft from a vertically downward direction, which is detected by the circumferential position detecting means (501). An in-pipe traveling apparatus comprising traveling body steering angle control means (510) for setting and controlling a steering angle θ of the traveling body with respect to a pipe axis direction based on the inclination φ. 6. The vehicle steering angle control means (510)
Which is based on the inclination φ detected by the circumferential position detecting means (501) with respect to the own weight of the driving traveling vehicle body (10a) (10b) and the attraction force of the magnetic attraction wheel body (13). Upper limit steering angle derivation means (502) for deriving the upper limit steering angle θ1 determined from the moment balance around the magnetic attraction wheel body (13), and the weight load and the magnetism applied to the drive traveling vehicle bodies (10a) (10b). Regarding the suction load, the circumferential position detecting means (5
01), the lower limit steering angle deriving means (503) (503a) for deriving the lower limit steering angle θ2 determined from the traveling resistance force, based on the inclination φ detected by the traveling resistance force. The control for setting the steering angle θ of the traveling body to a value between the steering angle θ2 and the steering angle θ2.
The in-pipe traveling device according to any one of the preceding claims.